关于滤镜

/解码算法 YUV to RGB //Method from Ketai project! void decodeYUV420SP(int[] rgb, byte[] yuv420sp, int width, int height) {     final int frameSize = width * height;     for (int j = 0, yp = 0; j < height; j++) {         int uvp = frameSize + (j >> 1) * width, u = 0, v = 0;         for (int i = 0; i < width; i++, yp++) {             int y = (0xff & ((int) yuv420sp[yp])) - 16;             if (y < 0) y = 0;             if ((i & 1) == 0) {                 v = (0xff & yuv420sp[uvp++]) - 128;                 u = (0xff & yuv420sp[uvp++]) - 128;             }             int y1192 = 1192 * y;             int r = (y1192 + 1634 * v);             int g = (y1192 - 833 * v - 400 * u);             int b = (y1192 + 2066 * u);             if (r < 0) r = 0;             else if (r > 262143) r = 262143;             if (g < 0) g = 0;             else if (g > 262143) g = 262143;             if (b < 0) b = 0;             else if (b > 262143) b = 262143;             rgb[yp] = 0xff000000 | ((r << 6) & 0xff0000)                       | ((g >> 2) & 0xff00) | ((b >> 10) & 0xff);         }     } }创建surfaceView显示摄像头画面public class Preview extends SurfaceView implements SurfaceHolder.Callback{      private static final String TAG = "Preview";    SurfaceHolder mHolder;     Camera mCamera;    Filter filter;    FilterFunction filterFunction;    //This variable is responsible for getting and setting the camera settings     private Parameters parameters;     //this variable stores the camera preview size     private Size previewSize;     //this array stores the pixels as hexadecimal pairs     private int[] pixels;         public Preview(Context context) {         super(context);         // Install a SurfaceHolder.Callback so we get notified when the         // underlying surface is created and destroyed.         mHolder = getHolder();         mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);         mHolder.addCallback(this);         filterFunction = new FilterFunction();        filter = new Filter();    }     public void surfaceCreated(SurfaceHolder holder) {         if(mCamera == null){            // The Surface has been created, acquire the camera and tell it where             // to draw.             mCamera = Camera.open();            mCamera.setPreviewCallback(mPreviewCallback);            try {                mCamera.setPreviewDisplay(holder);                ///initialize the variables                 parameters = mCamera.getParameters();                 previewSize = parameters.getPreviewSize();                 pixels = new int[previewSize.width * previewSize.height];            }catch (Exception e) {                mCamera.release();                 mCamera = null;                 Log.v(TAG, e.getLocalizedMessage());            }        }    }     public void surfaceDestroyed(SurfaceHolder holder) {         // Surface will be destroyed when we return, so stop the preview.         // Because the CameraDevice object is not a shared resource, it's very         // important to release it when the activity is paused.         mCamera.stopPreview();         mCamera.release();         mCamera = null;     }     public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) {         Camera.Parameters parameters = mCamera.getParameters();// 获得相机参数        parameters.setPreviewSize(320, 240); // 设置预览图像大小        parameters.setPictureFormat(PixelFormat.JPEG); // 设置照片格式        mCamera.setParameters(parameters);// 设置相机参数        mCamera.startPreview();    }         private PreviewCallback mPreviewCallback = new PreviewCallback() {        public void onPreviewFrame(byte[] data, Camera camera) {        if(data != null) {            int imageWidth = mCamera.getParameters().getPreviewSize().width;            int imageHeight = mCamera.getParameters().getPreviewSize().height;            int RGBData[] = new int[imageWidth * imageHeight];            decodeYUV420SP(RGBData, data, imageWidth, imageHeight); // 解码            bm = Bitmap.createBitmap(RGBData, imageWidth,            imageHeight, Config.ARGB_8888);           //滤镜处理        }    }};