Very interesting approach. I have worked with image feature extraction in the past. Although using DCT coefficients has been used as a way to analyze texture f

Very interesting approach. I have worked with image feature extraction in the past. Although using DCT coefficients has been used as a way to analyze texture features, the idea idea of generating the hash (step 5) seems to be new. I am curious however on why you are discarding color information. Usually for reverse image search this kind of information can be quite useful.