[mythtv-users] Mythtranscode: Deadlock detected.

[James Linder]

> On 9 Jan 2023, at 7:13 pm, Paul Harrison <mythtv at mythqml.net> wrote:
> 
> On 09/01/2023 03:20, James Linder wrote:
> 
>> 
>>> On 9 Jan 2023, at 10:24 am, A. F. Cano <afc54 at comcast.net> wrote:
>>> 
>>> On Wed, Dec 21, 2022 at 06:59:36AM +0800, James wrote:
>>>> ...
>>>>   I've got an h264cut.sh that I use almost daily on Australian commercial
>>>>   and ABC channels that anyone may ask for.
>>> I wouldn't mind giving it a try…
>> http://tigger.ws/downloads/h264cut.sh
>> 
>>>>   A while back someone used the script and it did not work for them!
>>>>   It uses mythffmpeg to do lossless cuts and mythffmpeg to paste the
>>>>   segments together again
>>> Does it use the cutpoints created with the front-end, and thus the
>>> mythtv db?
>> Yup
>> 
>>> I have managed to do the extraction of the one chunk I needed with
>>> kdenlive, which seems to be a powerful video editor, from a copy of
>>> the file, but I only use the one feature: import a clip (whtch is
>>> the whole show), find the spot for the first cut point, select that
>>> with the -| button, which deletes (or marks for deletion) from
>>> beginning to there, find the other cut point, use the |- button to
>>> delete from there to the end and export the remaining chunk to a file.
>> I use ffmpeg. I want it automated and quick
>> 
>> /store			# where my recordingd are
>> /store/Movies/Myth[A-Z] # where the videos go
>> /store/TScut_work	# working dir
>> 
>> change to suit yourself
>> 
>> Example (looking at FE)
>> 
>> h264cut.sh
>> 0108
>> choose /store/10020_20230108110000.ts
>> The Unwashed
>> u		# cause I want it stored in Myth_U not Myth_T
>> 
>> It would be trivial to do, but I’ve not done it: If you run 2x without removing the target ffmpeg baulks at ‘overwrite'
>> 
>> James
> 
> 
> How well does it manage to keep the audio in sync?
> 
> 
> Having worked on MythArchive for many years one of the big problems was always cutting the commercials and keeping the audio in sync. The problem is the length in time of the video frames and audio frames are not always the same so the more cuts you have the bigger the problem becomes. If you just top and tail then it will probably be OK since there is really only the first cut affecting the sync. If you have maybe a 2 hour movie with 8 or more adverts to cut out then the sync can be way off at the end. In MythArchive we did things like insert blank audio packets to try to keep the audio in sync which worked well most of the time but was not 100% and depended a lot on where the source came from.
> 
> 
> It's a long time since I played with this stuff so maybe the source video and/or the tools available have improved since then? I'm curious to know.

Paul I can honestly proclaim:
I have cut commercials from all the Australian commercial channels and pruned head and tail from ABC which is commercial free (sic)* and for over 1000 recordings I have no sync issues.
I’ve never investigated but ffmpeg is used in copy mode so no transcoding takes place so sync is not an issue.

* “On Sunday we explore … and  lots of preamble drivel”
James