Earlier quoted context omitted.
> I really want to emphasize how insane this situation is, because I think most tech people won’t realize what’s happening unless it’s pointed out. Count me in. If you asked me about the OCR itself, I'd probably say "yeah, it's mostly been solved for a good decade for print books and articles, but it's unreliable enough". I somehow never considered OCR might have gone better - possibly because my main exposure was th…
There is a chance that your photos are being backed up by some cloud service and being removed from your gallery. The most likely suspect is Google Photos. Note that Google photos not only OCRs, but it also does a visual search of objects, faces, scenery etc. and is extremely powerful.
I have Google Photos upload and backup both disabled.
But then, I'm pretty sure either Google or Samsung SMS app had a "feature" to automatically delete old messages (for a definition of "old" that was neither specified, nor configurable), and it defaulted to ON on my current phone, likely costing me significant chunk of my message archive (that I dutifully transferred over from the previous phone) before I accidentally found and disabled the switch.
So yeah, could be Google Photos deleting it. Or someone else. I don't trust Android as a platform anymore.
BTW. about this "delete old messages" "feature" - most likely this was implemented for performance reasons. But the thing is, you're unlikely to send or receive enough SMS in your whole life for it to take a noticeable amount of space. The irony here is, I do remember a case where the messaging app would become slow and laggy if you had enough texts stored on the phone - but that was solely because someone implemented the message list as a linked list, thus adding a O(N) multiplier to many GUI operations.