Check a file

Chaine matches bytes, not pictures. A file that has been re-saved, resized, cropped or screenshotted has different bytes and will come back with no record — which is also the answer for almost every file in the world, because registering one is voluntary and almost nobody does it.

No record is not evidence about how a file was made or who made it. What a match buys is different in kind: it is not a judgement anybody made, it is an equality you can recompute yourself.