/*
 * Copyright (C) 2012 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package android.hardware.camera2;

import android.annotation.NonNull;
import android.annotation.Nullable;
import android.hardware.camera2.impl.CameraMetadataNative;
import android.hardware.camera2.impl.CaptureResultExtras;
import android.hardware.camera2.impl.PublicKey;
import android.hardware.camera2.impl.SyntheticKey;
import android.hardware.camera2.utils.TypeReference;
import android.util.Log;
import android.util.Rational;

import java.util.List;

/**
 * <p>The subset of the results of a single image capture from the image sensor.</p>
 *
 * <p>Contains a subset of the final configuration for the capture hardware (sensor, lens,
 * flash), the processing pipeline, the control algorithms, and the output
 * buffers.</p>
 *
 * <p>CaptureResults are produced by a {@link CameraDevice} after processing a
 * {@link CaptureRequest}. All properties listed for capture requests can also
 * be queried on the capture result, to determine the final values used for
 * capture. The result also includes additional metadata about the state of the
 * camera device during the capture.</p>
 *
 * <p>Not all properties returned by {@link CameraCharacteristics#getAvailableCaptureResultKeys()}
 * are necessarily available. Some results are {@link CaptureResult partial} and will
 * not have every key set. Only {@link TotalCaptureResult total} results are guaranteed to have
 * every key available that was enabled by the request.</p>
 *
 * <p>{@link CaptureResult} objects are immutable.</p>
 *
 */
public class CaptureResult extends CameraMetadata<CaptureResult.Key<?>> {

    private static final String TAG = "CaptureResult";
    private static final boolean VERBOSE = false;

    /**
     * A {@code Key} is used to do capture result field lookups with
     * {@link CaptureResult#get}.
     *
     * <p>For example, to get the timestamp corresponding to the exposure of the first row:
     * <code><pre>
     * long timestamp = captureResult.get(CaptureResult.SENSOR_TIMESTAMP);
     * </pre></code>
     * </p>
     *
     * <p>To enumerate over all possible keys for {@link CaptureResult}, see
     * {@link CameraCharacteristics#getAvailableCaptureResultKeys}.</p>
     *
     * @see CaptureResult#get
     * @see CameraCharacteristics#getAvailableCaptureResultKeys
     */
    public final static class Key<T> {
        private final CameraMetadataNative.Key<T> mKey;

        /**
         * Visible for testing and vendor extensions only.
         *
         * @hide
         */
        public Key(String name, Class<T> type) {
            mKey = new CameraMetadataNative.Key<T>(name, type);
        }

        /**
         * Visible for testing and vendor extensions only.
         *
         * @hide
         */
        public Key(String name, TypeReference<T> typeReference) {
            mKey = new CameraMetadataNative.Key<T>(name, typeReference);
        }

        /**
         * Return a camelCase, period separated name formatted like:
         * {@code "root.section[.subsections].name"}.
         *
         * <p>Built-in keys exposed by the Android SDK are always prefixed with {@code "android."};
         * keys that are device/platform-specific are prefixed with {@code "com."}.</p>
         *
         * <p>For example, {@code CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP} would
         * have a name of {@code "android.scaler.streamConfigurationMap"}; whereas a device
         * specific key might look like {@code "com.google.nexus.data.private"}.</p>
         *
         * @return String representation of the key name
         */
        @NonNull
        public String getName() {
            return mKey.getName();
        }

        /**
         * {@inheritDoc}
         */
        @Override
        public final int hashCode() {
            return mKey.hashCode();
        }

        /**
         * {@inheritDoc}
         */
        @SuppressWarnings("unchecked")
        @Override
        public final boolean equals(Object o) {
            return o instanceof Key && ((Key<T>)o).mKey.equals(mKey);
        }

        /**
         * Return this {@link Key} as a string representation.
         *
         * <p>{@code "CaptureResult.Key(%s)"}, where {@code %s} represents
         * the name of this key as returned by {@link #getName}.</p>
         *
         * @return string representation of {@link Key}
         */
        @NonNull
        @Override
        public String toString() {
            return String.format("CaptureResult.Key(%s)", mKey.getName());
        }

        /**
         * Visible for CameraMetadataNative implementation only; do not use.
         *
         * TODO: Make this private or remove it altogether.
         *
         * @hide
         */
        public CameraMetadataNative.Key<T> getNativeKey() {
            return mKey;
        }

        @SuppressWarnings({ "unchecked" })
        /*package*/ Key(CameraMetadataNative.Key<?> nativeKey) {
            mKey = (CameraMetadataNative.Key<T>) nativeKey;
        }
    }

    private final CameraMetadataNative mResults;
    private final CaptureRequest mRequest;
    private final int mSequenceId;
    private final long mFrameNumber;

    /**
     * Takes ownership of the passed-in properties object
     *
     * <p>For internal use only</p>
     * @hide
     */
    public CaptureResult(CameraMetadataNative results, CaptureRequest parent,
            CaptureResultExtras extras) {
        if (results == null) {
            throw new IllegalArgumentException("results was null");
        }

        if (parent == null) {
            throw new IllegalArgumentException("parent was null");
        }

        if (extras == null) {
            throw new IllegalArgumentException("extras was null");
        }

        mResults = CameraMetadataNative.move(results);
        if (mResults.isEmpty()) {
            throw new AssertionError("Results must not be empty");
        }
        mRequest = parent;
        mSequenceId = extras.getRequestId();
        mFrameNumber = extras.getFrameNumber();
    }

    /**
     * Returns a copy of the underlying {@link CameraMetadataNative}.
     * @hide
     */
    public CameraMetadataNative getNativeCopy() {
        return new CameraMetadataNative(mResults);
    }

    /**
     * Creates a request-less result.
     *
     * <p><strong>For testing only.</strong></p>
     * @hide
     */
    public CaptureResult(CameraMetadataNative results, int sequenceId) {
        if (results == null) {
            throw new IllegalArgumentException("results was null");
        }

        mResults = CameraMetadataNative.move(results);
        if (mResults.isEmpty()) {
            throw new AssertionError("Results must not be empty");
        }

        mRequest = null;
        mSequenceId = sequenceId;
        mFrameNumber = -1;
    }

    /**
     * Get a capture result field value.
     *
     * <p>The field definitions can be found in {@link CaptureResult}.</p>
     *
     * <p>Querying the value for the same key more than once will return a value
     * which is equal to the previous queried value.</p>
     *
     * @throws IllegalArgumentException if the key was not valid
     *
     * @param key The result field to read.
     * @return The value of that key, or {@code null} if the field is not set.
     */
    @Nullable
    public <T> T get(Key<T> key) {
        T value = mResults.get(key);
        if (VERBOSE) Log.v(TAG, "#get for Key = " + key.getName() + ", returned value = " + value);
        return value;
    }

    /**
     * {@inheritDoc}
     * @hide
     */
    @SuppressWarnings("unchecked")
    @Override
    protected <T> T getProtected(Key<?> key) {
        return (T) mResults.get(key);
    }

    /**
     * {@inheritDoc}
     * @hide
     */
    @SuppressWarnings("unchecked")
    @Override
    protected Class<Key<?>> getKeyClass() {
        Object thisClass = Key.class;
        return (Class<Key<?>>)thisClass;
    }

    /**
     * Dumps the native metadata contents to logcat.
     *
     * <p>Visibility for testing/debugging only. The results will not
     * include any synthesized keys, as they are invisible to the native layer.</p>
     *
     * @hide
     */
    public void dumpToLog() {
        mResults.dumpToLog();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    @NonNull
    public List<Key<?>> getKeys() {
        // Force the javadoc for this function to show up on the CaptureResult page
        return super.getKeys();
    }

    /**
     * Get the request associated with this result.
     *
     * <p>Whenever a request has been fully or partially captured, with
     * {@link CameraCaptureSession.CaptureCallback#onCaptureCompleted} or
     * {@link CameraCaptureSession.CaptureCallback#onCaptureProgressed}, the {@code result}'s
     * {@code getRequest()} will return that {@code request}.
     * </p>
     *
     * <p>For example,
     * <code><pre>cameraDevice.capture(someRequest, new CaptureCallback() {
     *     {@literal @}Override
     *     void onCaptureCompleted(CaptureRequest myRequest, CaptureResult myResult) {
     *         assert(myResult.getRequest.equals(myRequest) == true);
     *     }
     * }, null);
     * </code></pre>
     * </p>
     *
     * @return The request associated with this result. Never {@code null}.
     */
    @NonNull
    public CaptureRequest getRequest() {
        return mRequest;
    }

    /**
     * Get the frame number associated with this result.
     *
     * <p>Whenever a request has been processed, regardless of failure or success,
     * it gets a unique frame number assigned to its future result/failure.</p>
     *
     * <p>For the same type of request (capturing from the camera device or reprocessing), this
     * value monotonically increments, starting with 0, for every new result or failure and the
     * scope is the lifetime of the {@link CameraDevice}. Between different types of requests,
     * the frame number may not monotonically increment. For example, the frame number of a newer
     * reprocess result may be smaller than the frame number of an older result of capturing new
     * images from the camera device, but the frame number of a newer reprocess result will never be
     * smaller than the frame number of an older reprocess result.</p>
     *
     * @return The frame number
     *
     * @see CameraDevice#createCaptureRequest
     * @see CameraDevice#createReprocessCaptureRequest
     */
    public long getFrameNumber() {
        return mFrameNumber;
    }

    /**
     * The sequence ID for this failure that was returned by the
     * {@link CameraCaptureSession#capture} family of functions.
     *
     * <p>The sequence ID is a unique monotonically increasing value starting from 0,
     * incremented every time a new group of requests is submitted to the CameraDevice.</p>
     *
     * @return int The ID for the sequence of requests that this capture result is a part of
     *
     * @see CameraDevice.CaptureCallback#onCaptureSequenceCompleted
     * @see CameraDevice.CaptureCallback#onCaptureSequenceAborted
     */
    public int getSequenceId() {
        return mSequenceId;
    }

    /*@O~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~
     * The key entries below this point are generated from metadata
     * definitions in /system/media/camera/docs. Do not modify by hand or
     * modify the comment blocks at the start or end.
     *~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~*/

    /**
     * <p>The mode control selects how the image data is converted from the
     * sensor's native color into linear sRGB color.</p>
     * <p>When auto-white balance (AWB) is enabled with {@link CaptureRequest#CONTROL_AWB_MODE android.control.awbMode}, this
     * control is overridden by the AWB routine. When AWB is disabled, the
     * application controls how the color mapping is performed.</p>
     * <p>We define the expected processing pipeline below. For consistency
     * across devices, this is always the case with TRANSFORM_MATRIX.</p>
     * <p>When either FULL or HIGH_QUALITY is used, the camera device may
     * do additional processing but {@link CaptureRequest#COLOR_CORRECTION_GAINS android.colorCorrection.gains} and
     * {@link CaptureRequest#COLOR_CORRECTION_TRANSFORM android.colorCorrection.transform} will still be provided by the
     * camera device (in the results) and be roughly correct.</p>
     * <p>Switching to TRANSFORM_MATRIX and using the data provided from
     * FAST or HIGH_QUALITY will yield a picture with the same white point
     * as what was produced by the camera device in the earlier frame.</p>
     * <p>The expected processing pipeline is as follows:</p>
     * <p><img alt="White balance processing pipeline" src="../../../../images/camera2/metadata/android.colorCorrection.mode/processing_pipeline.png" /></p>
     * <p>The white balance is encoded by two values, a 4-channel white-balance
     * gain vector (applied in the Bayer domain), and a 3x3 color transform
     * matrix (applied after demosaic).</p>
     * <p>The 4-channel white-balance gains are defined as:</p>
     * <pre><code>{@link CaptureRequest#COLOR_CORRECTION_GAINS android.colorCorrection.gains} = [ R G_even G_odd B ]
     * </code></pre>
     * <p>where <code>G_even</code> is the gain for green pixels on even rows of the
     * output, and <code>G_odd</code> is the gain for green pixels on the odd rows.
     * These may be identical for a given camera device implementation; if
     * the camera device does not support a separate gain for even/odd green
     * channels, it will use the <code>G_even</code> value, and write <code>G_odd</code> equal to
     * <code>G_even</code> in the output result metadata.</p>
     * <p>The matrices for color transforms are defined as a 9-entry vector:</p>
     * <pre><code>{@link CaptureRequest#COLOR_CORRECTION_TRANSFORM android.colorCorrection.transform} = [ I0 I1 I2 I3 I4 I5 I6 I7 I8 ]
     * </code></pre>
     * <p>which define a transform from input sensor colors, <code>P_in = [ r g b ]</code>,
     * to output linear sRGB, <code>P_out = [ r' g' b' ]</code>,</p>
     * <p>with colors as follows:</p>
     * <pre><code>r' = I0r + I1g + I2b
     * g' = I3r + I4g + I5b
     * b' = I6r + I7g + I8b
     * </code></pre>
     * <p>Both the input and output value ranges must match. Overflow/underflow
     * values are clipped to fit within the range.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #COLOR_CORRECTION_MODE_TRANSFORM_MATRIX TRANSFORM_MATRIX}</li>
     *   <li>{@link #COLOR_CORRECTION_MODE_FAST FAST}</li>
     *   <li>{@link #COLOR_CORRECTION_MODE_HIGH_QUALITY HIGH_QUALITY}</li>
     * </ul></p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#COLOR_CORRECTION_GAINS
     * @see CaptureRequest#COLOR_CORRECTION_TRANSFORM
     * @see CaptureRequest#CONTROL_AWB_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see #COLOR_CORRECTION_MODE_TRANSFORM_MATRIX
     * @see #COLOR_CORRECTION_MODE_FAST
     * @see #COLOR_CORRECTION_MODE_HIGH_QUALITY
     */
    @PublicKey
    public static final Key<Integer> COLOR_CORRECTION_MODE =
            new Key<Integer>("android.colorCorrection.mode", int.class);

    /**
     * <p>A color transform matrix to use to transform
     * from sensor RGB color space to output linear sRGB color space.</p>
     * <p>This matrix is either set by the camera device when the request
     * {@link CaptureRequest#COLOR_CORRECTION_MODE android.colorCorrection.mode} is not TRANSFORM_MATRIX, or
     * directly by the application in the request when the
     * {@link CaptureRequest#COLOR_CORRECTION_MODE android.colorCorrection.mode} is TRANSFORM_MATRIX.</p>
     * <p>In the latter case, the camera device may round the matrix to account
     * for precision issues; the final rounded matrix should be reported back
     * in this matrix result metadata. The transform should keep the magnitude
     * of the output color values within <code>[0, 1.0]</code> (assuming input color
     * values is within the normalized range <code>[0, 1.0]</code>), or clipping may occur.</p>
     * <p>The valid range of each matrix element varies on different devices, but
     * values within [-1.5, 3.0] are guaranteed not to be clipped.</p>
     * <p><b>Units</b>: Unitless scale factors</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#COLOR_CORRECTION_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     */
    @PublicKey
    public static final Key<android.hardware.camera2.params.ColorSpaceTransform> COLOR_CORRECTION_TRANSFORM =
            new Key<android.hardware.camera2.params.ColorSpaceTransform>("android.colorCorrection.transform", android.hardware.camera2.params.ColorSpaceTransform.class);

    /**
     * <p>Gains applying to Bayer raw color channels for
     * white-balance.</p>
     * <p>These per-channel gains are either set by the camera device
     * when the request {@link CaptureRequest#COLOR_CORRECTION_MODE android.colorCorrection.mode} is not
     * TRANSFORM_MATRIX, or directly by the application in the
     * request when the {@link CaptureRequest#COLOR_CORRECTION_MODE android.colorCorrection.mode} is
     * TRANSFORM_MATRIX.</p>
     * <p>The gains in the result metadata are the gains actually
     * applied by the camera device to the current frame.</p>
     * <p>The valid range of gains varies on different devices, but gains
     * between [1.0, 3.0] are guaranteed not to be clipped. Even if a given
     * device allows gains below 1.0, this is usually not recommended because
     * this can create color artifacts.</p>
     * <p><b>Units</b>: Unitless gain factors</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#COLOR_CORRECTION_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     */
    @PublicKey
    public static final Key<android.hardware.camera2.params.RggbChannelVector> COLOR_CORRECTION_GAINS =
            new Key<android.hardware.camera2.params.RggbChannelVector>("android.colorCorrection.gains", android.hardware.camera2.params.RggbChannelVector.class);

    /**
     * <p>Mode of operation for the chromatic aberration correction algorithm.</p>
     * <p>Chromatic (color) aberration is caused by the fact that different wavelengths of light
     * can not focus on the same point after exiting from the lens. This metadata defines
     * the high level control of chromatic aberration correction algorithm, which aims to
     * minimize the chromatic artifacts that may occur along the object boundaries in an
     * image.</p>
     * <p>FAST/HIGH_QUALITY both mean that camera device determined aberration
     * correction will be applied. HIGH_QUALITY mode indicates that the camera device will
     * use the highest-quality aberration correction algorithms, even if it slows down
     * capture rate. FAST means the camera device will not slow down capture rate when
     * applying aberration correction.</p>
     * <p>LEGACY devices will always be in FAST mode.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #COLOR_CORRECTION_ABERRATION_MODE_OFF OFF}</li>
     *   <li>{@link #COLOR_CORRECTION_ABERRATION_MODE_FAST FAST}</li>
     *   <li>{@link #COLOR_CORRECTION_ABERRATION_MODE_HIGH_QUALITY HIGH_QUALITY}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#COLOR_CORRECTION_AVAILABLE_ABERRATION_MODES android.colorCorrection.availableAberrationModes}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#COLOR_CORRECTION_AVAILABLE_ABERRATION_MODES
     * @see #COLOR_CORRECTION_ABERRATION_MODE_OFF
     * @see #COLOR_CORRECTION_ABERRATION_MODE_FAST
     * @see #COLOR_CORRECTION_ABERRATION_MODE_HIGH_QUALITY
     */
    @PublicKey
    public static final Key<Integer> COLOR_CORRECTION_ABERRATION_MODE =
            new Key<Integer>("android.colorCorrection.aberrationMode", int.class);

    /**
     * <p>The desired setting for the camera device's auto-exposure
     * algorithm's antibanding compensation.</p>
     * <p>Some kinds of lighting fixtures, such as some fluorescent
     * lights, flicker at the rate of the power supply frequency
     * (60Hz or 50Hz, depending on country). While this is
     * typically not noticeable to a person, it can be visible to
     * a camera device. If a camera sets its exposure time to the
     * wrong value, the flicker may become visible in the
     * viewfinder as flicker or in a final captured image, as a
     * set of variable-brightness bands across the image.</p>
     * <p>Therefore, the auto-exposure routines of camera devices
     * include antibanding routines that ensure that the chosen
     * exposure value will not cause such banding. The choice of
     * exposure time depends on the rate of flicker, which the
     * camera device can detect automatically, or the expected
     * rate can be selected by the application using this
     * control.</p>
     * <p>A given camera device may not support all of the possible
     * options for the antibanding mode. The
     * {@link CameraCharacteristics#CONTROL_AE_AVAILABLE_ANTIBANDING_MODES android.control.aeAvailableAntibandingModes} key contains
     * the available modes for a given camera device.</p>
     * <p>AUTO mode is the default if it is available on given
     * camera device. When AUTO mode is not available, the
     * default will be either 50HZ or 60HZ, and both 50HZ
     * and 60HZ will be available.</p>
     * <p>If manual exposure control is enabled (by setting
     * {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} or {@link CaptureRequest#CONTROL_MODE android.control.mode} to OFF),
     * then this setting has no effect, and the application must
     * ensure it selects exposure times that do not cause banding
     * issues. The {@link CaptureResult#STATISTICS_SCENE_FLICKER android.statistics.sceneFlicker} key can assist
     * the application in this.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_AE_ANTIBANDING_MODE_OFF OFF}</li>
     *   <li>{@link #CONTROL_AE_ANTIBANDING_MODE_50HZ 50HZ}</li>
     *   <li>{@link #CONTROL_AE_ANTIBANDING_MODE_60HZ 60HZ}</li>
     *   <li>{@link #CONTROL_AE_ANTIBANDING_MODE_AUTO AUTO}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br></p>
     * <p>{@link CameraCharacteristics#CONTROL_AE_AVAILABLE_ANTIBANDING_MODES android.control.aeAvailableAntibandingModes}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#CONTROL_AE_AVAILABLE_ANTIBANDING_MODES
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CaptureRequest#CONTROL_MODE
     * @see CaptureResult#STATISTICS_SCENE_FLICKER
     * @see #CONTROL_AE_ANTIBANDING_MODE_OFF
     * @see #CONTROL_AE_ANTIBANDING_MODE_50HZ
     * @see #CONTROL_AE_ANTIBANDING_MODE_60HZ
     * @see #CONTROL_AE_ANTIBANDING_MODE_AUTO
     */
    @PublicKey
    public static final Key<Integer> CONTROL_AE_ANTIBANDING_MODE =
            new Key<Integer>("android.control.aeAntibandingMode", int.class);

    /**
     * <p>Adjustment to auto-exposure (AE) target image
     * brightness.</p>
     * <p>The adjustment is measured as a count of steps, with the
     * step size defined by {@link CameraCharacteristics#CONTROL_AE_COMPENSATION_STEP android.control.aeCompensationStep} and the
     * allowed range by {@link CameraCharacteristics#CONTROL_AE_COMPENSATION_RANGE android.control.aeCompensationRange}.</p>
     * <p>For example, if the exposure value (EV) step is 0.333, '6'
     * will mean an exposure compensation of +2 EV; -3 will mean an
     * exposure compensation of -1 EV. One EV represents a doubling
     * of image brightness. Note that this control will only be
     * effective if {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} <code>!=</code> OFF. This control
     * will take effect even when {@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} <code>== true</code>.</p>
     * <p>In the event of exposure compensation value being changed, camera device
     * may take several frames to reach the newly requested exposure target.
     * During that time, {@link CaptureResult#CONTROL_AE_STATE android.control.aeState} field will be in the SEARCHING
     * state. Once the new exposure target is reached, {@link CaptureResult#CONTROL_AE_STATE android.control.aeState} will
     * change from SEARCHING to either CONVERGED, LOCKED (if AE lock is enabled), or
     * FLASH_REQUIRED (if the scene is too dark for still capture).</p>
     * <p><b>Units</b>: Compensation steps</p>
     * <p><b>Range of valid values:</b><br>
     * {@link CameraCharacteristics#CONTROL_AE_COMPENSATION_RANGE android.control.aeCompensationRange}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#CONTROL_AE_COMPENSATION_RANGE
     * @see CameraCharacteristics#CONTROL_AE_COMPENSATION_STEP
     * @see CaptureRequest#CONTROL_AE_LOCK
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CaptureResult#CONTROL_AE_STATE
     */
    @PublicKey
    public static final Key<Integer> CONTROL_AE_EXPOSURE_COMPENSATION =
            new Key<Integer>("android.control.aeExposureCompensation", int.class);

    /**
     * <p>Whether auto-exposure (AE) is currently locked to its latest
     * calculated values.</p>
     * <p>When set to <code>true</code> (ON), the AE algorithm is locked to its latest parameters,
     * and will not change exposure settings until the lock is set to <code>false</code> (OFF).</p>
     * <p>Note that even when AE is locked, the flash may be fired if
     * the {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} is ON_AUTO_FLASH /
     * ON_ALWAYS_FLASH / ON_AUTO_FLASH_REDEYE.</p>
     * <p>When {@link CaptureRequest#CONTROL_AE_EXPOSURE_COMPENSATION android.control.aeExposureCompensation} is changed, even if the AE lock
     * is ON, the camera device will still adjust its exposure value.</p>
     * <p>If AE precapture is triggered (see {@link CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER android.control.aePrecaptureTrigger})
     * when AE is already locked, the camera device will not change the exposure time
     * ({@link CaptureRequest#SENSOR_EXPOSURE_TIME android.sensor.exposureTime}) and sensitivity ({@link CaptureRequest#SENSOR_SENSITIVITY android.sensor.sensitivity})
     * parameters. The flash may be fired if the {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode}
     * is ON_AUTO_FLASH/ON_AUTO_FLASH_REDEYE and the scene is too dark. If the
     * {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} is ON_ALWAYS_FLASH, the scene may become overexposed.
     * Similarly, AE precapture trigger CANCEL has no effect when AE is already locked.</p>
     * <p>When an AE precapture sequence is triggered, AE unlock will not be able to unlock
     * the AE if AE is locked by the camera device internally during precapture metering
     * sequence In other words, submitting requests with AE unlock has no effect for an
     * ongoing precapture metering sequence. Otherwise, the precapture metering sequence
     * will never succeed in a sequence of preview requests where AE lock is always set
     * to <code>false</code>.</p>
     * <p>Since the camera device has a pipeline of in-flight requests, the settings that
     * get locked do not necessarily correspond to the settings that were present in the
     * latest capture result received from the camera device, since additional captures
     * and AE updates may have occurred even before the result was sent out. If an
     * application is switching between automatic and manual control and wishes to eliminate
     * any flicker during the switch, the following procedure is recommended:</p>
     * <ol>
     * <li>Starting in auto-AE mode:</li>
     * <li>Lock AE</li>
     * <li>Wait for the first result to be output that has the AE locked</li>
     * <li>Copy exposure settings from that result into a request, set the request to manual AE</li>
     * <li>Submit the capture request, proceed to run manual AE as desired.</li>
     * </ol>
     * <p>See {@link CaptureResult#CONTROL_AE_STATE android.control.aeState} for AE lock related state transition details.</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#CONTROL_AE_EXPOSURE_COMPENSATION
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER
     * @see CaptureResult#CONTROL_AE_STATE
     * @see CaptureRequest#SENSOR_EXPOSURE_TIME
     * @see CaptureRequest#SENSOR_SENSITIVITY
     */
    @PublicKey
    public static final Key<Boolean> CONTROL_AE_LOCK =
            new Key<Boolean>("android.control.aeLock", boolean.class);

    /**
     * <p>The desired mode for the camera device's
     * auto-exposure routine.</p>
     * <p>This control is only effective if {@link CaptureRequest#CONTROL_MODE android.control.mode} is
     * AUTO.</p>
     * <p>When set to any of the ON modes, the camera device's
     * auto-exposure routine is enabled, overriding the
     * application's selected exposure time, sensor sensitivity,
     * and frame duration ({@link CaptureRequest#SENSOR_EXPOSURE_TIME android.sensor.exposureTime},
     * {@link CaptureRequest#SENSOR_SENSITIVITY android.sensor.sensitivity}, and
     * {@link CaptureRequest#SENSOR_FRAME_DURATION android.sensor.frameDuration}). If one of the FLASH modes
     * is selected, the camera device's flash unit controls are
     * also overridden.</p>
     * <p>The FLASH modes are only available if the camera device
     * has a flash unit ({@link CameraCharacteristics#FLASH_INFO_AVAILABLE android.flash.info.available} is <code>true</code>).</p>
     * <p>If flash TORCH mode is desired, this field must be set to
     * ON or OFF, and {@link CaptureRequest#FLASH_MODE android.flash.mode} set to TORCH.</p>
     * <p>When set to any of the ON modes, the values chosen by the
     * camera device auto-exposure routine for the overridden
     * fields for a given capture will be available in its
     * CaptureResult.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_AE_MODE_OFF OFF}</li>
     *   <li>{@link #CONTROL_AE_MODE_ON ON}</li>
     *   <li>{@link #CONTROL_AE_MODE_ON_AUTO_FLASH ON_AUTO_FLASH}</li>
     *   <li>{@link #CONTROL_AE_MODE_ON_ALWAYS_FLASH ON_ALWAYS_FLASH}</li>
     *   <li>{@link #CONTROL_AE_MODE_ON_AUTO_FLASH_REDEYE ON_AUTO_FLASH_REDEYE}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#CONTROL_AE_AVAILABLE_MODES android.control.aeAvailableModes}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#CONTROL_AE_AVAILABLE_MODES
     * @see CaptureRequest#CONTROL_MODE
     * @see CameraCharacteristics#FLASH_INFO_AVAILABLE
     * @see CaptureRequest#FLASH_MODE
     * @see CaptureRequest#SENSOR_EXPOSURE_TIME
     * @see CaptureRequest#SENSOR_FRAME_DURATION
     * @see CaptureRequest#SENSOR_SENSITIVITY
     * @see #CONTROL_AE_MODE_OFF
     * @see #CONTROL_AE_MODE_ON
     * @see #CONTROL_AE_MODE_ON_AUTO_FLASH
     * @see #CONTROL_AE_MODE_ON_ALWAYS_FLASH
     * @see #CONTROL_AE_MODE_ON_AUTO_FLASH_REDEYE
     */
    @PublicKey
    public static final Key<Integer> CONTROL_AE_MODE =
            new Key<Integer>("android.control.aeMode", int.class);

    /**
     * <p>List of metering areas to use for auto-exposure adjustment.</p>
     * <p>Not available if {@link CameraCharacteristics#CONTROL_MAX_REGIONS_AE android.control.maxRegionsAe} is 0.
     * Otherwise will always be present.</p>
     * <p>The maximum number of regions supported by the device is determined by the value
     * of {@link CameraCharacteristics#CONTROL_MAX_REGIONS_AE android.control.maxRegionsAe}.</p>
     * <p>The coordinate system is based on the active pixel array,
     * with (0,0) being the top-left pixel in the active pixel array, and
     * ({@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}.width - 1,
     * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}.height - 1) being the
     * bottom-right pixel in the active pixel array.</p>
     * <p>The weight must be within <code>[0, 1000]</code>, and represents a weight
     * for every pixel in the area. This means that a large metering area
     * with the same weight as a smaller area will have more effect in
     * the metering result. Metering areas can partially overlap and the
     * camera device will add the weights in the overlap region.</p>
     * <p>The weights are relative to weights of other exposure metering regions, so if only one
     * region is used, all non-zero weights will have the same effect. A region with 0
     * weight is ignored.</p>
     * <p>If all regions have 0 weight, then no specific metering area needs to be used by the
     * camera device.</p>
     * <p>If the metering region is outside the used {@link CaptureRequest#SCALER_CROP_REGION android.scaler.cropRegion} returned in
     * capture result metadata, the camera device will ignore the sections outside the crop
     * region and output only the intersection rectangle as the metering region in the result
     * metadata.  If the region is entirely outside the crop region, it will be ignored and
     * not reported in the result metadata.</p>
     * <p><b>Units</b>: Pixel coordinates within {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}</p>
     * <p><b>Range of valid values:</b><br>
     * Coordinates must be between <code>[(0,0), (width, height))</code> of
     * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CameraCharacteristics#CONTROL_MAX_REGIONS_AE
     * @see CaptureRequest#SCALER_CROP_REGION
     * @see CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE
     */
    @PublicKey
    public static final Key<android.hardware.camera2.params.MeteringRectangle[]> CONTROL_AE_REGIONS =
            new Key<android.hardware.camera2.params.MeteringRectangle[]>("android.control.aeRegions", android.hardware.camera2.params.MeteringRectangle[].class);

    /**
     * <p>Range over which the auto-exposure routine can
     * adjust the capture frame rate to maintain good
     * exposure.</p>
     * <p>Only constrains auto-exposure (AE) algorithm, not
     * manual control of {@link CaptureRequest#SENSOR_EXPOSURE_TIME android.sensor.exposureTime} and
     * {@link CaptureRequest#SENSOR_FRAME_DURATION android.sensor.frameDuration}.</p>
     * <p><b>Units</b>: Frames per second (FPS)</p>
     * <p><b>Range of valid values:</b><br>
     * Any of the entries in {@link CameraCharacteristics#CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES android.control.aeAvailableTargetFpsRanges}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES
     * @see CaptureRequest#SENSOR_EXPOSURE_TIME
     * @see CaptureRequest#SENSOR_FRAME_DURATION
     */
    @PublicKey
    public static final Key<android.util.Range<Integer>> CONTROL_AE_TARGET_FPS_RANGE =
            new Key<android.util.Range<Integer>>("android.control.aeTargetFpsRange", new TypeReference<android.util.Range<Integer>>() {{ }});

    /**
     * <p>Whether the camera device will trigger a precapture
     * metering sequence when it processes this request.</p>
     * <p>This entry is normally set to IDLE, or is not
     * included at all in the request settings. When included and
     * set to START, the camera device will trigger the auto-exposure (AE)
     * precapture metering sequence.</p>
     * <p>When set to CANCEL, the camera device will cancel any active
     * precapture metering trigger, and return to its initial AE state.
     * If a precapture metering sequence is already completed, and the camera
     * device has implicitly locked the AE for subsequent still capture, the
     * CANCEL trigger will unlock the AE and return to its initial AE state.</p>
     * <p>The precapture sequence should be triggered before starting a
     * high-quality still capture for final metering decisions to
     * be made, and for firing pre-capture flash pulses to estimate
     * scene brightness and required final capture flash power, when
     * the flash is enabled.</p>
     * <p>Normally, this entry should be set to START for only a
     * single request, and the application should wait until the
     * sequence completes before starting a new one.</p>
     * <p>When a precapture metering sequence is finished, the camera device
     * may lock the auto-exposure routine internally to be able to accurately expose the
     * subsequent still capture image (<code>{@link CaptureRequest#CONTROL_CAPTURE_INTENT android.control.captureIntent} == STILL_CAPTURE</code>).
     * For this case, the AE may not resume normal scan if no subsequent still capture is
     * submitted. To ensure that the AE routine restarts normal scan, the application should
     * submit a request with <code>{@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} == true</code>, followed by a request
     * with <code>{@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} == false</code>, if the application decides not to submit a
     * still capture request after the precapture sequence completes. Alternatively, for
     * API level 23 or newer devices, the CANCEL can be used to unlock the camera device
     * internally locked AE if the application doesn't submit a still capture request after
     * the AE precapture trigger. Note that, the CANCEL was added in API level 23, and must not
     * be used in devices that have earlier API levels.</p>
     * <p>The exact effect of auto-exposure (AE) precapture trigger
     * depends on the current AE mode and state; see
     * {@link CaptureResult#CONTROL_AE_STATE android.control.aeState} for AE precapture state transition
     * details.</p>
     * <p>On LEGACY-level devices, the precapture trigger is not supported;
     * capturing a high-resolution JPEG image will automatically trigger a
     * precapture sequence before the high-resolution capture, including
     * potentially firing a pre-capture flash.</p>
     * <p>Using the precapture trigger and the auto-focus trigger {@link CaptureRequest#CONTROL_AF_TRIGGER android.control.afTrigger}
     * simultaneously is allowed. However, since these triggers often require cooperation between
     * the auto-focus and auto-exposure routines (for example, the may need to be enabled for a
     * focus sweep), the camera device may delay acting on a later trigger until the previous
     * trigger has been fully handled. This may lead to longer intervals between the trigger and
     * changes to {@link CaptureResult#CONTROL_AE_STATE android.control.aeState} indicating the start of the precapture sequence, for
     * example.</p>
     * <p>If both the precapture and the auto-focus trigger are activated on the same request, then
     * the camera device will complete them in the optimal order for that device.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_AE_PRECAPTURE_TRIGGER_IDLE IDLE}</li>
     *   <li>{@link #CONTROL_AE_PRECAPTURE_TRIGGER_START START}</li>
     *   <li>{@link #CONTROL_AE_PRECAPTURE_TRIGGER_CANCEL CANCEL}</li>
     * </ul></p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Limited capability</b> -
     * Present on all camera devices that report being at least {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED HARDWARE_LEVEL_LIMITED} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#CONTROL_AE_LOCK
     * @see CaptureResult#CONTROL_AE_STATE
     * @see CaptureRequest#CONTROL_AF_TRIGGER
     * @see CaptureRequest#CONTROL_CAPTURE_INTENT
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see #CONTROL_AE_PRECAPTURE_TRIGGER_IDLE
     * @see #CONTROL_AE_PRECAPTURE_TRIGGER_START
     * @see #CONTROL_AE_PRECAPTURE_TRIGGER_CANCEL
     */
    @PublicKey
    public static final Key<Integer> CONTROL_AE_PRECAPTURE_TRIGGER =
            new Key<Integer>("android.control.aePrecaptureTrigger", int.class);

    /**
     * <p>Current state of the auto-exposure (AE) algorithm.</p>
     * <p>Switching between or enabling AE modes ({@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode}) always
     * resets the AE state to INACTIVE. Similarly, switching between {@link CaptureRequest#CONTROL_MODE android.control.mode},
     * or {@link CaptureRequest#CONTROL_SCENE_MODE android.control.sceneMode} if <code>{@link CaptureRequest#CONTROL_MODE android.control.mode} == USE_SCENE_MODE</code> resets all
     * the algorithm states to INACTIVE.</p>
     * <p>The camera device can do several state transitions between two results, if it is
     * allowed by the state transition table. For example: INACTIVE may never actually be
     * seen in a result.</p>
     * <p>The state in the result is the state for this image (in sync with this image): if
     * AE state becomes CONVERGED, then the image data associated with this result should
     * be good to use.</p>
     * <p>Below are state transition tables for different AE modes.</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center"></td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Camera device auto exposure algorithm is disabled</td>
     * </tr>
     * </tbody>
     * </table>
     * <p>When {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} is AE_MODE_ON_*:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">Camera device initiates AE scan</td>
     * <td align="center">SEARCHING</td>
     * <td align="center">Values changing</td>
     * </tr>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} is ON</td>
     * <td align="center">LOCKED</td>
     * <td align="center">Values locked</td>
     * </tr>
     * <tr>
     * <td align="center">SEARCHING</td>
     * <td align="center">Camera device finishes AE scan</td>
     * <td align="center">CONVERGED</td>
     * <td align="center">Good values, not changing</td>
     * </tr>
     * <tr>
     * <td align="center">SEARCHING</td>
     * <td align="center">Camera device finishes AE scan</td>
     * <td align="center">FLASH_REQUIRED</td>
     * <td align="center">Converged but too dark w/o flash</td>
     * </tr>
     * <tr>
     * <td align="center">SEARCHING</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} is ON</td>
     * <td align="center">LOCKED</td>
     * <td align="center">Values locked</td>
     * </tr>
     * <tr>
     * <td align="center">CONVERGED</td>
     * <td align="center">Camera device initiates AE scan</td>
     * <td align="center">SEARCHING</td>
     * <td align="center">Values changing</td>
     * </tr>
     * <tr>
     * <td align="center">CONVERGED</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} is ON</td>
     * <td align="center">LOCKED</td>
     * <td align="center">Values locked</td>
     * </tr>
     * <tr>
     * <td align="center">FLASH_REQUIRED</td>
     * <td align="center">Camera device initiates AE scan</td>
     * <td align="center">SEARCHING</td>
     * <td align="center">Values changing</td>
     * </tr>
     * <tr>
     * <td align="center">FLASH_REQUIRED</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} is ON</td>
     * <td align="center">LOCKED</td>
     * <td align="center">Values locked</td>
     * </tr>
     * <tr>
     * <td align="center">LOCKED</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} is OFF</td>
     * <td align="center">SEARCHING</td>
     * <td align="center">Values not good after unlock</td>
     * </tr>
     * <tr>
     * <td align="center">LOCKED</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} is OFF</td>
     * <td align="center">CONVERGED</td>
     * <td align="center">Values good after unlock</td>
     * </tr>
     * <tr>
     * <td align="center">LOCKED</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} is OFF</td>
     * <td align="center">FLASH_REQUIRED</td>
     * <td align="center">Exposure good, but too dark</td>
     * </tr>
     * <tr>
     * <td align="center">PRECAPTURE</td>
     * <td align="center">Sequence done. {@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} is OFF</td>
     * <td align="center">CONVERGED</td>
     * <td align="center">Ready for high-quality capture</td>
     * </tr>
     * <tr>
     * <td align="center">PRECAPTURE</td>
     * <td align="center">Sequence done. {@link CaptureRequest#CONTROL_AE_LOCK android.control.aeLock} is ON</td>
     * <td align="center">LOCKED</td>
     * <td align="center">Ready for high-quality capture</td>
     * </tr>
     * <tr>
     * <td align="center">LOCKED</td>
     * <td align="center">aeLock is ON and aePrecaptureTrigger is START</td>
     * <td align="center">LOCKED</td>
     * <td align="center">Precapture trigger is ignored when AE is already locked</td>
     * </tr>
     * <tr>
     * <td align="center">LOCKED</td>
     * <td align="center">aeLock is ON and aePrecaptureTrigger is CANCEL</td>
     * <td align="center">LOCKED</td>
     * <td align="center">Precapture trigger is ignored when AE is already locked</td>
     * </tr>
     * <tr>
     * <td align="center">Any state (excluding LOCKED)</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER android.control.aePrecaptureTrigger} is START</td>
     * <td align="center">PRECAPTURE</td>
     * <td align="center">Start AE precapture metering sequence</td>
     * </tr>
     * <tr>
     * <td align="center">Any state (excluding LOCKED)</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER android.control.aePrecaptureTrigger} is CANCEL</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Currently active precapture metering sequence is canceled</td>
     * </tr>
     * </tbody>
     * </table>
     * <p>For the above table, the camera device may skip reporting any state changes that happen
     * without application intervention (i.e. mode switch, trigger, locking). Any state that
     * can be skipped in that manner is called a transient state.</p>
     * <p>For example, for above AE modes (AE_MODE_ON_*), in addition to the state transitions
     * listed in above table, it is also legal for the camera device to skip one or more
     * transient states between two results. See below table for examples:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">Camera device finished AE scan</td>
     * <td align="center">CONVERGED</td>
     * <td align="center">Values are already good, transient states are skipped by camera device.</td>
     * </tr>
     * <tr>
     * <td align="center">Any state (excluding LOCKED)</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER android.control.aePrecaptureTrigger} is START, sequence done</td>
     * <td align="center">FLASH_REQUIRED</td>
     * <td align="center">Converged but too dark w/o flash after a precapture sequence, transient states are skipped by camera device.</td>
     * </tr>
     * <tr>
     * <td align="center">Any state (excluding LOCKED)</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER android.control.aePrecaptureTrigger} is START, sequence done</td>
     * <td align="center">CONVERGED</td>
     * <td align="center">Converged after a precapture sequence, transient states are skipped by camera device.</td>
     * </tr>
     * <tr>
     * <td align="center">Any state (excluding LOCKED)</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER android.control.aePrecaptureTrigger} is CANCEL, converged</td>
     * <td align="center">FLASH_REQUIRED</td>
     * <td align="center">Converged but too dark w/o flash after a precapture sequence is canceled, transient states are skipped by camera device.</td>
     * </tr>
     * <tr>
     * <td align="center">Any state (excluding LOCKED)</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER android.control.aePrecaptureTrigger} is CANCEL, converged</td>
     * <td align="center">CONVERGED</td>
     * <td align="center">Converged after a precapture sequenceis canceled, transient states are skipped by camera device.</td>
     * </tr>
     * <tr>
     * <td align="center">CONVERGED</td>
     * <td align="center">Camera device finished AE scan</td>
     * <td align="center">FLASH_REQUIRED</td>
     * <td align="center">Converged but too dark w/o flash after a new scan, transient states are skipped by camera device.</td>
     * </tr>
     * <tr>
     * <td align="center">FLASH_REQUIRED</td>
     * <td align="center">Camera device finished AE scan</td>
     * <td align="center">CONVERGED</td>
     * <td align="center">Converged after a new scan, transient states are skipped by camera device.</td>
     * </tr>
     * </tbody>
     * </table>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_AE_STATE_INACTIVE INACTIVE}</li>
     *   <li>{@link #CONTROL_AE_STATE_SEARCHING SEARCHING}</li>
     *   <li>{@link #CONTROL_AE_STATE_CONVERGED CONVERGED}</li>
     *   <li>{@link #CONTROL_AE_STATE_LOCKED LOCKED}</li>
     *   <li>{@link #CONTROL_AE_STATE_FLASH_REQUIRED FLASH_REQUIRED}</li>
     *   <li>{@link #CONTROL_AE_STATE_PRECAPTURE PRECAPTURE}</li>
     * </ul></p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Limited capability</b> -
     * Present on all camera devices that report being at least {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED HARDWARE_LEVEL_LIMITED} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#CONTROL_AE_LOCK
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER
     * @see CaptureRequest#CONTROL_MODE
     * @see CaptureRequest#CONTROL_SCENE_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see #CONTROL_AE_STATE_INACTIVE
     * @see #CONTROL_AE_STATE_SEARCHING
     * @see #CONTROL_AE_STATE_CONVERGED
     * @see #CONTROL_AE_STATE_LOCKED
     * @see #CONTROL_AE_STATE_FLASH_REQUIRED
     * @see #CONTROL_AE_STATE_PRECAPTURE
     */
    @PublicKey
    public static final Key<Integer> CONTROL_AE_STATE =
            new Key<Integer>("android.control.aeState", int.class);

    /**
     * <p>Whether auto-focus (AF) is currently enabled, and what
     * mode it is set to.</p>
     * <p>Only effective if {@link CaptureRequest#CONTROL_MODE android.control.mode} = AUTO and the lens is not fixed focus
     * (i.e. <code>{@link CameraCharacteristics#LENS_INFO_MINIMUM_FOCUS_DISTANCE android.lens.info.minimumFocusDistance} &gt; 0</code>). Also note that
     * when {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} is OFF, the behavior of AF is device
     * dependent. It is recommended to lock AF by using {@link CaptureRequest#CONTROL_AF_TRIGGER android.control.afTrigger} before
     * setting {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} to OFF, or set AF mode to OFF when AE is OFF.</p>
     * <p>If the lens is controlled by the camera device auto-focus algorithm,
     * the camera device will report the current AF status in {@link CaptureResult#CONTROL_AF_STATE android.control.afState}
     * in result metadata.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_AF_MODE_OFF OFF}</li>
     *   <li>{@link #CONTROL_AF_MODE_AUTO AUTO}</li>
     *   <li>{@link #CONTROL_AF_MODE_MACRO MACRO}</li>
     *   <li>{@link #CONTROL_AF_MODE_CONTINUOUS_VIDEO CONTINUOUS_VIDEO}</li>
     *   <li>{@link #CONTROL_AF_MODE_CONTINUOUS_PICTURE CONTINUOUS_PICTURE}</li>
     *   <li>{@link #CONTROL_AF_MODE_EDOF EDOF}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#CONTROL_AF_AVAILABLE_MODES android.control.afAvailableModes}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CameraCharacteristics#CONTROL_AF_AVAILABLE_MODES
     * @see CaptureResult#CONTROL_AF_STATE
     * @see CaptureRequest#CONTROL_AF_TRIGGER
     * @see CaptureRequest#CONTROL_MODE
     * @see CameraCharacteristics#LENS_INFO_MINIMUM_FOCUS_DISTANCE
     * @see #CONTROL_AF_MODE_OFF
     * @see #CONTROL_AF_MODE_AUTO
     * @see #CONTROL_AF_MODE_MACRO
     * @see #CONTROL_AF_MODE_CONTINUOUS_VIDEO
     * @see #CONTROL_AF_MODE_CONTINUOUS_PICTURE
     * @see #CONTROL_AF_MODE_EDOF
     */
    @PublicKey
    public static final Key<Integer> CONTROL_AF_MODE =
            new Key<Integer>("android.control.afMode", int.class);

    /**
     * <p>List of metering areas to use for auto-focus.</p>
     * <p>Not available if {@link CameraCharacteristics#CONTROL_MAX_REGIONS_AF android.control.maxRegionsAf} is 0.
     * Otherwise will always be present.</p>
     * <p>The maximum number of focus areas supported by the device is determined by the value
     * of {@link CameraCharacteristics#CONTROL_MAX_REGIONS_AF android.control.maxRegionsAf}.</p>
     * <p>The coordinate system is based on the active pixel array,
     * with (0,0) being the top-left pixel in the active pixel array, and
     * ({@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}.width - 1,
     * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}.height - 1) being the
     * bottom-right pixel in the active pixel array.</p>
     * <p>The weight must be within <code>[0, 1000]</code>, and represents a weight
     * for every pixel in the area. This means that a large metering area
     * with the same weight as a smaller area will have more effect in
     * the metering result. Metering areas can partially overlap and the
     * camera device will add the weights in the overlap region.</p>
     * <p>The weights are relative to weights of other metering regions, so if only one region
     * is used, all non-zero weights will have the same effect. A region with 0 weight is
     * ignored.</p>
     * <p>If all regions have 0 weight, then no specific metering area needs to be used by the
     * camera device.</p>
     * <p>If the metering region is outside the used {@link CaptureRequest#SCALER_CROP_REGION android.scaler.cropRegion} returned in
     * capture result metadata, the camera device will ignore the sections outside the crop
     * region and output only the intersection rectangle as the metering region in the result
     * metadata. If the region is entirely outside the crop region, it will be ignored and
     * not reported in the result metadata.</p>
     * <p><b>Units</b>: Pixel coordinates within {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}</p>
     * <p><b>Range of valid values:</b><br>
     * Coordinates must be between <code>[(0,0), (width, height))</code> of
     * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CameraCharacteristics#CONTROL_MAX_REGIONS_AF
     * @see CaptureRequest#SCALER_CROP_REGION
     * @see CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE
     */
    @PublicKey
    public static final Key<android.hardware.camera2.params.MeteringRectangle[]> CONTROL_AF_REGIONS =
            new Key<android.hardware.camera2.params.MeteringRectangle[]>("android.control.afRegions", android.hardware.camera2.params.MeteringRectangle[].class);

    /**
     * <p>Whether the camera device will trigger autofocus for this request.</p>
     * <p>This entry is normally set to IDLE, or is not
     * included at all in the request settings.</p>
     * <p>When included and set to START, the camera device will trigger the
     * autofocus algorithm. If autofocus is disabled, this trigger has no effect.</p>
     * <p>When set to CANCEL, the camera device will cancel any active trigger,
     * and return to its initial AF state.</p>
     * <p>Generally, applications should set this entry to START or CANCEL for only a
     * single capture, and then return it to IDLE (or not set at all). Specifying
     * START for multiple captures in a row means restarting the AF operation over
     * and over again.</p>
     * <p>See {@link CaptureResult#CONTROL_AF_STATE android.control.afState} for what the trigger means for each AF mode.</p>
     * <p>Using the autofocus trigger and the precapture trigger {@link CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER android.control.aePrecaptureTrigger}
     * simultaneously is allowed. However, since these triggers often require cooperation between
     * the auto-focus and auto-exposure routines (for example, the may need to be enabled for a
     * focus sweep), the camera device may delay acting on a later trigger until the previous
     * trigger has been fully handled. This may lead to longer intervals between the trigger and
     * changes to {@link CaptureResult#CONTROL_AF_STATE android.control.afState}, for example.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_AF_TRIGGER_IDLE IDLE}</li>
     *   <li>{@link #CONTROL_AF_TRIGGER_START START}</li>
     *   <li>{@link #CONTROL_AF_TRIGGER_CANCEL CANCEL}</li>
     * </ul></p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER
     * @see CaptureResult#CONTROL_AF_STATE
     * @see #CONTROL_AF_TRIGGER_IDLE
     * @see #CONTROL_AF_TRIGGER_START
     * @see #CONTROL_AF_TRIGGER_CANCEL
     */
    @PublicKey
    public static final Key<Integer> CONTROL_AF_TRIGGER =
            new Key<Integer>("android.control.afTrigger", int.class);

    /**
     * <p>Current state of auto-focus (AF) algorithm.</p>
     * <p>Switching between or enabling AF modes ({@link CaptureRequest#CONTROL_AF_MODE android.control.afMode}) always
     * resets the AF state to INACTIVE. Similarly, switching between {@link CaptureRequest#CONTROL_MODE android.control.mode},
     * or {@link CaptureRequest#CONTROL_SCENE_MODE android.control.sceneMode} if <code>{@link CaptureRequest#CONTROL_MODE android.control.mode} == USE_SCENE_MODE</code> resets all
     * the algorithm states to INACTIVE.</p>
     * <p>The camera device can do several state transitions between two results, if it is
     * allowed by the state transition table. For example: INACTIVE may never actually be
     * seen in a result.</p>
     * <p>The state in the result is the state for this image (in sync with this image): if
     * AF state becomes FOCUSED, then the image data associated with this result should
     * be sharp.</p>
     * <p>Below are state transition tables for different AF modes.</p>
     * <p>When {@link CaptureRequest#CONTROL_AF_MODE android.control.afMode} is AF_MODE_OFF or AF_MODE_EDOF:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center"></td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Never changes</td>
     * </tr>
     * </tbody>
     * </table>
     * <p>When {@link CaptureRequest#CONTROL_AF_MODE android.control.afMode} is AF_MODE_AUTO or AF_MODE_MACRO:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">ACTIVE_SCAN</td>
     * <td align="center">Start AF sweep, Lens now moving</td>
     * </tr>
     * <tr>
     * <td align="center">ACTIVE_SCAN</td>
     * <td align="center">AF sweep done</td>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">Focused, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">ACTIVE_SCAN</td>
     * <td align="center">AF sweep done</td>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">Not focused, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">ACTIVE_SCAN</td>
     * <td align="center">AF_CANCEL</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Cancel/reset AF, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">AF_CANCEL</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Cancel/reset AF</td>
     * </tr>
     * <tr>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">ACTIVE_SCAN</td>
     * <td align="center">Start new sweep, Lens now moving</td>
     * </tr>
     * <tr>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">AF_CANCEL</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Cancel/reset AF</td>
     * </tr>
     * <tr>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">ACTIVE_SCAN</td>
     * <td align="center">Start new sweep, Lens now moving</td>
     * </tr>
     * <tr>
     * <td align="center">Any state</td>
     * <td align="center">Mode change</td>
     * <td align="center">INACTIVE</td>
     * <td align="center"></td>
     * </tr>
     * </tbody>
     * </table>
     * <p>For the above table, the camera device may skip reporting any state changes that happen
     * without application intervention (i.e. mode switch, trigger, locking). Any state that
     * can be skipped in that manner is called a transient state.</p>
     * <p>For example, for these AF modes (AF_MODE_AUTO and AF_MODE_MACRO), in addition to the
     * state transitions listed in above table, it is also legal for the camera device to skip
     * one or more transient states between two results. See below table for examples:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">Focus is already good or good after a scan, lens is now locked.</td>
     * </tr>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">Focus failed after a scan, lens is now locked.</td>
     * </tr>
     * <tr>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">Focus is already good or good after a scan, lens is now locked.</td>
     * </tr>
     * <tr>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">Focus is good after a scan, lens is not locked.</td>
     * </tr>
     * </tbody>
     * </table>
     * <p>When {@link CaptureRequest#CONTROL_AF_MODE android.control.afMode} is AF_MODE_CONTINUOUS_VIDEO:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">Camera device initiates new scan</td>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">Start AF scan, Lens now moving</td>
     * </tr>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">AF state query, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">Camera device completes current scan</td>
     * <td align="center">PASSIVE_FOCUSED</td>
     * <td align="center">End AF scan, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">Camera device fails current scan</td>
     * <td align="center">PASSIVE_UNFOCUSED</td>
     * <td align="center">End AF scan, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">Immediate transition, if focus is good. Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">Immediate transition, if focus is bad. Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">AF_CANCEL</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Reset lens position, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_FOCUSED</td>
     * <td align="center">Camera device initiates new scan</td>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">Start AF scan, Lens now moving</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_UNFOCUSED</td>
     * <td align="center">Camera device initiates new scan</td>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">Start AF scan, Lens now moving</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_FOCUSED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">Immediate transition, lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_UNFOCUSED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">Immediate transition, lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">No effect</td>
     * </tr>
     * <tr>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">AF_CANCEL</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Restart AF scan</td>
     * </tr>
     * <tr>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">No effect</td>
     * </tr>
     * <tr>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">AF_CANCEL</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Restart AF scan</td>
     * </tr>
     * </tbody>
     * </table>
     * <p>When {@link CaptureRequest#CONTROL_AF_MODE android.control.afMode} is AF_MODE_CONTINUOUS_PICTURE:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">Camera device initiates new scan</td>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">Start AF scan, Lens now moving</td>
     * </tr>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">AF state query, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">Camera device completes current scan</td>
     * <td align="center">PASSIVE_FOCUSED</td>
     * <td align="center">End AF scan, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">Camera device fails current scan</td>
     * <td align="center">PASSIVE_UNFOCUSED</td>
     * <td align="center">End AF scan, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">Eventual transition once the focus is good. Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">Eventual transition if cannot find focus. Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">AF_CANCEL</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Reset lens position, Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_FOCUSED</td>
     * <td align="center">Camera device initiates new scan</td>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">Start AF scan, Lens now moving</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_UNFOCUSED</td>
     * <td align="center">Camera device initiates new scan</td>
     * <td align="center">PASSIVE_SCAN</td>
     * <td align="center">Start AF scan, Lens now moving</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_FOCUSED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">Immediate trans. Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">PASSIVE_UNFOCUSED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">Immediate trans. Lens now locked</td>
     * </tr>
     * <tr>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">No effect</td>
     * </tr>
     * <tr>
     * <td align="center">FOCUSED_LOCKED</td>
     * <td align="center">AF_CANCEL</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Restart AF scan</td>
     * </tr>
     * <tr>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">AF_TRIGGER</td>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">No effect</td>
     * </tr>
     * <tr>
     * <td align="center">NOT_FOCUSED_LOCKED</td>
     * <td align="center">AF_CANCEL</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Restart AF scan</td>
     * </tr>
     * </tbody>
     * </table>
     * <p>When switch between AF_MODE_CONTINUOUS_* (CAF modes) and AF_MODE_AUTO/AF_MODE_MACRO
     * (AUTO modes), the initial INACTIVE or PASSIVE_SCAN states may be skipped by the
     * camera device. When a trigger is included in a mode switch request, the trigger
     * will be evaluated in the context of the new mode in the request.
     * See below table for examples:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">any state</td>
     * <td align="center">CAF--&gt;AUTO mode switch</td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Mode switch without trigger, initial state must be INACTIVE</td>
     * </tr>
     * <tr>
     * <td align="center">any state</td>
     * <td align="center">CAF--&gt;AUTO mode switch with AF_TRIGGER</td>
     * <td align="center">trigger-reachable states from INACTIVE</td>
     * <td align="center">Mode switch with trigger, INACTIVE is skipped</td>
     * </tr>
     * <tr>
     * <td align="center">any state</td>
     * <td align="center">AUTO--&gt;CAF mode switch</td>
     * <td align="center">passively reachable states from INACTIVE</td>
     * <td align="center">Mode switch without trigger, passive transient state is skipped</td>
     * </tr>
     * </tbody>
     * </table>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_AF_STATE_INACTIVE INACTIVE}</li>
     *   <li>{@link #CONTROL_AF_STATE_PASSIVE_SCAN PASSIVE_SCAN}</li>
     *   <li>{@link #CONTROL_AF_STATE_PASSIVE_FOCUSED PASSIVE_FOCUSED}</li>
     *   <li>{@link #CONTROL_AF_STATE_ACTIVE_SCAN ACTIVE_SCAN}</li>
     *   <li>{@link #CONTROL_AF_STATE_FOCUSED_LOCKED FOCUSED_LOCKED}</li>
     *   <li>{@link #CONTROL_AF_STATE_NOT_FOCUSED_LOCKED NOT_FOCUSED_LOCKED}</li>
     *   <li>{@link #CONTROL_AF_STATE_PASSIVE_UNFOCUSED PASSIVE_UNFOCUSED}</li>
     * </ul></p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#CONTROL_AF_MODE
     * @see CaptureRequest#CONTROL_MODE
     * @see CaptureRequest#CONTROL_SCENE_MODE
     * @see #CONTROL_AF_STATE_INACTIVE
     * @see #CONTROL_AF_STATE_PASSIVE_SCAN
     * @see #CONTROL_AF_STATE_PASSIVE_FOCUSED
     * @see #CONTROL_AF_STATE_ACTIVE_SCAN
     * @see #CONTROL_AF_STATE_FOCUSED_LOCKED
     * @see #CONTROL_AF_STATE_NOT_FOCUSED_LOCKED
     * @see #CONTROL_AF_STATE_PASSIVE_UNFOCUSED
     */
    @PublicKey
    public static final Key<Integer> CONTROL_AF_STATE =
            new Key<Integer>("android.control.afState", int.class);

    /**
     * <p>Whether auto-white balance (AWB) is currently locked to its
     * latest calculated values.</p>
     * <p>When set to <code>true</code> (ON), the AWB algorithm is locked to its latest parameters,
     * and will not change color balance settings until the lock is set to <code>false</code> (OFF).</p>
     * <p>Since the camera device has a pipeline of in-flight requests, the settings that
     * get locked do not necessarily correspond to the settings that were present in the
     * latest capture result received from the camera device, since additional captures
     * and AWB updates may have occurred even before the result was sent out. If an
     * application is switching between automatic and manual control and wishes to eliminate
     * any flicker during the switch, the following procedure is recommended:</p>
     * <ol>
     * <li>Starting in auto-AWB mode:</li>
     * <li>Lock AWB</li>
     * <li>Wait for the first result to be output that has the AWB locked</li>
     * <li>Copy AWB settings from that result into a request, set the request to manual AWB</li>
     * <li>Submit the capture request, proceed to run manual AWB as desired.</li>
     * </ol>
     * <p>Note that AWB lock is only meaningful when
     * {@link CaptureRequest#CONTROL_AWB_MODE android.control.awbMode} is in the AUTO mode; in other modes,
     * AWB is already fixed to a specific setting.</p>
     * <p>Some LEGACY devices may not support ON; the value is then overridden to OFF.</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#CONTROL_AWB_MODE
     */
    @PublicKey
    public static final Key<Boolean> CONTROL_AWB_LOCK =
            new Key<Boolean>("android.control.awbLock", boolean.class);

    /**
     * <p>Whether auto-white balance (AWB) is currently setting the color
     * transform fields, and what its illumination target
     * is.</p>
     * <p>This control is only effective if {@link CaptureRequest#CONTROL_MODE android.control.mode} is AUTO.</p>
     * <p>When set to the ON mode, the camera device's auto-white balance
     * routine is enabled, overriding the application's selected
     * {@link CaptureRequest#COLOR_CORRECTION_TRANSFORM android.colorCorrection.transform}, {@link CaptureRequest#COLOR_CORRECTION_GAINS android.colorCorrection.gains} and
     * {@link CaptureRequest#COLOR_CORRECTION_MODE android.colorCorrection.mode}. Note that when {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode}
     * is OFF, the behavior of AWB is device dependent. It is recommened to
     * also set AWB mode to OFF or lock AWB by using {@link CaptureRequest#CONTROL_AWB_LOCK android.control.awbLock} before
     * setting AE mode to OFF.</p>
     * <p>When set to the OFF mode, the camera device's auto-white balance
     * routine is disabled. The application manually controls the white
     * balance by {@link CaptureRequest#COLOR_CORRECTION_TRANSFORM android.colorCorrection.transform}, {@link CaptureRequest#COLOR_CORRECTION_GAINS android.colorCorrection.gains}
     * and {@link CaptureRequest#COLOR_CORRECTION_MODE android.colorCorrection.mode}.</p>
     * <p>When set to any other modes, the camera device's auto-white
     * balance routine is disabled. The camera device uses each
     * particular illumination target for white balance
     * adjustment. The application's values for
     * {@link CaptureRequest#COLOR_CORRECTION_TRANSFORM android.colorCorrection.transform},
     * {@link CaptureRequest#COLOR_CORRECTION_GAINS android.colorCorrection.gains} and
     * {@link CaptureRequest#COLOR_CORRECTION_MODE android.colorCorrection.mode} are ignored.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_AWB_MODE_OFF OFF}</li>
     *   <li>{@link #CONTROL_AWB_MODE_AUTO AUTO}</li>
     *   <li>{@link #CONTROL_AWB_MODE_INCANDESCENT INCANDESCENT}</li>
     *   <li>{@link #CONTROL_AWB_MODE_FLUORESCENT FLUORESCENT}</li>
     *   <li>{@link #CONTROL_AWB_MODE_WARM_FLUORESCENT WARM_FLUORESCENT}</li>
     *   <li>{@link #CONTROL_AWB_MODE_DAYLIGHT DAYLIGHT}</li>
     *   <li>{@link #CONTROL_AWB_MODE_CLOUDY_DAYLIGHT CLOUDY_DAYLIGHT}</li>
     *   <li>{@link #CONTROL_AWB_MODE_TWILIGHT TWILIGHT}</li>
     *   <li>{@link #CONTROL_AWB_MODE_SHADE SHADE}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#CONTROL_AWB_AVAILABLE_MODES android.control.awbAvailableModes}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#COLOR_CORRECTION_GAINS
     * @see CaptureRequest#COLOR_CORRECTION_MODE
     * @see CaptureRequest#COLOR_CORRECTION_TRANSFORM
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CameraCharacteristics#CONTROL_AWB_AVAILABLE_MODES
     * @see CaptureRequest#CONTROL_AWB_LOCK
     * @see CaptureRequest#CONTROL_MODE
     * @see #CONTROL_AWB_MODE_OFF
     * @see #CONTROL_AWB_MODE_AUTO
     * @see #CONTROL_AWB_MODE_INCANDESCENT
     * @see #CONTROL_AWB_MODE_FLUORESCENT
     * @see #CONTROL_AWB_MODE_WARM_FLUORESCENT
     * @see #CONTROL_AWB_MODE_DAYLIGHT
     * @see #CONTROL_AWB_MODE_CLOUDY_DAYLIGHT
     * @see #CONTROL_AWB_MODE_TWILIGHT
     * @see #CONTROL_AWB_MODE_SHADE
     */
    @PublicKey
    public static final Key<Integer> CONTROL_AWB_MODE =
            new Key<Integer>("android.control.awbMode", int.class);

    /**
     * <p>List of metering areas to use for auto-white-balance illuminant
     * estimation.</p>
     * <p>Not available if {@link CameraCharacteristics#CONTROL_MAX_REGIONS_AWB android.control.maxRegionsAwb} is 0.
     * Otherwise will always be present.</p>
     * <p>The maximum number of regions supported by the device is determined by the value
     * of {@link CameraCharacteristics#CONTROL_MAX_REGIONS_AWB android.control.maxRegionsAwb}.</p>
     * <p>The coordinate system is based on the active pixel array,
     * with (0,0) being the top-left pixel in the active pixel array, and
     * ({@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}.width - 1,
     * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}.height - 1) being the
     * bottom-right pixel in the active pixel array.</p>
     * <p>The weight must range from 0 to 1000, and represents a weight
     * for every pixel in the area. This means that a large metering area
     * with the same weight as a smaller area will have more effect in
     * the metering result. Metering areas can partially overlap and the
     * camera device will add the weights in the overlap region.</p>
     * <p>The weights are relative to weights of other white balance metering regions, so if
     * only one region is used, all non-zero weights will have the same effect. A region with
     * 0 weight is ignored.</p>
     * <p>If all regions have 0 weight, then no specific metering area needs to be used by the
     * camera device.</p>
     * <p>If the metering region is outside the used {@link CaptureRequest#SCALER_CROP_REGION android.scaler.cropRegion} returned in
     * capture result metadata, the camera device will ignore the sections outside the crop
     * region and output only the intersection rectangle as the metering region in the result
     * metadata.  If the region is entirely outside the crop region, it will be ignored and
     * not reported in the result metadata.</p>
     * <p><b>Units</b>: Pixel coordinates within {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}</p>
     * <p><b>Range of valid values:</b><br>
     * Coordinates must be between <code>[(0,0), (width, height))</code> of
     * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CameraCharacteristics#CONTROL_MAX_REGIONS_AWB
     * @see CaptureRequest#SCALER_CROP_REGION
     * @see CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE
     */
    @PublicKey
    public static final Key<android.hardware.camera2.params.MeteringRectangle[]> CONTROL_AWB_REGIONS =
            new Key<android.hardware.camera2.params.MeteringRectangle[]>("android.control.awbRegions", android.hardware.camera2.params.MeteringRectangle[].class);

    /**
     * <p>Information to the camera device 3A (auto-exposure,
     * auto-focus, auto-white balance) routines about the purpose
     * of this capture, to help the camera device to decide optimal 3A
     * strategy.</p>
     * <p>This control (except for MANUAL) is only effective if
     * <code>{@link CaptureRequest#CONTROL_MODE android.control.mode} != OFF</code> and any 3A routine is active.</p>
     * <p>ZERO_SHUTTER_LAG will be supported if {@link CameraCharacteristics#REQUEST_AVAILABLE_CAPABILITIES android.request.availableCapabilities}
     * contains PRIVATE_REPROCESSING or YUV_REPROCESSING. MANUAL will be supported if
     * {@link CameraCharacteristics#REQUEST_AVAILABLE_CAPABILITIES android.request.availableCapabilities} contains MANUAL_SENSOR. Other intent values are
     * always supported.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_CAPTURE_INTENT_CUSTOM CUSTOM}</li>
     *   <li>{@link #CONTROL_CAPTURE_INTENT_PREVIEW PREVIEW}</li>
     *   <li>{@link #CONTROL_CAPTURE_INTENT_STILL_CAPTURE STILL_CAPTURE}</li>
     *   <li>{@link #CONTROL_CAPTURE_INTENT_VIDEO_RECORD VIDEO_RECORD}</li>
     *   <li>{@link #CONTROL_CAPTURE_INTENT_VIDEO_SNAPSHOT VIDEO_SNAPSHOT}</li>
     *   <li>{@link #CONTROL_CAPTURE_INTENT_ZERO_SHUTTER_LAG ZERO_SHUTTER_LAG}</li>
     *   <li>{@link #CONTROL_CAPTURE_INTENT_MANUAL MANUAL}</li>
     * </ul></p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#CONTROL_MODE
     * @see CameraCharacteristics#REQUEST_AVAILABLE_CAPABILITIES
     * @see #CONTROL_CAPTURE_INTENT_CUSTOM
     * @see #CONTROL_CAPTURE_INTENT_PREVIEW
     * @see #CONTROL_CAPTURE_INTENT_STILL_CAPTURE
     * @see #CONTROL_CAPTURE_INTENT_VIDEO_RECORD
     * @see #CONTROL_CAPTURE_INTENT_VIDEO_SNAPSHOT
     * @see #CONTROL_CAPTURE_INTENT_ZERO_SHUTTER_LAG
     * @see #CONTROL_CAPTURE_INTENT_MANUAL
     */
    @PublicKey
    public static final Key<Integer> CONTROL_CAPTURE_INTENT =
            new Key<Integer>("android.control.captureIntent", int.class);

    /**
     * <p>Current state of auto-white balance (AWB) algorithm.</p>
     * <p>Switching between or enabling AWB modes ({@link CaptureRequest#CONTROL_AWB_MODE android.control.awbMode}) always
     * resets the AWB state to INACTIVE. Similarly, switching between {@link CaptureRequest#CONTROL_MODE android.control.mode},
     * or {@link CaptureRequest#CONTROL_SCENE_MODE android.control.sceneMode} if <code>{@link CaptureRequest#CONTROL_MODE android.control.mode} == USE_SCENE_MODE</code> resets all
     * the algorithm states to INACTIVE.</p>
     * <p>The camera device can do several state transitions between two results, if it is
     * allowed by the state transition table. So INACTIVE may never actually be seen in
     * a result.</p>
     * <p>The state in the result is the state for this image (in sync with this image): if
     * AWB state becomes CONVERGED, then the image data associated with this result should
     * be good to use.</p>
     * <p>Below are state transition tables for different AWB modes.</p>
     * <p>When <code>{@link CaptureRequest#CONTROL_AWB_MODE android.control.awbMode} != AWB_MODE_AUTO</code>:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center"></td>
     * <td align="center">INACTIVE</td>
     * <td align="center">Camera device auto white balance algorithm is disabled</td>
     * </tr>
     * </tbody>
     * </table>
     * <p>When {@link CaptureRequest#CONTROL_AWB_MODE android.control.awbMode} is AWB_MODE_AUTO:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">Camera device initiates AWB scan</td>
     * <td align="center">SEARCHING</td>
     * <td align="center">Values changing</td>
     * </tr>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AWB_LOCK android.control.awbLock} is ON</td>
     * <td align="center">LOCKED</td>
     * <td align="center">Values locked</td>
     * </tr>
     * <tr>
     * <td align="center">SEARCHING</td>
     * <td align="center">Camera device finishes AWB scan</td>
     * <td align="center">CONVERGED</td>
     * <td align="center">Good values, not changing</td>
     * </tr>
     * <tr>
     * <td align="center">SEARCHING</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AWB_LOCK android.control.awbLock} is ON</td>
     * <td align="center">LOCKED</td>
     * <td align="center">Values locked</td>
     * </tr>
     * <tr>
     * <td align="center">CONVERGED</td>
     * <td align="center">Camera device initiates AWB scan</td>
     * <td align="center">SEARCHING</td>
     * <td align="center">Values changing</td>
     * </tr>
     * <tr>
     * <td align="center">CONVERGED</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AWB_LOCK android.control.awbLock} is ON</td>
     * <td align="center">LOCKED</td>
     * <td align="center">Values locked</td>
     * </tr>
     * <tr>
     * <td align="center">LOCKED</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AWB_LOCK android.control.awbLock} is OFF</td>
     * <td align="center">SEARCHING</td>
     * <td align="center">Values not good after unlock</td>
     * </tr>
     * </tbody>
     * </table>
     * <p>For the above table, the camera device may skip reporting any state changes that happen
     * without application intervention (i.e. mode switch, trigger, locking). Any state that
     * can be skipped in that manner is called a transient state.</p>
     * <p>For example, for this AWB mode (AWB_MODE_AUTO), in addition to the state transitions
     * listed in above table, it is also legal for the camera device to skip one or more
     * transient states between two results. See below table for examples:</p>
     * <table>
     * <thead>
     * <tr>
     * <th align="center">State</th>
     * <th align="center">Transition Cause</th>
     * <th align="center">New State</th>
     * <th align="center">Notes</th>
     * </tr>
     * </thead>
     * <tbody>
     * <tr>
     * <td align="center">INACTIVE</td>
     * <td align="center">Camera device finished AWB scan</td>
     * <td align="center">CONVERGED</td>
     * <td align="center">Values are already good, transient states are skipped by camera device.</td>
     * </tr>
     * <tr>
     * <td align="center">LOCKED</td>
     * <td align="center">{@link CaptureRequest#CONTROL_AWB_LOCK android.control.awbLock} is OFF</td>
     * <td align="center">CONVERGED</td>
     * <td align="center">Values good after unlock, transient states are skipped by camera device.</td>
     * </tr>
     * </tbody>
     * </table>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_AWB_STATE_INACTIVE INACTIVE}</li>
     *   <li>{@link #CONTROL_AWB_STATE_SEARCHING SEARCHING}</li>
     *   <li>{@link #CONTROL_AWB_STATE_CONVERGED CONVERGED}</li>
     *   <li>{@link #CONTROL_AWB_STATE_LOCKED LOCKED}</li>
     * </ul></p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Limited capability</b> -
     * Present on all camera devices that report being at least {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED HARDWARE_LEVEL_LIMITED} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#CONTROL_AWB_LOCK
     * @see CaptureRequest#CONTROL_AWB_MODE
     * @see CaptureRequest#CONTROL_MODE
     * @see CaptureRequest#CONTROL_SCENE_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see #CONTROL_AWB_STATE_INACTIVE
     * @see #CONTROL_AWB_STATE_SEARCHING
     * @see #CONTROL_AWB_STATE_CONVERGED
     * @see #CONTROL_AWB_STATE_LOCKED
     */
    @PublicKey
    public static final Key<Integer> CONTROL_AWB_STATE =
            new Key<Integer>("android.control.awbState", int.class);

    /**
     * <p>A special color effect to apply.</p>
     * <p>When this mode is set, a color effect will be applied
     * to images produced by the camera device. The interpretation
     * and implementation of these color effects is left to the
     * implementor of the camera device, and should not be
     * depended on to be consistent (or present) across all
     * devices.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_EFFECT_MODE_OFF OFF}</li>
     *   <li>{@link #CONTROL_EFFECT_MODE_MONO MONO}</li>
     *   <li>{@link #CONTROL_EFFECT_MODE_NEGATIVE NEGATIVE}</li>
     *   <li>{@link #CONTROL_EFFECT_MODE_SOLARIZE SOLARIZE}</li>
     *   <li>{@link #CONTROL_EFFECT_MODE_SEPIA SEPIA}</li>
     *   <li>{@link #CONTROL_EFFECT_MODE_POSTERIZE POSTERIZE}</li>
     *   <li>{@link #CONTROL_EFFECT_MODE_WHITEBOARD WHITEBOARD}</li>
     *   <li>{@link #CONTROL_EFFECT_MODE_BLACKBOARD BLACKBOARD}</li>
     *   <li>{@link #CONTROL_EFFECT_MODE_AQUA AQUA}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#CONTROL_AVAILABLE_EFFECTS android.control.availableEffects}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#CONTROL_AVAILABLE_EFFECTS
     * @see #CONTROL_EFFECT_MODE_OFF
     * @see #CONTROL_EFFECT_MODE_MONO
     * @see #CONTROL_EFFECT_MODE_NEGATIVE
     * @see #CONTROL_EFFECT_MODE_SOLARIZE
     * @see #CONTROL_EFFECT_MODE_SEPIA
     * @see #CONTROL_EFFECT_MODE_POSTERIZE
     * @see #CONTROL_EFFECT_MODE_WHITEBOARD
     * @see #CONTROL_EFFECT_MODE_BLACKBOARD
     * @see #CONTROL_EFFECT_MODE_AQUA
     */
    @PublicKey
    public static final Key<Integer> CONTROL_EFFECT_MODE =
            new Key<Integer>("android.control.effectMode", int.class);

    /**
     * <p>Overall mode of 3A (auto-exposure, auto-white-balance, auto-focus) control
     * routines.</p>
     * <p>This is a top-level 3A control switch. When set to OFF, all 3A control
     * by the camera device is disabled. The application must set the fields for
     * capture parameters itself.</p>
     * <p>When set to AUTO, the individual algorithm controls in
     * android.control.* are in effect, such as {@link CaptureRequest#CONTROL_AF_MODE android.control.afMode}.</p>
     * <p>When set to USE_SCENE_MODE, the individual controls in
     * android.control.* are mostly disabled, and the camera device implements
     * one of the scene mode settings (such as ACTION, SUNSET, or PARTY)
     * as it wishes. The camera device scene mode 3A settings are provided by
     * {@link android.hardware.camera2.CaptureResult capture results}.</p>
     * <p>When set to OFF_KEEP_STATE, it is similar to OFF mode, the only difference
     * is that this frame will not be used by camera device background 3A statistics
     * update, as if this frame is never captured. This mode can be used in the scenario
     * where the application doesn't want a 3A manual control capture to affect
     * the subsequent auto 3A capture results.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_MODE_OFF OFF}</li>
     *   <li>{@link #CONTROL_MODE_AUTO AUTO}</li>
     *   <li>{@link #CONTROL_MODE_USE_SCENE_MODE USE_SCENE_MODE}</li>
     *   <li>{@link #CONTROL_MODE_OFF_KEEP_STATE OFF_KEEP_STATE}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#CONTROL_AVAILABLE_MODES android.control.availableModes}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#CONTROL_AF_MODE
     * @see CameraCharacteristics#CONTROL_AVAILABLE_MODES
     * @see #CONTROL_MODE_OFF
     * @see #CONTROL_MODE_AUTO
     * @see #CONTROL_MODE_USE_SCENE_MODE
     * @see #CONTROL_MODE_OFF_KEEP_STATE
     */
    @PublicKey
    public static final Key<Integer> CONTROL_MODE =
            new Key<Integer>("android.control.mode", int.class);

    /**
     * <p>Control for which scene mode is currently active.</p>
     * <p>Scene modes are custom camera modes optimized for a certain set of conditions and
     * capture settings.</p>
     * <p>This is the mode that that is active when
     * <code>{@link CaptureRequest#CONTROL_MODE android.control.mode} == USE_SCENE_MODE</code>. Aside from FACE_PRIORITY, these modes will
     * disable {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode}, {@link CaptureRequest#CONTROL_AWB_MODE android.control.awbMode}, and {@link CaptureRequest#CONTROL_AF_MODE android.control.afMode}
     * while in use.</p>
     * <p>The interpretation and implementation of these scene modes is left
     * to the implementor of the camera device. Their behavior will not be
     * consistent across all devices, and any given device may only implement
     * a subset of these modes.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_SCENE_MODE_DISABLED DISABLED}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_FACE_PRIORITY FACE_PRIORITY}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_ACTION ACTION}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_PORTRAIT PORTRAIT}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_LANDSCAPE LANDSCAPE}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_NIGHT NIGHT}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_NIGHT_PORTRAIT NIGHT_PORTRAIT}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_THEATRE THEATRE}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_BEACH BEACH}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_SNOW SNOW}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_SUNSET SUNSET}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_STEADYPHOTO STEADYPHOTO}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_FIREWORKS FIREWORKS}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_SPORTS SPORTS}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_PARTY PARTY}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_CANDLELIGHT CANDLELIGHT}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_BARCODE BARCODE}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_HIGH_SPEED_VIDEO HIGH_SPEED_VIDEO}</li>
     *   <li>{@link #CONTROL_SCENE_MODE_HDR HDR}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#CONTROL_AVAILABLE_SCENE_MODES android.control.availableSceneModes}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CaptureRequest#CONTROL_AF_MODE
     * @see CameraCharacteristics#CONTROL_AVAILABLE_SCENE_MODES
     * @see CaptureRequest#CONTROL_AWB_MODE
     * @see CaptureRequest#CONTROL_MODE
     * @see #CONTROL_SCENE_MODE_DISABLED
     * @see #CONTROL_SCENE_MODE_FACE_PRIORITY
     * @see #CONTROL_SCENE_MODE_ACTION
     * @see #CONTROL_SCENE_MODE_PORTRAIT
     * @see #CONTROL_SCENE_MODE_LANDSCAPE
     * @see #CONTROL_SCENE_MODE_NIGHT
     * @see #CONTROL_SCENE_MODE_NIGHT_PORTRAIT
     * @see #CONTROL_SCENE_MODE_THEATRE
     * @see #CONTROL_SCENE_MODE_BEACH
     * @see #CONTROL_SCENE_MODE_SNOW
     * @see #CONTROL_SCENE_MODE_SUNSET
     * @see #CONTROL_SCENE_MODE_STEADYPHOTO
     * @see #CONTROL_SCENE_MODE_FIREWORKS
     * @see #CONTROL_SCENE_MODE_SPORTS
     * @see #CONTROL_SCENE_MODE_PARTY
     * @see #CONTROL_SCENE_MODE_CANDLELIGHT
     * @see #CONTROL_SCENE_MODE_BARCODE
     * @see #CONTROL_SCENE_MODE_HIGH_SPEED_VIDEO
     * @see #CONTROL_SCENE_MODE_HDR
     */
    @PublicKey
    public static final Key<Integer> CONTROL_SCENE_MODE =
            new Key<Integer>("android.control.sceneMode", int.class);

    /**
     * <p>Whether video stabilization is
     * active.</p>
     * <p>Video stabilization automatically warps images from
     * the camera in order to stabilize motion between consecutive frames.</p>
     * <p>If enabled, video stabilization can modify the
     * {@link CaptureRequest#SCALER_CROP_REGION android.scaler.cropRegion} to keep the video stream stabilized.</p>
     * <p>Switching between different video stabilization modes may take several
     * frames to initialize, the camera device will report the current mode
     * in capture result metadata. For example, When "ON" mode is requested,
     * the video stabilization modes in the first several capture results may
     * still be "OFF", and it will become "ON" when the initialization is
     * done.</p>
     * <p>In addition, not all recording sizes or frame rates may be supported for
     * stabilization by a device that reports stabilization support. It is guaranteed
     * that an output targeting a MediaRecorder or MediaCodec will be stabilized if
     * the recording resolution is less than or equal to 1920 x 1080 (width less than
     * or equal to 1920, height less than or equal to 1080), and the recording
     * frame rate is less than or equal to 30fps.  At other sizes, the CaptureResult
     * {@link CaptureRequest#CONTROL_VIDEO_STABILIZATION_MODE android.control.videoStabilizationMode} field will return
     * OFF if the recording output is not stabilized, or if there are no output
     * Surface types that can be stabilized.</p>
     * <p>If a camera device supports both this mode and OIS
     * ({@link CaptureRequest#LENS_OPTICAL_STABILIZATION_MODE android.lens.opticalStabilizationMode}), turning both modes on may
     * produce undesirable interaction, so it is recommended not to enable
     * both at the same time.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #CONTROL_VIDEO_STABILIZATION_MODE_OFF OFF}</li>
     *   <li>{@link #CONTROL_VIDEO_STABILIZATION_MODE_ON ON}</li>
     * </ul></p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#CONTROL_VIDEO_STABILIZATION_MODE
     * @see CaptureRequest#LENS_OPTICAL_STABILIZATION_MODE
     * @see CaptureRequest#SCALER_CROP_REGION
     * @see #CONTROL_VIDEO_STABILIZATION_MODE_OFF
     * @see #CONTROL_VIDEO_STABILIZATION_MODE_ON
     */
    @PublicKey
    public static final Key<Integer> CONTROL_VIDEO_STABILIZATION_MODE =
            new Key<Integer>("android.control.videoStabilizationMode", int.class);

    /**
     * <p>Operation mode for edge
     * enhancement.</p>
     * <p>Edge enhancement improves sharpness and details in the captured image. OFF means
     * no enhancement will be applied by the camera device.</p>
     * <p>FAST/HIGH_QUALITY both mean camera device determined enhancement
     * will be applied. HIGH_QUALITY mode indicates that the
     * camera device will use the highest-quality enhancement algorithms,
     * even if it slows down capture rate. FAST means the camera device will
     * not slow down capture rate when applying edge enhancement. FAST may be the same as OFF if
     * edge enhancement will slow down capture rate. Every output stream will have a similar
     * amount of enhancement applied.</p>
     * <p>ZERO_SHUTTER_LAG is meant to be used by applications that maintain a continuous circular
     * buffer of high-resolution images during preview and reprocess image(s) from that buffer
     * into a final capture when triggered by the user. In this mode, the camera device applies
     * edge enhancement to low-resolution streams (below maximum recording resolution) to
     * maximize preview quality, but does not apply edge enhancement to high-resolution streams,
     * since those will be reprocessed later if necessary.</p>
     * <p>For YUV_REPROCESSING, these FAST/HIGH_QUALITY modes both mean that the camera
     * device will apply FAST/HIGH_QUALITY YUV-domain edge enhancement, respectively.
     * The camera device may adjust its internal edge enhancement parameters for best
     * image quality based on the {@link CaptureRequest#REPROCESS_EFFECTIVE_EXPOSURE_FACTOR android.reprocess.effectiveExposureFactor}, if it is set.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #EDGE_MODE_OFF OFF}</li>
     *   <li>{@link #EDGE_MODE_FAST FAST}</li>
     *   <li>{@link #EDGE_MODE_HIGH_QUALITY HIGH_QUALITY}</li>
     *   <li>{@link #EDGE_MODE_ZERO_SHUTTER_LAG ZERO_SHUTTER_LAG}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#EDGE_AVAILABLE_EDGE_MODES android.edge.availableEdgeModes}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#EDGE_AVAILABLE_EDGE_MODES
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CaptureRequest#REPROCESS_EFFECTIVE_EXPOSURE_FACTOR
     * @see #EDGE_MODE_OFF
     * @see #EDGE_MODE_FAST
     * @see #EDGE_MODE_HIGH_QUALITY
     * @see #EDGE_MODE_ZERO_SHUTTER_LAG
     */
    @PublicKey
    public static final Key<Integer> EDGE_MODE =
            new Key<Integer>("android.edge.mode", int.class);

    /**
     * <p>The desired mode for for the camera device's flash control.</p>
     * <p>This control is only effective when flash unit is available
     * (<code>{@link CameraCharacteristics#FLASH_INFO_AVAILABLE android.flash.info.available} == true</code>).</p>
     * <p>When this control is used, the {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} must be set to ON or OFF.
     * Otherwise, the camera device auto-exposure related flash control (ON_AUTO_FLASH,
     * ON_ALWAYS_FLASH, or ON_AUTO_FLASH_REDEYE) will override this control.</p>
     * <p>When set to OFF, the camera device will not fire flash for this capture.</p>
     * <p>When set to SINGLE, the camera device will fire flash regardless of the camera
     * device's auto-exposure routine's result. When used in still capture case, this
     * control should be used along with auto-exposure (AE) precapture metering sequence
     * ({@link CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER android.control.aePrecaptureTrigger}), otherwise, the image may be incorrectly exposed.</p>
     * <p>When set to TORCH, the flash will be on continuously. This mode can be used
     * for use cases such as preview, auto-focus assist, still capture, or video recording.</p>
     * <p>The flash status will be reported by {@link CaptureResult#FLASH_STATE android.flash.state} in the capture result metadata.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #FLASH_MODE_OFF OFF}</li>
     *   <li>{@link #FLASH_MODE_SINGLE SINGLE}</li>
     *   <li>{@link #FLASH_MODE_TORCH TORCH}</li>
     * </ul></p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CaptureRequest#CONTROL_AE_PRECAPTURE_TRIGGER
     * @see CameraCharacteristics#FLASH_INFO_AVAILABLE
     * @see CaptureResult#FLASH_STATE
     * @see #FLASH_MODE_OFF
     * @see #FLASH_MODE_SINGLE
     * @see #FLASH_MODE_TORCH
     */
    @PublicKey
    public static final Key<Integer> FLASH_MODE =
            new Key<Integer>("android.flash.mode", int.class);

    /**
     * <p>Current state of the flash
     * unit.</p>
     * <p>When the camera device doesn't have flash unit
     * (i.e. <code>{@link CameraCharacteristics#FLASH_INFO_AVAILABLE android.flash.info.available} == false</code>), this state will always be UNAVAILABLE.
     * Other states indicate the current flash status.</p>
     * <p>In certain conditions, this will be available on LEGACY devices:</p>
     * <ul>
     * <li>Flash-less cameras always return UNAVAILABLE.</li>
     * <li>Using {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} <code>==</code> ON_ALWAYS_FLASH
     *    will always return FIRED.</li>
     * <li>Using {@link CaptureRequest#FLASH_MODE android.flash.mode} <code>==</code> TORCH
     *    will always return FIRED.</li>
     * </ul>
     * <p>In all other conditions the state will not be available on
     * LEGACY devices (i.e. it will be <code>null</code>).</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #FLASH_STATE_UNAVAILABLE UNAVAILABLE}</li>
     *   <li>{@link #FLASH_STATE_CHARGING CHARGING}</li>
     *   <li>{@link #FLASH_STATE_READY READY}</li>
     *   <li>{@link #FLASH_STATE_FIRED FIRED}</li>
     *   <li>{@link #FLASH_STATE_PARTIAL PARTIAL}</li>
     * </ul></p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Limited capability</b> -
     * Present on all camera devices that report being at least {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED HARDWARE_LEVEL_LIMITED} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CameraCharacteristics#FLASH_INFO_AVAILABLE
     * @see CaptureRequest#FLASH_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see #FLASH_STATE_UNAVAILABLE
     * @see #FLASH_STATE_CHARGING
     * @see #FLASH_STATE_READY
     * @see #FLASH_STATE_FIRED
     * @see #FLASH_STATE_PARTIAL
     */
    @PublicKey
    public static final Key<Integer> FLASH_STATE =
            new Key<Integer>("android.flash.state", int.class);

    /**
     * <p>Operational mode for hot pixel correction.</p>
     * <p>Hotpixel correction interpolates out, or otherwise removes, pixels
     * that do not accurately measure the incoming light (i.e. pixels that
     * are stuck at an arbitrary value or are oversensitive).</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #HOT_PIXEL_MODE_OFF OFF}</li>
     *   <li>{@link #HOT_PIXEL_MODE_FAST FAST}</li>
     *   <li>{@link #HOT_PIXEL_MODE_HIGH_QUALITY HIGH_QUALITY}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#HOT_PIXEL_AVAILABLE_HOT_PIXEL_MODES android.hotPixel.availableHotPixelModes}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CameraCharacteristics#HOT_PIXEL_AVAILABLE_HOT_PIXEL_MODES
     * @see #HOT_PIXEL_MODE_OFF
     * @see #HOT_PIXEL_MODE_FAST
     * @see #HOT_PIXEL_MODE_HIGH_QUALITY
     */
    @PublicKey
    public static final Key<Integer> HOT_PIXEL_MODE =
            new Key<Integer>("android.hotPixel.mode", int.class);

    /**
     * <p>A location object to use when generating image GPS metadata.</p>
     * <p>Setting a location object in a request will include the GPS coordinates of the location
     * into any JPEG images captured based on the request. These coordinates can then be
     * viewed by anyone who receives the JPEG image.</p>
     * <p>This key is available on all devices.</p>
     */
    @PublicKey
    @SyntheticKey
    public static final Key<android.location.Location> JPEG_GPS_LOCATION =
            new Key<android.location.Location>("android.jpeg.gpsLocation", android.location.Location.class);

    /**
     * <p>GPS coordinates to include in output JPEG
     * EXIF.</p>
     * <p><b>Range of valid values:</b><br>
     * (-180 - 180], [-90,90], [-inf, inf]</p>
     * <p>This key is available on all devices.</p>
     * @hide
     */
    public static final Key<double[]> JPEG_GPS_COORDINATES =
            new Key<double[]>("android.jpeg.gpsCoordinates", double[].class);

    /**
     * <p>32 characters describing GPS algorithm to
     * include in EXIF.</p>
     * <p><b>Units</b>: UTF-8 null-terminated string</p>
     * <p>This key is available on all devices.</p>
     * @hide
     */
    public static final Key<String> JPEG_GPS_PROCESSING_METHOD =
            new Key<String>("android.jpeg.gpsProcessingMethod", String.class);

    /**
     * <p>Time GPS fix was made to include in
     * EXIF.</p>
     * <p><b>Units</b>: UTC in seconds since January 1, 1970</p>
     * <p>This key is available on all devices.</p>
     * @hide
     */
    public static final Key<Long> JPEG_GPS_TIMESTAMP =
            new Key<Long>("android.jpeg.gpsTimestamp", long.class);

    /**
     * <p>The orientation for a JPEG image.</p>
     * <p>The clockwise rotation angle in degrees, relative to the orientation
     * to the camera, that the JPEG picture needs to be rotated by, to be viewed
     * upright.</p>
     * <p>Camera devices may either encode this value into the JPEG EXIF header, or
     * rotate the image data to match this orientation. When the image data is rotated,
     * the thumbnail data will also be rotated.</p>
     * <p>Note that this orientation is relative to the orientation of the camera sensor, given
     * by {@link CameraCharacteristics#SENSOR_ORIENTATION android.sensor.orientation}.</p>
     * <p>To translate from the device orientation given by the Android sensor APIs, the following
     * sample code may be used:</p>
     * <pre><code>private int getJpegOrientation(CameraCharacteristics c, int deviceOrientation) {
     *     if (deviceOrientation == android.view.OrientationEventListener.ORIENTATION_UNKNOWN) return 0;
     *     int sensorOrientation = c.get(CameraCharacteristics.SENSOR_ORIENTATION);
     *
     *     // Round device orientation to a multiple of 90
     *     deviceOrientation = (deviceOrientation + 45) / 90 * 90;
     *
     *     // Reverse device orientation for front-facing cameras
     *     boolean facingFront = c.get(CameraCharacteristics.LENS_FACING) == CameraCharacteristics.LENS_FACING_FRONT;
     *     if (facingFront) deviceOrientation = -deviceOrientation;
     *
     *     // Calculate desired JPEG orientation relative to camera orientation to make
     *     // the image upright relative to the device orientation
     *     int jpegOrientation = (sensorOrientation + deviceOrientation + 360) % 360;
     *
     *     return jpegOrientation;
     * }
     * </code></pre>
     * <p><b>Units</b>: Degrees in multiples of 90</p>
     * <p><b>Range of valid values:</b><br>
     * 0, 90, 180, 270</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#SENSOR_ORIENTATION
     */
    @PublicKey
    public static final Key<Integer> JPEG_ORIENTATION =
            new Key<Integer>("android.jpeg.orientation", int.class);

    /**
     * <p>Compression quality of the final JPEG
     * image.</p>
     * <p>85-95 is typical usage range.</p>
     * <p><b>Range of valid values:</b><br>
     * 1-100; larger is higher quality</p>
     * <p>This key is available on all devices.</p>
     */
    @PublicKey
    public static final Key<Byte> JPEG_QUALITY =
            new Key<Byte>("android.jpeg.quality", byte.class);

    /**
     * <p>Compression quality of JPEG
     * thumbnail.</p>
     * <p><b>Range of valid values:</b><br>
     * 1-100; larger is higher quality</p>
     * <p>This key is available on all devices.</p>
     */
    @PublicKey
    public static final Key<Byte> JPEG_THUMBNAIL_QUALITY =
            new Key<Byte>("android.jpeg.thumbnailQuality", byte.class);

    /**
     * <p>Resolution of embedded JPEG thumbnail.</p>
     * <p>When set to (0, 0) value, the JPEG EXIF will not contain thumbnail,
     * but the captured JPEG will still be a valid image.</p>
     * <p>For best results, when issuing a request for a JPEG image, the thumbnail size selected
     * should have the same aspect ratio as the main JPEG output.</p>
     * <p>If the thumbnail image aspect ratio differs from the JPEG primary image aspect
     * ratio, the camera device creates the thumbnail by cropping it from the primary image.
     * For example, if the primary image has 4:3 aspect ratio, the thumbnail image has
     * 16:9 aspect ratio, the primary image will be cropped vertically (letterbox) to
     * generate the thumbnail image. The thumbnail image will always have a smaller Field
     * Of View (FOV) than the primary image when aspect ratios differ.</p>
     * <p>When an {@link CaptureRequest#JPEG_ORIENTATION android.jpeg.orientation} of non-zero degree is requested,
     * the camera device will handle thumbnail rotation in one of the following ways:</p>
     * <ul>
     * <li>Set the {@link android.media.ExifInterface#TAG_ORIENTATION EXIF orientation flag}
     *   and keep jpeg and thumbnail image data unrotated.</li>
     * <li>Rotate the jpeg and thumbnail image data and not set
     *   {@link android.media.ExifInterface#TAG_ORIENTATION EXIF orientation flag}. In this
     *   case, LIMITED or FULL hardware level devices will report rotated thumnail size in
     *   capture result, so the width and height will be interchanged if 90 or 270 degree
     *   orientation is requested. LEGACY device will always report unrotated thumbnail
     *   size.</li>
     * </ul>
     * <p><b>Range of valid values:</b><br>
     * {@link CameraCharacteristics#JPEG_AVAILABLE_THUMBNAIL_SIZES android.jpeg.availableThumbnailSizes}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#JPEG_AVAILABLE_THUMBNAIL_SIZES
     * @see CaptureRequest#JPEG_ORIENTATION
     */
    @PublicKey
    public static final Key<android.util.Size> JPEG_THUMBNAIL_SIZE =
            new Key<android.util.Size>("android.jpeg.thumbnailSize", android.util.Size.class);

    /**
     * <p>The desired lens aperture size, as a ratio of lens focal length to the
     * effective aperture diameter.</p>
     * <p>Setting this value is only supported on the camera devices that have a variable
     * aperture lens.</p>
     * <p>When this is supported and {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} is OFF,
     * this can be set along with {@link CaptureRequest#SENSOR_EXPOSURE_TIME android.sensor.exposureTime},
     * {@link CaptureRequest#SENSOR_SENSITIVITY android.sensor.sensitivity}, and {@link CaptureRequest#SENSOR_FRAME_DURATION android.sensor.frameDuration}
     * to achieve manual exposure control.</p>
     * <p>The requested aperture value may take several frames to reach the
     * requested value; the camera device will report the current (intermediate)
     * aperture size in capture result metadata while the aperture is changing.
     * While the aperture is still changing, {@link CaptureResult#LENS_STATE android.lens.state} will be set to MOVING.</p>
     * <p>When this is supported and {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} is one of
     * the ON modes, this will be overridden by the camera device
     * auto-exposure algorithm, the overridden values are then provided
     * back to the user in the corresponding result.</p>
     * <p><b>Units</b>: The f-number (f/N)</p>
     * <p><b>Range of valid values:</b><br>
     * {@link CameraCharacteristics#LENS_INFO_AVAILABLE_APERTURES android.lens.info.availableApertures}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#LENS_INFO_AVAILABLE_APERTURES
     * @see CaptureResult#LENS_STATE
     * @see CaptureRequest#SENSOR_EXPOSURE_TIME
     * @see CaptureRequest#SENSOR_FRAME_DURATION
     * @see CaptureRequest#SENSOR_SENSITIVITY
     */
    @PublicKey
    public static final Key<Float> LENS_APERTURE =
            new Key<Float>("android.lens.aperture", float.class);

    /**
     * <p>The desired setting for the lens neutral density filter(s).</p>
     * <p>This control will not be supported on most camera devices.</p>
     * <p>Lens filters are typically used to lower the amount of light the
     * sensor is exposed to (measured in steps of EV). As used here, an EV
     * step is the standard logarithmic representation, which are
     * non-negative, and inversely proportional to the amount of light
     * hitting the sensor.  For example, setting this to 0 would result
     * in no reduction of the incoming light, and setting this to 2 would
     * mean that the filter is set to reduce incoming light by two stops
     * (allowing 1/4 of the prior amount of light to the sensor).</p>
     * <p>It may take several frames before the lens filter density changes
     * to the requested value. While the filter density is still changing,
     * {@link CaptureResult#LENS_STATE android.lens.state} will be set to MOVING.</p>
     * <p><b>Units</b>: Exposure Value (EV)</p>
     * <p><b>Range of valid values:</b><br>
     * {@link CameraCharacteristics#LENS_INFO_AVAILABLE_FILTER_DENSITIES android.lens.info.availableFilterDensities}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#LENS_INFO_AVAILABLE_FILTER_DENSITIES
     * @see CaptureResult#LENS_STATE
     */
    @PublicKey
    public static final Key<Float> LENS_FILTER_DENSITY =
            new Key<Float>("android.lens.filterDensity", float.class);

    /**
     * <p>The desired lens focal length; used for optical zoom.</p>
     * <p>This setting controls the physical focal length of the camera
     * device's lens. Changing the focal length changes the field of
     * view of the camera device, and is usually used for optical zoom.</p>
     * <p>Like {@link CaptureRequest#LENS_FOCUS_DISTANCE android.lens.focusDistance} and {@link CaptureRequest#LENS_APERTURE android.lens.aperture}, this
     * setting won't be applied instantaneously, and it may take several
     * frames before the lens can change to the requested focal length.
     * While the focal length is still changing, {@link CaptureResult#LENS_STATE android.lens.state} will
     * be set to MOVING.</p>
     * <p>Optical zoom will not be supported on most devices.</p>
     * <p><b>Units</b>: Millimeters</p>
     * <p><b>Range of valid values:</b><br>
     * {@link CameraCharacteristics#LENS_INFO_AVAILABLE_FOCAL_LENGTHS android.lens.info.availableFocalLengths}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#LENS_APERTURE
     * @see CaptureRequest#LENS_FOCUS_DISTANCE
     * @see CameraCharacteristics#LENS_INFO_AVAILABLE_FOCAL_LENGTHS
     * @see CaptureResult#LENS_STATE
     */
    @PublicKey
    public static final Key<Float> LENS_FOCAL_LENGTH =
            new Key<Float>("android.lens.focalLength", float.class);

    /**
     * <p>Desired distance to plane of sharpest focus,
     * measured from frontmost surface of the lens.</p>
     * <p>Should be zero for fixed-focus cameras</p>
     * <p><b>Units</b>: See {@link CameraCharacteristics#LENS_INFO_FOCUS_DISTANCE_CALIBRATION android.lens.info.focusDistanceCalibration} for details</p>
     * <p><b>Range of valid values:</b><br>
     * &gt;= 0</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#LENS_INFO_FOCUS_DISTANCE_CALIBRATION
     */
    @PublicKey
    public static final Key<Float> LENS_FOCUS_DISTANCE =
            new Key<Float>("android.lens.focusDistance", float.class);

    /**
     * <p>The range of scene distances that are in
     * sharp focus (depth of field).</p>
     * <p>If variable focus not supported, can still report
     * fixed depth of field range</p>
     * <p><b>Units</b>: A pair of focus distances in diopters: (near,
     * far); see {@link CameraCharacteristics#LENS_INFO_FOCUS_DISTANCE_CALIBRATION android.lens.info.focusDistanceCalibration} for details.</p>
     * <p><b>Range of valid values:</b><br>
     * &gt;=0</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Limited capability</b> -
     * Present on all camera devices that report being at least {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED HARDWARE_LEVEL_LIMITED} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#LENS_INFO_FOCUS_DISTANCE_CALIBRATION
     */
    @PublicKey
    public static final Key<android.util.Pair<Float,Float>> LENS_FOCUS_RANGE =
            new Key<android.util.Pair<Float,Float>>("android.lens.focusRange", new TypeReference<android.util.Pair<Float,Float>>() {{ }});

    /**
     * <p>Sets whether the camera device uses optical image stabilization (OIS)
     * when capturing images.</p>
     * <p>OIS is used to compensate for motion blur due to small
     * movements of the camera during capture. Unlike digital image
     * stabilization ({@link CaptureRequest#CONTROL_VIDEO_STABILIZATION_MODE android.control.videoStabilizationMode}), OIS
     * makes use of mechanical elements to stabilize the camera
     * sensor, and thus allows for longer exposure times before
     * camera shake becomes apparent.</p>
     * <p>Switching between different optical stabilization modes may take several
     * frames to initialize, the camera device will report the current mode in
     * capture result metadata. For example, When "ON" mode is requested, the
     * optical stabilization modes in the first several capture results may still
     * be "OFF", and it will become "ON" when the initialization is done.</p>
     * <p>If a camera device supports both OIS and digital image stabilization
     * ({@link CaptureRequest#CONTROL_VIDEO_STABILIZATION_MODE android.control.videoStabilizationMode}), turning both modes on may produce undesirable
     * interaction, so it is recommended not to enable both at the same time.</p>
     * <p>Not all devices will support OIS; see
     * {@link CameraCharacteristics#LENS_INFO_AVAILABLE_OPTICAL_STABILIZATION android.lens.info.availableOpticalStabilization} for
     * available controls.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #LENS_OPTICAL_STABILIZATION_MODE_OFF OFF}</li>
     *   <li>{@link #LENS_OPTICAL_STABILIZATION_MODE_ON ON}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#LENS_INFO_AVAILABLE_OPTICAL_STABILIZATION android.lens.info.availableOpticalStabilization}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Limited capability</b> -
     * Present on all camera devices that report being at least {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED HARDWARE_LEVEL_LIMITED} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#CONTROL_VIDEO_STABILIZATION_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#LENS_INFO_AVAILABLE_OPTICAL_STABILIZATION
     * @see #LENS_OPTICAL_STABILIZATION_MODE_OFF
     * @see #LENS_OPTICAL_STABILIZATION_MODE_ON
     */
    @PublicKey
    public static final Key<Integer> LENS_OPTICAL_STABILIZATION_MODE =
            new Key<Integer>("android.lens.opticalStabilizationMode", int.class);

    /**
     * <p>Current lens status.</p>
     * <p>For lens parameters {@link CaptureRequest#LENS_FOCAL_LENGTH android.lens.focalLength}, {@link CaptureRequest#LENS_FOCUS_DISTANCE android.lens.focusDistance},
     * {@link CaptureRequest#LENS_FILTER_DENSITY android.lens.filterDensity} and {@link CaptureRequest#LENS_APERTURE android.lens.aperture}, when changes are requested,
     * they may take several frames to reach the requested values. This state indicates
     * the current status of the lens parameters.</p>
     * <p>When the state is STATIONARY, the lens parameters are not changing. This could be
     * either because the parameters are all fixed, or because the lens has had enough
     * time to reach the most recently-requested values.
     * If all these lens parameters are not changable for a camera device, as listed below:</p>
     * <ul>
     * <li>Fixed focus (<code>{@link CameraCharacteristics#LENS_INFO_MINIMUM_FOCUS_DISTANCE android.lens.info.minimumFocusDistance} == 0</code>), which means
     * {@link CaptureRequest#LENS_FOCUS_DISTANCE android.lens.focusDistance} parameter will always be 0.</li>
     * <li>Fixed focal length ({@link CameraCharacteristics#LENS_INFO_AVAILABLE_FOCAL_LENGTHS android.lens.info.availableFocalLengths} contains single value),
     * which means the optical zoom is not supported.</li>
     * <li>No ND filter ({@link CameraCharacteristics#LENS_INFO_AVAILABLE_FILTER_DENSITIES android.lens.info.availableFilterDensities} contains only 0).</li>
     * <li>Fixed aperture ({@link CameraCharacteristics#LENS_INFO_AVAILABLE_APERTURES android.lens.info.availableApertures} contains single value).</li>
     * </ul>
     * <p>Then this state will always be STATIONARY.</p>
     * <p>When the state is MOVING, it indicates that at least one of the lens parameters
     * is changing.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #LENS_STATE_STATIONARY STATIONARY}</li>
     *   <li>{@link #LENS_STATE_MOVING MOVING}</li>
     * </ul></p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Limited capability</b> -
     * Present on all camera devices that report being at least {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED HARDWARE_LEVEL_LIMITED} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CaptureRequest#LENS_APERTURE
     * @see CaptureRequest#LENS_FILTER_DENSITY
     * @see CaptureRequest#LENS_FOCAL_LENGTH
     * @see CaptureRequest#LENS_FOCUS_DISTANCE
     * @see CameraCharacteristics#LENS_INFO_AVAILABLE_APERTURES
     * @see CameraCharacteristics#LENS_INFO_AVAILABLE_FILTER_DENSITIES
     * @see CameraCharacteristics#LENS_INFO_AVAILABLE_FOCAL_LENGTHS
     * @see CameraCharacteristics#LENS_INFO_MINIMUM_FOCUS_DISTANCE
     * @see #LENS_STATE_STATIONARY
     * @see #LENS_STATE_MOVING
     */
    @PublicKey
    public static final Key<Integer> LENS_STATE =
            new Key<Integer>("android.lens.state", int.class);

    /**
     * <p>The orientation of the camera relative to the sensor
     * coordinate system.</p>
     * <p>The four coefficients that describe the quaternion
     * rotation from the Android sensor coordinate system to a
     * camera-aligned coordinate system where the X-axis is
     * aligned with the long side of the image sensor, the Y-axis
     * is aligned with the short side of the image sensor, and
     * the Z-axis is aligned with the optical axis of the sensor.</p>
     * <p>To convert from the quaternion coefficients <code>(x,y,z,w)</code>
     * to the axis of rotation <code>(a_x, a_y, a_z)</code> and rotation
     * amount <code>theta</code>, the following formulas can be used:</p>
     * <pre><code> theta = 2 * acos(w)
     * a_x = x / sin(theta/2)
     * a_y = y / sin(theta/2)
     * a_z = z / sin(theta/2)
     * </code></pre>
     * <p>To create a 3x3 rotation matrix that applies the rotation
     * defined by this quaternion, the following matrix can be
     * used:</p>
     * <pre><code>R = [ 1 - 2y^2 - 2z^2,       2xy - 2zw,       2xz + 2yw,
     *            2xy + 2zw, 1 - 2x^2 - 2z^2,       2yz - 2xw,
     *            2xz - 2yw,       2yz + 2xw, 1 - 2x^2 - 2y^2 ]
     * </code></pre>
     * <p>This matrix can then be used to apply the rotation to a
     *  column vector point with</p>
     * <p><code>p' = Rp</code></p>
     * <p>where <code>p</code> is in the device sensor coordinate system, and
     *  <code>p'</code> is in the camera-oriented coordinate system.</p>
     * <p><b>Units</b>:
     * Quaternion coefficients</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     */
    @PublicKey
    public static final Key<float[]> LENS_POSE_ROTATION =
            new Key<float[]>("android.lens.poseRotation", float[].class);

    /**
     * <p>Position of the camera optical center.</p>
     * <p>The position of the camera device's lens optical center,
     * as a three-dimensional vector <code>(x,y,z)</code>, relative to the
     * optical center of the largest camera device facing in the
     * same direction as this camera, in the {@link android.hardware.SensorEvent Android sensor coordinate
     * axes}. Note that only the axis definitions are shared with
     * the sensor coordinate system, but not the origin.</p>
     * <p>If this device is the largest or only camera device with a
     * given facing, then this position will be <code>(0, 0, 0)</code>; a
     * camera device with a lens optical center located 3 cm from
     * the main sensor along the +X axis (to the right from the
     * user's perspective) will report <code>(0.03, 0, 0)</code>.</p>
     * <p>To transform a pixel coordinates between two cameras
     * facing the same direction, first the source camera
     * {@link CameraCharacteristics#LENS_RADIAL_DISTORTION android.lens.radialDistortion} must be corrected for.  Then
     * the source camera {@link CameraCharacteristics#LENS_INTRINSIC_CALIBRATION android.lens.intrinsicCalibration} needs
     * to be applied, followed by the {@link CameraCharacteristics#LENS_POSE_ROTATION android.lens.poseRotation}
     * of the source camera, the translation of the source camera
     * relative to the destination camera, the
     * {@link CameraCharacteristics#LENS_POSE_ROTATION android.lens.poseRotation} of the destination camera, and
     * finally the inverse of {@link CameraCharacteristics#LENS_INTRINSIC_CALIBRATION android.lens.intrinsicCalibration}
     * of the destination camera. This obtains a
     * radial-distortion-free coordinate in the destination
     * camera pixel coordinates.</p>
     * <p>To compare this against a real image from the destination
     * camera, the destination camera image then needs to be
     * corrected for radial distortion before comparison or
     * sampling.</p>
     * <p><b>Units</b>: Meters</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CameraCharacteristics#LENS_INTRINSIC_CALIBRATION
     * @see CameraCharacteristics#LENS_POSE_ROTATION
     * @see CameraCharacteristics#LENS_RADIAL_DISTORTION
     */
    @PublicKey
    public static final Key<float[]> LENS_POSE_TRANSLATION =
            new Key<float[]>("android.lens.poseTranslation", float[].class);

    /**
     * <p>The parameters for this camera device's intrinsic
     * calibration.</p>
     * <p>The five calibration parameters that describe the
     * transform from camera-centric 3D coordinates to sensor
     * pixel coordinates:</p>
     * <pre><code>[f_x, f_y, c_x, c_y, s]
     * </code></pre>
     * <p>Where <code>f_x</code> and <code>f_y</code> are the horizontal and vertical
     * focal lengths, <code>[c_x, c_y]</code> is the position of the optical
     * axis, and <code>s</code> is a skew parameter for the sensor plane not
     * being aligned with the lens plane.</p>
     * <p>These are typically used within a transformation matrix K:</p>
     * <pre><code>K = [ f_x,   s, c_x,
     *        0, f_y, c_y,
     *        0    0,   1 ]
     * </code></pre>
     * <p>which can then be combined with the camera pose rotation
     * <code>R</code> and translation <code>t</code> ({@link CameraCharacteristics#LENS_POSE_ROTATION android.lens.poseRotation} and
     * {@link CameraCharacteristics#LENS_POSE_TRANSLATION android.lens.poseTranslation}, respective) to calculate the
     * complete transform from world coordinates to pixel
     * coordinates:</p>
     * <pre><code>P = [ K 0   * [ R t
     *      0 1 ]     0 1 ]
     * </code></pre>
     * <p>and with <code>p_w</code> being a point in the world coordinate system
     * and <code>p_s</code> being a point in the camera active pixel array
     * coordinate system, and with the mapping including the
     * homogeneous division by z:</p>
     * <pre><code> p_h = (x_h, y_h, z_h) = P p_w
     * p_s = p_h / z_h
     * </code></pre>
     * <p>so <code>[x_s, y_s]</code> is the pixel coordinates of the world
     * point, <code>z_s = 1</code>, and <code>w_s</code> is a measurement of disparity
     * (depth) in pixel coordinates.</p>
     * <p>Note that the coordinate system for this transform is the
     * {@link CameraCharacteristics#SENSOR_INFO_PRE_CORRECTION_ACTIVE_ARRAY_SIZE android.sensor.info.preCorrectionActiveArraySize} system,
     * where <code>(0,0)</code> is the top-left of the
     * preCorrectionActiveArraySize rectangle. Once the pose and
     * intrinsic calibration transforms have been applied to a
     * world point, then the {@link CameraCharacteristics#LENS_RADIAL_DISTORTION android.lens.radialDistortion}
     * transform needs to be applied, and the result adjusted to
     * be in the {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize} coordinate
     * system (where <code>(0, 0)</code> is the top-left of the
     * activeArraySize rectangle), to determine the final pixel
     * coordinate of the world point for processed (non-RAW)
     * output buffers.</p>
     * <p><b>Units</b>:
     * Pixels in the
     * {@link CameraCharacteristics#SENSOR_INFO_PRE_CORRECTION_ACTIVE_ARRAY_SIZE android.sensor.info.preCorrectionActiveArraySize}
     * coordinate system.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CameraCharacteristics#LENS_POSE_ROTATION
     * @see CameraCharacteristics#LENS_POSE_TRANSLATION
     * @see CameraCharacteristics#LENS_RADIAL_DISTORTION
     * @see CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE
     * @see CameraCharacteristics#SENSOR_INFO_PRE_CORRECTION_ACTIVE_ARRAY_SIZE
     */
    @PublicKey
    public static final Key<float[]> LENS_INTRINSIC_CALIBRATION =
            new Key<float[]>("android.lens.intrinsicCalibration", float[].class);

    /**
     * <p>The correction coefficients to correct for this camera device's
     * radial and tangential lens distortion.</p>
     * <p>Four radial distortion coefficients <code>[kappa_0, kappa_1, kappa_2,
     * kappa_3]</code> and two tangential distortion coefficients
     * <code>[kappa_4, kappa_5]</code> that can be used to correct the
     * lens's geometric distortion with the mapping equations:</p>
     * <pre><code> x_c = x_i * ( kappa_0 + kappa_1 * r^2 + kappa_2 * r^4 + kappa_3 * r^6 ) +
     *        kappa_4 * (2 * x_i * y_i) + kappa_5 * ( r^2 + 2 * x_i^2 )
     *  y_c = y_i * ( kappa_0 + kappa_1 * r^2 + kappa_2 * r^4 + kappa_3 * r^6 ) +
     *        kappa_5 * (2 * x_i * y_i) + kappa_4 * ( r^2 + 2 * y_i^2 )
     * </code></pre>
     * <p>Here, <code>[x_c, y_c]</code> are the coordinates to sample in the
     * input image that correspond to the pixel values in the
     * corrected image at the coordinate <code>[x_i, y_i]</code>:</p>
     * <pre><code> correctedImage(x_i, y_i) = sample_at(x_c, y_c, inputImage)
     * </code></pre>
     * <p>The pixel coordinates are defined in a normalized
     * coordinate system related to the
     * {@link CameraCharacteristics#LENS_INTRINSIC_CALIBRATION android.lens.intrinsicCalibration} calibration fields.
     * Both <code>[x_i, y_i]</code> and <code>[x_c, y_c]</code> have <code>(0,0)</code> at the
     * lens optical center <code>[c_x, c_y]</code>. The maximum magnitudes
     * of both x and y coordinates are normalized to be 1 at the
     * edge further from the optical center, so the range
     * for both dimensions is <code>-1 &lt;= x &lt;= 1</code>.</p>
     * <p>Finally, <code>r</code> represents the radial distance from the
     * optical center, <code>r^2 = x_i^2 + y_i^2</code>, and its magnitude
     * is therefore no larger than <code>|r| &lt;= sqrt(2)</code>.</p>
     * <p>The distortion model used is the Brown-Conrady model.</p>
     * <p><b>Units</b>:
     * Unitless coefficients.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CameraCharacteristics#LENS_INTRINSIC_CALIBRATION
     */
    @PublicKey
    public static final Key<float[]> LENS_RADIAL_DISTORTION =
            new Key<float[]>("android.lens.radialDistortion", float[].class);

    /**
     * <p>Mode of operation for the noise reduction algorithm.</p>
     * <p>The noise reduction algorithm attempts to improve image quality by removing
     * excessive noise added by the capture process, especially in dark conditions.</p>
     * <p>OFF means no noise reduction will be applied by the camera device, for both raw and
     * YUV domain.</p>
     * <p>MINIMAL means that only sensor raw domain basic noise reduction is enabled ,to remove
     * demosaicing or other processing artifacts. For YUV_REPROCESSING, MINIMAL is same as OFF.
     * This mode is optional, may not be support by all devices. The application should check
     * {@link CameraCharacteristics#NOISE_REDUCTION_AVAILABLE_NOISE_REDUCTION_MODES android.noiseReduction.availableNoiseReductionModes} before using it.</p>
     * <p>FAST/HIGH_QUALITY both mean camera device determined noise filtering
     * will be applied. HIGH_QUALITY mode indicates that the camera device
     * will use the highest-quality noise filtering algorithms,
     * even if it slows down capture rate. FAST means the camera device will not
     * slow down capture rate when applying noise filtering. FAST may be the same as MINIMAL if
     * MINIMAL is listed, or the same as OFF if any noise filtering will slow down capture rate.
     * Every output stream will have a similar amount of enhancement applied.</p>
     * <p>ZERO_SHUTTER_LAG is meant to be used by applications that maintain a continuous circular
     * buffer of high-resolution images during preview and reprocess image(s) from that buffer
     * into a final capture when triggered by the user. In this mode, the camera device applies
     * noise reduction to low-resolution streams (below maximum recording resolution) to maximize
     * preview quality, but does not apply noise reduction to high-resolution streams, since
     * those will be reprocessed later if necessary.</p>
     * <p>For YUV_REPROCESSING, these FAST/HIGH_QUALITY modes both mean that the camera device
     * will apply FAST/HIGH_QUALITY YUV domain noise reduction, respectively. The camera device
     * may adjust the noise reduction parameters for best image quality based on the
     * {@link CaptureRequest#REPROCESS_EFFECTIVE_EXPOSURE_FACTOR android.reprocess.effectiveExposureFactor} if it is set.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #NOISE_REDUCTION_MODE_OFF OFF}</li>
     *   <li>{@link #NOISE_REDUCTION_MODE_FAST FAST}</li>
     *   <li>{@link #NOISE_REDUCTION_MODE_HIGH_QUALITY HIGH_QUALITY}</li>
     *   <li>{@link #NOISE_REDUCTION_MODE_MINIMAL MINIMAL}</li>
     *   <li>{@link #NOISE_REDUCTION_MODE_ZERO_SHUTTER_LAG ZERO_SHUTTER_LAG}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#NOISE_REDUCTION_AVAILABLE_NOISE_REDUCTION_MODES android.noiseReduction.availableNoiseReductionModes}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#NOISE_REDUCTION_AVAILABLE_NOISE_REDUCTION_MODES
     * @see CaptureRequest#REPROCESS_EFFECTIVE_EXPOSURE_FACTOR
     * @see #NOISE_REDUCTION_MODE_OFF
     * @see #NOISE_REDUCTION_MODE_FAST
     * @see #NOISE_REDUCTION_MODE_HIGH_QUALITY
     * @see #NOISE_REDUCTION_MODE_MINIMAL
     * @see #NOISE_REDUCTION_MODE_ZERO_SHUTTER_LAG
     */
    @PublicKey
    public static final Key<Integer> NOISE_REDUCTION_MODE =
            new Key<Integer>("android.noiseReduction.mode", int.class);

    /**
     * <p>Whether a result given to the framework is the
     * final one for the capture, or only a partial that contains a
     * subset of the full set of dynamic metadata
     * values.</p>
     * <p>The entries in the result metadata buffers for a
     * single capture may not overlap, except for this entry. The
     * FINAL buffers must retain FIFO ordering relative to the
     * requests that generate them, so the FINAL buffer for frame 3 must
     * always be sent to the framework after the FINAL buffer for frame 2, and
     * before the FINAL buffer for frame 4. PARTIAL buffers may be returned
     * in any order relative to other frames, but all PARTIAL buffers for a given
     * capture must arrive before the FINAL buffer for that capture. This entry may
     * only be used by the camera device if quirks.usePartialResult is set to 1.</p>
     * <p><b>Range of valid values:</b><br>
     * Optional. Default value is FINAL.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * @deprecated
     * @hide
     */
    @Deprecated
    public static final Key<Boolean> QUIRKS_PARTIAL_RESULT =
            new Key<Boolean>("android.quirks.partialResult", boolean.class);

    /**
     * <p>A frame counter set by the framework. This value monotonically
     * increases with every new result (that is, each new result has a unique
     * frameCount value).</p>
     * <p>Reset on release()</p>
     * <p><b>Units</b>: count of frames</p>
     * <p><b>Range of valid values:</b><br>
     * &gt; 0</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * @deprecated
     * @hide
     */
    @Deprecated
    public static final Key<Integer> REQUEST_FRAME_COUNT =
            new Key<Integer>("android.request.frameCount", int.class);

    /**
     * <p>An application-specified ID for the current
     * request. Must be maintained unchanged in output
     * frame</p>
     * <p><b>Units</b>: arbitrary integer assigned by application</p>
     * <p><b>Range of valid values:</b><br>
     * Any int</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * @hide
     */
    public static final Key<Integer> REQUEST_ID =
            new Key<Integer>("android.request.id", int.class);

    /**
     * <p>Specifies the number of pipeline stages the frame went
     * through from when it was exposed to when the final completed result
     * was available to the framework.</p>
     * <p>Depending on what settings are used in the request, and
     * what streams are configured, the data may undergo less processing,
     * and some pipeline stages skipped.</p>
     * <p>See {@link CameraCharacteristics#REQUEST_PIPELINE_MAX_DEPTH android.request.pipelineMaxDepth} for more details.</p>
     * <p><b>Range of valid values:</b><br>
     * &lt;= {@link CameraCharacteristics#REQUEST_PIPELINE_MAX_DEPTH android.request.pipelineMaxDepth}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#REQUEST_PIPELINE_MAX_DEPTH
     */
    @PublicKey
    public static final Key<Byte> REQUEST_PIPELINE_DEPTH =
            new Key<Byte>("android.request.pipelineDepth", byte.class);

    /**
     * <p>The desired region of the sensor to read out for this capture.</p>
     * <p>This control can be used to implement digital zoom.</p>
     * <p>The crop region coordinate system is based off
     * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}, with <code>(0, 0)</code> being the
     * top-left corner of the sensor active array.</p>
     * <p>Output streams use this rectangle to produce their output,
     * cropping to a smaller region if necessary to maintain the
     * stream's aspect ratio, then scaling the sensor input to
     * match the output's configured resolution.</p>
     * <p>The crop region is applied after the RAW to other color
     * space (e.g. YUV) conversion. Since raw streams
     * (e.g. RAW16) don't have the conversion stage, they are not
     * croppable. The crop region will be ignored by raw streams.</p>
     * <p>For non-raw streams, any additional per-stream cropping will
     * be done to maximize the final pixel area of the stream.</p>
     * <p>For example, if the crop region is set to a 4:3 aspect
     * ratio, then 4:3 streams will use the exact crop
     * region. 16:9 streams will further crop vertically
     * (letterbox).</p>
     * <p>Conversely, if the crop region is set to a 16:9, then 4:3
     * outputs will crop horizontally (pillarbox), and 16:9
     * streams will match exactly. These additional crops will
     * be centered within the crop region.</p>
     * <p>The width and height of the crop region cannot
     * be set to be smaller than
     * <code>floor( activeArraySize.width / {@link CameraCharacteristics#SCALER_AVAILABLE_MAX_DIGITAL_ZOOM android.scaler.availableMaxDigitalZoom} )</code> and
     * <code>floor( activeArraySize.height / {@link CameraCharacteristics#SCALER_AVAILABLE_MAX_DIGITAL_ZOOM android.scaler.availableMaxDigitalZoom} )</code>, respectively.</p>
     * <p>The camera device may adjust the crop region to account
     * for rounding and other hardware requirements; the final
     * crop region used will be included in the output capture
     * result.</p>
     * <p><b>Units</b>: Pixel coordinates relative to
     * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#SCALER_AVAILABLE_MAX_DIGITAL_ZOOM
     * @see CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE
     */
    @PublicKey
    public static final Key<android.graphics.Rect> SCALER_CROP_REGION =
            new Key<android.graphics.Rect>("android.scaler.cropRegion", android.graphics.Rect.class);

    /**
     * <p>Duration each pixel is exposed to
     * light.</p>
     * <p>If the sensor can't expose this exact duration, it will shorten the
     * duration exposed to the nearest possible value (rather than expose longer).
     * The final exposure time used will be available in the output capture result.</p>
     * <p>This control is only effective if {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} or {@link CaptureRequest#CONTROL_MODE android.control.mode} is set to
     * OFF; otherwise the auto-exposure algorithm will override this value.</p>
     * <p><b>Units</b>: Nanoseconds</p>
     * <p><b>Range of valid values:</b><br>
     * {@link CameraCharacteristics#SENSOR_INFO_EXPOSURE_TIME_RANGE android.sensor.info.exposureTimeRange}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CaptureRequest#CONTROL_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#SENSOR_INFO_EXPOSURE_TIME_RANGE
     */
    @PublicKey
    public static final Key<Long> SENSOR_EXPOSURE_TIME =
            new Key<Long>("android.sensor.exposureTime", long.class);

    /**
     * <p>Duration from start of frame exposure to
     * start of next frame exposure.</p>
     * <p>The maximum frame rate that can be supported by a camera subsystem is
     * a function of many factors:</p>
     * <ul>
     * <li>Requested resolutions of output image streams</li>
     * <li>Availability of binning / skipping modes on the imager</li>
     * <li>The bandwidth of the imager interface</li>
     * <li>The bandwidth of the various ISP processing blocks</li>
     * </ul>
     * <p>Since these factors can vary greatly between different ISPs and
     * sensors, the camera abstraction tries to represent the bandwidth
     * restrictions with as simple a model as possible.</p>
     * <p>The model presented has the following characteristics:</p>
     * <ul>
     * <li>The image sensor is always configured to output the smallest
     * resolution possible given the application's requested output stream
     * sizes.  The smallest resolution is defined as being at least as large
     * as the largest requested output stream size; the camera pipeline must
     * never digitally upsample sensor data when the crop region covers the
     * whole sensor. In general, this means that if only small output stream
     * resolutions are configured, the sensor can provide a higher frame
     * rate.</li>
     * <li>Since any request may use any or all the currently configured
     * output streams, the sensor and ISP must be configured to support
     * scaling a single capture to all the streams at the same time.  This
     * means the camera pipeline must be ready to produce the largest
     * requested output size without any delay.  Therefore, the overall
     * frame rate of a given configured stream set is governed only by the
     * largest requested stream resolution.</li>
     * <li>Using more than one output stream in a request does not affect the
     * frame duration.</li>
     * <li>Certain format-streams may need to do additional background processing
     * before data is consumed/produced by that stream. These processors
     * can run concurrently to the rest of the camera pipeline, but
     * cannot process more than 1 capture at a time.</li>
     * </ul>
     * <p>The necessary information for the application, given the model above,
     * is provided via the {@link CameraCharacteristics#SCALER_STREAM_CONFIGURATION_MAP android.scaler.streamConfigurationMap} field using
     * {@link android.hardware.camera2.params.StreamConfigurationMap#getOutputMinFrameDuration }.
     * These are used to determine the maximum frame rate / minimum frame
     * duration that is possible for a given stream configuration.</p>
     * <p>Specifically, the application can use the following rules to
     * determine the minimum frame duration it can request from the camera
     * device:</p>
     * <ol>
     * <li>Let the set of currently configured input/output streams
     * be called <code>S</code>.</li>
     * <li>Find the minimum frame durations for each stream in <code>S</code>, by looking
     * it up in {@link CameraCharacteristics#SCALER_STREAM_CONFIGURATION_MAP android.scaler.streamConfigurationMap} using {@link android.hardware.camera2.params.StreamConfigurationMap#getOutputMinFrameDuration }
     * (with its respective size/format). Let this set of frame durations be
     * called <code>F</code>.</li>
     * <li>For any given request <code>R</code>, the minimum frame duration allowed
     * for <code>R</code> is the maximum out of all values in <code>F</code>. Let the streams
     * used in <code>R</code> be called <code>S_r</code>.</li>
     * </ol>
     * <p>If none of the streams in <code>S_r</code> have a stall time (listed in {@link android.hardware.camera2.params.StreamConfigurationMap#getOutputStallDuration }
     * using its respective size/format), then the frame duration in <code>F</code>
     * determines the steady state frame rate that the application will get
     * if it uses <code>R</code> as a repeating request. Let this special kind of
     * request be called <code>Rsimple</code>.</p>
     * <p>A repeating request <code>Rsimple</code> can be <em>occasionally</em> interleaved
     * by a single capture of a new request <code>Rstall</code> (which has at least
     * one in-use stream with a non-0 stall time) and if <code>Rstall</code> has the
     * same minimum frame duration this will not cause a frame rate loss
     * if all buffers from the previous <code>Rstall</code> have already been
     * delivered.</p>
     * <p>For more details about stalling, see
     * {@link android.hardware.camera2.params.StreamConfigurationMap#getOutputStallDuration }.</p>
     * <p>This control is only effective if {@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} or {@link CaptureRequest#CONTROL_MODE android.control.mode} is set to
     * OFF; otherwise the auto-exposure algorithm will override this value.</p>
     * <p><b>Units</b>: Nanoseconds</p>
     * <p><b>Range of valid values:</b><br>
     * See {@link CameraCharacteristics#SENSOR_INFO_MAX_FRAME_DURATION android.sensor.info.maxFrameDuration},
     * {@link CameraCharacteristics#SCALER_STREAM_CONFIGURATION_MAP android.scaler.streamConfigurationMap}. The duration
     * is capped to <code>max(duration, exposureTime + overhead)</code>.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CaptureRequest#CONTROL_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#SCALER_STREAM_CONFIGURATION_MAP
     * @see CameraCharacteristics#SENSOR_INFO_MAX_FRAME_DURATION
     */
    @PublicKey
    public static final Key<Long> SENSOR_FRAME_DURATION =
            new Key<Long>("android.sensor.frameDuration", long.class);

    /**
     * <p>The amount of gain applied to sensor data
     * before processing.</p>
     * <p>The sensitivity is the standard ISO sensitivity value,
     * as defined in ISO 12232:2006.</p>
     * <p>The sensitivity must be within {@link CameraCharacteristics#SENSOR_INFO_SENSITIVITY_RANGE android.sensor.info.sensitivityRange}, and
     * if if it less than {@link CameraCharacteristics#SENSOR_MAX_ANALOG_SENSITIVITY android.sensor.maxAnalogSensitivity}, the camera device
     * is guaranteed to use only analog amplification for applying the gain.</p>
     * <p>If the camera device cannot apply the exact sensitivity
     * requested, it will reduce the gain to the nearest supported
     * value. The final sensitivity used will be available in the
     * output capture result.</p>
     * <p><b>Units</b>: ISO arithmetic units</p>
     * <p><b>Range of valid values:</b><br>
     * {@link CameraCharacteristics#SENSOR_INFO_SENSITIVITY_RANGE android.sensor.info.sensitivityRange}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#SENSOR_INFO_SENSITIVITY_RANGE
     * @see CameraCharacteristics#SENSOR_MAX_ANALOG_SENSITIVITY
     */
    @PublicKey
    public static final Key<Integer> SENSOR_SENSITIVITY =
            new Key<Integer>("android.sensor.sensitivity", int.class);

    /**
     * <p>Time at start of exposure of first
     * row of the image sensor active array, in nanoseconds.</p>
     * <p>The timestamps are also included in all image
     * buffers produced for the same capture, and will be identical
     * on all the outputs.</p>
     * <p>When {@link CameraCharacteristics#SENSOR_INFO_TIMESTAMP_SOURCE android.sensor.info.timestampSource} <code>==</code> UNKNOWN,
     * the timestamps measure time since an unspecified starting point,
     * and are monotonically increasing. They can be compared with the
     * timestamps for other captures from the same camera device, but are
     * not guaranteed to be comparable to any other time source.</p>
     * <p>When {@link CameraCharacteristics#SENSOR_INFO_TIMESTAMP_SOURCE android.sensor.info.timestampSource} <code>==</code> REALTIME, the
     * timestamps measure time in the same timebase as {@link android.os.SystemClock#elapsedRealtimeNanos }, and they can
     * be compared to other timestamps from other subsystems that
     * are using that base.</p>
     * <p>For reprocessing, the timestamp will match the start of exposure of
     * the input image, i.e. {@link CaptureResult#SENSOR_TIMESTAMP the
     * timestamp} in the TotalCaptureResult that was used to create the
     * reprocess capture request.</p>
     * <p><b>Units</b>: Nanoseconds</p>
     * <p><b>Range of valid values:</b><br>
     * &gt; 0</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#SENSOR_INFO_TIMESTAMP_SOURCE
     */
    @PublicKey
    public static final Key<Long> SENSOR_TIMESTAMP =
            new Key<Long>("android.sensor.timestamp", long.class);

    /**
     * <p>The estimated camera neutral color in the native sensor colorspace at
     * the time of capture.</p>
     * <p>This value gives the neutral color point encoded as an RGB value in the
     * native sensor color space.  The neutral color point indicates the
     * currently estimated white point of the scene illumination.  It can be
     * used to interpolate between the provided color transforms when
     * processing raw sensor data.</p>
     * <p>The order of the values is R, G, B; where R is in the lowest index.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     */
    @PublicKey
    public static final Key<Rational[]> SENSOR_NEUTRAL_COLOR_POINT =
            new Key<Rational[]>("android.sensor.neutralColorPoint", Rational[].class);

    /**
     * <p>Noise model coefficients for each CFA mosaic channel.</p>
     * <p>This key contains two noise model coefficients for each CFA channel
     * corresponding to the sensor amplification (S) and sensor readout
     * noise (O).  These are given as pairs of coefficients for each channel
     * in the same order as channels listed for the CFA layout key
     * (see {@link CameraCharacteristics#SENSOR_INFO_COLOR_FILTER_ARRANGEMENT android.sensor.info.colorFilterArrangement}).  This is
     * represented as an array of Pair&lt;Double, Double&gt;, where
     * the first member of the Pair at index n is the S coefficient and the
     * second member is the O coefficient for the nth color channel in the CFA.</p>
     * <p>These coefficients are used in a two parameter noise model to describe
     * the amount of noise present in the image for each CFA channel.  The
     * noise model used here is:</p>
     * <p>N(x) = sqrt(Sx + O)</p>
     * <p>Where x represents the recorded signal of a CFA channel normalized to
     * the range [0, 1], and S and O are the noise model coeffiecients for
     * that channel.</p>
     * <p>A more detailed description of the noise model can be found in the
     * Adobe DNG specification for the NoiseProfile tag.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CameraCharacteristics#SENSOR_INFO_COLOR_FILTER_ARRANGEMENT
     */
    @PublicKey
    public static final Key<android.util.Pair<Double,Double>[]> SENSOR_NOISE_PROFILE =
            new Key<android.util.Pair<Double,Double>[]>("android.sensor.noiseProfile", new TypeReference<android.util.Pair<Double,Double>[]>() {{ }});

    /**
     * <p>The worst-case divergence between Bayer green channels.</p>
     * <p>This value is an estimate of the worst case split between the
     * Bayer green channels in the red and blue rows in the sensor color
     * filter array.</p>
     * <p>The green split is calculated as follows:</p>
     * <ol>
     * <li>A 5x5 pixel (or larger) window W within the active sensor array is
     * chosen. The term 'pixel' here is taken to mean a group of 4 Bayer
     * mosaic channels (R, Gr, Gb, B).  The location and size of the window
     * chosen is implementation defined, and should be chosen to provide a
     * green split estimate that is both representative of the entire image
     * for this camera sensor, and can be calculated quickly.</li>
     * <li>The arithmetic mean of the green channels from the red
     * rows (mean_Gr) within W is computed.</li>
     * <li>The arithmetic mean of the green channels from the blue
     * rows (mean_Gb) within W is computed.</li>
     * <li>The maximum ratio R of the two means is computed as follows:
     * <code>R = max((mean_Gr + 1)/(mean_Gb + 1), (mean_Gb + 1)/(mean_Gr + 1))</code></li>
     * </ol>
     * <p>The ratio R is the green split divergence reported for this property,
     * which represents how much the green channels differ in the mosaic
     * pattern.  This value is typically used to determine the treatment of
     * the green mosaic channels when demosaicing.</p>
     * <p>The green split value can be roughly interpreted as follows:</p>
     * <ul>
     * <li>R &lt; 1.03 is a negligible split (&lt;3% divergence).</li>
     * <li>1.20 &lt;= R &gt;= 1.03 will require some software
     * correction to avoid demosaic errors (3-20% divergence).</li>
     * <li>R &gt; 1.20 will require strong software correction to produce
     * a usuable image (&gt;20% divergence).</li>
     * </ul>
     * <p><b>Range of valid values:</b><br></p>
     * <p>&gt;= 0</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     */
    @PublicKey
    public static final Key<Float> SENSOR_GREEN_SPLIT =
            new Key<Float>("android.sensor.greenSplit", float.class);

    /**
     * <p>A pixel <code>[R, G_even, G_odd, B]</code> that supplies the test pattern
     * when {@link CaptureRequest#SENSOR_TEST_PATTERN_MODE android.sensor.testPatternMode} is SOLID_COLOR.</p>
     * <p>Each color channel is treated as an unsigned 32-bit integer.
     * The camera device then uses the most significant X bits
     * that correspond to how many bits are in its Bayer raw sensor
     * output.</p>
     * <p>For example, a sensor with RAW10 Bayer output would use the
     * 10 most significant bits from each color channel.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CaptureRequest#SENSOR_TEST_PATTERN_MODE
     */
    @PublicKey
    public static final Key<int[]> SENSOR_TEST_PATTERN_DATA =
            new Key<int[]>("android.sensor.testPatternData", int[].class);

    /**
     * <p>When enabled, the sensor sends a test pattern instead of
     * doing a real exposure from the camera.</p>
     * <p>When a test pattern is enabled, all manual sensor controls specified
     * by android.sensor.* will be ignored. All other controls should
     * work as normal.</p>
     * <p>For example, if manual flash is enabled, flash firing should still
     * occur (and that the test pattern remain unmodified, since the flash
     * would not actually affect it).</p>
     * <p>Defaults to OFF.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #SENSOR_TEST_PATTERN_MODE_OFF OFF}</li>
     *   <li>{@link #SENSOR_TEST_PATTERN_MODE_SOLID_COLOR SOLID_COLOR}</li>
     *   <li>{@link #SENSOR_TEST_PATTERN_MODE_COLOR_BARS COLOR_BARS}</li>
     *   <li>{@link #SENSOR_TEST_PATTERN_MODE_COLOR_BARS_FADE_TO_GRAY COLOR_BARS_FADE_TO_GRAY}</li>
     *   <li>{@link #SENSOR_TEST_PATTERN_MODE_PN9 PN9}</li>
     *   <li>{@link #SENSOR_TEST_PATTERN_MODE_CUSTOM1 CUSTOM1}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#SENSOR_AVAILABLE_TEST_PATTERN_MODES android.sensor.availableTestPatternModes}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CameraCharacteristics#SENSOR_AVAILABLE_TEST_PATTERN_MODES
     * @see #SENSOR_TEST_PATTERN_MODE_OFF
     * @see #SENSOR_TEST_PATTERN_MODE_SOLID_COLOR
     * @see #SENSOR_TEST_PATTERN_MODE_COLOR_BARS
     * @see #SENSOR_TEST_PATTERN_MODE_COLOR_BARS_FADE_TO_GRAY
     * @see #SENSOR_TEST_PATTERN_MODE_PN9
     * @see #SENSOR_TEST_PATTERN_MODE_CUSTOM1
     */
    @PublicKey
    public static final Key<Integer> SENSOR_TEST_PATTERN_MODE =
            new Key<Integer>("android.sensor.testPatternMode", int.class);

    /**
     * <p>Duration between the start of first row exposure
     * and the start of last row exposure.</p>
     * <p>This is the exposure time skew between the first and last
     * row exposure start times. The first row and the last row are
     * the first and last rows inside of the
     * {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}.</p>
     * <p>For typical camera sensors that use rolling shutters, this is also equivalent
     * to the frame readout time.</p>
     * <p><b>Units</b>: Nanoseconds</p>
     * <p><b>Range of valid values:</b><br>
     * &gt;= 0 and &lt;
     * {@link android.hardware.camera2.params.StreamConfigurationMap#getOutputMinFrameDuration }.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Limited capability</b> -
     * Present on all camera devices that report being at least {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED HARDWARE_LEVEL_LIMITED} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE
     */
    @PublicKey
    public static final Key<Long> SENSOR_ROLLING_SHUTTER_SKEW =
            new Key<Long>("android.sensor.rollingShutterSkew", long.class);

    /**
     * <p>Quality of lens shading correction applied
     * to the image data.</p>
     * <p>When set to OFF mode, no lens shading correction will be applied by the
     * camera device, and an identity lens shading map data will be provided
     * if <code>{@link CaptureRequest#STATISTICS_LENS_SHADING_MAP_MODE android.statistics.lensShadingMapMode} == ON</code>. For example, for lens
     * shading map with size of <code>[ 4, 3 ]</code>,
     * the output {@link CaptureResult#STATISTICS_LENS_SHADING_CORRECTION_MAP android.statistics.lensShadingCorrectionMap} for this case will be an identity
     * map shown below:</p>
     * <pre><code>[ 1.0, 1.0, 1.0, 1.0,  1.0, 1.0, 1.0, 1.0,
     *  1.0, 1.0, 1.0, 1.0,  1.0, 1.0, 1.0, 1.0,
     *  1.0, 1.0, 1.0, 1.0,  1.0, 1.0, 1.0, 1.0,
     *  1.0, 1.0, 1.0, 1.0,  1.0, 1.0, 1.0, 1.0,
     *  1.0, 1.0, 1.0, 1.0,  1.0, 1.0, 1.0, 1.0,
     *  1.0, 1.0, 1.0, 1.0,  1.0, 1.0, 1.0, 1.0 ]
     * </code></pre>
     * <p>When set to other modes, lens shading correction will be applied by the camera
     * device. Applications can request lens shading map data by setting
     * {@link CaptureRequest#STATISTICS_LENS_SHADING_MAP_MODE android.statistics.lensShadingMapMode} to ON, and then the camera device will provide lens
     * shading map data in {@link CaptureResult#STATISTICS_LENS_SHADING_CORRECTION_MAP android.statistics.lensShadingCorrectionMap}; the returned shading map
     * data will be the one applied by the camera device for this capture request.</p>
     * <p>The shading map data may depend on the auto-exposure (AE) and AWB statistics, therefore
     * the reliability of the map data may be affected by the AE and AWB algorithms. When AE and
     * AWB are in AUTO modes({@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} <code>!=</code> OFF and {@link CaptureRequest#CONTROL_AWB_MODE android.control.awbMode} <code>!=</code>
     * OFF), to get best results, it is recommended that the applications wait for the AE and AWB
     * to be converged before using the returned shading map data.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #SHADING_MODE_OFF OFF}</li>
     *   <li>{@link #SHADING_MODE_FAST FAST}</li>
     *   <li>{@link #SHADING_MODE_HIGH_QUALITY HIGH_QUALITY}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#SHADING_AVAILABLE_MODES android.shading.availableModes}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CaptureRequest#CONTROL_AWB_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#SHADING_AVAILABLE_MODES
     * @see CaptureResult#STATISTICS_LENS_SHADING_CORRECTION_MAP
     * @see CaptureRequest#STATISTICS_LENS_SHADING_MAP_MODE
     * @see #SHADING_MODE_OFF
     * @see #SHADING_MODE_FAST
     * @see #SHADING_MODE_HIGH_QUALITY
     */
    @PublicKey
    public static final Key<Integer> SHADING_MODE =
            new Key<Integer>("android.shading.mode", int.class);

    /**
     * <p>Operating mode for the face detector
     * unit.</p>
     * <p>Whether face detection is enabled, and whether it
     * should output just the basic fields or the full set of
     * fields.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #STATISTICS_FACE_DETECT_MODE_OFF OFF}</li>
     *   <li>{@link #STATISTICS_FACE_DETECT_MODE_SIMPLE SIMPLE}</li>
     *   <li>{@link #STATISTICS_FACE_DETECT_MODE_FULL FULL}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#STATISTICS_INFO_AVAILABLE_FACE_DETECT_MODES android.statistics.info.availableFaceDetectModes}</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#STATISTICS_INFO_AVAILABLE_FACE_DETECT_MODES
     * @see #STATISTICS_FACE_DETECT_MODE_OFF
     * @see #STATISTICS_FACE_DETECT_MODE_SIMPLE
     * @see #STATISTICS_FACE_DETECT_MODE_FULL
     */
    @PublicKey
    public static final Key<Integer> STATISTICS_FACE_DETECT_MODE =
            new Key<Integer>("android.statistics.faceDetectMode", int.class);

    /**
     * <p>List of unique IDs for detected faces.</p>
     * <p>Each detected face is given a unique ID that is valid for as long as the face is visible
     * to the camera device.  A face that leaves the field of view and later returns may be
     * assigned a new ID.</p>
     * <p>Only available if {@link CaptureRequest#STATISTICS_FACE_DETECT_MODE android.statistics.faceDetectMode} == FULL
     * This key is available on all devices.</p>
     *
     * @see CaptureRequest#STATISTICS_FACE_DETECT_MODE
     * @hide
     */
    public static final Key<int[]> STATISTICS_FACE_IDS =
            new Key<int[]>("android.statistics.faceIds", int[].class);

    /**
     * <p>List of landmarks for detected
     * faces.</p>
     * <p>The coordinate system is that of {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}, with
     * <code>(0, 0)</code> being the top-left pixel of the active array.</p>
     * <p>Only available if {@link CaptureRequest#STATISTICS_FACE_DETECT_MODE android.statistics.faceDetectMode} == FULL
     * This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE
     * @see CaptureRequest#STATISTICS_FACE_DETECT_MODE
     * @hide
     */
    public static final Key<int[]> STATISTICS_FACE_LANDMARKS =
            new Key<int[]>("android.statistics.faceLandmarks", int[].class);

    /**
     * <p>List of the bounding rectangles for detected
     * faces.</p>
     * <p>The coordinate system is that of {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}, with
     * <code>(0, 0)</code> being the top-left pixel of the active array.</p>
     * <p>Only available if {@link CaptureRequest#STATISTICS_FACE_DETECT_MODE android.statistics.faceDetectMode} != OFF
     * This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE
     * @see CaptureRequest#STATISTICS_FACE_DETECT_MODE
     * @hide
     */
    public static final Key<android.graphics.Rect[]> STATISTICS_FACE_RECTANGLES =
            new Key<android.graphics.Rect[]>("android.statistics.faceRectangles", android.graphics.Rect[].class);

    /**
     * <p>List of the face confidence scores for
     * detected faces</p>
     * <p>Only available if {@link CaptureRequest#STATISTICS_FACE_DETECT_MODE android.statistics.faceDetectMode} != OFF.</p>
     * <p><b>Range of valid values:</b><br>
     * 1-100</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#STATISTICS_FACE_DETECT_MODE
     * @hide
     */
    public static final Key<byte[]> STATISTICS_FACE_SCORES =
            new Key<byte[]>("android.statistics.faceScores", byte[].class);

    /**
     * <p>List of the faces detected through camera face detection
     * in this capture.</p>
     * <p>Only available if {@link CaptureRequest#STATISTICS_FACE_DETECT_MODE android.statistics.faceDetectMode} <code>!=</code> OFF.</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CaptureRequest#STATISTICS_FACE_DETECT_MODE
     */
    @PublicKey
    @SyntheticKey
    public static final Key<android.hardware.camera2.params.Face[]> STATISTICS_FACES =
            new Key<android.hardware.camera2.params.Face[]>("android.statistics.faces", android.hardware.camera2.params.Face[].class);

    /**
     * <p>The shading map is a low-resolution floating-point map
     * that lists the coefficients used to correct for vignetting, for each
     * Bayer color channel.</p>
     * <p>The least shaded section of the image should have a gain factor
     * of 1; all other sections should have gains above 1.</p>
     * <p>When {@link CaptureRequest#COLOR_CORRECTION_MODE android.colorCorrection.mode} = TRANSFORM_MATRIX, the map
     * must take into account the colorCorrection settings.</p>
     * <p>The shading map is for the entire active pixel array, and is not
     * affected by the crop region specified in the request. Each shading map
     * entry is the value of the shading compensation map over a specific
     * pixel on the sensor.  Specifically, with a (N x M) resolution shading
     * map, and an active pixel array size (W x H), shading map entry
     * (x,y) ϵ (0 ... N-1, 0 ... M-1) is the value of the shading map at
     * pixel ( ((W-1)/(N-1)) * x, ((H-1)/(M-1)) * y) for the four color channels.
     * The map is assumed to be bilinearly interpolated between the sample points.</p>
     * <p>The channel order is [R, Geven, Godd, B], where Geven is the green
     * channel for the even rows of a Bayer pattern, and Godd is the odd rows.
     * The shading map is stored in a fully interleaved format.</p>
     * <p>The shading map should have on the order of 30-40 rows and columns,
     * and must be smaller than 64x64.</p>
     * <p>As an example, given a very small map defined as:</p>
     * <pre><code>width,height = [ 4, 3 ]
     * values =
     * [ 1.3, 1.2, 1.15, 1.2,  1.2, 1.2, 1.15, 1.2,
     *     1.1, 1.2, 1.2, 1.2,  1.3, 1.2, 1.3, 1.3,
     *   1.2, 1.2, 1.25, 1.1,  1.1, 1.1, 1.1, 1.0,
     *     1.0, 1.0, 1.0, 1.0,  1.2, 1.3, 1.25, 1.2,
     *   1.3, 1.2, 1.2, 1.3,   1.2, 1.15, 1.1, 1.2,
     *     1.2, 1.1, 1.0, 1.2,  1.3, 1.15, 1.2, 1.3 ]
     * </code></pre>
     * <p>The low-resolution scaling map images for each channel are
     * (displayed using nearest-neighbor interpolation):</p>
     * <p><img alt="Red lens shading map" src="../../../../images/camera2/metadata/android.statistics.lensShadingMap/red_shading.png" />
     * <img alt="Green (even rows) lens shading map" src="../../../../images/camera2/metadata/android.statistics.lensShadingMap/green_e_shading.png" />
     * <img alt="Green (odd rows) lens shading map" src="../../../../images/camera2/metadata/android.statistics.lensShadingMap/green_o_shading.png" />
     * <img alt="Blue lens shading map" src="../../../../images/camera2/metadata/android.statistics.lensShadingMap/blue_shading.png" /></p>
     * <p>As a visualization only, inverting the full-color map to recover an
     * image of a gray wall (using bicubic interpolation for visual quality) as captured by the sensor gives:</p>
     * <p><img alt="Image of a uniform white wall (inverse shading map)" src="../../../../images/camera2/metadata/android.statistics.lensShadingMap/inv_shading.png" /></p>
     * <p><b>Range of valid values:</b><br>
     * Each gain factor is &gt;= 1</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#COLOR_CORRECTION_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     */
    @PublicKey
    public static final Key<android.hardware.camera2.params.LensShadingMap> STATISTICS_LENS_SHADING_CORRECTION_MAP =
            new Key<android.hardware.camera2.params.LensShadingMap>("android.statistics.lensShadingCorrectionMap", android.hardware.camera2.params.LensShadingMap.class);

    /**
     * <p>The shading map is a low-resolution floating-point map
     * that lists the coefficients used to correct for vignetting, for each
     * Bayer color channel of RAW image data.</p>
     * <p>The least shaded section of the image should have a gain factor
     * of 1; all other sections should have gains above 1.</p>
     * <p>When {@link CaptureRequest#COLOR_CORRECTION_MODE android.colorCorrection.mode} = TRANSFORM_MATRIX, the map
     * must take into account the colorCorrection settings.</p>
     * <p>The shading map is for the entire active pixel array, and is not
     * affected by the crop region specified in the request. Each shading map
     * entry is the value of the shading compensation map over a specific
     * pixel on the sensor.  Specifically, with a (N x M) resolution shading
     * map, and an active pixel array size (W x H), shading map entry
     * (x,y) ϵ (0 ... N-1, 0 ... M-1) is the value of the shading map at
     * pixel ( ((W-1)/(N-1)) * x, ((H-1)/(M-1)) * y) for the four color channels.
     * The map is assumed to be bilinearly interpolated between the sample points.</p>
     * <p>The channel order is [R, Geven, Godd, B], where Geven is the green
     * channel for the even rows of a Bayer pattern, and Godd is the odd rows.
     * The shading map is stored in a fully interleaved format, and its size
     * is provided in the camera static metadata by android.lens.info.shadingMapSize.</p>
     * <p>The shading map should have on the order of 30-40 rows and columns,
     * and must be smaller than 64x64.</p>
     * <p>As an example, given a very small map defined as:</p>
     * <pre><code>android.lens.info.shadingMapSize = [ 4, 3 ]
     * android.statistics.lensShadingMap =
     * [ 1.3, 1.2, 1.15, 1.2,  1.2, 1.2, 1.15, 1.2,
     *     1.1, 1.2, 1.2, 1.2,  1.3, 1.2, 1.3, 1.3,
     *   1.2, 1.2, 1.25, 1.1,  1.1, 1.1, 1.1, 1.0,
     *     1.0, 1.0, 1.0, 1.0,  1.2, 1.3, 1.25, 1.2,
     *   1.3, 1.2, 1.2, 1.3,   1.2, 1.15, 1.1, 1.2,
     *     1.2, 1.1, 1.0, 1.2,  1.3, 1.15, 1.2, 1.3 ]
     * </code></pre>
     * <p>The low-resolution scaling map images for each channel are
     * (displayed using nearest-neighbor interpolation):</p>
     * <p><img alt="Red lens shading map" src="../../../../images/camera2/metadata/android.statistics.lensShadingMap/red_shading.png" />
     * <img alt="Green (even rows) lens shading map" src="../../../../images/camera2/metadata/android.statistics.lensShadingMap/green_e_shading.png" />
     * <img alt="Green (odd rows) lens shading map" src="../../../../images/camera2/metadata/android.statistics.lensShadingMap/green_o_shading.png" />
     * <img alt="Blue lens shading map" src="../../../../images/camera2/metadata/android.statistics.lensShadingMap/blue_shading.png" /></p>
     * <p>As a visualization only, inverting the full-color map to recover an
     * image of a gray wall (using bicubic interpolation for visual quality)
     * as captured by the sensor gives:</p>
     * <p><img alt="Image of a uniform white wall (inverse shading map)" src="../../../../images/camera2/metadata/android.statistics.lensShadingMap/inv_shading.png" /></p>
     * <p>Note that the RAW image data might be subject to lens shading
     * correction not reported on this map. Query
     * {@link CameraCharacteristics#SENSOR_INFO_LENS_SHADING_APPLIED android.sensor.info.lensShadingApplied} to see if RAW image data has subject
     * to lens shading correction. If {@link CameraCharacteristics#SENSOR_INFO_LENS_SHADING_APPLIED android.sensor.info.lensShadingApplied}
     * is TRUE, the RAW image data is subject to partial or full lens shading
     * correction. In the case full lens shading correction is applied to RAW
     * images, the gain factor map reported in this key will contain all 1.0 gains.
     * In other words, the map reported in this key is the remaining lens shading
     * that needs to be applied on the RAW image to get images without lens shading
     * artifacts. See {@link CameraCharacteristics#REQUEST_MAX_NUM_OUTPUT_RAW android.request.maxNumOutputRaw} for a list of RAW image
     * formats.</p>
     * <p><b>Range of valid values:</b><br>
     * Each gain factor is &gt;= 1</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#COLOR_CORRECTION_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#REQUEST_MAX_NUM_OUTPUT_RAW
     * @see CameraCharacteristics#SENSOR_INFO_LENS_SHADING_APPLIED
     * @hide
     */
    public static final Key<float[]> STATISTICS_LENS_SHADING_MAP =
            new Key<float[]>("android.statistics.lensShadingMap", float[].class);

    /**
     * <p>The best-fit color channel gains calculated
     * by the camera device's statistics units for the current output frame.</p>
     * <p>This may be different than the gains used for this frame,
     * since statistics processing on data from a new frame
     * typically completes after the transform has already been
     * applied to that frame.</p>
     * <p>The 4 channel gains are defined in Bayer domain,
     * see {@link CaptureRequest#COLOR_CORRECTION_GAINS android.colorCorrection.gains} for details.</p>
     * <p>This value should always be calculated by the auto-white balance (AWB) block,
     * regardless of the android.control.* current values.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CaptureRequest#COLOR_CORRECTION_GAINS
     * @deprecated
     * @hide
     */
    @Deprecated
    public static final Key<float[]> STATISTICS_PREDICTED_COLOR_GAINS =
            new Key<float[]>("android.statistics.predictedColorGains", float[].class);

    /**
     * <p>The best-fit color transform matrix estimate
     * calculated by the camera device's statistics units for the current
     * output frame.</p>
     * <p>The camera device will provide the estimate from its
     * statistics unit on the white balance transforms to use
     * for the next frame. These are the values the camera device believes
     * are the best fit for the current output frame. This may
     * be different than the transform used for this frame, since
     * statistics processing on data from a new frame typically
     * completes after the transform has already been applied to
     * that frame.</p>
     * <p>These estimates must be provided for all frames, even if
     * capture settings and color transforms are set by the application.</p>
     * <p>This value should always be calculated by the auto-white balance (AWB) block,
     * regardless of the android.control.* current values.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * @deprecated
     * @hide
     */
    @Deprecated
    public static final Key<Rational[]> STATISTICS_PREDICTED_COLOR_TRANSFORM =
            new Key<Rational[]>("android.statistics.predictedColorTransform", Rational[].class);

    /**
     * <p>The camera device estimated scene illumination lighting
     * frequency.</p>
     * <p>Many light sources, such as most fluorescent lights, flicker at a rate
     * that depends on the local utility power standards. This flicker must be
     * accounted for by auto-exposure routines to avoid artifacts in captured images.
     * The camera device uses this entry to tell the application what the scene
     * illuminant frequency is.</p>
     * <p>When manual exposure control is enabled
     * (<code>{@link CaptureRequest#CONTROL_AE_MODE android.control.aeMode} == OFF</code> or <code>{@link CaptureRequest#CONTROL_MODE android.control.mode} ==
     * OFF</code>), the {@link CaptureRequest#CONTROL_AE_ANTIBANDING_MODE android.control.aeAntibandingMode} doesn't perform
     * antibanding, and the application can ensure it selects
     * exposure times that do not cause banding issues by looking
     * into this metadata field. See
     * {@link CaptureRequest#CONTROL_AE_ANTIBANDING_MODE android.control.aeAntibandingMode} for more details.</p>
     * <p>Reports NONE if there doesn't appear to be flickering illumination.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #STATISTICS_SCENE_FLICKER_NONE NONE}</li>
     *   <li>{@link #STATISTICS_SCENE_FLICKER_50HZ 50HZ}</li>
     *   <li>{@link #STATISTICS_SCENE_FLICKER_60HZ 60HZ}</li>
     * </ul></p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#CONTROL_AE_ANTIBANDING_MODE
     * @see CaptureRequest#CONTROL_AE_MODE
     * @see CaptureRequest#CONTROL_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see #STATISTICS_SCENE_FLICKER_NONE
     * @see #STATISTICS_SCENE_FLICKER_50HZ
     * @see #STATISTICS_SCENE_FLICKER_60HZ
     */
    @PublicKey
    public static final Key<Integer> STATISTICS_SCENE_FLICKER =
            new Key<Integer>("android.statistics.sceneFlicker", int.class);

    /**
     * <p>Operating mode for hot pixel map generation.</p>
     * <p>If set to <code>true</code>, a hot pixel map is returned in {@link CaptureResult#STATISTICS_HOT_PIXEL_MAP android.statistics.hotPixelMap}.
     * If set to <code>false</code>, no hot pixel map will be returned.</p>
     * <p><b>Range of valid values:</b><br>
     * {@link CameraCharacteristics#STATISTICS_INFO_AVAILABLE_HOT_PIXEL_MAP_MODES android.statistics.info.availableHotPixelMapModes}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CaptureResult#STATISTICS_HOT_PIXEL_MAP
     * @see CameraCharacteristics#STATISTICS_INFO_AVAILABLE_HOT_PIXEL_MAP_MODES
     */
    @PublicKey
    public static final Key<Boolean> STATISTICS_HOT_PIXEL_MAP_MODE =
            new Key<Boolean>("android.statistics.hotPixelMapMode", boolean.class);

    /**
     * <p>List of <code>(x, y)</code> coordinates of hot/defective pixels on the sensor.</p>
     * <p>A coordinate <code>(x, y)</code> must lie between <code>(0, 0)</code>, and
     * <code>(width - 1, height - 1)</code> (inclusive), which are the top-left and
     * bottom-right of the pixel array, respectively. The width and
     * height dimensions are given in {@link CameraCharacteristics#SENSOR_INFO_PIXEL_ARRAY_SIZE android.sensor.info.pixelArraySize}.
     * This may include hot pixels that lie outside of the active array
     * bounds given by {@link CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE android.sensor.info.activeArraySize}.</p>
     * <p><b>Range of valid values:</b><br></p>
     * <p>n &lt;= number of pixels on the sensor.
     * The <code>(x, y)</code> coordinates must be bounded by
     * {@link CameraCharacteristics#SENSOR_INFO_PIXEL_ARRAY_SIZE android.sensor.info.pixelArraySize}.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CameraCharacteristics#SENSOR_INFO_ACTIVE_ARRAY_SIZE
     * @see CameraCharacteristics#SENSOR_INFO_PIXEL_ARRAY_SIZE
     */
    @PublicKey
    public static final Key<android.graphics.Point[]> STATISTICS_HOT_PIXEL_MAP =
            new Key<android.graphics.Point[]>("android.statistics.hotPixelMap", android.graphics.Point[].class);

    /**
     * <p>Whether the camera device will output the lens
     * shading map in output result metadata.</p>
     * <p>When set to ON,
     * android.statistics.lensShadingMap will be provided in
     * the output result metadata.</p>
     * <p>ON is always supported on devices with the RAW capability.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #STATISTICS_LENS_SHADING_MAP_MODE_OFF OFF}</li>
     *   <li>{@link #STATISTICS_LENS_SHADING_MAP_MODE_ON ON}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#STATISTICS_INFO_AVAILABLE_LENS_SHADING_MAP_MODES android.statistics.info.availableLensShadingMapModes}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#STATISTICS_INFO_AVAILABLE_LENS_SHADING_MAP_MODES
     * @see #STATISTICS_LENS_SHADING_MAP_MODE_OFF
     * @see #STATISTICS_LENS_SHADING_MAP_MODE_ON
     */
    @PublicKey
    public static final Key<Integer> STATISTICS_LENS_SHADING_MAP_MODE =
            new Key<Integer>("android.statistics.lensShadingMapMode", int.class);

    /**
     * <p>Tonemapping / contrast / gamma curve for the blue
     * channel, to use when {@link CaptureRequest#TONEMAP_MODE android.tonemap.mode} is
     * CONTRAST_CURVE.</p>
     * <p>See android.tonemap.curveRed for more details.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CaptureRequest#TONEMAP_MODE
     * @hide
     */
    public static final Key<float[]> TONEMAP_CURVE_BLUE =
            new Key<float[]>("android.tonemap.curveBlue", float[].class);

    /**
     * <p>Tonemapping / contrast / gamma curve for the green
     * channel, to use when {@link CaptureRequest#TONEMAP_MODE android.tonemap.mode} is
     * CONTRAST_CURVE.</p>
     * <p>See android.tonemap.curveRed for more details.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CaptureRequest#TONEMAP_MODE
     * @hide
     */
    public static final Key<float[]> TONEMAP_CURVE_GREEN =
            new Key<float[]>("android.tonemap.curveGreen", float[].class);

    /**
     * <p>Tonemapping / contrast / gamma curve for the red
     * channel, to use when {@link CaptureRequest#TONEMAP_MODE android.tonemap.mode} is
     * CONTRAST_CURVE.</p>
     * <p>Each channel's curve is defined by an array of control points:</p>
     * <pre><code>android.tonemap.curveRed =
     *   [ P0in, P0out, P1in, P1out, P2in, P2out, P3in, P3out, ..., PNin, PNout ]
     * 2 &lt;= N &lt;= {@link CameraCharacteristics#TONEMAP_MAX_CURVE_POINTS android.tonemap.maxCurvePoints}</code></pre>
     * <p>These are sorted in order of increasing <code>Pin</code>; it is
     * required that input values 0.0 and 1.0 are included in the list to
     * define a complete mapping. For input values between control points,
     * the camera device must linearly interpolate between the control
     * points.</p>
     * <p>Each curve can have an independent number of points, and the number
     * of points can be less than max (that is, the request doesn't have to
     * always provide a curve with number of points equivalent to
     * {@link CameraCharacteristics#TONEMAP_MAX_CURVE_POINTS android.tonemap.maxCurvePoints}).</p>
     * <p>A few examples, and their corresponding graphical mappings; these
     * only specify the red channel and the precision is limited to 4
     * digits, for conciseness.</p>
     * <p>Linear mapping:</p>
     * <pre><code>android.tonemap.curveRed = [ 0, 0, 1.0, 1.0 ]
     * </code></pre>
     * <p><img alt="Linear mapping curve" src="../../../../images/camera2/metadata/android.tonemap.curveRed/linear_tonemap.png" /></p>
     * <p>Invert mapping:</p>
     * <pre><code>android.tonemap.curveRed = [ 0, 1.0, 1.0, 0 ]
     * </code></pre>
     * <p><img alt="Inverting mapping curve" src="../../../../images/camera2/metadata/android.tonemap.curveRed/inverse_tonemap.png" /></p>
     * <p>Gamma 1/2.2 mapping, with 16 control points:</p>
     * <pre><code>android.tonemap.curveRed = [
     *   0.0000, 0.0000, 0.0667, 0.2920, 0.1333, 0.4002, 0.2000, 0.4812,
     *   0.2667, 0.5484, 0.3333, 0.6069, 0.4000, 0.6594, 0.4667, 0.7072,
     *   0.5333, 0.7515, 0.6000, 0.7928, 0.6667, 0.8317, 0.7333, 0.8685,
     *   0.8000, 0.9035, 0.8667, 0.9370, 0.9333, 0.9691, 1.0000, 1.0000 ]
     * </code></pre>
     * <p><img alt="Gamma = 1/2.2 tonemapping curve" src="../../../../images/camera2/metadata/android.tonemap.curveRed/gamma_tonemap.png" /></p>
     * <p>Standard sRGB gamma mapping, per IEC 61966-2-1:1999, with 16 control points:</p>
     * <pre><code>android.tonemap.curveRed = [
     *   0.0000, 0.0000, 0.0667, 0.2864, 0.1333, 0.4007, 0.2000, 0.4845,
     *   0.2667, 0.5532, 0.3333, 0.6125, 0.4000, 0.6652, 0.4667, 0.7130,
     *   0.5333, 0.7569, 0.6000, 0.7977, 0.6667, 0.8360, 0.7333, 0.8721,
     *   0.8000, 0.9063, 0.8667, 0.9389, 0.9333, 0.9701, 1.0000, 1.0000 ]
     * </code></pre>
     * <p><img alt="sRGB tonemapping curve" src="../../../../images/camera2/metadata/android.tonemap.curveRed/srgb_tonemap.png" /></p>
     * <p><b>Range of valid values:</b><br>
     * 0-1 on both input and output coordinates, normalized
     * as a floating-point value such that 0 == black and 1 == white.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#TONEMAP_MAX_CURVE_POINTS
     * @see CaptureRequest#TONEMAP_MODE
     * @hide
     */
    public static final Key<float[]> TONEMAP_CURVE_RED =
            new Key<float[]>("android.tonemap.curveRed", float[].class);

    /**
     * <p>Tonemapping / contrast / gamma curve to use when {@link CaptureRequest#TONEMAP_MODE android.tonemap.mode}
     * is CONTRAST_CURVE.</p>
     * <p>The tonemapCurve consist of three curves for each of red, green, and blue
     * channels respectively. The following example uses the red channel as an
     * example. The same logic applies to green and blue channel.
     * Each channel's curve is defined by an array of control points:</p>
     * <pre><code>curveRed =
     *   [ P0(in, out), P1(in, out), P2(in, out), P3(in, out), ..., PN(in, out) ]
     * 2 &lt;= N &lt;= {@link CameraCharacteristics#TONEMAP_MAX_CURVE_POINTS android.tonemap.maxCurvePoints}</code></pre>
     * <p>These are sorted in order of increasing <code>Pin</code>; it is always
     * guaranteed that input values 0.0 and 1.0 are included in the list to
     * define a complete mapping. For input values between control points,
     * the camera device must linearly interpolate between the control
     * points.</p>
     * <p>Each curve can have an independent number of points, and the number
     * of points can be less than max (that is, the request doesn't have to
     * always provide a curve with number of points equivalent to
     * {@link CameraCharacteristics#TONEMAP_MAX_CURVE_POINTS android.tonemap.maxCurvePoints}).</p>
     * <p>A few examples, and their corresponding graphical mappings; these
     * only specify the red channel and the precision is limited to 4
     * digits, for conciseness.</p>
     * <p>Linear mapping:</p>
     * <pre><code>curveRed = [ (0, 0), (1.0, 1.0) ]
     * </code></pre>
     * <p><img alt="Linear mapping curve" src="../../../../images/camera2/metadata/android.tonemap.curveRed/linear_tonemap.png" /></p>
     * <p>Invert mapping:</p>
     * <pre><code>curveRed = [ (0, 1.0), (1.0, 0) ]
     * </code></pre>
     * <p><img alt="Inverting mapping curve" src="../../../../images/camera2/metadata/android.tonemap.curveRed/inverse_tonemap.png" /></p>
     * <p>Gamma 1/2.2 mapping, with 16 control points:</p>
     * <pre><code>curveRed = [
     *   (0.0000, 0.0000), (0.0667, 0.2920), (0.1333, 0.4002), (0.2000, 0.4812),
     *   (0.2667, 0.5484), (0.3333, 0.6069), (0.4000, 0.6594), (0.4667, 0.7072),
     *   (0.5333, 0.7515), (0.6000, 0.7928), (0.6667, 0.8317), (0.7333, 0.8685),
     *   (0.8000, 0.9035), (0.8667, 0.9370), (0.9333, 0.9691), (1.0000, 1.0000) ]
     * </code></pre>
     * <p><img alt="Gamma = 1/2.2 tonemapping curve" src="../../../../images/camera2/metadata/android.tonemap.curveRed/gamma_tonemap.png" /></p>
     * <p>Standard sRGB gamma mapping, per IEC 61966-2-1:1999, with 16 control points:</p>
     * <pre><code>curveRed = [
     *   (0.0000, 0.0000), (0.0667, 0.2864), (0.1333, 0.4007), (0.2000, 0.4845),
     *   (0.2667, 0.5532), (0.3333, 0.6125), (0.4000, 0.6652), (0.4667, 0.7130),
     *   (0.5333, 0.7569), (0.6000, 0.7977), (0.6667, 0.8360), (0.7333, 0.8721),
     *   (0.8000, 0.9063), (0.8667, 0.9389), (0.9333, 0.9701), (1.0000, 1.0000) ]
     * </code></pre>
     * <p><img alt="sRGB tonemapping curve" src="../../../../images/camera2/metadata/android.tonemap.curveRed/srgb_tonemap.png" /></p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#TONEMAP_MAX_CURVE_POINTS
     * @see CaptureRequest#TONEMAP_MODE
     */
    @PublicKey
    @SyntheticKey
    public static final Key<android.hardware.camera2.params.TonemapCurve> TONEMAP_CURVE =
            new Key<android.hardware.camera2.params.TonemapCurve>("android.tonemap.curve", android.hardware.camera2.params.TonemapCurve.class);

    /**
     * <p>High-level global contrast/gamma/tonemapping control.</p>
     * <p>When switching to an application-defined contrast curve by setting
     * {@link CaptureRequest#TONEMAP_MODE android.tonemap.mode} to CONTRAST_CURVE, the curve is defined
     * per-channel with a set of <code>(in, out)</code> points that specify the
     * mapping from input high-bit-depth pixel value to the output
     * low-bit-depth value.  Since the actual pixel ranges of both input
     * and output may change depending on the camera pipeline, the values
     * are specified by normalized floating-point numbers.</p>
     * <p>More-complex color mapping operations such as 3D color look-up
     * tables, selective chroma enhancement, or other non-linear color
     * transforms will be disabled when {@link CaptureRequest#TONEMAP_MODE android.tonemap.mode} is
     * CONTRAST_CURVE.</p>
     * <p>When using either FAST or HIGH_QUALITY, the camera device will
     * emit its own tonemap curve in {@link CaptureRequest#TONEMAP_CURVE android.tonemap.curve}.
     * These values are always available, and as close as possible to the
     * actually used nonlinear/nonglobal transforms.</p>
     * <p>If a request is sent with CONTRAST_CURVE with the camera device's
     * provided curve in FAST or HIGH_QUALITY, the image's tonemap will be
     * roughly the same.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #TONEMAP_MODE_CONTRAST_CURVE CONTRAST_CURVE}</li>
     *   <li>{@link #TONEMAP_MODE_FAST FAST}</li>
     *   <li>{@link #TONEMAP_MODE_HIGH_QUALITY HIGH_QUALITY}</li>
     *   <li>{@link #TONEMAP_MODE_GAMMA_VALUE GAMMA_VALUE}</li>
     *   <li>{@link #TONEMAP_MODE_PRESET_CURVE PRESET_CURVE}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * {@link CameraCharacteristics#TONEMAP_AVAILABLE_TONE_MAP_MODES android.tonemap.availableToneMapModes}</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CameraCharacteristics#TONEMAP_AVAILABLE_TONE_MAP_MODES
     * @see CaptureRequest#TONEMAP_CURVE
     * @see CaptureRequest#TONEMAP_MODE
     * @see #TONEMAP_MODE_CONTRAST_CURVE
     * @see #TONEMAP_MODE_FAST
     * @see #TONEMAP_MODE_HIGH_QUALITY
     * @see #TONEMAP_MODE_GAMMA_VALUE
     * @see #TONEMAP_MODE_PRESET_CURVE
     */
    @PublicKey
    public static final Key<Integer> TONEMAP_MODE =
            new Key<Integer>("android.tonemap.mode", int.class);

    /**
     * <p>Tonemapping curve to use when {@link CaptureRequest#TONEMAP_MODE android.tonemap.mode} is
     * GAMMA_VALUE</p>
     * <p>The tonemap curve will be defined the following formula:
     * * OUT = pow(IN, 1.0 / gamma)
     * where IN and OUT is the input pixel value scaled to range [0.0, 1.0],
     * pow is the power function and gamma is the gamma value specified by this
     * key.</p>
     * <p>The same curve will be applied to all color channels. The camera device
     * may clip the input gamma value to its supported range. The actual applied
     * value will be returned in capture result.</p>
     * <p>The valid range of gamma value varies on different devices, but values
     * within [1.0, 5.0] are guaranteed not to be clipped.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CaptureRequest#TONEMAP_MODE
     */
    @PublicKey
    public static final Key<Float> TONEMAP_GAMMA =
            new Key<Float>("android.tonemap.gamma", float.class);

    /**
     * <p>Tonemapping curve to use when {@link CaptureRequest#TONEMAP_MODE android.tonemap.mode} is
     * PRESET_CURVE</p>
     * <p>The tonemap curve will be defined by specified standard.</p>
     * <p>sRGB (approximated by 16 control points):</p>
     * <p><img alt="sRGB tonemapping curve" src="../../../../images/camera2/metadata/android.tonemap.curveRed/srgb_tonemap.png" /></p>
     * <p>Rec. 709 (approximated by 16 control points):</p>
     * <p><img alt="Rec. 709 tonemapping curve" src="../../../../images/camera2/metadata/android.tonemap.curveRed/rec709_tonemap.png" /></p>
     * <p>Note that above figures show a 16 control points approximation of preset
     * curves. Camera devices may apply a different approximation to the curve.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #TONEMAP_PRESET_CURVE_SRGB SRGB}</li>
     *   <li>{@link #TONEMAP_PRESET_CURVE_REC709 REC709}</li>
     * </ul></p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     *
     * @see CaptureRequest#TONEMAP_MODE
     * @see #TONEMAP_PRESET_CURVE_SRGB
     * @see #TONEMAP_PRESET_CURVE_REC709
     */
    @PublicKey
    public static final Key<Integer> TONEMAP_PRESET_CURVE =
            new Key<Integer>("android.tonemap.presetCurve", int.class);

    /**
     * <p>This LED is nominally used to indicate to the user
     * that the camera is powered on and may be streaming images back to the
     * Application Processor. In certain rare circumstances, the OS may
     * disable this when video is processed locally and not transmitted to
     * any untrusted applications.</p>
     * <p>In particular, the LED <em>must</em> always be on when the data could be
     * transmitted off the device. The LED <em>should</em> always be on whenever
     * data is stored locally on the device.</p>
     * <p>The LED <em>may</em> be off if a trusted application is using the data that
     * doesn't violate the above rules.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * @hide
     */
    public static final Key<Boolean> LED_TRANSMIT =
            new Key<Boolean>("android.led.transmit", boolean.class);

    /**
     * <p>Whether black-level compensation is locked
     * to its current values, or is free to vary.</p>
     * <p>Whether the black level offset was locked for this frame.  Should be
     * ON if {@link CaptureRequest#BLACK_LEVEL_LOCK android.blackLevel.lock} was ON in the capture request, unless
     * a change in other capture settings forced the camera device to
     * perform a black level reset.</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Full capability</b> -
     * Present on all camera devices that report being {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_FULL HARDWARE_LEVEL_FULL} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#BLACK_LEVEL_LOCK
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     */
    @PublicKey
    public static final Key<Boolean> BLACK_LEVEL_LOCK =
            new Key<Boolean>("android.blackLevel.lock", boolean.class);

    /**
     * <p>The frame number corresponding to the last request
     * with which the output result (metadata + buffers) has been fully
     * synchronized.</p>
     * <p>When a request is submitted to the camera device, there is usually a
     * delay of several frames before the controls get applied. A camera
     * device may either choose to account for this delay by implementing a
     * pipeline and carefully submit well-timed atomic control updates, or
     * it may start streaming control changes that span over several frame
     * boundaries.</p>
     * <p>In the latter case, whenever a request's settings change relative to
     * the previous submitted request, the full set of changes may take
     * multiple frame durations to fully take effect. Some settings may
     * take effect sooner (in less frame durations) than others.</p>
     * <p>While a set of control changes are being propagated, this value
     * will be CONVERGING.</p>
     * <p>Once it is fully known that a set of control changes have been
     * finished propagating, and the resulting updated control settings
     * have been read back by the camera device, this value will be set
     * to a non-negative frame number (corresponding to the request to
     * which the results have synchronized to).</p>
     * <p>Older camera device implementations may not have a way to detect
     * when all camera controls have been applied, and will always set this
     * value to UNKNOWN.</p>
     * <p>FULL capability devices will always have this value set to the
     * frame number of the request corresponding to this result.</p>
     * <p><em>Further details</em>:</p>
     * <ul>
     * <li>Whenever a request differs from the last request, any future
     * results not yet returned may have this value set to CONVERGING (this
     * could include any in-progress captures not yet returned by the camera
     * device, for more details see pipeline considerations below).</li>
     * <li>Submitting a series of multiple requests that differ from the
     * previous request (e.g. r1, r2, r3 s.t. r1 != r2 != r3)
     * moves the new synchronization frame to the last non-repeating
     * request (using the smallest frame number from the contiguous list of
     * repeating requests).</li>
     * <li>Submitting the same request repeatedly will not change this value
     * to CONVERGING, if it was already a non-negative value.</li>
     * <li>When this value changes to non-negative, that means that all of the
     * metadata controls from the request have been applied, all of the
     * metadata controls from the camera device have been read to the
     * updated values (into the result), and all of the graphics buffers
     * corresponding to this result are also synchronized to the request.</li>
     * </ul>
     * <p><em>Pipeline considerations</em>:</p>
     * <p>Submitting a request with updated controls relative to the previously
     * submitted requests may also invalidate the synchronization state
     * of all the results corresponding to currently in-flight requests.</p>
     * <p>In other words, results for this current request and up to
     * {@link CameraCharacteristics#REQUEST_PIPELINE_MAX_DEPTH android.request.pipelineMaxDepth} prior requests may have their
     * android.sync.frameNumber change to CONVERGING.</p>
     * <p><b>Possible values:</b>
     * <ul>
     *   <li>{@link #SYNC_FRAME_NUMBER_CONVERGING CONVERGING}</li>
     *   <li>{@link #SYNC_FRAME_NUMBER_UNKNOWN UNKNOWN}</li>
     * </ul></p>
     * <p><b>Available values for this device:</b><br>
     * Either a non-negative value corresponding to a
     * <code>frame_number</code>, or one of the two enums (CONVERGING / UNKNOWN).</p>
     * <p>This key is available on all devices.</p>
     *
     * @see CameraCharacteristics#REQUEST_PIPELINE_MAX_DEPTH
     * @see #SYNC_FRAME_NUMBER_CONVERGING
     * @see #SYNC_FRAME_NUMBER_UNKNOWN
     * @hide
     */
    public static final Key<Long> SYNC_FRAME_NUMBER =
            new Key<Long>("android.sync.frameNumber", long.class);

    /**
     * <p>The amount of exposure time increase factor applied to the original output
     * frame by the application processing before sending for reprocessing.</p>
     * <p>This is optional, and will be supported if the camera device supports YUV_REPROCESSING
     * capability ({@link CameraCharacteristics#REQUEST_AVAILABLE_CAPABILITIES android.request.availableCapabilities} contains YUV_REPROCESSING).</p>
     * <p>For some YUV reprocessing use cases, the application may choose to filter the original
     * output frames to effectively reduce the noise to the same level as a frame that was
     * captured with longer exposure time. To be more specific, assuming the original captured
     * images were captured with a sensitivity of S and an exposure time of T, the model in
     * the camera device is that the amount of noise in the image would be approximately what
     * would be expected if the original capture parameters had been a sensitivity of
     * S/effectiveExposureFactor and an exposure time of T*effectiveExposureFactor, rather
     * than S and T respectively. If the captured images were processed by the application
     * before being sent for reprocessing, then the application may have used image processing
     * algorithms and/or multi-frame image fusion to reduce the noise in the
     * application-processed images (input images). By using the effectiveExposureFactor
     * control, the application can communicate to the camera device the actual noise level
     * improvement in the application-processed image. With this information, the camera
     * device can select appropriate noise reduction and edge enhancement parameters to avoid
     * excessive noise reduction ({@link CaptureRequest#NOISE_REDUCTION_MODE android.noiseReduction.mode}) and insufficient edge
     * enhancement ({@link CaptureRequest#EDGE_MODE android.edge.mode}) being applied to the reprocessed frames.</p>
     * <p>For example, for multi-frame image fusion use case, the application may fuse
     * multiple output frames together to a final frame for reprocessing. When N image are
     * fused into 1 image for reprocessing, the exposure time increase factor could be up to
     * square root of N (based on a simple photon shot noise model). The camera device will
     * adjust the reprocessing noise reduction and edge enhancement parameters accordingly to
     * produce the best quality images.</p>
     * <p>This is relative factor, 1.0 indicates the application hasn't processed the input
     * buffer in a way that affects its effective exposure time.</p>
     * <p>This control is only effective for YUV reprocessing capture request. For noise
     * reduction reprocessing, it is only effective when <code>{@link CaptureRequest#NOISE_REDUCTION_MODE android.noiseReduction.mode} != OFF</code>.
     * Similarly, for edge enhancement reprocessing, it is only effective when
     * <code>{@link CaptureRequest#EDGE_MODE android.edge.mode} != OFF</code>.</p>
     * <p><b>Units</b>: Relative exposure time increase factor.</p>
     * <p><b>Range of valid values:</b><br>
     * &gt;= 1.0</p>
     * <p><b>Optional</b> - This value may be {@code null} on some devices.</p>
     * <p><b>Limited capability</b> -
     * Present on all camera devices that report being at least {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL_LIMITED HARDWARE_LEVEL_LIMITED} devices in the
     * {@link CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL android.info.supportedHardwareLevel} key</p>
     *
     * @see CaptureRequest#EDGE_MODE
     * @see CameraCharacteristics#INFO_SUPPORTED_HARDWARE_LEVEL
     * @see CaptureRequest#NOISE_REDUCTION_MODE
     * @see CameraCharacteristics#REQUEST_AVAILABLE_CAPABILITIES
     */
    @PublicKey
    public static final Key<Float> REPROCESS_EFFECTIVE_EXPOSURE_FACTOR =
            new Key<Float>("android.reprocess.effectiveExposureFactor", float.class);

    /*~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~
     * End generated code
     *~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~@~O@*/



}
