PhotoDNA is the gold standard for this. I tried to get access to this via the NCMEC to use with Neocities, but the process was, frankly, very convoluted. I signed at least 10 forms and still didn't end up getting what I needed.
I'm happy that Microsoft is providing this as a free service. It's going to be a lot less painful for me to use it than to figure out how to run my own (or in this case, figure out how to even get it).
I'm happy that Microsoft is providing this as a free service. It's going to be a lot less painful for me to use it than to figure out how to run my own (or in this case, figure out how to even get it).