MpPreview/app/src/main/java/com/xypower/mppreview/Camera2RawFragment.java

package com.xypower.mppreview;

import static com.xypower.mppreview.HdrUtil.generateTimestamp;
import static java.lang.System.loadLibrary;

import android.Manifest;
import android.app.Activity;
import android.app.Dialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.pm.PackageManager;
import android.graphics.ImageFormat;
import android.graphics.Matrix;
import android.graphics.Point;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.SurfaceTexture;
import android.hardware.SensorManager;
import android.hardware.camera2.CameraAccessException;
import android.hardware.camera2.CameraCaptureSession;
import android.hardware.camera2.CameraCharacteristics;
import android.hardware.camera2.CameraDevice;
import android.hardware.camera2.CameraManager;
import android.hardware.camera2.CameraMetadata;
import android.hardware.camera2.CaptureFailure;
import android.hardware.camera2.CaptureRequest;
import android.hardware.camera2.CaptureResult;
import android.hardware.camera2.TotalCaptureResult;
import android.hardware.camera2.params.MeteringRectangle;
import android.hardware.camera2.params.StreamConfigurationMap;
import android.media.Image;
import android.media.ImageReader;
import android.os.AsyncTask;
import android.os.Bundle;

import androidx.appcompat.app.AlertDialog;
import androidx.fragment.app.DialogFragment;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentActivity;

import android.os.Environment;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.Looper;
import android.os.Message;
import android.os.SystemClock;
import android.util.Log;
import android.util.Range;
import android.util.Rational;
import android.util.Size;
import android.util.SparseIntArray;
import android.view.LayoutInflater;
import android.view.OrientationEventListener;
import android.view.Surface;
import android.view.TextureView;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.Toast;

import com.xypower.mppreview.bean.Contants;
import com.xypower.mppreview.widget.ErrorDialog;

import java.io.File;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;
import java.util.concurrent.Semaphore;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;

public class Camera2RawFragment extends Fragment {

    static {
        loadLibrary("mppreview");
    }

    private static final SparseIntArray ORIENTATIONS = new SparseIntArray();

    static {
        ORIENTATIONS.append(Surface.ROTATION_0, 0);
        ORIENTATIONS.append(Surface.ROTATION_90, 90);
        ORIENTATIONS.append(Surface.ROTATION_180, 180);
        ORIENTATIONS.append(Surface.ROTATION_270, 270);
    }

    /**
     * Request code for camera permissions.
     */
    private static final int REQUEST_CAMERA_PERMISSIONS = 1;

    /**
     * Permissions required to take a picture.
     */
    private static final String[] CAMERA_PERMISSIONS = {Manifest.permission.CAMERA, Manifest.permission.READ_EXTERNAL_STORAGE, Manifest.permission.WRITE_EXTERNAL_STORAGE,};

    /**
     * Timeout for the pre-capture sequence.
     */
    private static final long PRECAPTURE_TIMEOUT_MS = 1000;

    /**
     * Tolerance when comparing aspect ratios.
     */
    private static final double ASPECT_RATIO_TOLERANCE = 0.005;

    /**
     * Max preview width that is guaranteed by Camera2 API
     */
    private static final int MAX_PREVIEW_WIDTH = 1920;

    private static final int MAX_PREVIEW_HEIGHT = 1080;

    private static final String TAG = "Camera2RawFragment";

    private static final int STATE_CLOSED = 0;

    private static final int STATE_OPENED = 1;

    private static final int STATE_PREVIEW = 2;

    private static final int STATE_WAITING_FOR_3A_CONVERGENCE = 3;

    private OrientationEventListener mOrientationListener;


    public static native boolean makeHdr(long exposureTime1, String path1, long exposureTime2, String path2, String outputPath);

    public static native boolean makeHdr2(long exposureTime1, String path1, long exposureTime2, String path2, long exposureTime3, String path3, String outputPath);


    private int mExposureComp = MainActivity.ExposureComp;

    private Long exposetime;
    private Integer sensitivity;

    public boolean isHandTakePic = true;

    private double pic1 = 0;

    /**
     * {@link TextureView.SurfaceTextureListener} handles several lifecycle events of a
     * {@link TextureView}.
     */
    private final TextureView.SurfaceTextureListener mSurfaceTextureListener = new TextureView.SurfaceTextureListener() {

        @Override
        public void onSurfaceTextureAvailable(SurfaceTexture texture, int width, int height) {
            configureTransform(width, height);
        }

        @Override
        public void onSurfaceTextureSizeChanged(SurfaceTexture texture, int width, int height) {
            configureTransform(width, height);
        }

        @Override
        public boolean onSurfaceTextureDestroyed(SurfaceTexture texture) {
            synchronized (mCameraStateLock) {
                mPreviewSize = null;
            }
            return true;
        }

        @Override
        public void onSurfaceTextureUpdated(SurfaceTexture texture) {
        }

    };

    /**
     * An {@link AutoFitTextureView} for camera preview.
     */
    private AutoFitTextureView mTextureView;

    /**
     * An additional thread for running tasks that shouldn't block the UI.  This is used for all
     * callbacks from the {@link CameraDevice} and {@link CameraCaptureSession}s.
     */
    private HandlerThread mBackgroundThread;

    /**
     * A counter for tracking corresponding {@link CaptureRequest}s and {@link CaptureResult}s
     * across the {@link CameraCaptureSession} capture callbacks.
     */
    private final AtomicInteger mRequestCounter = new AtomicInteger();

    /**
     * A {@link Semaphore} to prevent the app from exiting before closing the camera.
     */
    private final Semaphore mCameraOpenCloseLock = new Semaphore(1);

    /**
     * A lock protecting camera state.
     */
    private final Object mCameraStateLock = new Object();

    // *********************************************************************************************
    // State protected by mCameraStateLock.
    //
    // The following state is used across both the UI and background threads.  Methods with "Locked"
    // in the name expect mCameraStateLock to be held while calling.

    /**
     * ID of the current {@link CameraDevice}.
     */
    private String mCameraId;

    /**
     * A {@link CameraCaptureSession } for camera preview.
     */
    private CameraCaptureSession mCaptureSession;

    /**
     * A reference to the open {@link CameraDevice}.
     */
    private CameraDevice mCameraDevice;

    /**
     * The {@link Size} of camera preview.
     */
    private Size mPreviewSize;

    /**
     * The {@link CameraCharacteristics} for the currently configured camera device.
     */
    private CameraCharacteristics mCharacteristics;

    /**
     * A {@link Handler} for running tasks in the background.
     */
    private Handler mBackgroundHandler;

    /**
     * A reference counted holder wrapping the {@link ImageReader} that handles JPEG image
     * captures. This is used to allow us to clean up the {@link ImageReader} when all background
     * tasks using its {@link Image}s have completed.
     */
//    private RefCountedAutoCloseable<ImageReader> mJpegImageReader;

    /**
     * A reference counted holder wrapping the {@link ImageReader} that handles RAW image captures.
     * This is used to allow us to clean up the {@link ImageReader} when all background tasks using
     * its {@link Image}s have completed.
     */
    private RefCountedAutoCloseable<ImageReader> mRawImageReader;

    /**
     * Whether or not the currently configured camera device is fixed-focus.
     */
    private boolean mNoAFRun = false;

    /**
     * Number of pending user requests to capture a photo.
     */
    private int mPendingUserCaptures = 0;

    /**
     * Request ID to {@link ImageSaverBuilder} mapping for in-progress JPEG captures.
     */
    private final TreeMap<Integer, ImageSaverBuilder> mJpegResultQueue = new TreeMap<>();

    /**
     * Request ID to {@link ImageSaverBuilder} mapping for in-progress RAW captures.
     */
    private final TreeMap<Integer, ImageSaverBuilder> mRawResultQueue = new TreeMap<>();

    /**
     * {@link CaptureRequest.Builder} for the camera preview
     */
    private CaptureRequest.Builder mPreviewRequestBuilder;

    /**
     * The state of the camera device.
     *
     * @see #mPreCaptureCallback
     */
    private int mState = STATE_CLOSED;

    /**
     * Timer to use with pre-capture sequence to ensure a timely capture if 3A convergence is
     * taking too long.
     */
    private long mCaptureTimer;

    //**********************************************************************************************

    /**
     * {@link CameraDevice.StateCallback} is called when the currently active {@link CameraDevice}
     * changes its state.
     */
    private final CameraDevice.StateCallback mStateCallback = new CameraDevice.StateCallback() {

        @Override
        public void onOpened(CameraDevice cameraDevice) {
            // This method is called when the camera is opened.  We start camera preview here if
            // the TextureView displaying this has been set up.
            synchronized (mCameraStateLock) {
                mState = STATE_OPENED;
                mCameraOpenCloseLock.release();
                mCameraDevice = cameraDevice;

                // Start the preview session if the TextureView has been set up already.
                if (mPreviewSize != null && mTextureView.isAvailable()) {
                    createCameraPreviewSessionLocked();
                }
            }
        }

        @Override
        public void onDisconnected(CameraDevice cameraDevice) {
            synchronized (mCameraStateLock) {
                mState = STATE_CLOSED;
                mCameraOpenCloseLock.release();
                cameraDevice.close();
                mCameraDevice = null;
            }
        }

        @Override
        public void onError(CameraDevice cameraDevice, int error) {
            Log.e(TAG, "Received camera device error: " + error);
            synchronized (mCameraStateLock) {
                mState = STATE_CLOSED;
                mCameraOpenCloseLock.release();
                cameraDevice.close();
                mCameraDevice = null;
            }
            Activity activity = getActivity();
            if (null != activity) {
                activity.finish();
            }
        }

    };

    /**
     * This a callback object for the {@link ImageReader}. "onImageAvailable" will be called when a
     * JPEG image is ready to be saved.
     */
    private final ImageReader.OnImageAvailableListener mOnJpegImageAvailableListener = new ImageReader.OnImageAvailableListener() {

        @Override
        public void onImageAvailable(ImageReader reader) {
//            dequeueAndSaveImage(mJpegResultQueue, mJpegImageReader);
        }

    };

    /**
     * This a callback object for the {@link ImageReader}. "onImageAvailable" will be called when a
     * RAW image is ready to be saved.
     */
    private final ImageReader.OnImageAvailableListener mOnRawImageAvailableListener = new ImageReader.OnImageAvailableListener() {
        @Override
        public void onImageAvailable(ImageReader reader) {
            dequeueAndSaveImage(mRawResultQueue, mRawImageReader);
        }
    };


    /**
     * /**
     * A {@link CameraCaptureSession.CaptureCallback} that handles events for the preview and
     * pre-capture sequence.
     */
    private CameraCaptureSession.CaptureCallback mPreCaptureCallback = new CameraCaptureSession.CaptureCallback() {

        private void process(CaptureResult result) {
            synchronized (mCameraStateLock) {
                switch (mState) {
                    case STATE_PREVIEW: {
                        // We have nothing to do when the camera preview is running normally.
                        break;
                    }
                    case STATE_WAITING_FOR_3A_CONVERGENCE: {
                        boolean readyToCapture = true;
                        if (!mNoAFRun) {
                            Integer afState = result.get(CaptureResult.CONTROL_AF_STATE);
                            //获取自动曝光时间
                            exposetime = result.get(CaptureResult.SENSOR_EXPOSURE_TIME);
                            //获取自动ISO
                            sensitivity = result.get(CaptureResult.SENSOR_SENSITIVITY);
                            if (afState == null) {
                                break;
                            }
                            readyToCapture = (afState == CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED || afState == CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED);
                        }

                        if (!isLegacyLocked()) {
                            Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE);
                            Integer awbState = result.get(CaptureResult.CONTROL_AWB_STATE);
                            if (aeState == null || awbState == null) {
                                break;
                            }

                            readyToCapture = readyToCapture && aeState == CaptureResult.CONTROL_AE_STATE_CONVERGED && awbState == CaptureResult.CONTROL_AWB_STATE_CONVERGED;
                        }

                        if (!readyToCapture && hitTimeoutLocked()) {
                            Log.w(TAG, "Timed out waiting for pre-capture sequence to complete.");
                            readyToCapture = true;
                        }

                        if (readyToCapture && mPendingUserCaptures > 0) {
                            while (mPendingUserCaptures > 0) {
                                captureStillPictureLocked(exposetime, sensitivity);
                                mPendingUserCaptures--;
                            }
                            mState = STATE_PREVIEW;
                        }
                    }
                }
            }
        }

        @Override
        public void onCaptureProgressed(CameraCaptureSession session, CaptureRequest request, CaptureResult partialResult) {
            process(partialResult);
        }

        @Override
        public void onCaptureCompleted(CameraCaptureSession session, CaptureRequest request, TotalCaptureResult result) {
            process(result);
        }

    };

    private final CameraCaptureSession.CaptureCallback mCaptureCallback = new CameraCaptureSession.CaptureCallback() {
        @Override
        public void onCaptureStarted(CameraCaptureSession session, CaptureRequest request, long timestamp, long frameNumber) {
            synchronized (mCameraStateLock) {
                String currentDateTime = generateTimestamp();
                File directory = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM);
                File rawFile = new File(directory, "RAW_" + currentDateTime + ".dng");
//                File jpegFile = new File(directory, "JPEG_" + currentDateTime + ".png");

//                ImageSaverBuilder jpegBuilder;
                ImageSaverBuilder rawBuilder;
                int requestId = (int) request.getTag();
//                jpegBuilder = mJpegResultQueue.get(requestId);
                rawBuilder = mRawResultQueue.get(requestId);

//                if (jpegBuilder != null) jpegBuilder.setFile(jpegFile);
                if (rawBuilder != null) rawBuilder.setFile(rawFile);
            }
        }

        @Override
        public void onCaptureCompleted(CameraCaptureSession session, CaptureRequest request, TotalCaptureResult result) {
            int requestId = (int) request.getTag();
            ImageSaverBuilder jpegBuilder;
            ImageSaverBuilder rawBuilder;
            StringBuilder sb = new StringBuilder();

            synchronized (mCameraStateLock) {
                jpegBuilder = mJpegResultQueue.get(requestId);
                rawBuilder = mRawResultQueue.get(requestId);

//                if (jpegBuilder != null) {
//                    jpegBuilder.setResult(result);
//                    sb.append("Saving JPEG as: ");
//                    sb.append(jpegBuilder.getSaveLocation());
//                }
                if (rawBuilder != null) {
                    rawBuilder.setResult(result);
                    if (rawBuilder != null) sb.append(", ");
                    sb.append("Saving RAW as: ");
                    sb.append(rawBuilder.getSaveLocation());
                }

                handleCompletionLocked(requestId, jpegBuilder, mJpegResultQueue);
                handleCompletionLocked(requestId, rawBuilder, mRawResultQueue);

                finishedCaptureLocked();
            }

            showToast(sb.toString());
        }

        @Override
        public void onCaptureFailed(CameraCaptureSession session, CaptureRequest request, CaptureFailure failure) {
            int requestId = (int) request.getTag();
            synchronized (mCameraStateLock) {
                mJpegResultQueue.remove(requestId);
                mRawResultQueue.remove(requestId);
                finishedCaptureLocked();
            }
            showToast("Capture failed!");
        }

    };

    private final Handler mMessageHandler = new Handler(Looper.getMainLooper()) {
        @Override
        public void handleMessage(Message msg) {
            Activity activity = getActivity();
            if (activity != null) {
                Toast.makeText(activity, (String) msg.obj, Toast.LENGTH_SHORT).show();
            }
        }
    };


    public static Camera2RawFragment newInstance() {
        return new Camera2RawFragment();
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_camera2_raw, container, false);
    }

    @Override
    public void onViewCreated(final View view, Bundle savedInstanceState) {
        mTextureView = (AutoFitTextureView) view.findViewById(R.id.texture);
        Bundle arguments = getArguments();
        if (arguments != null) {
            pic1 = arguments.getInt(Contants.HDRNUM);
        }
        mOrientationListener = new OrientationEventListener(getActivity(), SensorManager.SENSOR_DELAY_NORMAL) {
            @Override
            public void onOrientationChanged(int orientation) {
                if (mTextureView != null && mTextureView.isAvailable()) {
                    configureTransform(mTextureView.getWidth(), mTextureView.getHeight());
                }
            }
        };
        Button takepic = view.findViewById(R.id.takepic);
        takepic.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                isHandTakePic = true;
                takePicture();
            }
        });
    }

    @Override
    public void onResume() {
        super.onResume();
        startBackgroundThread();
        openCamera();
        if (mTextureView.isAvailable()) {
            configureTransform(mTextureView.getWidth(), mTextureView.getHeight());
        } else {
            mTextureView.setSurfaceTextureListener(mSurfaceTextureListener);
        }
        if (mOrientationListener != null && mOrientationListener.canDetectOrientation()) {
            mOrientationListener.enable();
        }
    }

    @Override
    public void onPause() {
        if (mOrientationListener != null) {
            mOrientationListener.disable();
        }
        closeCamera();
        stopBackgroundThread();
        super.onPause();
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        if (requestCode == REQUEST_CAMERA_PERMISSIONS) {
            for (int result : grantResults) {
                if (result != PackageManager.PERMISSION_GRANTED) {
                    showMissingPermissionError();
                    return;
                }
            }
        } else {
            super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        }
    }

    private void restartFragment() {
        final FragmentActivity activity = getActivity();

        mBackgroundHandler.postDelayed(new Runnable() {
            @Override
            public void run() {
                activity.getSupportFragmentManager().beginTransaction().replace(R.id.container, Camera2RawFragment.newInstance()).commit();
            }
        }, 100);
    }

    public void doFocus() {

        int previewWidth = mTextureView.getWidth();
        int previewHeight = mTextureView.getHeight();
        RectF previewRect = new RectF(0, 0, previewWidth, previewHeight);

        CoordinateTransformer cf = new CoordinateTransformer(mCharacteristics, previewRect);

        RectF rect = cf.toCameraSpace(previewRect);

        MeteringRectangle mr = new MeteringRectangle(new Rect((int) rect.left, (int) rect.top, (int) rect.right, (int) rect.bottom), 1000);
        startControlAFRequest(mr, mPreCaptureCallback);
    }

    public void startControlAFRequest(MeteringRectangle rect, CameraCaptureSession.CaptureCallback captureCallback) {

        MeteringRectangle[] rectangle = new MeteringRectangle[]{rect};
        // Focus Mode AUTO
        // mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE,CaptureRequest.CONTROL_AF_MODE_AUTO);
        //AE
        mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_REGIONS, rectangle);
        //AF 此处AF和AE用的同一个rect, 实际AE矩形面积比AF稍大, 这样测光效果更好
        mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_REGIONS, rectangle);
        try {
            // AE/AF区域设置通过setRepeatingRequest不断发请求
            mCaptureSession.setRepeatingRequest(mPreviewRequestBuilder.build(), captureCallback, mBackgroundHandler);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
        //触发对焦
        mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, CaptureRequest.CONTROL_AF_TRIGGER_START);
        try {
            //触发对焦通过capture发送请求, 因为用户点击屏幕后只需触发一次对焦
            mCaptureSession.capture(mPreviewRequestBuilder.build(), captureCallback, mBackgroundHandler);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }

    /**
     * Sets up state related to camera that is needed before opening a {@link CameraDevice}.
     */
    private boolean setUpCameraOutputs() {
        Activity activity = getActivity();
        assert activity != null;
        CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE);
        if (manager == null) {
            ErrorDialog.buildErrorDialog("This device doesn't support Camera2 API.").show(getFragmentManager(), "dialog");
            return false;
        }
        try {
            // Find a CameraDevice that supports RAW captures, and configure state.
            for (String cameraId : manager.getCameraIdList()) {
                CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraId);

                // We only use a camera that supports RAW in this sample.
                if (!contains(characteristics.get(CameraCharacteristics.REQUEST_AVAILABLE_CAPABILITIES), CameraCharacteristics.REQUEST_AVAILABLE_CAPABILITIES_RAW)) {
                    continue;
                }
                StreamConfigurationMap map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);
                // For still image captures, we use the largest available size.
                Size largestJpeg = Collections.max(Arrays.asList(map.getOutputSizes(ImageFormat.JPEG)), new CompareSizesByArea());

                Size largestRaw = Collections.max(Arrays.asList(map.getOutputSizes(ImageFormat.RAW_SENSOR)), new CompareSizesByArea());

                synchronized (mCameraStateLock) {
                    // Set up ImageReaders for JPEG and RAW outputs.  Place these in a reference
                    // counted wrapper to ensure they are only closed when all background tasks
                    // using them are finished.
//                    if (mJpegImageReader == null || mJpegImageReader.getAndRetain() == null) {
//                        mJpegImageReader = new RefCountedAutoCloseable<>(ImageReader.newInstance(largestJpeg.getWidth(), largestJpeg.getHeight(), ImageFormat.JPEG, /*maxImages*/5));
//                    }
//                    mJpegImageReader.get().setOnImageAvailableListener(mOnJpegImageAvailableListener, mBackgroundHandler);

                    if (mRawImageReader == null || mRawImageReader.getAndRetain() == null) {
                        mRawImageReader = new RefCountedAutoCloseable<>(ImageReader.newInstance(largestRaw.getWidth(), largestRaw.getHeight(), ImageFormat.RAW_SENSOR, /*maxImages*/ 5));
                    }
                    mRawImageReader.get().setOnImageAvailableListener(mOnRawImageAvailableListener, mBackgroundHandler);
                    mCharacteristics = characteristics;
                    mCameraId = cameraId;
                }
                return true;
            }
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }

        // If we found no suitable cameras for capturing RAW, warn the user.
        ErrorDialog.buildErrorDialog("This device doesn't support capturing RAW photos").show(getFragmentManager(), "dialog");
        return false;
    }

    /**
     * Opens the camera specified by {@link #mCameraId}.
     */
    @SuppressWarnings("MissingPermission")
    private void openCamera() {
        if (!setUpCameraOutputs()) {
            return;
        }
        if (!hasAllPermissionsGranted()) {
            requestCameraPermissions();
            return;
        }
        CameraManager manager = (CameraManager) getActivity().getSystemService(Context.CAMERA_SERVICE);
        try {
            if (!mCameraOpenCloseLock.tryAcquire(2500, TimeUnit.MILLISECONDS)) {
                throw new RuntimeException("Time out waiting to lock camera opening.");
            }
            Handler backgroundHandler;
            synchronized (mCameraStateLock) {
                backgroundHandler = mBackgroundHandler;
            }
            manager.openCamera(mCameraId, mStateCallback, backgroundHandler);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        } catch (InterruptedException e) {
            throw new RuntimeException("Interrupted while trying to lock camera opening.", e);
        }
    }

    /**
     * Requests permissions necessary to use camera and save pictures.
     */
    private void requestCameraPermissions() {

    }

    /**
     * Tells whether all the necessary permissions are granted to this app.
     *
     * @return True if all the required permissions are granted.
     */
    private boolean hasAllPermissionsGranted() {
        return true;
    }

    /**
     * Gets whether you should show UI with rationale for requesting the permissions.
     *
     * @return True if the UI should be shown.
     */
    private boolean shouldShowRationale() {
        return false;
    }

    /**
     * Shows that this app really needs the permission and finishes the app.
     */
    private void showMissingPermissionError() {
        Activity activity = getActivity();
        if (activity != null) {
            Toast.makeText(activity, R.string.request_permission, Toast.LENGTH_SHORT).show();
            activity.finish();
        }
    }

    /**
     * Closes the current {@link CameraDevice}.
     */
    private void closeCamera() {
        try {
            mCameraOpenCloseLock.acquire();
            synchronized (mCameraStateLock) {

                // Reset state and clean up resources used by the camera.
                // Note: After calling this, the ImageReaders will be closed after any background
                // tasks saving Images from these readers have been completed.
                mPendingUserCaptures = 0;
                mState = STATE_CLOSED;
                if (null != mCaptureSession) {
                    mCaptureSession.close();
                    mCaptureSession = null;
                }
                if (null != mCameraDevice) {
                    mCameraDevice.close();
                    mCameraDevice = null;
                }
//                if (null != mJpegImageReader) {
//                    mJpegImageReader.close();
//                    mJpegImageReader = null;
//                }
                if (null != mRawImageReader) {
                    mRawImageReader.close();
                    mRawImageReader = null;
                }
            }
        } catch (InterruptedException e) {
            throw new RuntimeException("Interrupted while trying to lock camera closing.", e);
        } finally {
            mCameraOpenCloseLock.release();
        }
    }

    /**
     * Starts a background thread and its {@link Handler}.
     */
    private void startBackgroundThread() {
        mBackgroundThread = new HandlerThread("CameraBackground");
        mBackgroundThread.start();
        synchronized (mCameraStateLock) {
            mBackgroundHandler = new Handler(mBackgroundThread.getLooper());
        }
    }

    /**
     * Stops the background thread and its {@link Handler}.
     */
    private void stopBackgroundThread() {
        mBackgroundThread.quitSafely();
        try {
            mBackgroundThread.join();
            mBackgroundThread = null;
            synchronized (mCameraStateLock) {
                mBackgroundHandler = null;
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    /**
     * Creates a new {@link CameraCaptureSession} for camera preview.
     * <p/>
     * Call this only with {@link #mCameraStateLock} held.
     */
    private void createCameraPreviewSessionLocked() {
        try {
            SurfaceTexture texture = mTextureView.getSurfaceTexture();
            // We configure the size of default buffer to be the size of camera preview we want.
            texture.setDefaultBufferSize(mPreviewSize.getWidth(), mPreviewSize.getHeight());

            // This is the output Surface we need to start preview.
            Surface surface = new Surface(texture);

            // We set up a CaptureRequest.Builder with the output Surface.
            mPreviewRequestBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW);
            mPreviewRequestBuilder.addTarget(surface);

            // Here, we create a CameraCaptureSession for camera preview.
            mCameraDevice.createCaptureSession(Arrays.asList(surface, mRawImageReader.get().getSurface()), new CameraCaptureSession.StateCallback() {
                @Override
                public void onConfigured(CameraCaptureSession cameraCaptureSession) {
                    synchronized (mCameraStateLock) {
                        // The camera is already closed
                        if (null == mCameraDevice) {
                            return;
                        }

                        try {
                            setup3AControlsLocked(mPreviewRequestBuilder);

                            if (mExposureComp != 0) {
                                mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_EXPOSURE_COMPENSATION, mExposureComp);
                            }
                            // Finally, we start displaying the camera preview.
                            cameraCaptureSession.setRepeatingRequest(mPreviewRequestBuilder.build(), mPreCaptureCallback, mBackgroundHandler);
                            mState = STATE_PREVIEW;
                        } catch (CameraAccessException | IllegalStateException e) {
                            e.printStackTrace();
                            return;
                        }
                        // When the session is ready, we start displaying the preview.
                        mCaptureSession = cameraCaptureSession;
                    }
                }

                @Override
                public void onConfigureFailed(CameraCaptureSession cameraCaptureSession) {
                    showToast("Failed to configure camera.");
                }
            }, mBackgroundHandler);
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }

    /**
     * Configure the given {@link CaptureRequest.Builder} to use auto-focus, auto-exposure, and
     * auto-white-balance controls if available.
     * <p/>
     * Call this only with {@link #mCameraStateLock} held.
     *
     * @param builder the builder to configure.
     */
    private void setup3AControlsLocked(CaptureRequest.Builder builder) {


        // parameters.setPreviewFpsRange(10,30);
        // parameters.setPreviewFrameRate(10);

        Range<Integer>[] fpsRanges = mCharacteristics.get(CameraCharacteristics.CONTROL_AE_AVAILABLE_TARGET_FPS_RANGES);
        Range<Integer> fpsRange = new Range<>(5, 30);
        builder.set(CaptureRequest.CONTROL_AE_TARGET_FPS_RANGE, fpsRange);

        // Enable auto-magical 3A run by camera device
        builder.set(CaptureRequest.CONTROL_MODE, CaptureRequest.CONTROL_MODE_AUTO);

        Float minFocusDist = mCharacteristics.get(CameraCharacteristics.LENS_INFO_MINIMUM_FOCUS_DISTANCE);

        // If MINIMUM_FOCUS_DISTANCE is 0, lens is fixed-focus and we need to skip the AF run.
        mNoAFRun = (minFocusDist == null || minFocusDist == 0);

        if (!mNoAFRun) {
            // If there is a "continuous picture" mode available, use it, otherwise default to AUTO.
            if (contains(mCharacteristics.get(CameraCharacteristics.CONTROL_AF_AVAILABLE_MODES), CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE)) {
                builder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE);
            } else {
                builder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_AUTO);
            }

            // MeteringRectangle mr = new MeteringRectangle(rect, 1000);
            // builder.set(CaptureRequest.CONTROL_AF_REGIONS, new MeteringRectangle[] {mr});
            // builder.set(CaptureRequest.CONTROL_AE_REGIONS, new MeteringRectangle[] {mr});

            // builder.set(CaptureRequest.CONTROL_AF_REGIONS, arrayOf(MeteringRectangle(rect, 1000)))

            // set(CaptureRequest.CONTROL_AE_REGIONS, arrayOf(MeteringRectangle(rect, 1000)))
        }

        // If there is an auto-magical flash control mode available, use it, otherwise default to
        // the "on" mode, which is guaranteed to always be available.
        if (contains(mCharacteristics.get(CameraCharacteristics.CONTROL_AE_AVAILABLE_MODES), CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH)) {

            builder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH);
        } else {
            builder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON);
        }

        // If there is an auto-magical white balance control mode available, use it.
        if (contains(mCharacteristics.get(CameraCharacteristics.CONTROL_AWB_AVAILABLE_MODES), CaptureRequest.CONTROL_AWB_MODE_DAYLIGHT)) {
            // Allow AWB to run auto-magically if this device supports this
            builder.set(CaptureRequest.CONTROL_AWB_MODE, CaptureRequest.CONTROL_AWB_MODE_DAYLIGHT);
        } else if (contains(mCharacteristics.get(CameraCharacteristics.CONTROL_AWB_AVAILABLE_MODES), CaptureRequest.CONTROL_AWB_MODE_AUTO)) {
//             Allow AWB to run auto-magically if this device supports this
            builder.set(CaptureRequest.CONTROL_AWB_MODE, CaptureRequest.CONTROL_AWB_MODE_AUTO);
        }
    }

    private void configureTransform(int viewWidth, int viewHeight) {
        Activity activity = getActivity();
        synchronized (mCameraStateLock) {
            if (null == mTextureView || null == activity) {
                return;
            }

            StreamConfigurationMap map = null;

            if (map == null) {
                try {
                    map = mCharacteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP);
                } catch (Exception ex) {
                    ex.printStackTrace();
                }
            }
            // For still image captures, we always use the largest available size.
            Size largestJpeg = Collections.max(Arrays.asList(map.getOutputSizes(ImageFormat.JPEG)), new CompareSizesByArea());

            // Find the rotation of the device relative to the native device orientation.
            int deviceRotation = activity.getWindowManager().getDefaultDisplay().getRotation();
            Point displaySize = new Point();
            activity.getWindowManager().getDefaultDisplay().getSize(displaySize);

            // Find the rotation of the device relative to the camera sensor's orientation.
            int totalRotation = sensorToDeviceRotation(mCharacteristics, deviceRotation);

            // Swap the view dimensions for calculation as needed if they are rotated relative to
            // the sensor.
            boolean swappedDimensions = totalRotation == 90 || totalRotation == 270;
            int rotatedViewWidth = viewWidth;
            int rotatedViewHeight = viewHeight;
            int maxPreviewWidth = displaySize.x;
            int maxPreviewHeight = displaySize.y;

            if (swappedDimensions) {
                rotatedViewWidth = viewHeight;
                rotatedViewHeight = viewWidth;
                maxPreviewWidth = displaySize.y;
                maxPreviewHeight = displaySize.x;
            }

            // Preview should not be larger than display size and 1080p.
            if (maxPreviewWidth > MAX_PREVIEW_WIDTH) {
                maxPreviewWidth = MAX_PREVIEW_WIDTH;
            }

            if (maxPreviewHeight > MAX_PREVIEW_HEIGHT) {
                maxPreviewHeight = MAX_PREVIEW_HEIGHT;
            }

            // Find the best preview size for these view dimensions and configured JPEG size.
            Size previewSize = chooseOptimalSize(map.getOutputSizes(SurfaceTexture.class), rotatedViewWidth, rotatedViewHeight, maxPreviewWidth, maxPreviewHeight, largestJpeg);
//            Size previewSize = new Size(3840, 2160);

            if (swappedDimensions) {
                mTextureView.setAspectRatio(previewSize.getHeight(), previewSize.getWidth());
            } else {
                mTextureView.setAspectRatio(previewSize.getWidth(), previewSize.getHeight());
            }

            // Find rotation of device in degrees (reverse device orientation for front-facing
            // cameras).
            int rotation = (mCharacteristics.get(CameraCharacteristics.LENS_FACING) == CameraCharacteristics.LENS_FACING_FRONT) ? (360 + ORIENTATIONS.get(deviceRotation)) % 360 : (360 - ORIENTATIONS.get(deviceRotation)) % 360;

            Matrix matrix = new Matrix();
            RectF viewRect = new RectF(0, 0, viewWidth, viewHeight);
            RectF bufferRect = new RectF(0, 0, previewSize.getHeight(), previewSize.getWidth());
            float centerX = viewRect.centerX();
            float centerY = viewRect.centerY();

//            if (Surface.ROTATION_90 == deviceRotation || Surface.ROTATION_270 == deviceRotation) {
//                bufferRect.offset(centerX - bufferRect.centerX(), centerY - bufferRect.centerY());
//                matrix.setRectToRect(viewRect, bufferRect, Matrix.ScaleToFit.FILL);
//                float scale = Math.max((float) viewHeight / previewSize.getHeight(), (float) viewWidth / previewSize.getWidth());
//                matrix.postScale(scale, scale, centerX, centerY);
//
//            }

            if (Surface.ROTATION_90 == deviceRotation || Surface.ROTATION_270 == deviceRotation) {
                if (rotation == 0) {
                    matrix.postScale(1, 1);
                } else if (rotation == 90) {
                    bufferRect.offset(centerX - bufferRect.centerX(), centerY - bufferRect.centerY());
                    matrix.setRectToRect(viewRect, bufferRect, Matrix.ScaleToFit.FILL);
                    float scaleh = (float) viewHeight / previewSize.getHeight();
                    float scalew = (float) viewWidth / previewSize.getWidth();
                    matrix.postScale(scalew, scaleh, centerX, centerY);
                } else if (rotation == 180) {
                    matrix.postScale(1, 1);
                } else if (rotation == 270) {
                    bufferRect.offset(centerX - bufferRect.centerX(), centerY - bufferRect.centerY());
                    matrix.setRectToRect(viewRect, bufferRect, Matrix.ScaleToFit.FILL);
                    float scaleh = (float) viewHeight / previewSize.getHeight();
                    float scalew = (float) viewWidth / previewSize.getWidth();
                    matrix.postScale(scaleh, scalew, centerX, centerY);
                }
            }
            matrix.postRotate(rotation, centerX, centerY);

            mTextureView.setTransform(matrix);

            // Start or restart the active capture session if the preview was initialized or
            // if its aspect ratio changed significantly.
            if (mPreviewSize == null || !checkAspectsEqual(previewSize, mPreviewSize)) {
                mPreviewSize = previewSize;
                if (mState != STATE_CLOSED) {
                    createCameraPreviewSessionLocked();
                }
            }
        }
    }

    public void takePicture() {
        synchronized (mCameraStateLock) {
            mPendingUserCaptures++;
            if (mState != STATE_PREVIEW) {
                return;
            }
            try {
                if (!isLegacyLocked()) {
                    mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER, CameraMetadata.CONTROL_AE_PRECAPTURE_TRIGGER_START);
                }
                if (!mNoAFRun) {
                    mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, CameraMetadata.CONTROL_AF_TRIGGER_START);
                }
                mState = STATE_WAITING_FOR_3A_CONVERGENCE;
                startTimerLocked();
                mCaptureSession.capture(mPreviewRequestBuilder.build(), mPreCaptureCallback, mBackgroundHandler);
            } catch (CameraAccessException e) {
                e.printStackTrace();
            }
        }
    }

    private void captureStillPictureLocked(long exposureTime, int sensitivity) {
        try {
            final Activity activity = getActivity();
            if (null == activity || null == mCameraDevice) {
                return;
            }
            // This is the CaptureRequest.Builder that we use to take a picture.
            final CaptureRequest.Builder captureBuilder = mCameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_STILL_CAPTURE);

//            captureBuilder.addTarget(mJpegImageReader.get().getSurface());
            captureBuilder.addTarget(mRawImageReader.get().getSurface());

            // Use the same AE and AF modes as the preview.
            setup3AControlsLocked(captureBuilder);

            if (mExposureComp != 0) {
                mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_EXPOSURE_COMPENSATION, mExposureComp);
            }

            // Set orientation.
            int rotation = activity.getWindowManager().getDefaultDisplay().getRotation();
            captureBuilder.set(CaptureRequest.JPEG_ORIENTATION, sensorToDeviceRotation(mCharacteristics, rotation));

            Range<Integer> range = mCharacteristics.get(CameraCharacteristics.CONTROL_AE_COMPENSATION_RANGE);
            Rational rational = mCharacteristics.get(CameraCharacteristics.CONTROL_AE_COMPENSATION_STEP);
            double step = rational.doubleValue();

            // mCharacteristics.get(CameraMetadata.CONTROL_AE_COMPENSATION_STEP)
            List<CaptureRequest> requests = new ArrayList<>();
            double v = 0;
            for (int idx = 0; idx < 2; idx++) {
                // Set request tag to easily track results in callbacks.
                captureBuilder.setTag(mRequestCounter.getAndIncrement());

                if (idx == 0) {
//                    captureBuilder.set(CaptureRequest.CONTROL_AE_EXPOSURE_COMPENSATION, new Integer(4));
                    // 设置曝光时间，例如设置为1000微秒
//        long exposureTime = 1000  000000L; // 1000微秒
                    if (isHandTakePic) {

                        captureBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_OFF);
                        if (exposureTime > 0) {
                            v = exposureTime * pic1;
                            captureBuilder.set(CaptureRequest.SENSOR_EXPOSURE_TIME, (long) v);
                        }
                        if (sensitivity > 0) {
                            captureBuilder.set(CaptureRequest.SENSOR_SENSITIVITY, sensitivity);
                        }
                    }
                }

                if (idx == 1) {
//                    captureBuilder.set(CaptureRequest.CONTROL_AE_EXPOSURE_COMPENSATION, new Integer(4));
                    // 设置曝光时间，例如设置为1000微秒
//        long exposureTime = 1000  000000L; // 1000微秒
                    if (isHandTakePic) {
                        captureBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_OFF);
                        if (exposureTime > 0) {
                            if (pic1 <= 0) {
                                v = exposureTime * 7;
                                captureBuilder.set(CaptureRequest.SENSOR_EXPOSURE_TIME, (long) v);
                            } else {
                                v = exposureTime * pic1;
                                captureBuilder.set(CaptureRequest.SENSOR_EXPOSURE_TIME, (long) v);
                            }
                        }
                        if (sensitivity > 0) {
                            captureBuilder.set(CaptureRequest.SENSOR_SENSITIVITY, 100);
                        }
                    }
                }
                CaptureRequest request = captureBuilder.build();
//                ImageSaverBuilder jpegBuilder = new ImageSaverBuilder(activity).setCharacteristics(mCharacteristics);
                ImageSaverBuilder rawBuilder = new ImageSaverBuilder(activity).setCharacteristics(mCharacteristics);//保存拍照参数
                rawBuilder.setExposetime((long) v);//保存曝光时间
//                mJpegResultQueue.put((int) request.getTag(), jpegBuilder);
                mRawResultQueue.put((int) request.getTag(), rawBuilder);
                requests.add(request);
            }
            mCaptureSession.captureBurst(requests, mCaptureCallback, mBackgroundHandler);
//
//            // Set request tag to easily track results in callbacks.
//            captureBuilder.setTag(mRequestCounter.getAndIncrement());
//
//            CaptureRequest request = captureBuilder.build();
//
//            // Create an ImageSaverBuilder in which to collect results, and add it to the queue
//            // of active requests.
//            ImageSaver.ImageSaverBuilder jpegBuilder = new ImageSaver.ImageSaverBuilder(activity).setCharacteristics(mCharacteristics);
//            ImageSaver.ImageSaverBuilder rawBuilder = new ImageSaver.ImageSaverBuilder(activity).setCharacteristics(mCharacteristics);
//
//            mJpegResultQueue.put((int) request.getTag(), jpegBuilder);
//            mRawResultQueue.put((int) request.getTag(), rawBuilder);
//
//            mCaptureSession.capture(request, mCaptureCallback, mBackgroundHandler);


        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }

    private void finishedCaptureLocked() {
        try {
            if (!mNoAFRun) {
                mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, CameraMetadata.CONTROL_AF_TRIGGER_CANCEL);
                mCaptureSession.capture(mPreviewRequestBuilder.build(), mPreCaptureCallback, mBackgroundHandler);
                mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, CameraMetadata.CONTROL_AF_TRIGGER_IDLE);
            }
        } catch (CameraAccessException e) {
            e.printStackTrace();
        }
    }

    private void dequeueAndSaveImage(TreeMap<Integer, ImageSaverBuilder> pendingQueue, RefCountedAutoCloseable<ImageReader> reader) {
        synchronized (mCameraStateLock) {
            Map.Entry<Integer, ImageSaverBuilder> entry = null;
            if (pendingQueue != null) {
                for (Map.Entry<Integer, ImageSaverBuilder> item : pendingQueue.entrySet()) {
                    ImageSaverBuilder value = item.getValue();
                    if (value.mImage == null) {
                        entry = item;
                        break;
                    }
                }
            }
            if (entry == null) {
                return;
            }
            ImageSaverBuilder builder = entry.getValue();
            if (reader == null || reader.getAndRetain() == null) {
                Log.e(TAG, "Paused the activity before we could save the image," + " ImageReader already closed.");
                pendingQueue.remove(entry.getKey());
                return;
            }
            Image image;
            try {
                image = reader.get().acquireNextImage();
            } catch (IllegalStateException e) {
                Log.e(TAG, "Too many images queued for saving, dropping image for request: " + entry.getKey());
                pendingQueue.remove(entry.getKey());
                return;
            }
            builder.setRefCountedReader(reader).setImage(image);
            handleCompletionLocked(entry.getKey(), builder, pendingQueue);
        }
    }

    static class CompareSizesByArea implements Comparator<Size> {

        @Override
        public int compare(Size lhs, Size rhs) {
            // We cast here to ensure the multiplications won't overflow
            return Long.signum((long) lhs.getWidth() * lhs.getHeight() - (long) rhs.getWidth() * rhs.getHeight());
        }

    }


    /**
     * A wrapper for an {@link AutoCloseable} object that implements reference counting to allow
     * for resource management.
     */
    public static class RefCountedAutoCloseable<T extends AutoCloseable> implements AutoCloseable {
        private T mObject;
        private long mRefCount = 0;

        /**
         * Wrap the given object.
         *
         * @param object an object to wrap.
         */
        public RefCountedAutoCloseable(T object) {
            if (object == null) throw new NullPointerException();
            mObject = object;
        }

        /**
         * Increment the reference count and return the wrapped object.
         *
         * @return the wrapped object, or null if the object has been released.
         */
        public synchronized T getAndRetain() {
            if (mRefCount < 0) {
                return null;
            }
            mRefCount++;
            return mObject;
        }

        /**
         * Return the wrapped object.
         *
         * @return the wrapped object, or null if the object has been released.
         */
        public synchronized T get() {
            return mObject;
        }

        /**
         * Decrement the reference count and release the wrapped object if there are no other
         * users retaining this object.
         */
        @Override
        public synchronized void close() {
            if (mRefCount >= 0) {
                mRefCount--;
                if (mRefCount < 0) {
                    try {
                        mObject.close();
                    } catch (Exception e) {
                        throw new RuntimeException(e);
                    } finally {
                        mObject = null;
                    }
                }
            }
        }
    }

    /**
     * Given {@code choices} of {@code Size}s supported by a camera, choose the smallest one that
     * is at least as large as the respective texture view size, and that is at most as large as the
     * respective max size, and whose aspect ratio matches with the specified value. If such size
     * doesn't exist, choose the largest one that is at most as large as the respective max size,
     * and whose aspect ratio matches with the specified value.
     *
     * @param choices           The list of sizes that the camera supports for the intended output
     *                          class
     * @param textureViewWidth  The width of the texture view relative to sensor coordinate
     * @param textureViewHeight The height of the texture view relative to sensor coordinate
     * @param maxWidth          The maximum width that can be chosen
     * @param maxHeight         The maximum height that can be chosen
     * @param aspectRatio       The aspect ratio
     * @return The optimal {@code Size}, or an arbitrary one if none were big enough
     */
    private static Size chooseOptimalSize(Size[] choices, int textureViewWidth, int textureViewHeight, int maxWidth, int maxHeight, Size aspectRatio) {
        // Collect the supported resolutions that are at least as big as the preview Surface
        List<Size> bigEnough = new ArrayList<>();
        // Collect the supported resolutions that are smaller than the preview Surface
        List<Size> notBigEnough = new ArrayList<>();
        int w = aspectRatio.getWidth();
        int h = aspectRatio.getHeight();
        for (Size option : choices) {
            if (option.getWidth() <= maxWidth && option.getHeight() <= maxHeight && option.getHeight() == option.getWidth() * h / w) {
                if (option.getWidth() >= textureViewWidth && option.getHeight() >= textureViewHeight) {
                    bigEnough.add(option);
                } else {
                    notBigEnough.add(option);
                }
            }
        }

        // Pick the smallest of those big enough. If there is no one big enough, pick the
        // largest of those not big enough.
        if (bigEnough.size() > 0) {
            return Collections.min(bigEnough, new CompareSizesByArea());
        } else if (notBigEnough.size() > 0) {
            return Collections.max(notBigEnough, new CompareSizesByArea());
        } else {
            Log.e(TAG, "Couldn't find any suitable preview size");
            return choices[0];
        }
    }

    /**
     * Generate a string containing a formatted timestamp with the current date and time.
     *
     * @return a {@link String} representing a time.
     */


    /**
     * Cleanup the given {@link OutputStream}.
     *
     * @param outputStream the stream to close.
     */


    /**
     * Return true if the given array contains the given integer.
     *
     * @param modes array to check.
     * @param mode  integer to get for.
     * @return true if the array contains the given integer, otherwise false.
     */
    private static boolean contains(int[] modes, int mode) {
        if (modes == null) {
            return false;
        }
        for (int i : modes) {
            if (i == mode) {
                return true;
            }
        }
        return false;
    }

    /**
     * Return true if the two given {@link Size}s have the same aspect ratio.
     *
     * @param a first {@link Size} to compare.
     * @param b second {@link Size} to compare.
     * @return true if the sizes have the same aspect ratio, otherwise false.
     */
    private static boolean checkAspectsEqual(Size a, Size b) {
        double aAspect = a.getWidth() / (double) a.getHeight();
        double bAspect = b.getWidth() / (double) b.getHeight();
        return Math.abs(aAspect - bAspect) <= ASPECT_RATIO_TOLERANCE;
    }

    /**
     * Rotation need to transform from the camera sensor orientation to the device's current
     * orientation.
     *
     * @param c                 the {@link CameraCharacteristics} to query for the camera sensor
     *                          orientation.
     * @param deviceOrientation the current device orientation relative to the native device
     *                          orientation.
     * @return the total rotation from the sensor orientation to the current device orientation.
     */
    private static int sensorToDeviceRotation(CameraCharacteristics c, int deviceOrientation) {
        int sensorOrientation = c.get(CameraCharacteristics.SENSOR_ORIENTATION);

        // Get device orientation in degrees
        deviceOrientation = ORIENTATIONS.get(deviceOrientation);

        // Reverse device orientation for front-facing cameras
        if (c.get(CameraCharacteristics.LENS_FACING) == CameraCharacteristics.LENS_FACING_FRONT) {
            deviceOrientation = -deviceOrientation;
        }

        // Calculate desired JPEG orientation relative to camera orientation to make
        // the image upright relative to the device orientation
        return (sensorOrientation - deviceOrientation + 360) % 360;
    }

    /**
     * Shows a {@link Toast} on the UI thread.
     *
     * @param text The message to show.
     */
    private void showToast(String text) {
        // We show a Toast by sending request message to mMessageHandler. This makes sure that the
        // Toast is shown on the UI thread.
        Message message = Message.obtain();
        message.obj = text;
        mMessageHandler.sendMessage(message);
    }

    /**
     * If the given request has been completed, remove it from the queue of active requests and
     * send an {@link ImageSaver} with the results from this request to a background thread to
     * save a file.
     * <p/>
     * Call this only with {@link #mCameraStateLock} held.
     *
     * @param requestId the ID of the {@link CaptureRequest} to handle.
     * @param queue     the queue to remove this request from, if completed.
     */
    private void handleCompletionLocked(int requestId, ImageSaverBuilder builder, TreeMap<Integer, ImageSaverBuilder> queue) {
        if (builder == null) {
            return;
        }
        ImageSaver saver = builder.buildIfComplete();
        System.out.println();
        if (saver != null) {
            queue.remove(requestId);
            AsyncTask.THREAD_POOL_EXECUTOR.execute(saver);
        }
    }

    /**
     * Check if we are using a device that only supports the LEGACY hardware level.
     * <p/>
     * Call this only with {@link #mCameraStateLock} held.
     *
     * @return true if this is a legacy device.
     */
    private boolean isLegacyLocked() {
        return mCharacteristics.get(CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL) == CameraCharacteristics.INFO_SUPPORTED_HARDWARE_LEVEL_LEGACY;
    }

    /**
     * Start the timer for the pre-capture sequence.
     * <p/>
     * Call this only with {@link #mCameraStateLock} held.
     */
    private void startTimerLocked() {
        mCaptureTimer = SystemClock.elapsedRealtime();
    }

    /**
     * Check if the timer for the pre-capture sequence has been hit.
     * <p/>
     * Call this only with {@link #mCameraStateLock} held.
     *
     * @return true if the timeout occurred.
     */
    private boolean hitTimeoutLocked() {
        return (SystemClock.elapsedRealtime() - mCaptureTimer) > PRECAPTURE_TIMEOUT_MS;
    }


}