Camera takePicture does not always do jpeg callback depending on picture size

Question

I am with stuck problem where camera.takePicture() jpeg callback gets less frequently called where desired picture size is higher. E.g. it always succeedes with 640x480, but only works on 5% to 40% of cases with minor parameter tweaks with 3264x2448 resolution. Relevant code:

public void foo(View view) {
    Camera.PictureCallback jpegCallback = new Camera.PictureCallback(){
        @Override
        public void onPictureTaken(byte[] bytes, Camera camera) {
            camera.release();
            Toast.makeText(SurvCamActivity.getInstance(), "jpeg callback", Toast.LENGTH_SHORT).show();
        }
    };
    //Gets desired resolution
    SpinnerResolution res = getSelectedSpinnerResolution();
    Camera camera = getCameraInstance();
    try {
        Camera.Parameters params = camera.getParameters();
        params.setPictureSize(res.width, res.height);
        camera.setParameters(params);
        camera.setPreviewTexture(new SurfaceTexture(R.layout.fragment_preview));
        camera.startPreview();
        camera.takePicture(null, null, jpegCallback);
    } catch (IOException e) {
        e.printStackTrace();
    } 
}

Now odd thing is, if I add breakpoint to camera.takePicture() and simply resume execution once thread reaches there it always calls the jpeg callback. When I added Thread.sleep(700) after the camera.takePicture() it also started consistently doing the callbacks. Any ideas? Tested on Nexus 4.

Answer 1

EDIT: Turns out the camera object might have got garbage collected. I created static reference to it and now it works without problems.

Answer 2

You cannot call camera.takePicture() again before jpegCallback.onPictureTaken() is started, so you need to throttle the button.onClick(). You can probably reduce he lag if you keep the camera in preview mode all the time.