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xiph / flac

Free Lossless Audio Codec
https://xiph.org/flac/
GNU Free Documentation License v1.3
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More info about `-t` argument #690

Closed MrComexs closed 2 months ago

MrComexs commented 2 months ago

Can you add more info of what -t does for flac cli tool. I very unsure what it does, my only guess is that it uses the MD5 value to recheck its self.

ktmf01 commented 2 months ago

See #668

MrComexs commented 2 months ago

Sorry about not searching the issues history, I do better next time.

I have two more question, be for I close the issue and they are, what should I expect the output of flac -t to be if it doesn't share the same MD5 sum and also do you have a link to some failed sample files so that I can see the output my self.

My last question is there any degradation in quality if I re-encode a flac file to a newer version. I have a test flac file that was written with libflac 1.1.0 and and a re-encoded version with libflac 1.4.3 and they both have the same MD5 sum so my guess is that there should be any degradation.

ktmf01 commented 2 months ago

I didn't meant to imply you should search the issue history, it is just that I recently answered the question, so referring to that answer is easier.

You can see an example output at #487. You can also see for yourself by simply trying to test a file that is not a FLAC file.

ktmf01 commented 2 months ago

Oh, I missed the edit. Here is an example of what happens when only the MD5 does not match:

$ flac -t testwrongMD5.flac

flac 1.4.3
Copyright (C) 2000-2009  Josh Coalson, 2011-2023  Xiph.Org Foundation
flac comes with ABSOLUTELY NO WARRANTY.  This is free software, and you are
welcome to redistribute it under certain conditions.  Type `flac' for details.

testwrongMD5.flac: ERROR, MD5 signature mismatch

Considering re-encoding, I know of no reason it could 'degrade' a file. However, when re-encoding, I recommend having a backup in case something unexpected happens like power failure or disk drive corruption.

MrComexs commented 2 months ago

I didn't meant to imply you should search the issue history, it is just that I recently answered the question, so referring to that answer is easier.

I know you didn't meant it that way but I felt like I have failed my self more than anything else.

Considering re-encoding, I know of no reason it could 'degrade' a file. However, when re-encoding, I recommend having a backup in case something unexpected happens like power failure or disk drive corruption.

I have a UPS and do plan to set up backups.

Thanks you for the help.