Solved

Identical photos?

Posted on 2006-11-09
3
434 Views
Last Modified: 2013-11-19
I need a program that will tell me if two jpg photos are identical, and if not, how many pixels are different, and where those pixels are located.  I assume that a program that could do this could work with various resolutions of jpg.
0
Comment
Question by:hcsorensen
  • 2
3 Comments
 
LVL 38

Accepted Solution

by:
lherrou earned 500 total points
ID: 17914956
hcsorensen,

If you're saying, you want a program which can eyeball two pictures of different resolution, and tell if they are the same photo (as can easily be done by the human observer), you aren't going to find that (maybe contact the DoD or CIA, they are known to work on these kinds of issues). If you need a program to evaluate two photos and review amount of total differences you should take a look at the ImageMagick "compare" command (http://www.imagemagick.org/script/compare.php). This command returns qualitative results and can also return a "map of changed pixels", so if you are comparing amount of change in different forms of image alterations (compression, sharpening, etc), it can give you a numeric value and also a picture of the density of the changes in the image.

Cheers,
LHerrou
0
 

Author Comment

by:hcsorensen
ID: 17917199
Many thanks.  Right on target.  I think this solves my problem.
0
 
LVL 38

Expert Comment

by:lherrou
ID: 17917856
Great. I hope it does the job. And thanks for the points and the "A".

BTW, here's a site using the compare command to show differences between compression in JPG and PNG file formats, it illustrates what can be done: http://www.fractalus.com/info/png-jpeg.htm
0

Featured Post

NAS Cloud Backup Strategies

This article explains backup scenarios when using network storage. We review the so-called “3-2-1 strategy” and summarize the methods you can use to send NAS data to the cloud

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
header for blue logo 6 233
Restoring corrupted jpg and mp4 files 11 92
Need to create an automated "sketch" of a photo 3 76
MS PAint how to type 14 143
Many programs have tried to outwit PowerPoint in terms of technology and skill. These programs, however, still lack several characteristics that PowerPoint has possessed from the start. Here's why PowerPoint replacements won't entirely work for desi…
Technology opened people to different means of presenting information, but PowerPoint remains to be above competition. Know why PPT still works today.
In this Micro Tutorial viewers will learn the basic shortcuts and functions in InDesign.
Learn how to create interesting presentations by including videos to keep your audience engaged using Prezi. Select "Insert" from the top menu in your Prezi editor: Select "YouTube Video": Paste the video URL into the prompt: "Select "Insert":…

821 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question