This is another image, but the details is white here, is that what I need.
CodePudding user response：
If you are using a 8bit bitmap image it is a simple operation of doing
var v = byte.MaxValue - myBitmap.GetPixel(x, y).R;
myBitmap.SetPixel(x,y, Color.FromArgb(v, v, v)
Or see fast work with bitmaps to access the pixel values directly.
