Android ImageReader.acquireLatestImage returns invalid JPG

Question

I am using Android ImageReader class to receive Bitmaps from MediaProjection.createVirtualDisplay method.

My code so far looks like this:

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Answer 1

Fo those of you looking for the easiest way to capture from ImageReader to a JPG (be it bytes on disk or in memory) It's actually quite simple.

Given an ImageReader, set it to ImageFormat.JPEG:

ImageReader imageReader = ImageReader.newInstance(largest.getWidth(), largest.getHeight(), imageFormat, 1);

Then in the CameraCaptureSession.StateCallback:

captureSession.capture(captureRequest, new CameraCaptureSession.CaptureCallback() {
    @Override
    public void onCaptureCompleted(@NonNull CameraCaptureSession session, @NonNull CaptureRequest request, @NonNull TotalCaptureResult result) {
        super.onCaptureCompleted(session, request, result);             
        Image image = imageReader.acquireLatestImage();
        final Image.Plane[] planes = image.getPlanes();
        final ByteBuffer buffer = planes[0].getBuffer();
        buffer.rewind();
        byte[] bytes = new byte[buffer.remaining()];
        buffer.get(bytes);

    }
}

Then you have bytes which you can do anything with. Send them over a socket, to a file, hash them, etc.