Wrong Channel mapping with 5.1 Ogg transcode with megui

[Bluedan]

Via update option the program (megui) and its components were up-to-date (as date of writing this): which means: v2.87 of oggenc was used.
The encode went fine, but obviously some central parts (narrators voice) moved to the right front - as far as my ears can tell me on 2.0 headphones - 5.1 Amp is planned for the future...
The voice is clearly centered in the source.

As stated here (http://www.rarewares.org/ogg-oggenc.php) the channelmapping bug, which kept me from using 5.1 conversions in the past, should have been fixed.

At last real multichannel ogg vorbis files should be possible by now!

The automatic avisynth script within megui contained this line:

[NoImage] 6==Audiochannels(last)?GetChannel(last,1,3,2,5,6,4):last


Is this line still valid? Should the channel order be changed (back/again)?
The source file ist ac3, decoded through NicAudio.
I don't find any info on the channel mapping of ogg compared to ac3. At least I know, that each multichannel capable format has a different channel number order.

Ogg vorbis is still my favorite from those days on, when HD space was very precious and 700MB (CD!) really ment the maximum size for transcodes.
I do not depend on stand-alone-players so I don't care for compatibility with other units.
I'd love to see ogg standing in the line with other multichannel audio formats....

BTW: Is surround channel coupling implemented now in ogg audio?

[tebasuna51]

6==Audiochannels(last)?GetChannel(last,1,3,2,5,6,4):last

Is this line still valid?

Of course not.
Now oggenc2.exe v2.87 don't need the remap.

[Bluedan]

OK. I assume you will be committing changes to the megui code then ?!

How do I circumvent this issue in the meantime?

If anyone else wonders: The other question about correct channel coupling with multichannel encodes is answered as well: it's implemented.

Hey-ho!

BTW: Is there a big difference between nicaudio and ffaudio decoding ac3 in this task?

[tebasuna51]

I'm not a MeGUI developer.
The bug is reported to Zathor: http://forum.doom9.org/showthread.php?p=1497670#post1497670

You can use BeHappy or Foobar2000 to recode ac3 -> ogg

I don't expect big differences between nicaudio and ffaudio decoding ac3, but I don't make ffaudio test.

[Bluedan]

Thank you.

Unfortunately the same line appears in Behappy again.
As long as the encode format is set to ogg, the above line appears as well in the avisynth script. Even when the ac3 source isn't multichannel at all.

So I managed it by editing the avs and feeding it via avisynth input to Behappy - encode went fine with correct channel order as far I can judge with my headphone experience. :)

Also, there seems to be no difference when ticking the omit encoder script box. I'm not sure if this option does what I take it for... I guessed it refers to those special encoder specific avs tweaks.
I googled around but found no explanation.

I didn't post this in the behappy thread because I'm not sure, if dimzon is still in charge with this programme!

[tebasuna51]

...
So I managed it by editing the avs and feeding it via avisynth input to Behappy - encode went fine with correct channel order
Yes, this work.

I didn't post this in the behappy thread because I'm not sure, if dimzon is still in charge with this programme!
Behappy is certified for encoder versions in readme.txt

If a encoder change the behaviour the GUI's must change also. I can make a new Behappy version to support oggenc2 v2.87, but I don't know when.

[Bluedan]

If a encoder change the behaviour the GUI's must change also. I can make a new Behappy version to support oggenc2 v2.87, but I don't know when.

:thanks: Would be very kind.

[Bluedan]

MeGui update:

From the changelog:
2014 [OggVorbis] removed channel remapping as it is not needed anymore

Yeah!