Just a note, this is not something i would simply trust. Phone camera can easily make a blurred or unfocused image. If you see the whole picture in its entirety to verify you would then be able to remember the number and make the "game" redundant.masterbot wrote:* the stored secret can be a simple text or a picture (usually a picture of combination lock)
So one way i've thought an image could be verified is by fragmenting it in tiny pieces, set them in random order and rotations. Then show something like 20% of the fragments to the user for piece of mind. There would be a button to show a different random set in again different order and rotations.
Even better if you were able to use image recognition view only the area of the numbers, that then sliced instead of all outside of it. Because it would show so tiny fragments of the numbers it would be harder to determine what number a slice is from.
... Alternatively this doesn't need any image recognition, just first a blurred black&white version of the image from which user can roughly crop the area of the numbers himself.