Writing algorithms for pixellating images to required granularity is a specialized skill. However, using a library that does that, is a much more common skill.

Writing algorithms for pixellating images to required granularity is a specialized skill. However, using a library that does that, is a much more common skill. I wouldn't be surprised if, in the future, sculptures will also be CNC machine assisted. It is possible, now , to use a CNC machine to rough cut sculptures and then fine cut them with hand.