Can anyone help me find an appropriate program for finding duplicate files, by their contents? I have a large number of photos, videos and audio, that over the years has been copied, moved, backed up, renamed, and re-encoded. I am now trying to remove all of this unnecessary duplication, as I think I can save a third of my current storage requirements. I want a program that will look at the video/photo and compare it to how other videos/photos look, and listen to the audio and compare it to how other audio files sound. I have been testing some software, so far I have tried: Duplicate Cleaner Pro (trial), which seems OK with audio, it only seems to compare the file size with videos, and it seems very hit and miss with photos. VisiPics seems to be OK with photos in the tests I have carried out. Do you guys know of any better programs? Free would be nice, but a small fee is acceptable.
I've had really good experience with similarity. It can be a little slow on really large collections, but it is very effective and accurate.
CCleaner, as well as being excellent for other things, has an good duplicate file finder built into it. It can match by name, size, modified date and content. EDIT: Reading OP again, I don't think it will perform the task you have in mind of comparing content in an intelligent way, rather than just comparing certain criteria. Computers generally aren't very good at that.
Apologies for the slow reply. Thank you IvanIvanovich, I am currently running a 2nd test on Similarity; it took me a while to figure out how to get it to compare videos, but in the first test it seemed to perform well. As you suggested it is taking ages, but I do appreciate the suggestion. From Googling, it does seem to me that the perfect program has not been written yet, or at least as far as I can tell. Whatever software I use I am still going to have to do a fair bit of manual checking and sifting. Wolfticket, CCleaner is not what I am looking for, it didn't find any duplicated in my small test, where I have setup duplicate files. Mr Evil, I have not tried Duplicate Picture Finder yet, but I will give it a go later.