Canvas canvas = new Canvas(drawingBitmap);
Paint paint = new Paint();
canvas.drawBitmap(sourceBitmap, 0, 0, paint);
paint.setXfermode(new PorterDuffXfermode (android.graphics.PorterDuff.Mode.SCREEN)); // способ смешивания
canvas.drawBitmap(destinationBitmap, 0, 0, paint);