package org.tensorflow.yolo.view; import android.Manifest; import android.app.Activity; import android.app.Fragment; import android.content.Context; import android.content.pm.PackageManager; import android.content.res.Configuration; import android.graphics.ImageFormat; import android.graphics.Matrix; 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.CaptureRequest; import android.hardware.camera2.params.StreamConfigurationMap; import android.media.ImageReader; import android.media.ImageReader.OnImageAvailableListener; import android.os.Bundle; import android.os.Handler; import android.os.HandlerThread; 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 org.tensorflow.yolo.R; import org.tensorflow.yolo.util.comparator.CompareSizesByArea; import org.tensorflow.yolo.view.components.ErrorDialog; import java.util.ArrayList; import java.util.Arrays; import java.util.Collections; import java.util.List; import java.util.concurrent.Semaphore; import java.util.concurrent.TimeUnit; import static org.tensorflow.yolo.Config.LOGGING_TAG; /** * Camera connection fragment * Modified by Zoltan Szabo */ public class CameraConnectionFragment extends Fragment { private static final Size DESIRED_PREVIEW_SIZE = new Size(640, 480); /** * The camera preview size will be chosen to be the smallest frame by pixel size capable of * containing a DESIRED_SIZE x DESIRED_SIZE square. */ private static final int MINIMUM_PREVIEW_SIZE = 320; /** * Conversion from screen rotation to JPEG orientation. */ private static final SparseIntArray ORIENTATIONS = new SparseIntArray(); 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); } private static final String FRAGMENT_DIALOG = "dialog"; /** * A {@link Semaphore} to prevent the app from exiting before closing the camera. */ private final Semaphore cameraOpenCloseLock = new Semaphore(1); /** * A {@link OnImageAvailableListener} to receive frames as they are available. */ private OnImageAvailableListener imageListener; /** * A {@link ConnectionListener} to notify the caller activity */ private ConnectionListener cameraConnectionListener; /** * ID of the current {@link CameraDevice}. */ private String cameraId; /** * An {@link AutoFitTextureView} for camera preview. */ private AutoFitTextureView textureView; /** * A {@link CameraCaptureSession } for camera preview. */ private CameraCaptureSession captureSession; /** * A reference to the opened {@link CameraDevice}. */ private CameraDevice cameraDevice; /** * The rotation in degrees of the camera sensor from the display. */ private Integer sensorOrientation; /** * The {@link android.util.Size} of camera preview. */ private Size previewSize; /** * An additional thread for running tasks that shouldn't block the UI. */ private HandlerThread backgroundThread; /** * A {@link Handler} for running tasks in the background. */ private Handler backgroundHandler; /** * An {@link ImageReader} that handles preview frame capture. */ private ImageReader previewReader; /** * {@link android.hardware.camera2.CaptureRequest.Builder} for the camera preview */ private CaptureRequest.Builder previewRequestBuilder; /** * {@link CaptureRequest} generated by {@link #previewRequestBuilder} */ private CaptureRequest previewRequest; @Override public View onCreateView(final LayoutInflater inflater, final ViewGroup container, final Bundle savedInstanceState) { return inflater.inflate(R.layout.camera_connection_fragment, container, false); } @Override public void onViewCreated(final View view, final Bundle savedInstanceState) { textureView = (AutoFitTextureView) view.findViewById(R.id.texture); } @Override public void onActivityCreated(final Bundle savedInstanceState) { super.onActivityCreated(savedInstanceState); } @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 (textureView.isAvailable()) { openCamera(textureView.getWidth(), textureView.getHeight()); } else { textureView.setSurfaceTextureListener(new TextureView.SurfaceTextureListener() { @Override public void onSurfaceTextureAvailable(final SurfaceTexture texture, final int width, final int height) { openCamera(width, height); } @Override public void onSurfaceTextureSizeChanged(final SurfaceTexture texture, final int width, final int height) { configureTransform(width, height); } @Override public boolean onSurfaceTextureDestroyed(final SurfaceTexture texture) { return true; } @Override public void onSurfaceTextureUpdated(final SurfaceTexture texture) { } }); } } @Override public void onPause() { closeCamera(); stopBackgroundThread(); super.onPause(); } public void addConnectionListener(final ConnectionListener cameraConnectionListener) { this.cameraConnectionListener = cameraConnectionListener; } public void addImageAvailableListener(final OnImageAvailableListener imageListener) { this.imageListener = imageListener; } /** * Callback for Activities to use to initialize their data once the * selected preview size is known. */ public interface ConnectionListener { void onPreviewSizeChosen(Size size, int cameraRotation); } /** * Given {@code choices} of {@code Size}s supported by a camera, chooses the smallest one whose * width and height are at least as large as the minimum of both, or an exact match if possible. * * @param choices The list of sizes that the camera supports for the intended output class * @return The optimal {@code Size}, or an arbitrary one if none were big enough */ private static Size chooseOptimalSize(final Size[] choices) { final int minSize = Math.max(Math.min(DESIRED_PREVIEW_SIZE.getWidth(), DESIRED_PREVIEW_SIZE.getHeight()), MINIMUM_PREVIEW_SIZE); // Collect the supported resolutions that are at least as big as the preview Surface final List<Size> bigEnough = new ArrayList(); for (final Size option : choices) { if (option.equals(DESIRED_PREVIEW_SIZE)) { return DESIRED_PREVIEW_SIZE; } if (option.getHeight() >= minSize && option.getWidth() >= minSize) { bigEnough.add(option); } } // Pick the smallest of those, assuming we found any return (bigEnough.size() > 0) ? Collections.min(bigEnough, new CompareSizesByArea()) : choices[0]; } /** * 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(() -> Toast.makeText(activity, text, Toast.LENGTH_SHORT).show()); } } /** * Sets up member variables related to camera. */ private void setUpCameraOutputs() { final CameraManager manager = (CameraManager) getActivity().getSystemService(Context.CAMERA_SERVICE); try { for (final String cameraId : manager.getCameraIdList()) { final CameraCharacteristics characteristics = manager.getCameraCharacteristics(cameraId); // We don't use a front facing camera in this sample. final Integer facing = characteristics.get(CameraCharacteristics.LENS_FACING); if (facing != null && facing == CameraCharacteristics.LENS_FACING_FRONT) { continue; } final StreamConfigurationMap map = characteristics.get(CameraCharacteristics.SCALER_STREAM_CONFIGURATION_MAP); if (map == null) { continue; } sensorOrientation = characteristics.get(CameraCharacteristics.SENSOR_ORIENTATION); // 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. previewSize = chooseOptimalSize(map.getOutputSizes(SurfaceTexture.class)); // We fit the aspect ratio of TextureView to the size of preview we picked. final int orientation = getResources().getConfiguration().orientation; if (orientation == Configuration.ORIENTATION_LANDSCAPE) { textureView.setAspectRatio(previewSize.getWidth(), previewSize.getHeight()); } else { textureView.setAspectRatio(previewSize.getHeight(), previewSize.getWidth()); } this.cameraId = cameraId; } } catch (final CameraAccessException ex) { Log.e(LOGGING_TAG, "Exception: " + ex.getMessage()); } catch (final NullPointerException ex) { ErrorDialog.newInstance(getString(R.string.camera_error)) .show(getChildFragmentManager(), FRAGMENT_DIALOG); throw new RuntimeException(getString(R.string.camera_error)); } cameraConnectionListener.onPreviewSizeChosen(previewSize, sensorOrientation); } /** * Opens the camera specified by {@link CameraConnectionFragment#cameraId}. */ private void openCamera(final int width, final int height) { setUpCameraOutputs(); configureTransform(width, height); final Activity activity = getActivity(); /** * {@link android.hardware.camera2.CameraDevice.StateCallback} * is called when {@link CameraDevice} changes its state. */ final CameraManager manager = (CameraManager) activity.getSystemService(Context.CAMERA_SERVICE); try { if (!cameraOpenCloseLock.tryAcquire(2500, TimeUnit.MILLISECONDS)) { throw new RuntimeException("Time out waiting to lock camera opening."); } if (activity.checkSelfPermission(Manifest.permission.CAMERA) == PackageManager.PERMISSION_GRANTED) { manager.openCamera(cameraId, new CameraDevice.StateCallback() { @Override public void onOpened(final CameraDevice cameraDevice) { // This method is called when the camera is opened. We start camera preview here. cameraOpenCloseLock.release(); CameraConnectionFragment.this.cameraDevice = cameraDevice; createCameraPreviewSession(); } @Override public void onDisconnected(final CameraDevice cameraDevice) { cameraOpenCloseLock.release(); cameraDevice.close(); CameraConnectionFragment.this.cameraDevice = null; } @Override public void onError(final CameraDevice cameraDevice, final int error) { cameraOpenCloseLock.release(); cameraDevice.close(); CameraConnectionFragment.this.cameraDevice = null; final Activity activity = getActivity(); if (null != activity) { activity.finish(); } } }, backgroundHandler); } else { requestPermissions(new String[]{Manifest.permission.CAMERA}, 1); } } catch (final CameraAccessException ex) { Log.e(LOGGING_TAG, "Exception: " + ex.getMessage()); } catch (final InterruptedException ex) { throw new RuntimeException("Interrupted while trying to lock camera opening.", ex); } } /** * Closes the current {@link CameraDevice}. */ private void closeCamera() { try { cameraOpenCloseLock.acquire(); if (null != captureSession) { captureSession.close(); captureSession = null; } if (null != cameraDevice) { cameraDevice.close(); cameraDevice = null; } if (null != previewReader) { previewReader.close(); previewReader = null; } } catch (final InterruptedException e) { throw new RuntimeException("Interrupted while trying to lock camera closing.", e); } finally { cameraOpenCloseLock.release(); } } /** * Starts a background thread and its {@link Handler}. */ private void startBackgroundThread() { backgroundThread = new HandlerThread("ImageListener"); backgroundThread.start(); backgroundHandler = new Handler(backgroundThread.getLooper()); } /** * Stops the background thread and its {@link Handler}. */ private void stopBackgroundThread() { backgroundThread.quitSafely(); try { backgroundThread.join(); backgroundThread = null; backgroundHandler = null; } catch (final InterruptedException ex) { Log.e(LOGGING_TAG, "Exception: " + ex.getMessage()); } } /** * Creates a new {@link CameraCaptureSession} for camera preview. */ private void createCameraPreviewSession() { try { final SurfaceTexture texture = textureView.getSurfaceTexture(); assert texture != null; // We configure the size of default buffer to be the size of camera preview we want. texture.setDefaultBufferSize(previewSize.getWidth(), previewSize.getHeight()); // This is the output Surface we need to start preview. final Surface surface = new Surface(texture); // We set up a CaptureRequest.Builder with the output Surface. previewRequestBuilder = cameraDevice.createCaptureRequest(CameraDevice.TEMPLATE_PREVIEW); previewRequestBuilder.addTarget(surface); Log.i(LOGGING_TAG, String.format("Opening camera preview: " + previewSize.getWidth() + "x" + previewSize.getHeight())); // Create the reader for the preview frames. previewReader = ImageReader.newInstance(previewSize.getWidth(), previewSize.getHeight(), ImageFormat.YUV_420_888, 2); previewReader.setOnImageAvailableListener(imageListener, backgroundHandler); previewRequestBuilder.addTarget(previewReader.getSurface()); // Here, we create a CameraCaptureSession for camera preview. cameraDevice.createCaptureSession(Arrays.asList(surface, previewReader.getSurface()), getCaptureSessionStateCallback(), null); } catch (final CameraAccessException ex) { Log.e(LOGGING_TAG, "Exception: " + ex.getMessage()); } } private CameraCaptureSession.StateCallback getCaptureSessionStateCallback() { return new CameraCaptureSession.StateCallback() { @Override public void onConfigured(final CameraCaptureSession cameraCaptureSession) { // The camera is already closed if (null == cameraDevice) { return; } // When the session is ready, we start displaying the preview. captureSession = cameraCaptureSession; try { // Auto focus should be continuous for camera preview. previewRequestBuilder.set(CaptureRequest.CONTROL_AF_MODE, CaptureRequest.CONTROL_AF_MODE_CONTINUOUS_PICTURE); // Flash is automatically enabled when necessary. previewRequestBuilder.set(CaptureRequest.CONTROL_AE_MODE, CaptureRequest.CONTROL_AE_MODE_ON_AUTO_FLASH); // Finally, we start displaying the camera preview. previewRequest = previewRequestBuilder.build(); captureSession.setRepeatingRequest(previewRequest, null, backgroundHandler); } catch (final CameraAccessException ex) { Log.e(LOGGING_TAG, "Exception: " + ex.getMessage()); } } @Override public void onConfigureFailed(final CameraCaptureSession cameraCaptureSession) { showToast("Failed"); } }; } /** * 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(final int viewWidth, final int viewHeight) { final Activity activity = getActivity(); if (null == textureView || null == previewSize || null == activity) { return; } final int rotation = activity.getWindowManager().getDefaultDisplay().getRotation(); final Matrix matrix = new Matrix(); final RectF viewRect = new RectF(0, 0, viewWidth, viewHeight); final RectF bufferRect = new RectF(0, 0, previewSize.getHeight(), previewSize.getWidth()); final float centerX = viewRect.centerX(); final 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); final float scale = Math.max( (float) viewHeight / previewSize.getHeight(), (float) viewWidth / previewSize.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); } textureView.setTransform(matrix); } }