Say you write me a cheque for $50 and I photoshop that into $500, how can they detect that?
I did not touch the serial number and, as the summary suggests, the photo was taken with a lousy cell-phone camera.
If they have a minimal requirement for picture quality, the system will most likely reject a lot of deposit attempts (motion-blur, out of focus, low resolution, etc..)
Doesn't really seem worth the trouble.
At the source of every error which is blamed on the computer you will find at least two human errors, including the error of blaming it on the computer.