Java tutorial
/* * Copyright (C) 2016 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.google.android.cameraview; import android.annotation.SuppressLint; import android.graphics.SurfaceTexture; import android.hardware.Camera; import android.os.Build; import android.support.v4.util.SparseArrayCompat; import android.view.SurfaceHolder; import java.io.IOException; import java.util.List; import java.util.Set; import java.util.SortedSet; import java.util.TreeSet; import java.util.concurrent.atomic.AtomicBoolean; @SuppressWarnings("deprecation") class Camera1 extends CameraViewImpl { private static final int INVALID_CAMERA_ID = -1; private static final SparseArrayCompat<String> FLASH_MODES = new SparseArrayCompat<>(); static { FLASH_MODES.put(Constants.FLASH_OFF, Camera.Parameters.FLASH_MODE_OFF); FLASH_MODES.put(Constants.FLASH_ON, Camera.Parameters.FLASH_MODE_ON); FLASH_MODES.put(Constants.FLASH_TORCH, Camera.Parameters.FLASH_MODE_TORCH); FLASH_MODES.put(Constants.FLASH_AUTO, Camera.Parameters.FLASH_MODE_AUTO); FLASH_MODES.put(Constants.FLASH_RED_EYE, Camera.Parameters.FLASH_MODE_RED_EYE); } private int mCameraId; private final AtomicBoolean isPictureCaptureInProgress = new AtomicBoolean(false); Camera mCamera; private Camera.Parameters mCameraParameters; private final Camera.CameraInfo mCameraInfo = new Camera.CameraInfo(); private final SizeMap mPreviewSizes = new SizeMap(); private final SizeMap mPictureSizes = new SizeMap(); private AspectRatio mAspectRatio; private boolean mShowingPreview; private boolean mAutoFocus; private int mFacing; private int mFlash; private int mDisplayOrientation; Camera1(Callback callback, PreviewImpl preview) { super(callback, preview); preview.setCallback(new PreviewImpl.Callback() { @Override public void onSurfaceChanged() { if (mCamera != null) { setUpPreview(); adjustCameraParameters(); } } }); } @Override boolean start() { chooseCamera(); if (!openCamera()) { return false; } if (mPreview.isReady()) { setUpPreview(); } mShowingPreview = true; mCamera.startPreview(); return true; } @Override void stop() { if (mCamera != null) { mCamera.stopPreview(); } mShowingPreview = false; releaseCamera(); } // Suppresses Camera#setPreviewTexture @SuppressLint("NewApi") void setUpPreview() { try { if (mPreview.getOutputClass() == SurfaceHolder.class) { final boolean needsToStopPreview = mShowingPreview && Build.VERSION.SDK_INT < 14; if (needsToStopPreview) { mCamera.stopPreview(); } mCamera.setPreviewDisplay(mPreview.getSurfaceHolder()); if (needsToStopPreview) { mCamera.startPreview(); } } else { mCamera.setPreviewTexture((SurfaceTexture) mPreview.getSurfaceTexture()); } } catch (IOException e) { throw new RuntimeException(e); } } @Override boolean isCameraOpened() { return mCamera != null; } @Override void setFacing(int facing) { if (mFacing == facing) { return; } mFacing = facing; if (isCameraOpened()) { stop(); start(); } } @Override int getFacing() { return mFacing; } @Override Set<AspectRatio> getSupportedAspectRatios() { SizeMap idealAspectRatios = mPreviewSizes; Set<AspectRatio> ratios = new TreeSet<>(idealAspectRatios.ratios()); for (AspectRatio aspectRatio : ratios) { if (mPictureSizes.sizes(aspectRatio) == null) { idealAspectRatios.remove(aspectRatio); } } return idealAspectRatios.ratios(); } @Override boolean setAspectRatio(AspectRatio ratio) { if (mAspectRatio == null || !isCameraOpened()) { // Handle this later when camera is opened mAspectRatio = ratio; return true; } else if (!mAspectRatio.equals(ratio)) { final Set<Size> sizes = mPreviewSizes.sizes(ratio); if (sizes == null) { throw new UnsupportedOperationException(ratio + " is not supported"); } else { mAspectRatio = ratio; adjustCameraParameters(); return true; } } return false; } @Override AspectRatio getAspectRatio() { return mAspectRatio; } @Override void setAutoFocus(boolean autoFocus) { if (mAutoFocus == autoFocus) { return; } if (setAutoFocusInternal(autoFocus)) { mCamera.setParameters(mCameraParameters); } } @Override boolean getAutoFocus() { if (!isCameraOpened()) { return mAutoFocus; } String focusMode = mCameraParameters.getFocusMode(); return focusMode != null && focusMode.contains("continuous"); } @Override void setFlash(int flash) { if (flash == mFlash) { return; } if (setFlashInternal(flash)) { mCamera.setParameters(mCameraParameters); } } @Override int getFlash() { return mFlash; } @Override void takePicture() { if (!isCameraOpened()) { throw new IllegalStateException("Camera is not ready. Call start() before takePicture()."); } if (getAutoFocus()) { mCamera.cancelAutoFocus(); mCamera.autoFocus(new Camera.AutoFocusCallback() { @Override public void onAutoFocus(boolean success, Camera camera) { takePictureInternal(); } }); } else { takePictureInternal(); } } void takePictureInternal() { if (!isPictureCaptureInProgress.getAndSet(true)) { mCamera.takePicture(null, null, null, new Camera.PictureCallback() { @Override public void onPictureTaken(byte[] data, Camera camera) { isPictureCaptureInProgress.set(false); mCallback.onPictureTaken(data); if (!isCameraOpened()) return; camera.cancelAutoFocus(); camera.startPreview(); } }); } } @Override void setDisplayOrientation(int displayOrientation) { if (mDisplayOrientation == displayOrientation) { return; } mDisplayOrientation = displayOrientation; if (isCameraOpened()) { mCameraParameters.setRotation(calcCameraRotation(displayOrientation)); mCamera.setParameters(mCameraParameters); final boolean needsToStopPreview = mShowingPreview && Build.VERSION.SDK_INT < 14; if (needsToStopPreview) { mCamera.stopPreview(); } mCamera.setDisplayOrientation(calcDisplayOrientation(displayOrientation)); if (needsToStopPreview) { mCamera.startPreview(); } } } /** * This rewrites {@link #mCameraId} and {@link #mCameraInfo}. */ private void chooseCamera() { for (int i = 0, count = Camera.getNumberOfCameras(); i < count; i++) { Camera.getCameraInfo(i, mCameraInfo); if (mCameraInfo.facing == mFacing) { mCameraId = i; return; } } mCameraId = INVALID_CAMERA_ID; } private boolean openCamera() { if (mCamera != null) { releaseCamera(); } mCamera = null; if (mCameraId == INVALID_CAMERA_ID) { mCallback.onCameraNotAvailable(); return false; } try { mCamera = Camera.open(mCameraId); } catch (RuntimeException ex) { mCamera = null; mCallback.onCameraNotAvailable(); return false; } assert (mCamera != null); mCameraParameters = mCamera.getParameters(); // Supported preview sizes mPreviewSizes.clear(); for (Camera.Size size : mCameraParameters.getSupportedPreviewSizes()) { mPreviewSizes.add(new Size(size.width, size.height)); } // Supported picture sizes; mPictureSizes.clear(); for (Camera.Size size : mCameraParameters.getSupportedPictureSizes()) { mPictureSizes.add(new Size(size.width, size.height)); } // AspectRatio if (mAspectRatio == null) { mAspectRatio = Constants.DEFAULT_ASPECT_RATIO; } adjustCameraParameters(); mCamera.setDisplayOrientation(calcDisplayOrientation(mDisplayOrientation)); mCallback.onCameraOpened(); return true; } private AspectRatio chooseAspectRatio() { AspectRatio r = null; for (AspectRatio ratio : mPreviewSizes.ratios()) { r = ratio; if (ratio.equals(Constants.DEFAULT_ASPECT_RATIO)) { return ratio; } } return r; } void adjustCameraParameters() { SortedSet<Size> sizes = mPreviewSizes.sizes(mAspectRatio); if (sizes == null) { // Not supported mAspectRatio = chooseAspectRatio(); sizes = mPreviewSizes.sizes(mAspectRatio); } Size size = chooseOptimalSize(sizes); // Always re-apply camera parameters // Largest picture size in this ratio final Size pictureSize = mPictureSizes.sizes(mAspectRatio).last(); if (mShowingPreview) { mCamera.stopPreview(); } mCameraParameters.setPreviewSize(size.getWidth(), size.getHeight()); mCameraParameters.setPictureSize(pictureSize.getWidth(), pictureSize.getHeight()); mCameraParameters.setRotation(calcCameraRotation(mDisplayOrientation)); setAutoFocusInternal(mAutoFocus); setFlashInternal(mFlash); mCamera.setParameters(mCameraParameters); if (mShowingPreview) { mCamera.startPreview(); } } @SuppressWarnings("SuspiciousNameCombination") private Size chooseOptimalSize(SortedSet<Size> sizes) { if (!mPreview.isReady()) { // Not yet laid out return sizes.first(); // Return the smallest size } int desiredWidth; int desiredHeight; final int surfaceWidth = mPreview.getWidth(); final int surfaceHeight = mPreview.getHeight(); if (isLandscape(mDisplayOrientation)) { desiredWidth = surfaceHeight; desiredHeight = surfaceWidth; } else { desiredWidth = surfaceWidth; desiredHeight = surfaceHeight; } Size result = null; for (Size size : sizes) { // Iterate from small to large if (desiredWidth <= size.getWidth() && desiredHeight <= size.getHeight()) { return size; } result = size; } return result; } private void releaseCamera() { if (mCamera != null) { mCamera.release(); mCamera = null; mCallback.onCameraClosed(); } } /** * Calculate display orientation * https://developer.android.com/reference/android/hardware/Camera.html#setDisplayOrientation(int) * * This calculation is used for orienting the preview * * Note: This is not the same calculation as the camera rotation * * @param screenOrientationDegrees Screen orientation in degrees * @return Number of degrees required to rotate preview */ private int calcDisplayOrientation(int screenOrientationDegrees) { if (mCameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) { return (360 - (mCameraInfo.orientation + screenOrientationDegrees) % 360) % 360; } else { // back-facing return (mCameraInfo.orientation - screenOrientationDegrees + 360) % 360; } } /** * Calculate camera rotation * * This calculation is applied to the output JPEG either via Exif Orientation tag * or by actually transforming the bitmap. (Determined by vendor camera API implementation) * * Note: This is not the same calculation as the display orientation * * @param screenOrientationDegrees Screen orientation in degrees * @return Number of degrees to rotate image in order for it to view correctly. */ private int calcCameraRotation(int screenOrientationDegrees) { if (mCameraInfo.facing == Camera.CameraInfo.CAMERA_FACING_FRONT) { return (mCameraInfo.orientation + screenOrientationDegrees) % 360; } else { // back-facing final int landscapeFlip = isLandscape(screenOrientationDegrees) ? 180 : 0; return (mCameraInfo.orientation + screenOrientationDegrees + landscapeFlip) % 360; } } /** * Test if the supplied orientation is in landscape. * * @param orientationDegrees Orientation in degrees (0,90,180,270) * @return True if in landscape, false if portrait */ private boolean isLandscape(int orientationDegrees) { return (orientationDegrees == Constants.LANDSCAPE_90 || orientationDegrees == Constants.LANDSCAPE_270); } /** * @return {@code true} if {@link #mCameraParameters} was modified. */ private boolean setAutoFocusInternal(boolean autoFocus) { mAutoFocus = autoFocus; if (isCameraOpened()) { final List<String> modes = mCameraParameters.getSupportedFocusModes(); if (autoFocus && modes.contains(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE)) { mCameraParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE); } else if (autoFocus && modes.contains(Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO)) { mCameraParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_VIDEO); } else if (autoFocus && modes.contains(Camera.Parameters.FOCUS_MODE_AUTO)) { mCameraParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO); } else if (modes.contains(Camera.Parameters.FOCUS_MODE_FIXED)) { mCameraParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_FIXED); } else if (modes.contains(Camera.Parameters.FOCUS_MODE_INFINITY)) { mCameraParameters.setFocusMode(Camera.Parameters.FOCUS_MODE_INFINITY); } else { mCameraParameters.setFocusMode(modes.get(0)); } return true; } else { return false; } } /** * @return {@code true} if {@link #mCameraParameters} was modified. */ private boolean setFlashInternal(int flash) { if (isCameraOpened()) { List<String> modes = mCameraParameters.getSupportedFlashModes(); String mode = FLASH_MODES.get(flash); if (modes != null && modes.contains(mode)) { mCameraParameters.setFlashMode(mode); mFlash = flash; return true; } String currentMode = FLASH_MODES.get(mFlash); if (modes == null || !modes.contains(currentMode)) { mCameraParameters.setFlashMode(Camera.Parameters.FLASH_MODE_OFF); mFlash = Constants.FLASH_OFF; return true; } return false; } else { mFlash = flash; return false; } } }