GNOME Bugzilla – Bug 140141
[qtdemux] cannot playback gsm audio
Last modified: 2005-01-28 10:36:12 UTC
I can't play the following file with gstreamer: ftp://ftp.mplayerhq.hu/MPlayer/samples/A-codecs/GSM/sample-gsm-8000.mov It shows the following error message on the console: ** (totem:22758): CRITICAL **: Don't know how to convert fourcc 'agsm' to caps So, I guess someone needs to write a gsm decoder. Plays fine in MPlayer.
We do, gsmdec. I guess the fourcc isn't handled in qtdemux.
We do now, and gsmdec is fixed as well... It doesn't play back yet, it appears to have alignment issues. I need help from someone familiar with GSM in Quicktime here. Gsmdec handles MS GSM 10:6, and Quicktime contains Apple GSM 10:1. It's apparently different. If I handle each buffer from the start (and thus remove the storage) from gsmdec, parts work, but others don't, which is why I think there's alignment issues. Anyway, I don't know how to fix this right now... I guess MS GSM 10:6 has different block alignments (33 bytes for MS GSM 10:6) than Quicktime GSM 10:1, but there's no docs on this, so...
Created attachment 36620 [details] [review] testcase for ffmpeg With the attached patch (see also #14555/#155163), we can play this file fine, so apparently, see the other two bugs, this is a qtdemux bug.
Given the above bugs, I checked samplesize, and they're exactly 1/0.103125 (320/33) too large. Adding that as compression/BPF factor in qtdemux.c fixes this file.
Fixed.