@Override
    public void release() {
        if (program != null) {
            program.delete();
        }
    }
Video processor that demonstrates how to overlay a bitmap on video output using a GL shader. The
bitmap is drawn using an Android {@link Canvas}.
dkplayer-sample/src/main/java/xyz/doikki/dkplayer/widget/render/gl/BitmapOverlayVideoProcessor.java