private void CompareInternal(Bitmap one, Bitmap two) { if (one.Width != two.Width || one.Height != two.Height) { //Sizes do not match return; } var lockedOne = new LockBitmap(one); var lockedTwo = new LockBitmap(two); var numberOfDifferentPixels = 0; for (int i = 0; i < one.Width; i++) for (int j = 0; j < one.Height; j++) { if (lockedOne.GetPixel(i, j) != lockedTwo.GetPixel(i, j)) { numberOfDifferentPixels++; } } Debug.WriteLine("Different pixels: " + numberOfDifferentPixels); }