Why selfies? That’s a gimmick. (Still, go ahead: send a snapshot to MemoriesInDNA.com and it may be turned into DNA.) But with the 10,000 images, it will encode into DNA a kind of picture database that it will use to develop new search techniques.
DNA image search: Microsoft aims to search for and classify images while they’re in DNA form. That, it says, is possible because certain DNA letters stick to others: a search query for “red car” coded into DNA should stick to bits of DNA that contains such an image. But it still needs to do that bit.