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#328 wrong channel mapping for 7.1 AAC streams

open
nobody
None
5
2012-12-18
2012-12-18
Anonymous
No

Looking at the specification from
http://developer.apple.com/library/mac/#documentation/MusicAudio/Reference/CoreAudioDataTypesRef/Reference/reference.html#//apple_ref/doc/c_ref/kAudioChannelLayoutTag_AAC_7_1
the channels are decoded correctly for 7.1 aac files but it looks like they're mapped/mixed in the wrong way resulting in the following output behaviour:
left -> left + center
center -> center
right -> right + center
right surround -> right
left surround -> left
right rear surround -> right rear surround
left rear surround -> left rear surround
lfe -> lfe

As a side note VLC seems to map these channels correctly but that's the only decoder / player which was able to play 7.1 aac files correctly so far. The issue itself probably lies within the audio systems (drivers) not being able to handle recognize/handle left center and right center channels correctly. I'd say I could ignore the issue if it was fixable with a custom matrix but since even the matrix mixer does not support / handle this setup correctly this is no possible.

If you need a test sample refer to the dropbox link here:
http://forum.xbmc.org/showthread.php?tid=147170&pid=1259665#pid1259665

If you need anything I'll be willing to help as far as I can.

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