Friday, January 9, 2009
An interesting case
An interesting case that I've been working in private practice on focusses on the authenticity of certain photos posted to the popular photo sharing site Flickr.
A hex dump of the image revealed that it had been edited both in Picasa 3 as well as Photoshop. So I tried to see how this information trail ends up in the image - using my own images.
The first capture of the hex is from a photo taken by me with my Fuji FinePix s6000fd and edited last year with Photoshop CS3 for Windows. I opened this image in Picasa 3 and applied a little brightening to the image and saved it with a different file name. Then I looked the hex dump of this new image. The camera info is still there, along with the original date of capture ... but the Photoshop info has been replaced by Picasa. Notice that on the bottom of the shot, there still remains a mention of Photoshop. Aside from the difference in camera and date, this second hex dump is formatted similar to the questioned photo, with the Picasa reference on the top and the Photoshop reference on the bottom.
As a control, I took a new shot and used Picasa 3 to move the image from my camera to my computer (normally, I would use Lightroom 2). Acquiring the image in this way, the hex had no reference to Adobe in the questioned area of the hex info.
This is an interesting case with more than just the hex information that's suspicious. I'll be reporting more in the near future.