File talk:Tim Berners-Lee - Today (ffmpeg FLAC in OGG).oga

Background

This audio file was created for a comparison with bare FLAC in the village pump 2014-01, and helped me to fix an error on Commons:Project_scope/Allowable_file_types a.s.a.p. –Be..anyone (talk) 15:37, 22 January 2014 (UTC)

Another version created with ffmpeg -err_detect aggressive -i source.flac -vn -a:c flac -sample_fmt s16 -f ogg output.oga, 3.12 MB instead of 7.33 MB after stripping 8 unused (?) of 24 bits. However, the commons transcoder does not more grok the duration (48s). –Be..anyone (talk) 17:46, 22 January 2014 (UTC)

Meanwhile McZusatz managed to create a working 16bit version, (apparently) applying ffmpeg -i input.flac -c:a copy -f ogg better.oga (3.45 MB instead of 7.33 MB). Be..anyone (talk) 17:50, 25 January 2014 (UTC)

I converted the audio to flac first and then copied the flac stream into the oga. --McZusatz (talk) 21:22, 25 January 2014 (UTC)

Okay, then the complete work flow was something like this:

1. BBC releases 7.33 MB .flac uploaded by Fantastic-life
2. Your command line applied on #1 would yield #2 .oga again
3. The first 16bit variant #3 was created with the command line in the description (-c:a flac-sampl_fmt s16 -f ogg)
4. You extracted the FLAC from #3 (.oga), applied your command line, and the current #3 has no duration issue

There might be two bugs, on the commons side "no duration" shouldn't happen; and if your version is better the -flac codec in ffmpeg should somehow get it right directly without additional "extract .flac from .oga and pack it again in .oga" steps. Be..anyone (talk) 21:51, 25 January 2014 (UTC)

Not sure if ffmpeg is broken or commons but flac forced into ogg is disgusting anyway. --McZusatz (talk) 22:42, 25 January 2014 (UTC)

Yeah, pointless without video or anything else Ogg might offer, but I didn't know that .flac needs no container. Oddly the folks whining about FLAC on Apple-devices don't push for ALAC. Be..anyone (talk) 12:50, 26 January 2014 (UTC)

Tracked in Phabricator
Task T62554

Its a bug on commons I think (The file is missing an "optional" field specifying its length). See bugzilla:60554. To be technical about it, .flac is also in a container format (Often called the "native flac container"), where Ogg is a container that goes around that container, and has more features. Bawolff (talk) 01:30, 29 January 2014 (UTC)