how to merge to two bitmap one over another

you can combine two bitmaps like this

public static Bitmap overlay(Bitmap bmp1, Bitmap bmp2) {
    Bitmap bmOverlay = Bitmap.createBitmap(bmp1.getWidth(), bmp1.getHeight(), bmp1.getConfig());
    Canvas canvas = new Canvas(bmOverlay);
    canvas.drawBitmap(bmp1, new Matrix(), null);
    canvas.drawBitmap(bmp2, 0, 0, null);
    bmp1.recycle();
    bmp2.recycle();
    return bmOverlay;
}