编辑onPreviewFrame中的帧不会在录制的视频中出现编辑

时间:2013-10-04 07:45:19

标签: android android-camera android-mediarecorder

我正在尝试在onPreviewFrame功能中编辑视频帧。但是,在评估的视频帧中不进行编辑。

Follwoing是代码:

public class CameraPreview extends SurfaceView implements SurfaceHolder.Callback, PreviewCallback {
    private static final String TAG = "CameraPreview";

    private final Camera camera;
    private final CameraConfigurationManager configManager;



    public CameraPreview(Context context, Camera camera) {
        super(context);
        this.camera = camera;
        this.configManager = new CameraConfigurationManager(context);
        super.getHolder().addCallback(this);
        this.camera.setPreviewCallbackWithBuffer(CameraPreview.this);
        // required for API <= 11
        super.getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }

    public void surfaceCreated(SurfaceHolder holder) {
        Log.d(TAG, "surfaceCreated()");
        // now that we have the surface, we can start the preview
        try {
            this.camera.setPreviewDisplay(holder);
            this.camera.startPreview();
        } catch (IOException e) {
            Log.wtf(TAG, "Failed to start camera preview", e);
        }
    }

    public void surfaceDestroyed(SurfaceHolder holder) {
        // we will release the camera preview in our activity before this
        // happens
        Log.d(TAG, "surfaceDestroyed()");
    }

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {
        // our activity runs with screenOrientation="landscape" so we don't
        // care about surface changes
        Log.d(TAG, "surfaceChanged()");
    }

    @Override
    public void onPreviewFrame(byte[] data, Camera camera) {
        Log.d("HFI","In onPreviewFrame "+data.length);
        for (int i = 1000; i < 5000; i++) {
            data [i] = 0;
        }
        Point cameraResolution = configManager.getCameraResolution();
        int maxwidth = cameraResolution.x;
        int maxheight =cameraResolution.y;
//      YuvImage img = new YuvImage(data, camera.getParameters().getPreviewFormat(), 640, 480, null);
        YuvImage image = new YuvImage(data, camera.getParameters().getPreviewFormat(), maxwidth, maxheight, null);
        Rect rectangle = new Rect();
        rectangle.bottom = maxheight;
        rectangle.top = 0;
        rectangle.left = 0;
        rectangle.right = maxwidth;
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        image.compressToJpeg(rectangle, 95, output);

        // Decode the JPEG byte array from 'output' to 'Bitmap' object
        Bitmap bmp = BitmapFactory.decodeByteArray(output.toByteArray(), 0, output.size());
        bmp = convertToMutable(bmp);
        // Use 'Canvas' to draw text ont 'Bitmap'
        Canvas cv = new Canvas(bmp);

        // Prepare 'Paint' for text drawing
        Paint mPaint = new Paint();
        mPaint.setColor( Color.RED );
        mPaint.setStyle( Style.STROKE );
        mPaint.setTextSize(30);

        // Draw text on the 'Bitmap' image
        cv.drawText("Hello Camera", 10, 10, mPaint);

        // Reset the stream of 'output' for output writing.
        output.reset();

        // Compress current 'Bitmap' to 'output' as JPEG format
        bmp.compress(CompressFormat.JPEG, 95, output);

        data = getNV21(maxwidth, maxheight, bmp);

        //camera.addCallbackBuffer(getNV21(640, 480, bmp));
    }

     // untested function
    byte [] getNV21(int inputWidth, int inputHeight, Bitmap scaled) {

        int [] argb = new int[inputWidth * inputHeight];

        scaled.getPixels(argb, 0, inputWidth, 0, 0, inputWidth, inputHeight);

        byte [] yuv = new byte[inputWidth*inputHeight*3/2];
        encodeYUV420SP(yuv, argb, inputWidth, inputHeight);

        scaled.recycle();

        return yuv;
    }


    void encodeYUV420SP(byte[] yuv420sp, int[] argb, int width, int height) {
        final int frameSize = width * height;

        int yIndex = 0;
        int uvIndex = frameSize;

        int a, R, G, B, Y, U, V;
        int index = 0;
        for (int j = 0; j < height; j++) {
            for (int i = 0; i < width; i++) {

                a = (argb[index] & 0xff000000) >> 24; // a is not used obviously
                R = (argb[index] & 0xff0000) >> 16;
                G = (argb[index] & 0xff00) >> 8;
                B = (argb[index] & 0xff) >> 0;

                // well known RGB to YUV algorithm
                Y = ( (  66 * R + 129 * G +  25 * B + 128) >> 8) +  16;
                U = ( ( -38 * R -  74 * G + 112 * B + 128) >> 8) + 128;
                V = ( ( 112 * R -  94 * G -  18 * B + 128) >> 8) + 128;

                // NV21 has a plane of Y and interleaved planes of VU each sampled by a factor of 2
                //    meaning for every 4 Y pixels there are 1 V and 1 U.  Note the sampling is every other
                //    pixel AND every other scanline.
                yuv420sp[yIndex++] = (byte) ((Y < 0) ? 0 : ((Y > 255) ? 255 : Y));
                if (j % 2 == 0 && index % 2 == 0) { 
                    yuv420sp[uvIndex++] = (byte)((V<0) ? 0 : ((V > 255) ? 255 : V));
                    yuv420sp[uvIndex++] = (byte)((U<0) ? 0 : ((U > 255) ? 255 : U));
                }

                index ++;
            }
        }
    }

    /**
     * Converts a immutable bitmap to a mutable bitmap. This operation doesn't allocates
     * more memory that there is already allocated.
     * 
     * @param imgIn - Source image. It will be released, and should not be used more
     * @return a copy of imgIn, but muttable.
     */
    public static Bitmap convertToMutable(Bitmap imgIn) {
        try {
            //this is the file going to use temporally to save the bytes. 
            // This file will not be a image, it will store the raw image data.
            File file = new File(Environment.getExternalStorageDirectory() + File.separator + "temp.tmp");

            //Open an RandomAccessFile
            //Make sure you have added uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"
            //into AndroidManifest.xml file
            RandomAccessFile randomAccessFile = new RandomAccessFile(file, "rw");

            // get the width and height of the source bitmap.
            int width = imgIn.getWidth();
            int height = imgIn.getHeight();
            Config type = imgIn.getConfig();

            //Copy the byte to the file
            //Assume source bitmap loaded using options.inPreferredConfig = Config.ARGB_8888;
            FileChannel channel = randomAccessFile.getChannel();
            MappedByteBuffer map = channel.map(MapMode.READ_WRITE, 0, imgIn.getRowBytes()*height);
            imgIn.copyPixelsToBuffer(map);
            //recycle the source bitmap, this will be no longer used.
            imgIn.recycle();
            System.gc();// try to force the bytes from the imgIn to be released

            //Create a new bitmap to load the bitmap again. Probably the memory will be available. 
            imgIn = Bitmap.createBitmap(width, height, type);
            map.position(0);
            //load it back from temporary 
            imgIn.copyPixelsFromBuffer(map);
            //close the temporary file and channel , then delete that also
            channel.close();
            randomAccessFile.close();

            // delete the temp file
            file.delete();

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } 

        return imgIn;
    }
}

我已尝试this.camera.setPreviewCallback(CameraPreview.this);并遇到以下错误。

10-04 12:43:06.118: E/AndroidRuntime(3015): FATAL EXCEPTION: main
10-04 12:43:06.118: E/AndroidRuntime(3015): java.lang.RuntimeException: Method called after release()
10-04 12:43:06.118: E/AndroidRuntime(3015):     at android.hardware.Camera.setHasPreviewCallback(Native Method)
10-04 12:43:06.118: E/AndroidRuntime(3015):     at android.hardware.Camera.access$600(Camera.java:133)
10-04 12:43:06.118: E/AndroidRuntime(3015):     at android.hardware.Camera$EventHandler.handleMessage(Camera.java:792)
10-04 12:43:06.118: E/AndroidRuntime(3015):     at android.os.Handler.dispatchMessage(Handler.java:99)
10-04 12:43:06.118: E/AndroidRuntime(3015):     at android.os.Looper.loop(Looper.java:137)
10-04 12:43:06.118: E/AndroidRuntime(3015):     at android.app.ActivityThread.main(ActivityThread.java:4898)
10-04 12:43:06.118: E/AndroidRuntime(3015):     at java.lang.reflect.Method.invokeNative(Native Method)
10-04 12:43:06.118: E/AndroidRuntime(3015):     at java.lang.reflect.Method.invoke(Method.java:511)
10-04 12:43:06.118: E/AndroidRuntime(3015):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1006)
10-04 12:43:06.118: E/AndroidRuntime(3015):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:773)
10-04 12:43:06.118: E/AndroidRuntime(3015):     at dalvik.system.NativeStart.main(Native Method)

需要帮助。 Actualy我想在Frames上写文字和画图像。

1 个答案:

答案 0 :(得分:0)

在表面破坏后将预览回调设置为null:

public void surfaceDestroyed(SurfaceHolder holder) {
   this.camera.setPreviewCallbackWithBuffer(null);
    Log.d(TAG, "surfaceDestroyed()");
}