Looking for a eac3 7.1 encoder

[j7n]

Is there a way of "labelling" (assigning) channels within Adobe Audition? From some formats it reads the positions (L, R, C, ...) and from others it does not (1, 2, 3, ...). This program is a weird marriage of ancient and modern GUI. Everything is invoked from a single nested Effects menu, and there is no toolbar for basic operations like Fade Out, because toolbars are apparently out of fashion now.

[BuccoBruce]

Is there a way of "labelling" (assigning) channels within Adobe Audition? From some formats it reads the positions (L, R, C, ...) and from others it does not (1, 2, 3, ...). This program is a weird marriage of ancient and modern GUI. Everything is invoked from a single nested Effects menu, and there is no toolbar for basic operations like Fade Out, because toolbars are apparently out of fashion now.

Short answer: not in a way that would help you when it comes to exporting 7.1 E-AC-3

Long answer: I have noticed that when I import WavPack files (because libsndfile will randomly fail to import specific FLAC files) with the proper channel mask set in the headers, the channels are labeled properly in the UI instead of being "1, 2, 3..." - probably has something to do with the WavPack plugin. However, it (the part of Audition that exports to DDP) still ignores those channel labels and maps the channels incorrectly, reading your channels only in the order it displays in the export menu, whether they're labeled "1, 2, 3..." or "L, R, C..." in Audition's UI.

This idiosyncrasy even extends to their own official DEE/DME - deew handles that for 7.1 by remapping your side/rear channels automatically.

[Balling]

It is not that simple, dolby media encoder assumes that you use SMPTE style of adm/wav64/wav. It's always backs before sides for Microsoft WAV. For SMPTE wav it is sides before backs.

But I did report it to Adobe, https://community.adobe.com/t5/audition-discussions/7-1-4-wav-is-not-reordered-and-horrible-bug-is-present-why-not-show-backs-before-sides/m-p/13476334

[writemaster]

I make a test also with TotalCode Studio.

We can configure it like with Audition with some differences:

1) For big files like movie tracks we need rf64 input files (without support for .w64).
And need remap or use the internal remap showed in the image. We can use eac3to:

eac3to 8v341.dtshd 8v341_R.rf64 -0,1,2,3,6,7,4,5

2) The max bitrate is also 1024 Kb/s but there are different channel layouts (see the images).
Without the (L R C LFE Ls Rs Vhl Vhr) than work fine with my audio system 3D 5.2.1.

3) Is fast than Audition.
In my previous old PC (Intel i5-3550 3.30GHz, DDR3 2+2 GB PC3-10700 (667 MHz), SATA ST2000DL003-9VT166 2TB) a source file (Jurasic Park 2h 6m 37s) converted previously to rf64 take 10m 36s to be converted to .ec3.
Audition take 4m to load the .w64 and after 14m to convert it to ec3.


With TotalCode Studio you can make Dolby Digital Plus 7.1 - 1536 bitrate sounds.

[tebasuna51]

With TotalCode Studio you can make Dolby Digital Plus 7.1 - 1536 bitrate sounds.

I test v5.3.0 and show until 1024, maybe you have other version?

[j7n]

You can in blu-ray mode with an AC-3 core (starting with a Blu-Ray preset). But it is not a good idea. 5 main channels = 640 kbit/s. 4 rear channels = 896 kbit/s.

[writemaster]

I test v5.3.0 and show until 1024, maybe you have other version?


I have same version.

https://images2.imgbox.com/f4/17/IWtZyxUA_o.png (https://imgbox.com/IWtZyxUA)

[DJ Bobo]

I test v5.3.0 and show until 1024, maybe you have other version?
You need to select a Blu-Ray preset under Output in order to show the higher bitrates

[tebasuna51]

Blu-ray mode (AC3 core) without sense, like j7n say:

You can in blu-ray mode with an AC-3 core (starting with a Blu-Ray preset). But it is not a good idea. 5 main channels = 640 kbit/s. 4 rear channels = 896 kbit/s.

[szabi]

Hi

Since my previous ask now I am in the situation I would like to do it again.
Are there any move forward regarding 7.1ch DD+ encoding?

Regards
szabi

Hi

Two years passed since quoted post and 10 years since the original asking (https://forum.doom9.org/showpost.php?p=1754063&postcount=170).
Any development?

Regards
szabi

[hellgauss]

I have written one open source, although it is experimental (and will remain experimental)
https://github.com/HG3112/md71

Nothing so difficult, just 10-20 lines of ffmpeg modification and a simple muxer. I do not know why it is not officially implemented in ffmpeg.

It has two .bat presets in which you can drop your 7.1 audio. Best way to change bitrate is to modify the first lines of .bat.

Doom9 thread: https://forum.doom9.org/showthread.php?t=186249
(the discussion on the tool starts on the second page, in the first one I was trying to modify plex encoder output)

[tebasuna51]

The hellgauss method work fine to make 7.1 eac3, but maybe you can read my post about Surround 3D (https://forum.doom9.org/showthread.php?p=2017558#post2017558) with my opinion about:

- The 7.1 layout (L R C LFE Ls Rs Lrs Rrs) 2D is only a way to waste money and bitrate because the same Surround 2D can be obtained with the 5.1 Layout (L R C LFE Ls Rs).
- Maybe you want Surround 3D with the layout 5.1.2 (L R C LFE Ls Rs Vhl Vhr), it can be obtained with Audition 2017 but also with a modified hellgauss method (also to AAC 5.1.2 with ffmpeg fdkaac).
- You can convert your 7.1 audio system in a 5.1.2

[szabi]

I missed that topic.
That is a good news.
Thanks.

[Balling]

There is now support in this upcoming patch https://code.ffmpeg.org/FFmpeg/FFmpeg/pulls/21668

[hellgauss]

Looks great! :thanks:

However I think there is a little imprecision in the code. I have zero experience in collaborating in software development, so I do not know how to post there.

The 1bit compre field in line 218 of eac3enc.c is always set to 0 for a dependent stream (no compression gain)

But in the A/52:2018 (https://www.atsc.org/atsc-documents/a522012-digital-audio-compression-ac-3-e-ac-3-standard-12172012/) in Annex E.3.8.5 :

"If multiple associated dependent substreams are present, only the last dependent substream may carry compr and dynrng"

and, most importantly, in the next paragraph

"Therefore, the compre bit in the last dependent substream of a program must be set to 1"

7.1 has only one dependent stream, which is the last. Perhaps is a little ambiguous, but I understood that compr-exists bit should be set to 1 and eventually set to zero compr (8bit). dynrng can be instead completely ignored.

There is also some bit counting to adjust in dep_compute_bit_allocation function (line 2237).