[Image-SIG] Comparing images

[Charlie Clark]

Am 01.04.2011, 20:30 Uhr, schrieb Charlie Clark  
<charlie.clark at clark-consulting.eu>:

> Hi,
>  I need to check lot of images to see if they have the right logo in  
> them. Fortunately I know the co-ordinates of where the logo in the image  
> should be but I'm not sure on the best way to compare a selection from  
> the image with a template. Currently I'm cropping the target image to  
> the right size and comparing it with ImageChops.difference() with the  
> template but I'm not sure how to interpret the results - I had hoped for  
> either a largely black or white image but I'm largely getting the  
> inverse of the logo.
>  Any tips?

Gah, search a little harder and I find, of course, that effbot has already  
answered this!

http://effbot.org/zone/pil-comparing-images.htm

Charlie
-- 
Charlie Clark
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