You COULD use the Unix commands 'cksum' or 'sum' or even 'md5'. This is a byte for byte comparison producing a CRC (Cyclic Redundancy Check - for the sum commands) or a 'message-digest fingerprint or checksum' for a file. cksum, sum -- display file checksums and block counts md5 -- calculate a message-digest fingerprint (checksum) for a file However, this will only work for LIKE TYPES of files. In other words, if AN image is stored in two different files of the same time (e.g. jpg) and the image is EXACTLY the same. If, for instance you crop one, even minutely and save it, then it becomes an entirely different image (file) and the checksums for each will be different - even though they may both be visually SIMILAR. Another thing to consider is what if the same image is stored in two different formats (e.g. 1 TIFF and 1 JPG). In this case the visual IMAGE is a duplicate but to a computer it's two different images. If you are trying to find VISUALLY duplicate images... you might want to check here: http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel5/4036509/4036510/04036609.pdf? temp=x You have to PURCHASE the document referenced by the link, and I would guess that it's copyright protected (most likely internationally since the authors are Canadian). Otherwise, just 'Google' "duplicate image" there are TONS of links for this. No matter which method you use, what you'll end up doing is storing some sort of hash/checksum in a database and then looking for duplicates... OR disallowing duplicate image store if that's your end goal. Good Luck. Larr. --- In php-objects@xxxxxxxxxxxxxxx, "aslam doctor" <aslam.doctor@...> wrote: > > Hello friends, > I m working on a very interesting concept, for that i want to create one > Image compare System, in which 2 images are compared. > > Is it possible to do using? any reference site for that?? > > Plz reply. Thanks in advance > > -- > A.M.Doctor > > > [Non-text portions of this message have been removed] >
