[FFmpeg-devel] PATCH: 5.1 AAC SMPTE channel order with libfaad

Jean-Yves Avenard jyavenard
Mon Apr 5 13:35:23 CEST 2010


Hi

On 5 April 2010 19:51, Benjamin Larsson <banan at ludd.ltu.se> wrote:
> That is the unneded hunk. Does the channel output configuration match
> the native decoder after your patch ?

yes it does.. It makes 5.1 decoded audio plays just fine in MythTV or
mplayer; just like when using ffmpeg internal decoder.

 [ Front Left ] [ Front Right ] [ Center ] [ LFE ] [ Surround Left ] [
Surround Right ]

It takes whatever libfaad output and put it back in that order (from
what I've seen, libfaad always output C L R SL SR LFE
There's a few more features than parametric stereo that makes libfaad
a requirement (I'm talking from a mythtv perspective here). First the
LATM/AAC patch available for libfaad (but my understanding is the
author is working to get something working with the native ffmpeg AAC
decoder)
and H264 HE-AAC used by few european countries for broadcast, and
likely going to be more and more used as countries are moving to the
new MPEG-4 AVC standard


I saw that extra line after I had posted the patch ; there's also a
mistake in a channel map array (-5 vs 5). I've attached an updated
copy. Sorry for that


I am very puzzled by M?ns Rullg?rd message. I don't see where else
channel re-ordering could be done than within the codec , it's how all
other codecs do it.

Thanks for looking into it
Jean-Yves
-------------- next part --------------
A non-text attachment was scrubbed...
Name: libfaad-smpte.patch
Type: application/octet-stream
Size: 3531 bytes
Desc: not available
URL: <http://lists.mplayerhq.hu/pipermail/ffmpeg-devel/attachments/20100405/06d94072/attachment.obj>



More information about the ffmpeg-devel mailing list