While this article is on sound fingerprinting it does talk about image fingerprinting, the algorithm finds "significant" points in the image and as such can still work because it looks at their positions respective to each other, which will still hold after scaling or rotating. And cropping is likely to remove content lacking such features, so it can handle that as well.

https://emysound.com/blog/open-source/2020/06/12/how-audio-f...