|  | /* | 
|  | * Copyright 2014 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 com.example.android.camera2basic; | 
|  |  | 
|  | import android.Manifest; | 
|  | import android.app.Activity; | 
|  | import android.app.AlertDialog; | 
|  | import android.app.Dialog; | 
|  | import android.app.DialogFragment; | 
|  | import android.app.Fragment; | 
|  | import android.content.Context; | 
|  | import android.content.DialogInterface; | 
|  | import android.content.pm.PackageManager; | 
|  | import android.content.res.Configuration; | 
|  | import android.graphics.ImageFormat; | 
|  | import android.graphics.Matrix; | 
|  | import android.graphics.Point; | 
|  | import android.graphics.RectF; | 
|  | import android.graphics.SurfaceTexture; | 
|  | 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.CaptureRequest; | 
|  | import android.hardware.camera2.CaptureResult; | 
|  | import android.hardware.camera2.TotalCaptureResult; | 
|  | import android.hardware.camera2.params.StreamConfigurationMap; | 
|  | import android.media.Image; | 
|  | import android.media.ImageReader; | 
|  | import android.os.Bundle; | 
|  | import android.os.Handler; | 
|  | import android.os.HandlerThread; | 
|  | import android.support.annotation.NonNull; | 
|  | import android.support.v13.app.FragmentCompat; | 
|  | import android.support.v4.content.ContextCompat; | 
|  | import android.util.Log; | 
|  | import android.util.Size; | 
|  | import android.util.SparseIntArray; | 
|  | import android.view.LayoutInflater; | 
|  | import android.view.Surface; | 
|  | import android.view.TextureView; | 
|  | import android.view.View; | 
|  | import android.view.ViewGroup; | 
|  | import android.widget.Toast; | 
|  |  | 
|  | import java.io.File; | 
|  | import java.io.FileOutputStream; | 
|  | import java.io.IOException; | 
|  | import java.nio.ByteBuffer; | 
|  | import java.util.ArrayList; | 
|  | import java.util.Arrays; | 
|  | import java.util.Collections; | 
|  | import java.util.Comparator; | 
|  | import java.util.List; | 
|  | import java.util.concurrent.Semaphore; | 
|  | import java.util.concurrent.TimeUnit; | 
|  |  | 
|  | public class Camera2BasicFragment extends Fragment | 
|  | implements View.OnClickListener, FragmentCompat.OnRequestPermissionsResultCallback { | 
|  |  | 
|  | /** | 
|  | * Conversion from screen rotation to JPEG orientation. | 
|  | */ | 
|  | private static final SparseIntArray ORIENTATIONS = new SparseIntArray(); | 
|  | private static final int REQUEST_CAMERA_PERMISSION = 1; | 
|  | private static final String FRAGMENT_DIALOG = "dialog"; | 
|  |  | 
|  | static { | 
|  | ORIENTATIONS.append(Surface.ROTATION_0, 90); | 
|  | ORIENTATIONS.append(Surface.ROTATION_90, 0); | 
|  | ORIENTATIONS.append(Surface.ROTATION_180, 270); | 
|  | ORIENTATIONS.append(Surface.ROTATION_270, 180); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Tag for the {@link Log}. | 
|  | */ | 
|  | private static final String TAG = "Camera2BasicFragment"; | 
|  |  | 
|  | /** | 
|  | * Camera state: Showing camera preview. | 
|  | */ | 
|  | private static final int STATE_PREVIEW = 0; | 
|  |  | 
|  | /** | 
|  | * Camera state: Waiting for the focus to be locked. | 
|  | */ | 
|  | private static final int STATE_WAITING_LOCK = 1; | 
|  |  | 
|  | /** | 
|  | * Camera state: Waiting for the exposure to be precapture state. | 
|  | */ | 
|  | private static final int STATE_WAITING_PRECAPTURE = 2; | 
|  |  | 
|  | /** | 
|  | * Camera state: Waiting for the exposure state to be something other than precapture. | 
|  | */ | 
|  | private static final int STATE_WAITING_NON_PRECAPTURE = 3; | 
|  |  | 
|  | /** | 
|  | * Camera state: Picture was taken. | 
|  | */ | 
|  | private static final int STATE_PICTURE_TAKEN = 4; | 
|  |  | 
|  | /** | 
|  | * Max preview width that is guaranteed by Camera2 API | 
|  | */ | 
|  | private static final int MAX_PREVIEW_WIDTH = 1920; | 
|  |  | 
|  | /** | 
|  | * Max preview height that is guaranteed by Camera2 API | 
|  | */ | 
|  | private static final int MAX_PREVIEW_HEIGHT = 1080; | 
|  |  | 
|  | /** | 
|  | * {@link TextureView.SurfaceTextureListener} handles several lifecycle events on a | 
|  | * {@link TextureView}. | 
|  | */ | 
|  | private final TextureView.SurfaceTextureListener mSurfaceTextureListener | 
|  | = new TextureView.SurfaceTextureListener() { | 
|  |  | 
|  | @Override | 
|  | public void onSurfaceTextureAvailable(SurfaceTexture texture, int width, int height) { | 
|  | openCamera(width, height); | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onSurfaceTextureSizeChanged(SurfaceTexture texture, int width, int height) { | 
|  | configureTransform(width, height); | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public boolean onSurfaceTextureDestroyed(SurfaceTexture texture) { | 
|  | return true; | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onSurfaceTextureUpdated(SurfaceTexture texture) { | 
|  | } | 
|  |  | 
|  | }; | 
|  |  | 
|  | /** | 
|  | * ID of the current {@link CameraDevice}. | 
|  | */ | 
|  | private String mCameraId; | 
|  |  | 
|  | /** | 
|  | * An {@link AutoFitTextureView} for camera preview. | 
|  | */ | 
|  | private AutoFitTextureView mTextureView; | 
|  |  | 
|  | /** | 
|  | * A {@link CameraCaptureSession } for camera preview. | 
|  | */ | 
|  | private CameraCaptureSession mCaptureSession; | 
|  |  | 
|  | /** | 
|  | * A reference to the opened {@link CameraDevice}. | 
|  | */ | 
|  | private CameraDevice mCameraDevice; | 
|  |  | 
|  | /** | 
|  | * The {@link android.util.Size} of camera preview. | 
|  | */ | 
|  | private Size mPreviewSize; | 
|  |  | 
|  | /** | 
|  | * {@link CameraDevice.StateCallback} is called when {@link CameraDevice} changes its state. | 
|  | */ | 
|  | private final CameraDevice.StateCallback mStateCallback = new CameraDevice.StateCallback() { | 
|  |  | 
|  | @Override | 
|  | public void onOpened(@NonNull CameraDevice cameraDevice) { | 
|  | // This method is called when the camera is opened.  We start camera preview here. | 
|  | mCameraOpenCloseLock.release(); | 
|  | mCameraDevice = cameraDevice; | 
|  | createCameraPreviewSession(); | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onDisconnected(@NonNull CameraDevice cameraDevice) { | 
|  | mCameraOpenCloseLock.release(); | 
|  | cameraDevice.close(); | 
|  | mCameraDevice = null; | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onError(@NonNull CameraDevice cameraDevice, int error) { | 
|  | mCameraOpenCloseLock.release(); | 
|  | cameraDevice.close(); | 
|  | mCameraDevice = null; | 
|  | Activity activity = getActivity(); | 
|  | if (null != activity) { | 
|  | activity.finish(); | 
|  | } | 
|  | } | 
|  |  | 
|  | }; | 
|  |  | 
|  | /** | 
|  | * An additional thread for running tasks that shouldn't block the UI. | 
|  | */ | 
|  | private HandlerThread mBackgroundThread; | 
|  |  | 
|  | /** | 
|  | * A {@link Handler} for running tasks in the background. | 
|  | */ | 
|  | private Handler mBackgroundHandler; | 
|  |  | 
|  | /** | 
|  | * An {@link ImageReader} that handles still image capture. | 
|  | */ | 
|  | private ImageReader mImageReader; | 
|  |  | 
|  | /** | 
|  | * This is the output file for our picture. | 
|  | */ | 
|  | private File mFile; | 
|  |  | 
|  | /** | 
|  | * This a callback object for the {@link ImageReader}. "onImageAvailable" will be called when a | 
|  | * still image is ready to be saved. | 
|  | */ | 
|  | private final ImageReader.OnImageAvailableListener mOnImageAvailableListener | 
|  | = new ImageReader.OnImageAvailableListener() { | 
|  |  | 
|  | @Override | 
|  | public void onImageAvailable(ImageReader reader) { | 
|  | mBackgroundHandler.post(new ImageSaver(reader.acquireNextImage(), mFile)); | 
|  | } | 
|  |  | 
|  | }; | 
|  |  | 
|  | /** | 
|  | * {@link CaptureRequest.Builder} for the camera preview | 
|  | */ | 
|  | private CaptureRequest.Builder mPreviewRequestBuilder; | 
|  |  | 
|  | /** | 
|  | * {@link CaptureRequest} generated by {@link #mPreviewRequestBuilder} | 
|  | */ | 
|  | private CaptureRequest mPreviewRequest; | 
|  |  | 
|  | /** | 
|  | * The current state of camera state for taking pictures. | 
|  | * | 
|  | * @see #mCaptureCallback | 
|  | */ | 
|  | private int mState = STATE_PREVIEW; | 
|  |  | 
|  | /** | 
|  | * A {@link Semaphore} to prevent the app from exiting before closing the camera. | 
|  | */ | 
|  | private Semaphore mCameraOpenCloseLock = new Semaphore(1); | 
|  |  | 
|  | /** | 
|  | * Whether the current camera device supports Flash or not. | 
|  | */ | 
|  | private boolean mFlashSupported; | 
|  |  | 
|  | /** | 
|  | * Orientation of the camera sensor | 
|  | */ | 
|  | private int mSensorOrientation; | 
|  |  | 
|  | /** | 
|  | * A {@link CameraCaptureSession.CaptureCallback} that handles events related to JPEG capture. | 
|  | */ | 
|  | private CameraCaptureSession.CaptureCallback mCaptureCallback | 
|  | = new CameraCaptureSession.CaptureCallback() { | 
|  |  | 
|  | private void process(CaptureResult result) { | 
|  | switch (mState) { | 
|  | case STATE_PREVIEW: { | 
|  | // We have nothing to do when the camera preview is working normally. | 
|  | break; | 
|  | } | 
|  | case STATE_WAITING_LOCK: { | 
|  | Integer afState = result.get(CaptureResult.CONTROL_AF_STATE); | 
|  | if (afState == null) { | 
|  | captureStillPicture(); | 
|  | } else if (CaptureResult.CONTROL_AF_STATE_FOCUSED_LOCKED == afState || | 
|  | CaptureResult.CONTROL_AF_STATE_NOT_FOCUSED_LOCKED == afState) { | 
|  | // CONTROL_AE_STATE can be null on some devices | 
|  | Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE); | 
|  | if (aeState == null || | 
|  | aeState == CaptureResult.CONTROL_AE_STATE_CONVERGED) { | 
|  | mState = STATE_PICTURE_TAKEN; | 
|  | captureStillPicture(); | 
|  | } else { | 
|  | runPrecaptureSequence(); | 
|  | } | 
|  | } | 
|  | break; | 
|  | } | 
|  | case STATE_WAITING_PRECAPTURE: { | 
|  | // CONTROL_AE_STATE can be null on some devices | 
|  | Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE); | 
|  | if (aeState == null || | 
|  | aeState == CaptureResult.CONTROL_AE_STATE_PRECAPTURE || | 
|  | aeState == CaptureRequest.CONTROL_AE_STATE_FLASH_REQUIRED) { | 
|  | mState = STATE_WAITING_NON_PRECAPTURE; | 
|  | } | 
|  | break; | 
|  | } | 
|  | case STATE_WAITING_NON_PRECAPTURE: { | 
|  | // CONTROL_AE_STATE can be null on some devices | 
|  | Integer aeState = result.get(CaptureResult.CONTROL_AE_STATE); | 
|  | if (aeState == null || aeState != CaptureResult.CONTROL_AE_STATE_PRECAPTURE) { | 
|  | mState = STATE_PICTURE_TAKEN; | 
|  | captureStillPicture(); | 
|  | } | 
|  | break; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onCaptureProgressed(@NonNull CameraCaptureSession session, | 
|  | @NonNull CaptureRequest request, | 
|  | @NonNull CaptureResult partialResult) { | 
|  | process(partialResult); | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onCaptureCompleted(@NonNull CameraCaptureSession session, | 
|  | @NonNull CaptureRequest request, | 
|  | @NonNull TotalCaptureResult result) { | 
|  | process(result); | 
|  | } | 
|  |  | 
|  | }; | 
|  |  | 
|  | /** | 
|  | * Shows a {@link Toast} on the UI thread. | 
|  | * | 
|  | * @param text The message to show | 
|  | */ | 
|  | private void showToast(final String text) { | 
|  | final Activity activity = getActivity(); | 
|  | if (activity != null) { | 
|  | activity.runOnUiThread(new Runnable() { | 
|  | @Override | 
|  | public void run() { | 
|  | Toast.makeText(activity, text, Toast.LENGTH_SHORT).show(); | 
|  | } | 
|  | }); | 
|  | } | 
|  | } | 
|  |  | 
|  | /** | 
|  | * 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]; | 
|  | } | 
|  | } | 
|  |  | 
|  | public static Camera2BasicFragment newInstance() { | 
|  | return new Camera2BasicFragment(); | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public View onCreateView(LayoutInflater inflater, ViewGroup container, | 
|  | Bundle savedInstanceState) { | 
|  | return inflater.inflate(R.layout.fragment_camera2_basic, container, false); | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onViewCreated(final View view, Bundle savedInstanceState) { | 
|  | view.findViewById(R.id.picture).setOnClickListener(this); | 
|  | view.findViewById(R.id.info).setOnClickListener(this); | 
|  | mTextureView = (AutoFitTextureView) view.findViewById(R.id.texture); | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onActivityCreated(Bundle savedInstanceState) { | 
|  | super.onActivityCreated(savedInstanceState); | 
|  | mFile = new File(getActivity().getExternalFilesDir(null), "pic.jpg"); | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onResume() { | 
|  | super.onResume(); | 
|  | startBackgroundThread(); | 
|  |  | 
|  | // When the screen is turned off and turned back on, the SurfaceTexture is already | 
|  | // available, and "onSurfaceTextureAvailable" will not be called. In that case, we can open | 
|  | // a camera and start preview from here (otherwise, we wait until the surface is ready in | 
|  | // the SurfaceTextureListener). | 
|  | if (mTextureView.isAvailable()) { | 
|  | openCamera(mTextureView.getWidth(), mTextureView.getHeight()); | 
|  | } else { | 
|  | mTextureView.setSurfaceTextureListener(mSurfaceTextureListener); | 
|  | } | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onPause() { | 
|  | closeCamera(); | 
|  | stopBackgroundThread(); | 
|  | super.onPause(); | 
|  | } | 
|  |  | 
|  | private void requestCameraPermission() { | 
|  | if (FragmentCompat.shouldShowRequestPermissionRationale(this, Manifest.permission.CAMERA)) { | 
|  | new ConfirmationDialog().show(getChildFragmentManager(), FRAGMENT_DIALOG); | 
|  | } else { | 
|  | FragmentCompat.requestPermissions(this, new String[]{Manifest.permission.CAMERA}, | 
|  | REQUEST_CAMERA_PERMISSION); | 
|  | } | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, | 
|  | @NonNull int[] grantResults) { | 
|  | if (requestCode == REQUEST_CAMERA_PERMISSION) { | 
|  | if (grantResults.length != 1 || grantResults[0] != PackageManager.PERMISSION_GRANTED) { | 
|  | ErrorDialog.newInstance(getString(R.string.request_permission)) | 
|  | .show(getChildFragmentManager(), FRAGMENT_DIALOG); | 
|  | } | 
|  | } else { | 
|  | super.onRequestPermissionsResult(requestCode, permissions, grantResults); | 
|  | } | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Sets up member variables related to camera. | 
|  | * | 
|  | * @param width  The width of available size for camera preview | 
|  | * @param height The height of available size for camera preview | 
|  | */ | 
|  | private void setUpCameraOutputs(int width, int height) { | 
|  | Activity activity = getActivity(); | 
|  | CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE); | 
|  | try { | 
|  | for (String cameraId : manager.getCameraIdList()) { | 
|  | CameraCharacteristics characteristics | 
|  | = manager.getCameraCharacteristics(cameraId); | 
|  |  | 
|  | // We don't use a front facing camera in this sample. | 
|  | Integer facing = characteristics.get(CameraCharacteristics.LENS_FACING); | 
|  | if (facing != null && facing == CameraCharacteristics.LENS_FACING_FRONT) { | 
|  | continue; | 
|  | } | 
|  |  | 
|  | StreamConfigurationMap map = characteristics.get( | 
|  | CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP); | 
|  | if (map == null) { | 
|  | continue; | 
|  | } | 
|  |  | 
|  | // For still image captures, we use the largest available size. | 
|  | Size largest = Collections.max( | 
|  | Arrays.asList(map.getOutputSizes(ImageFormat.JPEG)), | 
|  | new CompareSizesByArea()); | 
|  | mImageReader = ImageReader.newInstance(largest.getWidth(), largest.getHeight(), | 
|  | ImageFormat.JPEG, /*maxImages*/2); | 
|  | mImageReader.setOnImageAvailableListener( | 
|  | mOnImageAvailableListener, mBackgroundHandler); | 
|  |  | 
|  | // Find out if we need to swap dimension to get the preview size relative to sensor | 
|  | // coordinate. | 
|  | int displayRotation = activity.getWindowManager().getDefaultDisplay().getRotation(); | 
|  | //noinspection ConstantConditions | 
|  | mSensorOrientation = characteristics.get(CameraCharacteristics.SENSOR_ORIENTATION); | 
|  | boolean swappedDimensions = false; | 
|  | switch (displayRotation) { | 
|  | case Surface.ROTATION_0: | 
|  | case Surface.ROTATION_180: | 
|  | if (mSensorOrientation == 90 || mSensorOrientation == 270) { | 
|  | swappedDimensions = true; | 
|  | } | 
|  | break; | 
|  | case Surface.ROTATION_90: | 
|  | case Surface.ROTATION_270: | 
|  | if (mSensorOrientation == 0 || mSensorOrientation == 180) { | 
|  | swappedDimensions = true; | 
|  | } | 
|  | break; | 
|  | default: | 
|  | Log.e(TAG, "Display rotation is invalid: " + displayRotation); | 
|  | } | 
|  |  | 
|  | Point displaySize = new Point(); | 
|  | activity.getWindowManager().getDefaultDisplay().getSize(displaySize); | 
|  | int rotatedPreviewWidth = width; | 
|  | int rotatedPreviewHeight = height; | 
|  | int maxPreviewWidth = displaySize.x; | 
|  | int maxPreviewHeight = displaySize.y; | 
|  |  | 
|  | if (swappedDimensions) { | 
|  | rotatedPreviewWidth = height; | 
|  | rotatedPreviewHeight = width; | 
|  | maxPreviewWidth = displaySize.y; | 
|  | maxPreviewHeight = displaySize.x; | 
|  | } | 
|  |  | 
|  | if (maxPreviewWidth > MAX_PREVIEW_WIDTH) { | 
|  | maxPreviewWidth = MAX_PREVIEW_WIDTH; | 
|  | } | 
|  |  | 
|  | if (maxPreviewHeight > MAX_PREVIEW_HEIGHT) { | 
|  | maxPreviewHeight = MAX_PREVIEW_HEIGHT; | 
|  | } | 
|  |  | 
|  | // Danger, W.R.! Attempting to use too large a preview size could  exceed the camera | 
|  | // bus' bandwidth limitation, resulting in gorgeous previews but the storage of | 
|  | // garbage capture data. | 
|  | mPreviewSize = chooseOptimalSize(map.getOutputSizes(SurfaceTexture.class), | 
|  | rotatedPreviewWidth, rotatedPreviewHeight, maxPreviewWidth, | 
|  | maxPreviewHeight, largest); | 
|  |  | 
|  | // We fit the aspect ratio of TextureView to the size of preview we picked. | 
|  | int orientation = getResources().getConfiguration().orientation; | 
|  | if (orientation == Configuration.ORIENTATION_LANDSCAPE) { | 
|  | mTextureView.setAspectRatio( | 
|  | mPreviewSize.getWidth(), mPreviewSize.getHeight()); | 
|  | } else { | 
|  | mTextureView.setAspectRatio( | 
|  | mPreviewSize.getHeight(), mPreviewSize.getWidth()); | 
|  | } | 
|  |  | 
|  | // Check if the flash is supported. | 
|  | Boolean available = characteristics.get(CameraCharacteristics.FLASH_INFO_AVAILABLE); | 
|  | mFlashSupported = available == null ? false : available; | 
|  |  | 
|  | mCameraId = cameraId; | 
|  | return; | 
|  | } | 
|  | } catch (CameraAccessException e) { | 
|  | e.printStackTrace(); | 
|  | } catch (NullPointerException e) { | 
|  | // Currently an NPE is thrown when the Camera2API is used but not supported on the | 
|  | // device this code runs. | 
|  | ErrorDialog.newInstance(getString(R.string.camera_error)) | 
|  | .show(getChildFragmentManager(), FRAGMENT_DIALOG); | 
|  | } | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Opens the camera specified by {@link Camera2BasicFragment#mCameraId}. | 
|  | */ | 
|  | private void openCamera(int width, int height) { | 
|  | if (ContextCompat.checkSelfPermission(getActivity(), Manifest.permission.CAMERA) | 
|  | != PackageManager.PERMISSION_GRANTED) { | 
|  | requestCameraPermission(); | 
|  | return; | 
|  | } | 
|  | setUpCameraOutputs(width, height); | 
|  | configureTransform(width, height); | 
|  | Activity activity = getActivity(); | 
|  | CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE); | 
|  | try { | 
|  | if (!mCameraOpenCloseLock.tryAcquire(2500, TimeUnit.MILLISECONDS)) { | 
|  | throw new RuntimeException("Time out waiting to lock camera opening."); | 
|  | } | 
|  | manager.openCamera(mCameraId, mStateCallback, mBackgroundHandler); | 
|  | } catch (CameraAccessException e) { | 
|  | e.printStackTrace(); | 
|  | } catch (InterruptedException e) { | 
|  | throw new RuntimeException("Interrupted while trying to lock camera opening.", e); | 
|  | } | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Closes the current {@link CameraDevice}. | 
|  | */ | 
|  | private void closeCamera() { | 
|  | try { | 
|  | mCameraOpenCloseLock.acquire(); | 
|  | if (null != mCaptureSession) { | 
|  | mCaptureSession.close(); | 
|  | mCaptureSession = null; | 
|  | } | 
|  | if (null != mCameraDevice) { | 
|  | mCameraDevice.close(); | 
|  | mCameraDevice = null; | 
|  | } | 
|  | if (null != mImageReader) { | 
|  | mImageReader.close(); | 
|  | mImageReader = 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(); | 
|  | mBackgroundHandler = new Handler(mBackgroundThread.getLooper()); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Stops the background thread and its {@link Handler}. | 
|  | */ | 
|  | private void stopBackgroundThread() { | 
|  | mBackgroundThread.quitSafely(); | 
|  | try { | 
|  | mBackgroundThread.join(); | 
|  | mBackgroundThread = null; | 
|  | mBackgroundHandler = null; | 
|  | } catch (InterruptedException e) { | 
|  | e.printStackTrace(); | 
|  | } | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Creates a new {@link CameraCaptureSession} for camera preview. | 
|  | */ | 
|  | private void createCameraPreviewSession() { | 
|  | try { | 
|  | SurfaceTexture texture = mTextureView.getSurfaceTexture(); | 
|  | assert texture != null; | 
|  |  | 
|  | // 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, mImageReader.getSurface()), | 
|  | new CameraCaptureSession.StateCallback() { | 
|  |  | 
|  | @Override | 
|  | public void onConfigured(@NonNull CameraCaptureSession cameraCaptureSession) { | 
|  | // The camera is already closed | 
|  | if (null == mCameraDevice) { | 
|  | return; | 
|  | } | 
|  |  | 
|  | // When the session is ready, we start displaying the preview. | 
|  | mCaptureSession = cameraCaptureSession; | 
|  | try { | 
|  | // Auto focus should be continuous for camera preview. | 
|  | mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, | 
|  | CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE); | 
|  | // Flash is automatically enabled when necessary. | 
|  | setAutoFlash(mPreviewRequestBuilder); | 
|  |  | 
|  | // Finally, we start displaying the camera preview. | 
|  | mPreviewRequest = mPreviewRequestBuilder.build(); | 
|  | mCaptureSession.setRepeatingRequest(mPreviewRequest, | 
|  | mCaptureCallback, mBackgroundHandler); | 
|  | } catch (CameraAccessException e) { | 
|  | e.printStackTrace(); | 
|  | } | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onConfigureFailed( | 
|  | @NonNull CameraCaptureSession cameraCaptureSession) { | 
|  | showToast("Failed"); | 
|  | } | 
|  | }, null | 
|  | ); | 
|  | } catch (CameraAccessException e) { | 
|  | e.printStackTrace(); | 
|  | } | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Configures the necessary {@link android.graphics.Matrix} transformation to `mTextureView`. | 
|  | * This method should be called after the camera preview size is determined in | 
|  | * setUpCameraOutputs and also the size of `mTextureView` is fixed. | 
|  | * | 
|  | * @param viewWidth  The width of `mTextureView` | 
|  | * @param viewHeight The height of `mTextureView` | 
|  | */ | 
|  | private void configureTransform(int viewWidth, int viewHeight) { | 
|  | Activity activity = getActivity(); | 
|  | if (null == mTextureView || null == mPreviewSize || null == activity) { | 
|  | return; | 
|  | } | 
|  | int rotation = activity.getWindowManager().getDefaultDisplay().getRotation(); | 
|  | Matrix matrix = new Matrix(); | 
|  | RectF viewRect = new RectF(0, 0, viewWidth, viewHeight); | 
|  | RectF bufferRect = new RectF(0, 0, mPreviewSize.getHeight(), mPreviewSize.getWidth()); | 
|  | float centerX = viewRect.centerX(); | 
|  | float centerY = viewRect.centerY(); | 
|  | if (Surface.ROTATION_90 == rotation || Surface.ROTATION_270 == rotation) { | 
|  | bufferRect.offset(centerX - bufferRect.centerX(), centerY - bufferRect.centerY()); | 
|  | matrix.setRectToRect(viewRect, bufferRect, Matrix.ScaleToFit.FILL); | 
|  | float scale = Math.max( | 
|  | (float) viewHeight / mPreviewSize.getHeight(), | 
|  | (float) viewWidth / mPreviewSize.getWidth()); | 
|  | matrix.postScale(scale, scale, centerX, centerY); | 
|  | matrix.postRotate(90 * (rotation - 2), centerX, centerY); | 
|  | } else if (Surface.ROTATION_180 == rotation) { | 
|  | matrix.postRotate(180, centerX, centerY); | 
|  | } | 
|  | mTextureView.setTransform(matrix); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Initiate a still image capture. | 
|  | */ | 
|  | private void takePicture() { | 
|  | lockFocus(); | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Lock the focus as the first step for a still image capture. | 
|  | */ | 
|  | private void lockFocus() { | 
|  | try { | 
|  | // This is how to tell the camera to lock focus. | 
|  | mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, | 
|  | CameraMetadata.CONTROL_AF_TRIGGER_START); | 
|  | // Tell #mCaptureCallback to wait for the lock. | 
|  | mState = STATE_WAITING_LOCK; | 
|  | mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback, | 
|  | mBackgroundHandler); | 
|  | } catch (CameraAccessException e) { | 
|  | e.printStackTrace(); | 
|  | } | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Run the precapture sequence for capturing a still image. This method should be called when | 
|  | * we get a response in {@link #mCaptureCallback} from {@link #lockFocus()}. | 
|  | */ | 
|  | private void runPrecaptureSequence() { | 
|  | try { | 
|  | // This is how to tell the camera to trigger. | 
|  | mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER, | 
|  | CaptureRequest.CONTROL_AE_PRECAPTURE_TRIGGER_START); | 
|  | // Tell #mCaptureCallback to wait for the precapture sequence to be set. | 
|  | mState = STATE_WAITING_PRECAPTURE; | 
|  | mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback, | 
|  | mBackgroundHandler); | 
|  | } catch (CameraAccessException e) { | 
|  | e.printStackTrace(); | 
|  | } | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Capture a still picture. This method should be called when we get a response in | 
|  | * {@link #mCaptureCallback} from both {@link #lockFocus()}. | 
|  | */ | 
|  | private void captureStillPicture() { | 
|  | 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(mImageReader.getSurface()); | 
|  |  | 
|  | // Use the same AE and AF modes as the preview. | 
|  | captureBuilder.set(CaptureRequest.CONTROL_AF_MODE, | 
|  | CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE); | 
|  | setAutoFlash(captureBuilder); | 
|  |  | 
|  | // Orientation | 
|  | int rotation = activity.getWindowManager().getDefaultDisplay().getRotation(); | 
|  | captureBuilder.set(CaptureRequest.JPEG_ORIENTATION, getOrientation(rotation)); | 
|  |  | 
|  | CameraCaptureSession.CaptureCallback CaptureCallback | 
|  | = new CameraCaptureSession.CaptureCallback() { | 
|  |  | 
|  | @Override | 
|  | public void onCaptureCompleted(@NonNull CameraCaptureSession session, | 
|  | @NonNull CaptureRequest request, | 
|  | @NonNull TotalCaptureResult result) { | 
|  | showToast("Saved: " + mFile); | 
|  | Log.d(TAG, mFile.toString()); | 
|  | unlockFocus(); | 
|  | } | 
|  | }; | 
|  |  | 
|  | mCaptureSession.stopRepeating(); | 
|  | mCaptureSession.capture(captureBuilder.build(), CaptureCallback, null); | 
|  | } catch (CameraAccessException e) { | 
|  | e.printStackTrace(); | 
|  | } | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Retrieves the JPEG orientation from the specified screen rotation. | 
|  | * | 
|  | * @param rotation The screen rotation. | 
|  | * @return The JPEG orientation (one of 0, 90, 270, and 360) | 
|  | */ | 
|  | private int getOrientation(int rotation) { | 
|  | // Sensor orientation is 90 for most devices, or 270 for some devices (eg. Nexus 5X) | 
|  | // We have to take that into account and rotate JPEG properly. | 
|  | // For devices with orientation of 90, we simply return our mapping from ORIENTATIONS. | 
|  | // For devices with orientation of 270, we need to rotate the JPEG 180 degrees. | 
|  | return (ORIENTATIONS.get(rotation) + mSensorOrientation + 270) % 360; | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Unlock the focus. This method should be called when still image capture sequence is | 
|  | * finished. | 
|  | */ | 
|  | private void unlockFocus() { | 
|  | try { | 
|  | // Reset the auto-focus trigger | 
|  | mPreviewRequestBuilder.set(CaptureRequest.CONTROL_AF_TRIGGER, | 
|  | CameraMetadata.CONTROL_AF_TRIGGER_CANCEL); | 
|  | setAutoFlash(mPreviewRequestBuilder); | 
|  | mCaptureSession.capture(mPreviewRequestBuilder.build(), mCaptureCallback, | 
|  | mBackgroundHandler); | 
|  | // After this, the camera will go back to the normal state of preview. | 
|  | mState = STATE_PREVIEW; | 
|  | mCaptureSession.setRepeatingRequest(mPreviewRequest, mCaptureCallback, | 
|  | mBackgroundHandler); | 
|  | } catch (CameraAccessException e) { | 
|  | e.printStackTrace(); | 
|  | } | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void onClick(View view) { | 
|  | switch (view.getId()) { | 
|  | case R.id.picture: { | 
|  | takePicture(); | 
|  | break; | 
|  | } | 
|  | case R.id.info: { | 
|  | Activity activity = getActivity(); | 
|  | if (null != activity) { | 
|  | new AlertDialog.Builder(activity) | 
|  | .setMessage(R.string.intro_message) | 
|  | .setPositiveButton(android.R.string.ok, null) | 
|  | .show(); | 
|  | } | 
|  | break; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | private void setAutoFlash(CaptureRequest.Builder requestBuilder) { | 
|  | if (mFlashSupported) { | 
|  | requestBuilder.set(CaptureRequest.CONTROL_AE_MODE, | 
|  | CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH); | 
|  | } | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Saves a JPEG {@link Image} into the specified {@link File}. | 
|  | */ | 
|  | private static class ImageSaver implements Runnable { | 
|  |  | 
|  | /** | 
|  | * The JPEG image | 
|  | */ | 
|  | private final Image mImage; | 
|  | /** | 
|  | * The file we save the image into. | 
|  | */ | 
|  | private final File mFile; | 
|  |  | 
|  | public ImageSaver(Image image, File file) { | 
|  | mImage = image; | 
|  | mFile = file; | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public void run() { | 
|  | ByteBuffer buffer = mImage.getPlanes()[0].getBuffer(); | 
|  | byte[] bytes = new byte[buffer.remaining()]; | 
|  | buffer.get(bytes); | 
|  | FileOutputStream output = null; | 
|  | try { | 
|  | output = new FileOutputStream(mFile); | 
|  | output.write(bytes); | 
|  | } catch (IOException e) { | 
|  | e.printStackTrace(); | 
|  | } finally { | 
|  | mImage.close(); | 
|  | if (null != output) { | 
|  | try { | 
|  | output.close(); | 
|  | } catch (IOException e) { | 
|  | e.printStackTrace(); | 
|  | } | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Compares two {@code Size}s based on their areas. | 
|  | */ | 
|  | 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()); | 
|  | } | 
|  |  | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Shows an error message dialog. | 
|  | */ | 
|  | public static class ErrorDialog extends DialogFragment { | 
|  |  | 
|  | private static final String ARG_MESSAGE = "message"; | 
|  |  | 
|  | public static ErrorDialog newInstance(String message) { | 
|  | ErrorDialog dialog = new ErrorDialog(); | 
|  | Bundle args = new Bundle(); | 
|  | args.putString(ARG_MESSAGE, message); | 
|  | dialog.setArguments(args); | 
|  | return dialog; | 
|  | } | 
|  |  | 
|  | @Override | 
|  | public Dialog onCreateDialog(Bundle savedInstanceState) { | 
|  | final Activity activity = getActivity(); | 
|  | return new AlertDialog.Builder(activity) | 
|  | .setMessage(getArguments().getString(ARG_MESSAGE)) | 
|  | .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() { | 
|  | @Override | 
|  | public void onClick(DialogInterface dialogInterface, int i) { | 
|  | activity.finish(); | 
|  | } | 
|  | }) | 
|  | .create(); | 
|  | } | 
|  |  | 
|  | } | 
|  |  | 
|  | /** | 
|  | * Shows OK/Cancel confirmation dialog about camera permission. | 
|  | */ | 
|  | public static class ConfirmationDialog extends DialogFragment { | 
|  |  | 
|  | @Override | 
|  | public Dialog onCreateDialog(Bundle savedInstanceState) { | 
|  | final Fragment parent = getParentFragment(); | 
|  | return new AlertDialog.Builder(getActivity()) | 
|  | .setMessage(R.string.request_permission) | 
|  | .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() { | 
|  | @Override | 
|  | public void onClick(DialogInterface dialog, int which) { | 
|  | FragmentCompat.requestPermissions(parent, | 
|  | new String[]{Manifest.permission.CAMERA}, | 
|  | REQUEST_CAMERA_PERMISSION); | 
|  | } | 
|  | }) | 
|  | .setNegativeButton(android.R.string.cancel, | 
|  | new DialogInterface.OnClickListener() { | 
|  | @Override | 
|  | public void onClick(DialogInterface dialog, int which) { | 
|  | Activity activity = parent.getActivity(); | 
|  | if (activity != null) { | 
|  | activity.finish(); | 
|  | } | 
|  | } | 
|  | }) | 
|  | .create(); | 
|  | } | 
|  | } | 
|  |  | 
|  | } |