The downside of it is the time to recalculate the hash. > > Quick test: md5 against a directory of NEF (nikon raw files) 135 seconds > for 721 files at about 30M each. > That's about 5 raw images at 30 M each. Suppose it's 1/5sec each. A > library of 100,000 images would take about 5 hours to extract checksums. > > If the unique ID is in the file, then the program only has to read part of > the file instead of all of it. >
The question is: how many times would you need to do a full recalculation? I would expect it only to be necessary in case of a catastrophic loss of all your data and having to recreate everything from zero, in which case I would guess losing 5h will be the smallest off your problems. In any case, you can save a minimum sidecar file including the hash together with your RAW in the backup. Or better yet, as Stefan suggested, include the hash on the filename. You could probably include only small part of it to avoid really long names, and then check the full hash to verify if you need it. Regards, Guillermo > ____________________________________________________________________________ darktable user mailing list to unsubscribe send a mail to [email protected]
