Opened 7 years ago
Last modified 2 months ago
#3595 open enhancement
Support >6 channels in E-AC-3 audio encoder
Reported by: | 11rcombs | Owned by: | |
---|---|---|---|
Priority: | wish | Component: | avcodec |
Version: | git-master | Keywords: | eac3 |
Cc: | LigH, rodger.combs@gmail.com, j.kis@me.com, hoffbrinkle@hotmail.com, Nomis101@web.de, ohneherren@gmail.com | Blocked By: | |
Blocking: | Reproduced by developer: | yes | |
Analyzed by developer: | no |
Description
E-AC-3 supports up to 15 full-bandwidth channels, but libavcodec's encoder currently doesn't support 6.1 and 7.1 channel layouts. Do these layouts just need to be added to ff_ac3_channel_layouts, or would this require additional work on the encoder?
Attachments (5)
Change History (31)
comment:1 Changed 7 years ago by cehoyos
- Priority changed from minor to wish
- Reproduced by developer set
- Status changed from new to open
- Summary changed from Support >5 channels in E-AC-3 audio to Support >6 channels in E-AC-3 audio
comment:2 follow-up: ↓ 7 Changed 4 years ago by LigH
Changed 4 years ago by LigH
7.1 channel Blu-ray E-AC-3 with 5.1 AC-3 core and 2 dependent substreams
comment:3 Changed 4 years ago by cehoyos
- Cc LigH added
Is this the one sample we know about (from a demo disk) or a new file?
comment:4 Changed 4 years ago by LigH
AFAIK it's a new file, extracted from a Blu-ray by a Gleitz forum member.
http://forum.gleitz.info/showthread.php?47670-e-ac3-richtig-convertieren
comment:5 Changed 4 years ago by cehoyos
Then please ask for a longer sample that provides actual audible sound (at least 2,5M) and ask which Bluray this is.
comment:6 Changed 4 years ago by cehoyos
Two minute eac3 7.1 sample (that does not come from the demo disk) uploaded to http://samples.ffmpeg.org/ffmpeg-bugs/trac/ticket3595/
comment:7 in reply to: ↑ 2 Changed 4 years ago by dcxero
Replying to LigH:
Possibly relevant: MediaInfo? does not recognize it correctly either (e.g. reports an obviously improbable bitrate of 500 bytes per second).
MediaInfo? only seems to have a bug reading 7.1 Dolby Digital Plus tracks authored using the Blu-ray Disc profile (which is what the other samples use). It can read 7.1 Dolby Digital Plus tracks authored using the standard profile (which is used more for software and file/streaming distribution)
Here is a Standard profile 7.1 sample: https://www.datafilehost.com/d/ae18d85c
comment:8 Changed 3 years ago by richardpl
- Summary changed from Support >6 channels in E-AC-3 audio to Support >6 channels in E-AC-3 audio encoder
comment:9 Changed 3 years ago by johnesz
- Cc j.kis@me.com added
comment:10 Changed 2 years ago by hoffer
- Cc hoffbrinkle@hotmail.com added
comment:11 Changed 12 months ago by ackbc
- Reproduced by developer unset
ffmpeg doesn't support encode 7.1 files into 7.1 EAC3
i've uploaded some samples for testing (three 7.1 files), i hope it could support 7.1 EAC3 encode, input output
the closed, dupe ticket https://trac.ffmpeg.org/ticket/8519
update: samples uploaded here.
Changed 12 months ago by ackbc
Changed 12 months ago by ackbc
Changed 12 months ago by ackbc
Changed 12 months ago by ackbc
comment:12 Changed 12 months ago by cehoyos
- Reproduced by developer set
comment:13 Changed 10 months ago by Nomis101
- Cc Nomis101@web.de added
This is also an annoying issue for HandBrake?: https://github.com/HandBrake/HandBrake/issues/1085
What makes it so difficult to support >6 channels for E-AC3 encoding?
comment:14 follow-up: ↓ 15 Changed 10 months ago by richardpl
Missing actual sponsor.
comment:15 in reply to: ↑ 14 Changed 10 months ago by Nomis101
Replying to richardpl:
Missing actual sponsor.
Thats all? How to find a sponsor? Who can be a sponsor?
comment:16 Changed 10 months ago by richardpl
The one with lot of money.
comment:17 Changed 10 months ago by LigH
They possibly mean: someone willing to pay for access to confidential specifications, level "trade secret, and we have lawyers to protect it".
comment:18 follow-up: ↓ 19 Changed 10 months ago by richardpl
Nope, look what I said and please stop spreading false information.
comment:19 in reply to: ↑ 18 Changed 10 months ago by jdlh
Replying to richardpl:
Nope, look what I said and please stop spreading false information.
I'm new to the ticket. @richardpl, I'm afraid your comment:14 is a bit too cryptic for me to understand, especially given how in comment:18 you seem to say that the interpretation in comment:17 is "false information".
Could you please say clearly what you mean by "missing actual sponsor"? What does the sponsor do with their "lot of money"? Who do they give it to? How does it help?
It seems to me that part of what that money would do is pay for access to specifications. But you apparently don't mean that. Maybe it would pay a competent developer to write the necessary code? What do you mean, please?
comment:20 Changed 10 months ago by richardpl
It means to write code. Specification is already available.
comment:21 Changed 10 months ago by LigH
Regarding code, I would call that rather "contributor" than "sponsor". Hence the misunderstanding, maybe... contributing code is hopefully not bound to huge amounts of money. At least I wish.
comment:22 Changed 10 months ago by richardpl
If you want to contribute code and time without any compensation, be my guest.
comment:23 Changed 5 months ago by TwoLeaves
- Cc ohneherren@gmail.com added
This does not only belong to the E-AC-3 encoder, but also to the decoder or the format recognition in general. There is a report in the German doom9/Gleitz video forum that ffmpeg does not even recognize a 7.1 channel Blu-ray audio stream correctly, which consists of a 5.1 AC-3 core and additional E-AC-3 channels. It may have been related to a slightly older version; a rather current ffmpeg version (N-81308-g369ed11, 2016-08-09) prints a warning that it will handle only the 5.1 core:
Possibly relevant: MediaInfo? does not recognize it correctly either (e.g. reports an obviously improbable bitrate of 500 bytes per second).