Kamera Frame manipulieren ...

public void onFrame(final ByteBuffer frame) {
			frame.clear();
			synchronized (bitmap) {
				bitmap.copyPixelsFromBuffer(frame);
				Canvas c = new Canvas(bitmap);
				Paint p = new Paint();
				// text color - #3D3D3D
				p.setColor(Color.rgb(61, 61, 61));
				// text size in pixels
//				p.setTextSize((int) (14 * scale));
				p.setTextSize((int) (14 * 10));
				// text shadow
				p.setShadowLayer(1f, 0f, 1f, Color.WHITE);
				c.drawText("Hello Nobody", 30, 210, p);
				ByteArrayOutputStream stream = new ByteArrayOutputStream();
				bitmap.compress(Bitmap.CompressFormat.PNG, 100, stream);
				frame.get(stream.toByteArray(), 0, stream.toByteArray().length);
			}
		}

public void setFrameCallback(final IFrameCallback callback, final int pixelFormat) {
    if (mNativePtr != 0) {
        nativeSetFrameCallback(mNativePtr, callback, pixelFormat);
    }
}


private static final native int nativeSetFrameCallback(final long mNativePtr, final IFrameCallback callback, final int pixelFormat);


public interface IFrameCallback {
	/**
	 * This method is called from native library via JNI on the same thread as UVCCamera#startCapture.
	 * You can use both UVCCamera#startCapture and #setFrameCallback
	 * but it is better to use either for better performance.
	 * You can also pass pixel format type to UVCCamera#setFrameCallback for this method.
	 * Some frames may drops if this method takes a time.
	 * When you use some color format like NV21, this library never execute color space conversion,
	 * just execute pixel format conversion. If you want to get same result as on screen, please try to
	 * consider to get images via texture(SurfaceTexture) and read pixel buffer from it using OpenGL|ES2/3
	 * instead of using IFrameCallback(this way is much efficient in most case than using IFrameCallback).
	 * @param frame this is direct ByteBuffer from JNI layer and you should handle it's byte order and limitation.
	 */
	public void onFrame(ByteBuffer frame);
}