Is there such thing as a 'soft checksum' tool?

[Mel Flynn]

On Monday 07 September 2009 05:09:53 Michael David Crawford wrote:
> > M> I'm looking for a pseudo-checksum tool for use with cataloging images.
>
> I've seen such tools advertised, but they were proprietary products and
> only worked on windows.
>
> One way you could approach it might be to use a blur filter to blur each
> of your images, and then to compare the blurred images.  Small
> differences in individual pixels would be blurred away.

Did you guys miss Charlie Kester's message? And the above does not work, 
because of compression anyway. Just because you think of an image as a bitmap, 
does not mean it's stored as such.
-- 
Mel