[Five]

since 2005 we have .st5 checksums available from .shn sets using Trader's Little Helper (TLH), which can be compared for perfection against Flac Fingerprint (.ffp). Also noteworthy is that double-clicking an ffp file with TLH installed will compare and run self-test. Using Flac Frontend, you have to hit 'test' and 'fingerprint' then compare visually the checksums with other known sets to identify it. TLH modern way is great. Also, etree's current 'Flac Fingerprint' page is spot-on as of this writing, go look it up.

Blast from the past, showing some of the confusion upon the arrival of flac and understandable resistance of all the people who collected 10,000 GD/Phish shows in .shn format, using the poor standard of wholefile .md5 as opposed to current .ffp/.st5

keep in mind reading this that it is for the history, and also that .st5 we have been using since 2005 is the exact same checksums inside.

original etree wiki Flac Fingerprint page 2002-11-17
Thu, 02 Jan 2003 17:32:44 DianaHamilton [lma]

Originally Posted by etree.org

Flac Fingerprint

A FLAC Fingerprint is a small text file (ffp.txt) that contains the filename and a printout of checksum information for one or more .flac files. The fingerprint is analogous to yet somewhat different from the .md5 files for used for Shorten (.shn):

• Unlike an .md5 file, the FLAC Fingerprint ffp.txt file itself is not actually used in performing integrity checks on .flac files. Instead, FLAC automatically verifies each file against an internal checksum when you decompress.
  
  
• The ffp.txt information is used to visually compare different .flac filesets for lineage purposes. Reference fingerprints can be listed in the ShnDatabase. In a similar way, the ShnDatabase lists .md5s as "fingerprints" for .shn filesets. In both cases, the [Internet Archive] also uses the fingerprints stored in the ShnDatabase to speed up their archiving of the music. So, it makes good sense to include a FLAC fingerprint file with each .flac seed.
  
  
• A FLAC Fingerprint is generated only for the audio data portion of the file. This gives a truer reference point- just for the most important part of the file. In contrast, .md5s are generated against whole files, including extraneous or variable data (such as the seek tables on .shns).
  
  
• SPECIAL NOTE ABOUT .MD5 FILES AND FLAC: It is a VERY bad idea to make an .md5 checksum file for a .flac fileset! Under FLAC, you can change the compression ratio and add/remove meta data to .flac files without changing the actual audio. The audio may be identical, but the extra data will completely change the .md5 checksum. This would cause major confusion when trying to compare the fileset against others in a database (similar to the current situation with nonseeking vs. seek-appended .shn files).
  
  
• Repeat: Never make .md5 checksum files of .flac files. For .flac files, .md5s are useless as reference tools. Doing so will only cause unnecessary chaos and confusion.

See also: FLAC, FlacFrontend, SeedingGuidelines
This Page Last Changed: Nov 7, 2002 14:29:11