This challenges only the memory of the MCU, not the speed.
And it is a bit disappointing that they didn't finish the project by adding a 8x8 pixel camera and a 7-segment display.
replies(1):
https://learn.adafruit.com/adafruit-amg8833-8x8-thermal-came...
Mouse sensors are 8x8ish cameras, but very few of them(basically only the genuine HP/Agilent/Avago ADNS-2610 at bottom tier price) has raw image export feature, for some reason.
There are many other tiny potato camera parts on various markets, but most of them are missing datasheet && require complicated interfacing.
Overall it's actually not so trivial to get a small image sensor for hobby experiments.