[gstreamer-bugs] [Bug 534570] New: Gstreamer plays flac files with the wrong channel mapping

[GStreamer (bugzilla.gnome.org)]

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  GStreamer | don't know | Ver: 0.10.7
           Summary: Gstreamer plays flac files with the wrong channel
                    mapping
           Product: GStreamer
           Version: 0.10.7
          Platform: Other
        OS/Version: All
            Status: UNCONFIRMED
          Severity: normal
          Priority: Normal
         Component: don't know
        AssignedTo: gstreamer-bugs at lists.sourceforge.net
        ReportedBy: seivadmas at gmail.com
         QAContact: gstreamer-bugs at lists.sourceforge.net
     GNOME version: 2.21/2.22
   GNOME milestone: Unspecified


Please describe the problem:
Title says it all really. The flac spec defines what the channel order should
be for various assorted channel configurations, it is available here:
http://flac.sourceforge.net/format.html#frame_header.

This is how flac defines channels:

    *  1 channel: mono
    * 2 channels: left, right
    * 3 channels: left, right, center
    * 4 channels: left, right, back left, back right
    * 5 channels: left, right, center, back/surround left, back/surround right
    * 6 channels: left, right, center, LFE, back/surround left, back/surround
right
    * 7 channels: not defined
    * 8 channels: not defined


Gstreamer seems to get this wrong, notably for 5.1 audio. Where it should be
reading the channels as FL,FR,CEN,LFE,RL,RR it actually reads the channels as
FL,FR,RL,RR,CEN,LFE which of course is the wrong way round. 

Steps to reproduce:
1. Play multichannel flac encoded according to actual flac standards
2. Hear sound come out of the wrong speakers


Actual results:
It depends on the number of channels I suppose it just results in sound coming
out of all the wrong channels.

Expected results:
It should come out of the correct channels!

Does this happen every time?
Yup!

Other information:
A test flac file made with audacity and alsa sample sounds is available here:

http://137.222.225.69:8008/Multichannel_test_flac_standard_6.flac

This has the channel ordering FL,FR,CEN,LFE,RL,RR which is the standard. Each
speaker should say in order which channel it is coming out of, except the lfe
channel, which plays a 60 hz tone for two seconds. Here is an 8 channel flac
made in a similar way except that the channels were jigged around to workaround
the bad channel mapping get it to play properly:

http://137.222.225.69:8008/Multichannel_test_flac_nonstandard_8.flac


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