Photo forensic is a branch of forensic engineering. The forensic operation might be comprised of the following
1. Digital Image pixel analysis
Forged digital image has a sudden changes on the pixel or some pixels spread in rather wide range.
2. Format based analysis
This methods analyse compress and de-compression of digital image.
3. Camera based probe
Each and every camera has its unique patten on the images processing.
You may check your images at the following site.