Initial commit

lib/src/main/java/com/king/zxing/camera/CameraManager.java

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+package com.king.zxing.camera;
+
+/*
+ * Copyright (C) 2008 ZXing authors
+ *
+ * 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.
+ */
+
+
+import android.content.Context;
+import android.graphics.Point;
+import android.graphics.Rect;
+import android.hardware.Camera;
+import android.os.Handler;
+import android.util.Log;
+import android.view.SurfaceHolder;
+import com.google.zxing.PlanarYUVLuminanceSource;
+import com.king.zxing.camera.open.OpenCamera;
+import com.king.zxing.camera.open.OpenCameraInterface;
+
+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)
+ */
+@SuppressWarnings("deprecation") // camera APIs
+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 = 1200; // = 5/8 * 1920
+    private static final int MAX_FRAME_HEIGHT = 675; // = 5/8 * 1080
+
+    private final Context context;
+    private final CameraConfigurationManager configManager;
+    private OpenCamera camera;
+    private AutoFocusManager autoFocusManager;
+    private Rect framingRect;
+    private Rect framingRectInPreview;
+    private boolean initialized;
+    private boolean previewing;
+    private int requestedCameraId = OpenCameraInterface.NO_REQUESTED_CAMERA;
+    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;
+
+    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 {
+        OpenCamera theCamera = camera;
+        if (theCamera == null) {
+            theCamera = OpenCameraInterface.open(requestedCameraId);
+            if (theCamera == null) {
+                throw new IOException("Camera.open() failed to return object from driver");
+            }
+            camera = theCamera;
+        }
+
+        if (!initialized) {
+            initialized = true;
+            configManager.initFromCameraParameters(theCamera);
+            if (requestedFramingRectWidth > 0 && requestedFramingRectHeight > 0) {
+                setManualFramingRect(requestedFramingRectWidth, requestedFramingRectHeight);
+                requestedFramingRectWidth = 0;
+                requestedFramingRectHeight = 0;
+            }
+        }
+
+        Camera cameraObject = theCamera.getCamera();
+        Camera.Parameters parameters = cameraObject.getParameters();
+        String parametersFlattened = parameters == null ? null : parameters.flatten(); // Save these, temporarily
+        try {
+            configManager.setDesiredCameraParameters(theCamera, false);
+        } 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 = cameraObject.getParameters();
+                parameters.unflatten(parametersFlattened);
+                try {
+                    cameraObject.setParameters(parameters);
+                    configManager.setDesiredCameraParameters(theCamera, true);
+                } catch (RuntimeException re2) {
+                    // Well, darn. Give up
+                    Log.w(TAG, "Camera rejected even safe-mode parameters! No configuration");
+                }
+            }
+        }
+        cameraObject.setPreviewDisplay(holder);
+
+    }
+
+    public synchronized boolean isOpen() {
+        return camera != null;
+    }
+
+    public OpenCamera getOpenCamera() {
+        return camera;
+    }
+
+    /**
+     * Closes the camera driver if still in use.
+     */
+    public synchronized void closeDriver() {
+        if (camera != null) {
+            camera.getCamera().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() {
+        OpenCamera theCamera = camera;
+        if (theCamera != null && !previewing) {
+            theCamera.getCamera().startPreview();
+            previewing = true;
+            autoFocusManager = new AutoFocusManager(context, theCamera.getCamera());
+        }
+    }
+
+    /**
+     * Tells the camera to stop drawing preview frames.
+     */
+    public synchronized void stopPreview() {
+        if (autoFocusManager != null) {
+            autoFocusManager.stop();
+            autoFocusManager = null;
+        }
+        if (camera != null && previewing) {
+            camera.getCamera().stopPreview();
+            previewCallback.setHandler(null, 0);
+            previewing = false;
+        }
+    }
+
+    /**
+     * Convenience method for {@link com.king.zxing.CaptureActivity}
+     *
+     * @param newSetting if {@code true}, light should be turned on if currently off. And vice versa.
+     */
+    public synchronized void setTorch(boolean newSetting) {
+        OpenCamera theCamera = camera;
+        if (theCamera != null && newSetting != configManager.getTorchState(theCamera.getCamera())) {
+            boolean wasAutoFocusManager = autoFocusManager != null;
+            if (wasAutoFocusManager) {
+                autoFocusManager.stop();
+                autoFocusManager = null;
+            }
+            configManager.setTorch(theCamera.getCamera(), newSetting);
+            if (wasAutoFocusManager) {
+                autoFocusManager = new AutoFocusManager(context, theCamera.getCamera());
+                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) {
+        OpenCamera theCamera = camera;
+        if (theCamera != null && previewing) {
+            previewCallback.setHandler(handler, message);
+            theCamera.getCamera().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 = 5 * resolution / 8; // Target 5/8 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.
+     *
+     * @return {@link Rect} expressing barcode scan area in terms of the preview size
+     */
+    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 camera ID, rather than determine
+     * it automatically based on available cameras and their orientation.
+     *
+     * @param cameraId camera ID of the camera to use. A negative value means "no preference".
+     */
+    public synchronized void setManualCameraId(int cameraId) {
+        requestedCameraId = cameraId;
+    }
+
+    /**
+     * 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);
+    }
+
+}