Convert Image to Negative in Android

Convert Image to Negative with this method

public Bitmap ConvertToNegative(Bitmap sampleBitmap){
ColorMatrix negativeMatrix =new ColorMatrix();
float[] negMat={-1, 0, 0, 0, 255, 0, -1, 0, 0, 255, 0, 0, -1, 0, 255, 0, 0, 0, 1, 0 };
negativeMatrix.set(negMat);
final ColorMatrixColorFilter colorFilter= new ColorMatrixColorFilter(negativeMatrix);
Bitmap rBitmap = sampleBitmap.copy(Bitmap.Config.ARGB_8888, true);
Paint paint=new Paint();
paint.setColorFilter(colorFilter);
Canvas myCanvas =new Canvas(rBitmap);
myCanvas.drawBitmap(rBitmap, 0, 0, paint);
return rBitmap;
}