[ale] image diff utility?

[James P. Kinney III]

On Thu, 2004-06-03 at 20:15, Dow Hurst wrote:
> Maybe the ImageMagick "identify" command could be a starting place.  The cmp 
> will compare files but identify seems to be more appropriate.  Use the 
> -verbose option for lots of info.  Maybe a Perl wrapper that used identify? 
> Just guessing here,
> Dow
> 
Wow!! Identify is a really useful tool. I use "convert" often but I
never looked at what identify could do. The list of colors and their
prevalence has a lot of possibilities for image analysis. It sure beats
the old adaptive-subtraction methods I had to muddle with in grad
school.

> 
> Christopher Bergeron wrote:
> > Does anyone know of any command line utilities that can compare two 
> > images (jpg, pngs, whatever), and if they visually differ by a set 
> > threshold they will output a true or false flag?
> > 
> > I've seen this done in big bloated security applications, but I'm 
> > looking for a simple command line utility or method of doing something 
> > like this:
> > 
> > if (image1.png) is more than n percent different from (image2.png), exit 
> > with a true; if not, exit with a false
> > 
> > Heck, I don't even need to have an adjustable threshold; I just need to 
> > know if 2 images are significantly different.  Does anyone have any 
> > ideas on how I could accomplish this?
> > 
> > Thanks in advance!
> > -CB
> > _______________________________________________
> > Ale mailing list
> > Ale at ale.org
> > http://www.ale.org/mailman/listinfo/ale
> > 
-- 
James P. Kinney III          \Changing the mobile computing world/
CEO & Director of Engineering \          one Linux user         /
Local Net Solutions,LLC        \           at a time.          /
770-493-8244                    \.___________________________./
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GPG ID: 829C6CA7 James P. Kinney III (M.S. Physics)
<jkinney at localnetsolutions.com>
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