Pelvis Popcan
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I ripped a Blu-Ray using AnyDVD + CloneBD, and I need to extract the Dolby TrueHD Atmos 7.1 audio to a 32 bit float .wav file for some special manipulations I'm doing.
I used CloneBD to rip to .mkv, then extracted the Dolby 7.1 audio track (with no re-encoding, if that's not obvious). In both the .mkv file and the extracted .mlp audio file, the channel mapping as viewed by MediaInfo is:
So, according to the above, channels 1 and 2 are front left and front right, channel 3 is center, and channel 4 is LFE. That's all fine, no confusion.
For Dolby 5.1, it's also easy to understand that channels 5 and 6 are side surround left and side surround right.
So, in 7.1, according to CloneBD's output, channels 5 and 6 are side surround left and side surround right, and channels 7 and 8 are back surround left and back surround right.
To convert to RIFF64 8 channel .wav (since it will be over 4 GB), I'm using the following command:
This works and I get an 8 channel 32 bit float .wav file, but in looking at output.wav in MediaInfo, it shows a different channel mapping:
So now I have a dillema! There's apparently two standards... one where channels 5 and 6 are side surround left and side surround right (CloneBD rip), and one where channels 5 and 6 are back surround left and back surround right (conversion to .wav file).
So I need to know which is correct.
I'm also even further confused because I'm not sure that when I run the above FFmpeg command that it isn't actually changing the channel positions, or if the change in channel mapping that I'm seeing in MediaInfo is just something like a tag or label. In any case, I still need to know what is correct, so as I'm working with this I don't end up with the side surround channels coming out of the back surround speakers and vice versa.
I used CloneBD to rip to .mkv, then extracted the Dolby 7.1 audio track (with no re-encoding, if that's not obvious). In both the .mkv file and the extracted .mlp audio file, the channel mapping as viewed by MediaInfo is:
L R C LFE Ls Rs Lb RbSo, according to the above, channels 1 and 2 are front left and front right, channel 3 is center, and channel 4 is LFE. That's all fine, no confusion.
For Dolby 5.1, it's also easy to understand that channels 5 and 6 are side surround left and side surround right.
So, in 7.1, according to CloneBD's output, channels 5 and 6 are side surround left and side surround right, and channels 7 and 8 are back surround left and back surround right.
To convert to RIFF64 8 channel .wav (since it will be over 4 GB), I'm using the following command:
ffmpeg.exe -i "input.mlp" -rf64 auto -c:a pcm_f32le "output.wav"This works and I get an 8 channel 32 bit float .wav file, but in looking at output.wav in MediaInfo, it shows a different channel mapping:
L R C LFE Lb Rb Ls RsSo now I have a dillema! There's apparently two standards... one where channels 5 and 6 are side surround left and side surround right (CloneBD rip), and one where channels 5 and 6 are back surround left and back surround right (conversion to .wav file).
So I need to know which is correct.
I'm also even further confused because I'm not sure that when I run the above FFmpeg command that it isn't actually changing the channel positions, or if the change in channel mapping that I'm seeing in MediaInfo is just something like a tag or label. In any case, I still need to know what is correct, so as I'm working with this I don't end up with the side surround channels coming out of the back surround speakers and vice versa.