Hi,
If I move or copy a scrambled/fractured /broken photo to another folder, it becomes normal again.
This is most baffling and I also have never come across this issue before. It is almost like the original image file you are moving is corrupt in some way.
As a test take a screen shot, it should appear on the desktop now create a new desktop folder and drag it in that, what is the result broken or normal?
Also possibly try an SMC RESET
1) Shut down the computer.
2) Unplug the computer's power cord and all peripherals.
3) Press and hold the power button for 5 seconds.
4) Release the power button.
5) Attach the computers power cable.
6) Press the power button to turn on the computer.