+- Kodi Community Forum (https://forum.kodi.tv)
+-- Forum: Support (https://forum.kodi.tv/forumdisplay.php?fid=33)
+--- Forum: General Support (https://forum.kodi.tv/forumdisplay.php?fid=111)
+---- Forum: OS independent / Other (https://forum.kodi.tv/forumdisplay.php?fid=228)
+---- Thread: Bug 6.1 Opus Audio Channel Mapping? (/showthread.php?tid=377130)
6.1 Opus Audio Channel Mapping? - Grim Reefer - 2024-04-16
I have a movie with a 6.1 opus audio track. During playback it sounds like the channel mapping is incorrect (dialog is in rear right channel, etc)
When I press o to get the "Player Process Information OSD" it says the channel maps are:
Audio stream: FL, FR, FC, LFE, BC, SL, SR, ff-opus 32 bits, 48,000 Hz
But when I check the opus spec, its says the channelmap should be:
7 channels: 6.1 surround (front left, front center, front right, side left, side right, rear center, LFE).
https://datatracker.ietf.org/doc/html/rfc7845.html#section-5.1.1.2
When I play a 6.1 dtsma audio track the channels sound correct, and the reported channel mapping is the same order.
Is kodi using the correct channel mapping for 6.1 opus audio?
I am using version 20.2.0 on linux.
61
RE: 6.1 Opus Audio Channel Mapping? - Grim Reefer - 2024-04-16
Found the problem. It is with ffmpeg's opus encoder, not kodi's playback.
Evidently ffmpeg has a bug that gets the channel map wrong for 6.1. But there is a work around, add "-mapping_family 1" like so:
-c:a:0 libopus -b:a:0 700k -mapping_family 1
Reportedly that causes ffmpeg to use a newer api to talk to the libopus library. It sounds like it is safe to add that regardless of the number of channels too.