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Image Error Level Analyser

Submit an image url for error level analysis:

  • Jpeg files only please.
  • If you need an image host, we recommend imgur.com
  • ELA implementation written by pgr.

Example

Error level analysis shows differing error levels throughout this image, strongly suggesting some form of digital manipulation. Areas to note are the lips and shirt, as well as the eyes. All are at significantly different error levels than their surroundings. Presumably, colours have been altered and areas brightened.

Mouse over for ELA image

Image from www.valleygirl.com.au

Explanation

“Error level analysis (ELA) works by intentionally resaving the image at a known error rate, such as 95%, and then computing the difference between the images. If there is virtually no change, then the cell has reached its local minima for error at that quality level. However, if there is a large amount of change, then the pixels are not at their local minima and are effectively original.”

-Neal Krawetz, Ph.D. http://www.hackerfactor.com

This implemenation makes use of the Python Image Library, and libjpeg (v6.2.0-882.2). ELA is carried out at 95%. Resulting ELA images have had their brightness enhanced to further seperate differences out.

Built over a lazy weekend with django. Inspired by Neal Krawetz and his image forensic work.

Contact me at p.ringwood@gmail.com.

Need a website built?, again, contact me at p.ringwood@gmail.com.