Welcome to Doom9's Forum, THE in-place to be for everyone interested in DVD conversion. Before you start posting please read the forum rules. By posting to this forum you agree to abide by the rules. |
20th September 2014, 17:07 | #12802 | Link |
Registered User
Join Date: May 2005
Posts: 1,462
|
Not sure it qualifies as a bug per se. Since the Atmos TrueHD stream is said to be fully backwards compatible (= can be played on regular players), I can only draw the conclusion, that they put the Atmos 'ceiling' channels into the metadata (which receivers are supposed to ignore; which is why this works, I presume).
So, all we really need is a knowledgeable coder (you?!) who will strip off the metadata, so we have a regular TrueHD stream again, right?
__________________
Gorgeous, delicious, deculture! |
20th September 2014, 17:37 | #12803 | Link |
Registered User
Join Date: Sep 2006
Posts: 2,197
|
imho it would be preferable being able to decode the entire stream completely.
__________________
Laptop Lenovo Legion 5 17IMH05: i5-10300H, 16 GB Ram, NVIDIA GTX 1650 Ti (+ Intel UHD 630), Windows 10 x64, madVR (x64), MPC-HC (x64), LAV Filter (x64), XySubfilter (x64) (K-lite codec pack) |
20th September 2014, 17:50 | #12804 | Link |
Registered User
Join Date: Sep 2012
Posts: 110
|
When I use the command to extract the Dolby Atmos to mono wavs. I get this error:
Code:
eac3to v3.24 command line: eac3to.exe "trans.4.thd+ac3" Vie.wavs ------------------------------------------------------------------------------ The format of the source file could not be detected. <ERROR> |
20th September 2014, 17:51 | #12805 | Link | |
Registered Developer
Join Date: Mar 2010
Location: Hamburg/Germany
Posts: 10,348
|
Quote:
Regarding getting the original TrueHD stream out, its not that easy, its not just metadata you have to ignore, its properly integrated into the TrueHD codec itself, and will need proper fixing of the decoder. Its possible that it would work if we had an "official" TrueHD decoder or a specification, but since the ffmpeg/libav TrueHD decoder is practically reverse engineered, it lacks the ability to deal with those streams, for now.
__________________
LAV Filters - open source ffmpeg based media splitter and decoders Last edited by nevcairiel; 20th September 2014 at 17:56. |
|
20th September 2014, 17:59 | #12806 | Link |
Registered User
Join Date: May 2005
Posts: 1,462
|
Then I wonder how current receivers are able to play the Atmos-enhanced TrueHD stream just fine, if the Atmos data were really a part of the main TrueHD stream. There's obviously some 'easily' discardable info, or current receivers would not be able to pull it off cleanly.
__________________
Gorgeous, delicious, deculture! |
20th September 2014, 18:44 | #12807 | Link |
Registered Developer
Join Date: Mar 2010
Location: Hamburg/Germany
Posts: 10,348
|
Like I said, if we had the specification of TrueHD, it could tell us what is wrong, but since Dolby is not giving that out, its not that easy.
__________________
LAV Filters - open source ffmpeg based media splitter and decoders |
20th September 2014, 21:10 | #12808 | Link | |
Registered User
Join Date: Sep 2006
Posts: 2,197
|
Quote:
maybe the guy knows who told madshi how to deal with the TrueHD track headers back then when there were those THD delay problems because madshi accidentally stripped too much from these tracks.
__________________
Laptop Lenovo Legion 5 17IMH05: i5-10300H, 16 GB Ram, NVIDIA GTX 1650 Ti (+ Intel UHD 630), Windows 10 x64, madVR (x64), MPC-HC (x64), LAV Filter (x64), XySubfilter (x64) (K-lite codec pack) |
|
21st September 2014, 02:29 | #12809 | Link | |
Angel of Night
Join Date: Nov 2004
Location: Tangled in the silks
Posts: 9,559
|
Quote:
|
|
21st September 2014, 03:36 | #12812 | Link | |
Registered User
Join Date: May 2005
Posts: 1,462
|
Quote:
And, even though I understand it's just temporary, I would *still* like ffmpeg/eac3to to retain the option to merely extract the TrueHD core (akin to extracting an AC3 core from the TrueHD stream), so as to have something playable/usable on my system. P.S. Thanks for the speedy patch!
__________________
Gorgeous, delicious, deculture! |
|
21st September 2014, 04:36 | #12815 | Link |
Registered User
Join Date: May 2005
Posts: 1,462
|
Yeah, someone please tell us where this alleged patch resides: the 'posted' patch is just a mailing list post.
I tried the latest binary, and it says: Code:
c:\eac3to\ffmpeg -i "test.m2ts" -vn -ac 8 -acodec pcm_s24le -f wav c:\video\temp.wav [truehd @ 02bb57e0] major sync info header checksum error Last message repeated 42 times [NULL @ 02bb57e0] start time for stream 1 is not set in estimate_timings_from_pts [mpegts @ 02bb9080] Could not find codec parameters for stream 1 (Audio: truehd (AC-3 / 0x332D4341), 0 channels): unspecified sample format Code:
Mixing surround channels... Writing WAV... Creating file "c:\video\finak.wav"... Original audio track, L+R+C+LFE+SL+SR: constant bit depth of 24 bits Original audio track, BL+BR: no audio data. The processed audio track has a constant bit depth of 24 bits.
__________________
Gorgeous, delicious, deculture! |
25th September 2014, 11:06 | #12819 | Link | |
Registered User
Join Date: May 2005
Posts: 1,462
|
Quote:
http://ffmpeg.zeranoe.com/builds/
__________________
Gorgeous, delicious, deculture! |
|
28th September 2014, 15:02 | #12820 | Link | |
the Interrogator
Join Date: Oct 2001
Location: DownUnder
Posts: 664
|
Quote:
TIA Last edited by JimmyBarnes; 28th September 2014 at 15:19. |
|
Tags |
eac3to |
|
|