2007/10/15, David W. Tamkin <[EMAIL PROTECTED]>: > > Harry, > > > so i was wondering what advantages it could give me to make a ffp > > file, because there is already a internally stored md5 checksum on the > > decoded audio data inside the flac file? > > Testing the .flac file against its internally stored fingerprint lets > you know that you have a properly encoded .flac file of *something*. If > you also certify that internally stored fingerprint against a list of > correct fingerprints in another file, then you know you have a properly > encoded .flac file of the *right* audio, and that the person who sent > you the .flac files didn't accidentally provide a wrong file instead. > > Yes, a miscreant who would intentionally switch .flac files on you would > also alter the .ffp file to show the fingerprint of the wrong file > instead of the right one, but that could not happen by accident. > Sending a set of .flac files with an .ffp file says, "I wouldn't > deliberately deceive you"; sending a set of .flac files with no > checksums at all says "I never make mistakes." There are people whom > I'd trust not to deceive me deliberately but nobody from whom I'd accept > a claim of infallibility. > > Moreover, if a set of .flac files is being shared, a copy of the > fingerprints can be kept at a URL distributed with them, so that > everyone receiving them can make sure that the fingerprints of the files > (s)he gets match those of the original set.
yes, I all understand that, but I mean advantages when you don't send those files over the internet. So just encode them and burn them to a cd. Or is a ffp file only useful when you want to upload those files? > i was also wondering how files encoded by using the new > > --keep-existing-metadata option are verified when using -verify. Is > > there a separate internally stored md5 for metadata next to the md5 > > for decoded audio data or how is everything verified? > > Until we hear from someone who knows, I'd venture to say that --verify > does just what it always did, and it has nothing to do with existing > metadata in the uncompressed input. As it encodes each segment of the > audio, it re-decodes it and compare the result to the original input. but how can you verify the metadata of the input files then if there is no check for this? > Is making a ffp file for such files also possible for the non-audio > > data (so all metadata)? > > No, fingerprints are defined only for audio. same question as above > i was also wondering if there exists a GUI program for win32 to verify > > flac files using a ffp file (so not md5check.exe) > > Yes: Trader's Little Helper at http://thor.prohosting.com/roh0205/. thx, it's exactly what i'm looking for! unfortunately the file is offline, can you maybe email the file to me if you still have it?
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