January 26, 2006
Image authenticity & Photoshop
The topic of verifying image authenticity, covered well in the NY Times article It May Look Authentic; Here’s How To Tell It Isn’t, continues to draw considerable attention. Photoshop of course gets pressed into duty on the falsification side, so Adobe staff have been fielding a number of press inquiries on this subject.
What may be less obvious is Adobe’s interest in the other side of the coin: image analysis & authentication. Last summer Dr. Hany Farid (mentioned in the Times article) spent his sabbatical from Dartmouth at Adobe, collaborating with the Advanced Technology Group on tools & techniques for detecting image manipulation. Photoshop is heavily used by a wide range of government & scientific bodies, aiding in everything from detecting forged checks (you’d be amazed what a few adjustment layers can reveal) to cleaning up satellite imagery to analyzing the Dead Sea Scrolls (more info on that soon). At the request of image retouchers who need to document their work, we added the Edit History Log, making it possible to store a textual log of edits done to an image (essential for reproducibility). Combined with the ability to embed raw files as Smart Objects, this feature makes it possible for a Photoshop document to contain essentially the negative, the print, and a printable record of edits performed.
For more on Dr. Farid’s research & tools, see his own site as well as this National Geographic article on detecting forged artwork. For more on Photoshop in scientific imaging, Adobe.com now details how scientific features have grown over the last few releases, alongside white papers on best practices.