I take screenshots of the application and try to determine if there was an exact image before. I am looking to define trivial changes as different - for example. if the image has text, and spelling changes that are considered inconsistencies.
I successfully used the MD5 hash of the contents of the image on the screen to search the database for known images and discovered if this had happened before.
Now I have ported it to another machine, and despite my attempts to accurately match the configurations, I always get slightly different images for the old machine. When I say different, changes are minutes — if I blow up old and new images and shake between them, I don’t see any difference! However, the ImageMagick compare command can see a small number of pixels that are different from each other.
So my MD5 hashes no longer match. Instead of a simple MD5 hash, I need an image hash .
Carrying out my research, I found that most image hashes try to be quite generous - they accept altered, transformed and watermarks with corresponding false-positive matches. I want the hash image to be much more strict - only changes that are minor color changes are possible.
Can anyone recommend a library or image hashing algorithm? (Not an application, such as dupdetector ).
Remember: my requirements differ from many similar questions in that I do not want a liberal algorithm, for example, to shrink or pHash , and I do not need a comparison tool, for example, structural similarity or Compare ImageMagick .
I want a hash that makes very similar images to give the same hash value. Is it possible?
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