If you like to find out if a photo is original without any modification? now there is a software utility, named as JPEGsnoop that can help you to analyze the images if they have been edited before.

Every digital photo contains a plenty of hidden information and JPEGsnoop is designed to decode the inner details of JPEG and Motion AVI files. To determine whether a photo has been edited, JPEGsnoop uses the signature stored in its internal database for the camera model used to capture the image against a large number of compression signatures. If the compression signature matches Photoshop, then most likely the photo has been edited. Below are examples of the report analysis for original versus edited photo.

There are quite a lot of useful information that you can get from the analysis report such as settings that were used in the digital camera, quality and nature of the JPEG image compression used by the camera in saving file and many more. If you are camera enthusiast, this information is pretty important for you to know which camera models produce better JPEG images so that you can choose a right camera to suit to your preference.


One of the latest features in JPEGsnoop is an internal database that compares an image against a large number of compression signatures. JPEGsnoop reports what digital camera or software was likely used to generate the image. This is extremely useful in determining whether or not a photo has been edited / tampered in any way. If the compression signature matches Photoshop, then you can be pretty sure that the photo is no longer an original! This type of feature one of several sometimes referred to as Digital Image Ballistics / Forensics.

JPEGsnoop reports a huge amount of information, including: quantization table matrix (chrominance and luminance), chroma subsampling, estimates JPEG Quality setting, JPEG resolution settings, Huffman tables, EXIF metadata, Makernotes, RGB histograms, etc. Most of the JPEG JFIF markers are reported. In addition, you can enable a full huffman VLC decode, which will help those who are learning about JPEG compression and those who are writing a JPEG decoder.

Other potential uses: determine quality setting used in Photoshop Save As or Save for Web settings, increasing your scanner quality, locating recoverable images / videos, decoding AVI files, examining .THM files, JPEG EXIF thumbnails, extract embedded images in Adobe PDF documents, etc.
File Types Supported

JPEGsnoop will open and attempt to decode any file that contains an embedded JPEG image, such as:

  • .JPG - JPEG Still Photo
  • .THM - Thumbnail for RAW Photo / Movie Files
  • .AVI* - AVI Movies
  • .DNG - Digital Negative RAW Photo
  • .CRW, .CR2, .NEF, .ORF, .PEF - RAW Photo
  • .MOV* - QuickTime Movies, QTVR (Virtual Reality / 360 Panoramic)
  • .PDF - Adobe PDF Documents