Oh. I remember reading some vision paper and in the supplement materials there've been a couple of videos with letters moving. Doubt, I'll be able to find it that easily.
Should be relatively easy to code with any library that can draw a text on a bitmap. Like PIL, matplotlib, etc. Use ffmpeg to make a video out of frames.
1. draw letters (just black/white) masks;
2. fill letters with noise;
4. fill background with noise;
5. copy letters using a mask onto background, using X,Y as loc;
6. add a little bit of new noise to letters;
8. modify X,Y coordinates (move letters SLIGHTLY);
9. go to step 4.
I made a proof-of-concept implementation and, well, it works, but I suspect they're too difficult for many people. They can be made easier by emphasizing one of the colors in the letters, but that opens them up to more traditional attacks.
Should be relatively easy to code with any library that can draw a text on a bitmap. Like PIL, matplotlib, etc. Use ffmpeg to make a video out of frames.
1. draw letters (just black/white) masks; 2. fill letters with noise; 4. fill background with noise; 5. copy letters using a mask onto background, using X,Y as loc; 6. add a little bit of new noise to letters; 8. modify X,Y coordinates (move letters SLIGHTLY); 9. go to step 4.