Abstract: Geometric transformations such as scaling or rotation are common tools employed by forgery creators. These procedures are typically based on a resampling and interpolation step. The interpolation process brings specific periodic properties into the image. In this paper, we show how to detect these properties. Our aim is to detect all possible geometric transformations in the image being investigated. Furthermore, as the proposed method, as well as other existing detectors, is sensitive to noise, we also briefly show a simple method capable of detecting image noise inconsistencies. Noise is a common tool used to conceal the traces of tampering.

  author       = {Babak Mahdian and Stanislav Saic},
  url          = {http://library.utia.cas.cz/separaty/2009/ZOI/saic-detection and description of geometrically transformed digital images.pdf},
  pages        = {72540J},
  volume       = {7254},
  title        = {Detection and description of geometrically transformed digital images},
  editor       = {Edward J. Delp and  Jana Dittmann and Nasir D. Memon and Ping Wah Wong},
  year         = {2009},
  keywords     = {Image Forensics; Tamper Detection},
  booktitle    = {Proceedings of SPIE-IS\&T Electronic Imaging: Media Forensics and Security XI},