So, I was making sure that channel assignments and/or downmixing worked well, and tested eac3to on a bunch of channel checks I had available.
The FFmpeg TrueHD decoder was swapping the side and back surround channels. That was fixed recently:
http://git.videolan.org/?p=ffmpeg.gi...diff;h=6daf513
Given that eac3to 3.24 is much older than that fix, it should have been affected by the bug - but to my surprise, it wasn't.
I used a TrueHD 7.1 channel check available on demo-world.eu
I tested it this way:
Code:
eac3to.exe input.mkv 2: output.wavs
and all the channels seemed to be in the correct file, in particular:
output.SL.wav -> left side surround
output.SR.wav -> right side surround
output.BL.wav -> left back surround
output.BR.wav -> right back surround
So I tested it on a DTS-HD MA 7.1 channel check from the Disney World of Wonder Blu-ray, and got incorrect results:
output.SL.wav -> left
back surround
output.SR.wav -> right
back surround
output.BL.wav -> left
side surround
output.BR.wav -> right
side surround
Code:
eac3to.exe -test
eac3to (v3.24) is up to date
Nero Audio Decoder (Nero 6 or older) doesn't seem to be installed
http://www.nero.com/eng/store-blu-ray.html
CAUTION: You need Nero 7. Nero 8 won't work with eac3to.
ArcSoft DTS Decoder (1.1.0.0) works fine
Sonic Audio Decoder (3.24.0.0) doesn't seem to be installed
Haali Matroska Muxer (2011-03-03) is up to date
Nero AAC Encoder could not be located
http://www.nero.com/eng/nero-aac-codec.html
Copy NeroAacEnc.exe to the eac3to or to the Windows folder.
Surcode DTS Encoder doesn't seem to be installed
http://www.surcode.com
MkvToolnix (5.0.0.0, release version) is up to date
There are a couple possibilities:
1)
- the FFmpeg TrueHD decoder is patched in eac3to to fix the channel swap bug, and either:
- - a. the Arcsoft DTS decoder is swapping channels
- - b. eac3to is remapping channels incorrectly from DTS-HD MA 7.1 sources
2)
- the side and back surround channels are swapped internally in eac3to, affecting all 7.1 sources
- the FFmpeg and eac3to bugs cancel each other out
In the latter case, remapping should always be used when dealing with 7.1 sources, whether downmixing or not:
…except when using the FFmpeg decoder and the source is TrueHD 7.1.
Here are the WAV files output by eac3to:
no remapping:
http://www.mediafire.com/?3r35vr7gpg3v008
-0,1,2,3,6,7,4,5:
http://www.mediafire.com/?68q021d69doy8va