Back to project page qrcode-android.
The source code is released under:
MIT License
If you think the Android project qrcode-android listed in this page is inappropriate, such as containing malicious code/tools or violating the copyright, please email info at java2s dot com, thanks.
/* * Copyright (C) 2008 ZXing authors//from ww w . j a va2 s . c om * * 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.zxing.client.android.camera; import android.content.Context; import android.graphics.Point; import android.graphics.Rect; import android.hardware.Camera; import android.os.Build; import android.os.Handler; import android.util.DisplayMetrics; import android.util.Log; import android.view.Display; import android.view.Surface; import android.view.SurfaceHolder; import android.view.WindowManager; import com.google.zxing.PlanarYUVLuminanceSource; import com.google.zxing.client.android.camera.open.OpenCameraManager; import java.io.IOException; /** * This object wraps the Camera service object and expects to be the only one talking to it. The * implementation encapsulates the steps needed to take preview-sized images, which are used for * both preview and decoding. * * @author dswitkin@google.com (Daniel Switkin) */ public final class CameraManager { private static final String TAG = CameraManager.class.getSimpleName(); private static final int MIN_FRAME_WIDTH = 240; private static final int MIN_FRAME_HEIGHT = 240; private static final int MAX_FRAME_WIDTH = 960; // = 1920/2 private static final int MAX_FRAME_HEIGHT = 540; // = 1080/2 private final Context context; private final CameraConfigurationManager configManager; private Camera camera; private AutoFocusManager autoFocusManager; private Rect framingRect; private Rect framingRectInPreview; private boolean initialized; private boolean previewing; private int requestedFramingRectWidth; private int requestedFramingRectHeight; /** * Preview frames are delivered here, which we pass on to the registered handler. Make sure to * clear the handler so it will only receive one message. */ private final PreviewCallback previewCallback; private int lastRotationAngle; public CameraManager(Context context) { this.context = context; this.configManager = new CameraConfigurationManager(context); previewCallback = new PreviewCallback(configManager); } /** * Opens the camera driver and initializes the hardware parameters. * * @param holder The surface object which the camera will draw preview frames into. * @throws IOException Indicates the camera driver failed to open. */ public synchronized void openDriver(SurfaceHolder holder) throws IOException { Camera theCamera = camera; if (theCamera == null) { theCamera = new OpenCameraManager().build().open(); if (theCamera == null) { throw new IOException(); } camera = theCamera; } theCamera.setPreviewDisplay(holder); if (!initialized) { initialized = true; configManager.initFromCameraParameters(theCamera); if (requestedFramingRectWidth > 0 && requestedFramingRectHeight > 0) { setManualFramingRect(requestedFramingRectWidth, requestedFramingRectHeight); requestedFramingRectWidth = 0; requestedFramingRectHeight = 0; } } Camera.Parameters parameters = theCamera.getParameters(); String parametersFlattened = parameters == null ? null : parameters.flatten(); // Save these, temporarily try { configManager.setDesiredCameraParameters(theCamera); forceSetCameraOrientation(); // PR:LivotovLabs/zxscanlib ?camera?orientation???CaptureActivity?? } catch (RuntimeException re) { // Driver failed Log.w(TAG, "Camera rejected parameters. Setting only minimal safe-mode parameters"); Log.i(TAG, "Resetting to saved camera params: " + parametersFlattened); // Reset: if (parametersFlattened != null) { parameters = theCamera.getParameters(); parameters.unflatten(parametersFlattened); try { theCamera.setParameters(parameters); configManager.setDesiredCameraParameters(theCamera); } catch (RuntimeException re2) { // Well, darn. Give up Log.w(TAG, "Camera rejected even safe-mode parameters! No configuration"); } } } } public synchronized boolean isOpen() { return camera != null; } /** * Closes the camera driver if still in use. */ public synchronized void closeDriver() { if (camera != null) { camera.release(); camera = null; // Make sure to clear these each time we close the camera, so that any scanning rect // requested by intent is forgotten. framingRect = null; framingRectInPreview = null; } } /** * Asks the camera hardware to begin drawing preview frames to the screen. */ public synchronized void startPreview() { Camera theCamera = camera; if (theCamera != null && !previewing) { theCamera.startPreview(); previewing = true; autoFocusManager = new AutoFocusManager(context, camera); } } /** * Tells the camera to stop drawing preview frames. */ public synchronized void stopPreview() { if (autoFocusManager != null) { autoFocusManager.stop(); autoFocusManager = null; } if (camera != null && previewing) { camera.stopPreview(); previewCallback.setHandler(null, 0); previewing = false; } } /** * Convenience method for {@link com.google.zxing.client.android.CaptureActivity} */ public synchronized void setTorch(boolean newSetting) { if (newSetting != configManager.getTorchState(camera)) { if (camera != null) { if (autoFocusManager != null) { autoFocusManager.stop(); } configManager.setTorch(camera, newSetting); if (autoFocusManager != null) { autoFocusManager.start(); } } } } /** * A single preview frame will be returned to the handler supplied. The data will arrive as byte[] * in the message.obj field, with width and height encoded as message.arg1 and message.arg2, * respectively. * * @param handler The handler to send the message to. * @param message The what field of the message to be sent. */ public synchronized void requestPreviewFrame(Handler handler, int message) { Camera theCamera = camera; if (theCamera != null && previewing) { previewCallback.setHandler(handler, message); theCamera.setOneShotPreviewCallback(previewCallback); } } /** * Calculates the framing rect which the UI should draw to show the user where to place the * barcode. This target helps with alignment as well as forces the user to hold the device * far enough away to ensure the image will be in focus. * * @return The rectangle to draw on screen in window coordinates. */ public synchronized Rect getFramingRect() { if (framingRect == null) { if (camera == null) { return null; } Point screenResolution = configManager.getScreenResolution(); if (screenResolution == null) { // Called early, before init even finished return null; } int width = findDesiredDimensionInRange(screenResolution.x, MIN_FRAME_WIDTH, MAX_FRAME_WIDTH); int height = findDesiredDimensionInRange(screenResolution.y, MIN_FRAME_HEIGHT, MAX_FRAME_HEIGHT); int leftOffset = (screenResolution.x - width) / 2; int topOffset = (screenResolution.y - height) / 2; framingRect = new Rect(leftOffset, topOffset, leftOffset + width, topOffset + height); Log.d(TAG, "Calculated framing rect: " + framingRect); } return framingRect; } private static int findDesiredDimensionInRange(int resolution, int hardMin, int hardMax) { int dim = resolution / 2; // Target 50% of each dimension if (dim < hardMin) { return hardMin; } if (dim > hardMax) { return hardMax; } return dim; } /** * Like {@link #getFramingRect} but coordinates are in terms of the preview frame, * not UI / screen. */ public synchronized Rect getFramingRectInPreview() { if (framingRectInPreview == null) { Rect framingRect = getFramingRect(); if (framingRect == null) { return null; } Rect rect = new Rect(framingRect); Point cameraResolution = configManager.getCameraResolution(); Point screenResolution = configManager.getScreenResolution(); if (cameraResolution == null || screenResolution == null) { // Called early, before init even finished return null; } rect.left = rect.left * cameraResolution.x / screenResolution.x; rect.right = rect.right * cameraResolution.x / screenResolution.x; rect.top = rect.top * cameraResolution.y / screenResolution.y; rect.bottom = rect.bottom * cameraResolution.y / screenResolution.y; framingRectInPreview = rect; } return framingRectInPreview; } /** * Allows third party apps to specify the scanning rectangle dimensions, rather than determine * them automatically based on screen resolution. * * @param width The width in pixels to scan. * @param height The height in pixels to scan. */ public synchronized void setManualFramingRect(int width, int height) { if (initialized) { Point screenResolution = configManager.getScreenResolution(); if (width > screenResolution.x) { width = screenResolution.x; } if (height > screenResolution.y) { height = screenResolution.y; } int leftOffset = (screenResolution.x - width) / 2; int topOffset = (screenResolution.y - height) / 2; framingRect = new Rect(leftOffset, topOffset, leftOffset + width, topOffset + height); Log.d(TAG, "Calculated manual framing rect: " + framingRect); framingRectInPreview = null; } else { requestedFramingRectWidth = width; requestedFramingRectHeight = height; } } /** * A factory method to build the appropriate LuminanceSource object based on the format * of the preview buffers, as described by Camera.Parameters. * * @param data A preview frame. * @param width The width of the image. * @param height The height of the image. * @return A PlanarYUVLuminanceSource instance. */ public PlanarYUVLuminanceSource buildLuminanceSource(byte[] data, int width, int height) { Rect rect = getFramingRectInPreview(); if (rect == null) { return null; } // Go ahead and assume it's YUV rather than die. return new PlanarYUVLuminanceSource(data, width, height, rect.left, rect.top, rect.width(), rect.height(), false); } public synchronized void forceSetCameraOrientation() { if (Build.VERSION.SDK_INT > 7) { lastRotationAngle = -1; setCameraOrientation(); } } public synchronized void setCameraOrientation() { if (camera != null && Build.VERSION.SDK_INT > 8) { try { WindowManager mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE); Display display = mWindowManager.getDefaultDisplay(); int angle = Surface.ROTATION_0; if (lastRotationAngle == angle) { return; } boolean tablet = isTablet(); angle = display.getRotation(); switch (angle) { case Surface.ROTATION_0: camera.setDisplayOrientation(tablet ? 0 : 90); break; case Surface.ROTATION_90: camera.setDisplayOrientation(tablet ? 270 : 0); break; case Surface.ROTATION_180: camera.setDisplayOrientation(tablet ? 90 : 0); break; case Surface.ROTATION_270: camera.setDisplayOrientation(tablet ? 90 : 180); break; } lastRotationAngle = angle; } catch (Throwable err) { err.printStackTrace(); } } } private boolean isTablet() { WindowManager mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE); Display display = mWindowManager.getDefaultDisplay(); DisplayMetrics displayMetrics = new DisplayMetrics(); display.getMetrics(displayMetrics); int width = displayMetrics.widthPixels / displayMetrics.densityDpi; int height = displayMetrics.heightPixels / displayMetrics.densityDpi; double screenDiagonal = Math.sqrt(width * width + height * height); return (screenDiagonal >= 6); } }