The point is that if you render the image in blocks of 16x16, there can only be 256 colors per block, so there can be as many colors in the image as there are p

The point is that if you render the image in blocks of 16x16, there can only be 256 colors per block, so there can be as many colors in the image as there are pixels. This 217*217 image has some duplicate pixels in the lower and higher values but gets fairly close to that maximum.