Okay.. I love flac but just had a rather serious failure that really shakes my confidence. It resulted in the near loss of a master audio recording. Fortunately, I have a backup. Though there may have been other cases where I have lost original material because I have been compressing a lot of originals and deleting them after doing a 'flac -t' on them. Basically, flac failed with a 'warning' but still created flac archives which tested ok. Here's the scoop: % flac *wav flac 1.1.1, Copyright (C) 2000,2001,2002,2003,2004 Josh Coalson flac comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it under certain conditions. Type `flac' for details. options: -P 4096 -b 4608 -m -l 8 -q 0 -r 3,3 umb.1.wav: WARNING: skipping unknown sub-chunk 'p9' umb.2.wav: WARNING: skipping unknown sub-chunk 'c=?' % flac -t *flac flac 1.1.1, Copyright (C) 2000,2001,2002,2003,2004 Josh Coalson flac comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to redistribute it under certain conditions. Type `flac' for details. umb.1.flac: ok umb.2.flac: ok % ls -lt total 3105736 -r--r--r-- 1 root root 4186 Jun 5 00:43 umb.2.flac -r--r--r-- 1 b b 1933467692 Jun 5 00:43 umb.2.wav -r--r--r-- 1 root root 4186 Jun 4 22:37 umb.1.flac -r--r--r-- 1 b b 1243668524 Jun 4 22:37 umb.1.wav % file * umb.1.flac: FLAC audio bitstream data, 24 bit, stereo, 44.1 kHz, length unknown umb.1.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 24 bit, stereo 44100 Hz umb.2.flac: FLAC audio bitstream data, 24 bit, stereo, 44.1 kHz, length unknown umb.2.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 24 bit, stereo 44100 Hz % flac -v flac 1.1.1 % uname -a Linux foobar 2.6.7-gentoo-r11 #12 Fri Aug 12 19:40:17 EDT 2005 x86_64 AMD Athlon(tm) 64 Processor 3000+ AuthenticAMD GNU/Linux My guess is that in this case, the wav file header may not correctly reflect the length of the wav file. I would think that flac could be coded to handle these cases correctly. Thank you! Brian
Sounds like that could easily be fixed by adding a command line flag that would delete the output file if flac exits on error. That could also be easily scripted. TJ Free Lunch wrote:>Basically, flac failed with a 'warning' but still created flac >archives which tested ok. >
can you file a bug on sourceforge: http://sourceforge.net/tracker/?group_id=13478&atid=113478 and attach the first 100k of each file? it will help to debug since I don't have any wave files that cause this behavior. Josh --- Free Lunch <freelunch@gmail.com> wrote:> Okay.. I love flac but just had a rather serious failure that really > shakes my confidence. It resulted in the near loss of a master audio > recording. Fortunately, I have a backup. Though there may have been > other cases where I have lost original material because I have been > compressing a lot of originals and deleting them after doing a 'flac > -t' on them. > > Basically, flac failed with a 'warning' but still created flac > archives which tested ok. > > Here's the scoop: > > % flac *wav > > flac 1.1.1, Copyright (C) 2000,2001,2002,2003,2004 Josh Coalson > flac comes with ABSOLUTELY NO WARRANTY. This is free software, and > you are > welcome to redistribute it under certain conditions. Type `flac' for > details. > > options: -P 4096 -b 4608 -m -l 8 -q 0 -r 3,3 > umb.1.wav: WARNING: skipping unknown sub-chunk 'p9' > umb.2.wav: WARNING: skipping unknown sub-chunk 'c=?' > % flac -t *flac > > flac 1.1.1, Copyright (C) 2000,2001,2002,2003,2004 Josh Coalson > flac comes with ABSOLUTELY NO WARRANTY. This is free software, and > you are > welcome to redistribute it under certain conditions. Type `flac' for > details. > > umb.1.flac: ok > umb.2.flac: ok > % ls -lt > total 3105736 > -r--r--r-- 1 root root 4186 Jun 5 00:43 umb.2.flac > -r--r--r-- 1 b b 1933467692 Jun 5 00:43 umb.2.wav > -r--r--r-- 1 root root 4186 Jun 4 22:37 umb.1.flac > -r--r--r-- 1 b b 1243668524 Jun 4 22:37 umb.1.wav > > % file * > umb.1.flac: FLAC audio bitstream data, 24 bit, stereo, 44.1 kHz, > length unknown > umb.1.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 24 > bit, stereo 44100 Hz > umb.2.flac: FLAC audio bitstream data, 24 bit, stereo, 44.1 kHz, > length unknown > umb.2.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 24 > bit, stereo 44100 Hz > > > % flac -v > flac 1.1.1 > % uname -a > Linux foobar 2.6.7-gentoo-r11 #12 Fri Aug 12 19:40:17 EDT 2005 x86_64 > AMD Athlon(tm) 64 Processor 3000+ AuthenticAMD GNU/Linux > > > My guess is that in this case, the wav file header may not correctly > reflect the length of the wav file. I would think that flac could be > coded to handle these cases correctly.__________________________________ Yahoo! Mail - PC Magazine Editors' Choice 2005 http://mail.yahoo.com
Hi Josh, I have filed a bug and uploaded an example file. http://sourceforge.net/tracker/index.php?func=detail&aid=1293830&group_id=13478&atid=113478 Thank you! Brian On 9/16/05, Josh Coalson <xflac@yahoo.com> wrote:> can you file a bug on sourceforge: > > http://sourceforge.net/tracker/?group_id=13478&atid=113478 > > and attach the first 100k of each file? it will help to debug > since I don't have any wave files that cause this behavior. > > Josh > > --- Free Lunch <freelunch@gmail.com> wrote: > > Okay.. I love flac but just had a rather serious failure that really > > shakes my confidence. It resulted in the near loss of a master audio > > recording. Fortunately, I have a backup. Though there may have been > > other cases where I have lost original material because I have been > > compressing a lot of originals and deleting them after doing a 'flac > > -t' on them. > > > > Basically, flac failed with a 'warning' but still created flac > > archives which tested ok. > > > > Here's the scoop: > > > > % flac *wav > > > > flac 1.1.1, Copyright (C) 2000,2001,2002,2003,2004 Josh Coalson > > flac comes with ABSOLUTELY NO WARRANTY. This is free software, and > > you are > > welcome to redistribute it under certain conditions. Type `flac' for > > details. > > > > options: -P 4096 -b 4608 -m -l 8 -q 0 -r 3,3 > > umb.1.wav: WARNING: skipping unknown sub-chunk 'p9' > > umb.2.wav: WARNING: skipping unknown sub-chunk 'c=?' > > % flac -t *flac > > > > flac 1.1.1, Copyright (C) 2000,2001,2002,2003,2004 Josh Coalson > > flac comes with ABSOLUTELY NO WARRANTY. This is free software, and > > you are > > welcome to redistribute it under certain conditions. Type `flac' for > > details. > > > > umb.1.flac: ok > > umb.2.flac: ok > > % ls -lt > > total 3105736 > > -r--r--r-- 1 root root 4186 Jun 5 00:43 umb.2.flac > > -r--r--r-- 1 b b 1933467692 Jun 5 00:43 umb.2.wav > > -r--r--r-- 1 root root 4186 Jun 4 22:37 umb.1.flac > > -r--r--r-- 1 b b 1243668524 Jun 4 22:37 umb.1.wav > > > > % file * > > umb.1.flac: FLAC audio bitstream data, 24 bit, stereo, 44.1 kHz, > > length unknown > > umb.1.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 24 > > bit, stereo 44100 Hz > > umb.2.flac: FLAC audio bitstream data, 24 bit, stereo, 44.1 kHz, > > length unknown > > umb.2.wav: RIFF (little-endian) data, WAVE audio, Microsoft PCM, 24 > > bit, stereo 44100 Hz > > > > > > % flac -v > > flac 1.1.1 > > % uname -a > > Linux foobar 2.6.7-gentoo-r11 #12 Fri Aug 12 19:40:17 EDT 2005 x86_64 > > AMD Athlon(tm) 64 Processor 3000+ AuthenticAMD GNU/Linux > > > > > > My guess is that in this case, the wav file header may not correctly > > reflect the length of the wav file. I would think that flac could be > > coded to handle these cases correctly. > > > > > __________________________________ > Yahoo! Mail - PC Magazine Editors' Choice 2005 > http://mail.yahoo.com >