Btukfyl

I'm trying to process an image that comes from a JpegImageCallback like this

    mContentView.setOnClickListener(new View.OnClickListener() {

        @Override

        public void onClick(View view) {

            mContentView.getCamera().setPreviewCallback(null);

            mContentView.getCamera().takePicture(null, null, new JpegImageCallback());

        }

    });

The JpegImageCallback looks like this

    class JpegImageCallback implements Camera.PictureCallback {



    @Override

    public void onPictureTaken(byte data, Camera camera) {

        Log.d(TAG, "onPictureTaken: I am here! data.length=" + data.length);



        Camera.Parameters params = camera.getParameters();

        int fw = params.getPictureSize().width;

        int fh = params.getPictureSize().height;



        Log.d(TAG, "onPictureTaken: PictureFormat: " + params.getPictureFormat()); /* ImageFormat.NV21 */

        Log.d(TAG, "onPictureTaken: PreviewFormat: " + params.getPreviewFormat()); /* ImageFormat.NV21 */



        /* conversion data to Mat */

        Mat mYuvFrameData = new Mat(fh + (fh/2), fw, CvType.CV_8UC1);

        mYuvFrameData.put(0, 0, data);

        Mat rgbImage = new Mat();

        Imgproc.cvtColor(mYuvFrameData, rgbImage, Imgproc.COLOR_YUV2RGBA_NV21, 4);

        Mat gryImage = mYuvFrameData.submat(0, fh, 0, fw);

    }

}

The conversion from data to org.opencv.core.Mat is copied from org.opencv.android.JavaCameraView. It works totally fine when the data comes in onPreviewFrame(byte frame, Camera camera) in a Camera.PreviewCallback. But in a Camera.PictureCallbacklike above I get the image wrong.

After the image is taken I display it in a ResultActivity, see below: left is from preview and correct, right is from picture and wrong (green).

I already changed the image format to be the same in preview and picture (ImageFormat.NV21), but that didn't make a difference. The image format for the picture is ImageFormat.JPEG if I don't change it.

So the question is: How do I convert data to Mat to get a correct Image in onPictureTaken like in onPreviewFrame?

Thanks for any ideas!

Edit:
I dont't want to save the image to disk and I don't want to convert it to a bitmap.

This works:

        Mat mat = new Mat(new Size(fw, fh), CvType.CV_8U);

        mat.put(0, 0, data);



        Mat rgbImage = Imgcodecs.imdecode(mat, Imgcodecs.CV_LOAD_IMAGE_UNCHANGED);

        Mat gryImage = new Mat();

        Imgproc.cvtColor(rgbImage, gryImage, Imgproc.COLOR_RGB2GRAY);

Found it here: How to retrieve a new picture taken by the camera as OpenCV Mat on Android?

Imgcodecs.imdecode does all the magic!

There is no need to change the image format, by the way.