Click and hold B to show the character. Click N to change the character. Click space or click to start time warp. Click Direction to change the direction of the scan.
I did not to any of the code, @1080GBA did some and @griffpatch did all of the rest. Special Notice - This project does not make use of cloud data, so you can be quite sure it is not sharing your image in any way. If you are ever unsure, then just look below the project on this screen and look if it says "Cloud Variables" next to "Video Sensing". If not, then you are quite safe! If it does, then please be careful!