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.


Go Back   Doom9's Forum > General > Audio encoding

Thread Tools Search this Thread Display Modes
Old 13th June 2019, 23:17   #14841  |  Link
Registered User
Join Date: Jul 2015
Posts: 109
I often use eac3to to demux BD streams. In the past I've noted a common delay of just above 21ms (there's a remaining delay of less than 1ms) when dealing with DTSHD track transcoding (eg. DTSHD > FLAC). At the time, I read up on this a fair bit and did some of my own testing, eventually concluding that a simple "-21ms" parameter would be ideal when dealing with DTSHD in this way.

There's plenty of discussion about this, but a lot of it seems related to specific issues and I can't find anything conclusive about whether or not this is the right way to approach this. I'm not sure if there is a "correct" way to do this (for instance a trim based on samples / frames to make it align perfectly or some internal function that does this), or if I should be touch this value at all. I believe it's an encoder delay (and not a decoder delay, but I could be wrong) and so it stands to reason that if this is true, perhaps some BDs have been authored with compensation for this delay in mind.

I was wondering if the way I'm handling it is the correct procedure, or is there a better way?
thecoreyburton is offline   Reply With Quote
Old 14th June 2019, 02:33   #14842  |  Link
tebasuna51's Avatar
Join Date: Feb 2005
Location: Spain
Posts: 5,530
It is know than encoders add initial silence samples to initialize some encoders buffers, for instance if you recode to AC3 you obtain a delay of 5 ms, until 38 ms with some AAC encoders.

But with some encoders that delay is stored in metadata and any decoder must restore the audio without delay. For instance AAC in mp4 container (.m4a) must play without delay.
I can't reproduce the problem recoding DTSHD to FLAC, for me the obtained .flac is decoded without delay.
BeHappy, AviSynth audio transcoder, in Doom9 forums. NicAudio, BassAudio, audio decoders.
tebasuna51 is offline   Reply With Quote
Old 5th July 2019, 15:47   #14843  |  Link
Registered User
Join Date: Mar 2007
Posts: 100
Are we going to see a new version that supports HEVC? Last version is almost a year old
zeropc is offline   Reply With Quote
Old 5th July 2019, 16:39   #14844  |  Link
Registered User
Join Date: Dec 2002
Posts: 5,388
eac3to v3.32 "added support for h265/HEVC bitstream parsing". So your feature request seems too unspecific. Either way eac3to development seems pretty much stalled. Not much you can do except make a proper feature request on madshi's tracker and keep fingers crossed he finds time/interest to work on it again ...
sneaker_ger is offline   Reply With Quote


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

All times are GMT +1. The time now is 19:02.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.