Get all pixels in circular image

You just need to know if a point x, y is in the circle or not, see below:

            GraphicsPath path = new GraphicsPath();
            path.AddEllipse(0, 0, 100, 100);
            Region region = new Region(path);
            if (region.IsVisible(10, 10))
            {
                //point 10, 10 is in the circular image
                //Bitmap.Getpixel(10,10).
            }