[mythtv] Fwd: Subtitles and Comcast x264
pgbennett at comcast.net
Wed Nov 9 18:43:39 UTC 2016
Oops - i meant this to go to developers not the users mailing list.
-------- Forwarded Message --------
Subject: Subtitles and Comcast x264
Date: Wed, 9 Nov 2016 13:41:32 -0500
From: Peter Bennett <pgbennett at comcast.net>
To: Discussion about MythTV <mythtv-users at mythtv.org>
Regarding the new Comcast 720p x264 broadcasts, which started recently
as they convert cable channels.
MythTV does not detect the subtitles. Also ffmpeg does not seem to find
them. Mediainfo reports the subtitles, and vlc finds then if I play the
ts file. HandBrake does not find them.
Do we just wait and hope that one day ffmpeg, vdpau, openmax, etc will
ccextractor (from sourceforge) finds the subtitles and creates a srt
file in a short time. Mythccextractor runs for a long time and does not
find the subtitles.
Recording playback is able to use a .srt file, but IIRC the file has to
be named in a non-standard way, as for example
3763_20161107030000.ts.srt instead of just 3763_20161107030000.srt. It
will only accept one file named this way, it will not accept .en.srt for
English subtitles or .de.srt for German, etc.
With the current above mentioned naming convention, when the video is
deleted the subtitle file is not deleted.
Other than waiting for ffmeg, vdpau, openmax, etc, developers to catch
up, perhaps we can incorporate ccextractor in some way. People can use
ccextractor in a custom job to extract subtitles, but this does not help
with Live TV or watching recordings in progress if the job only runs at
the end of the recording.
1. Fix the way MythTV looks for subtitle file names and making sure
those will be deleted when the recording is deleted.
2. Incorporate ccextractor into the backend or modify it so that it can
run while the recording is in progress to create a srt file or files
that can be used by Live TV.
3. Make sure Live TV can use correctly named subtitle files and that
they can be used during recording.
4. Ccextractor to make sure subtitle files are named according to a
standard. There may not be a language flag for multiple subtitles, so
maybe just call them .01.srt, .02.srt and so on.
4. Frontend able to present multiple subtitle files and allow the user
to select one. Currently it only allows one "external" subtitle.
I would need to decide how and when to activate this process. The
backend may not know if the subtitles are in a format the frontend will
not understand. Perhaps this should be a job that is run when a
recording starts. I am not sure how we trigger a job when a recording
starts. Also I don't know how we write a job that reads a recording file
while it is being written, and knows when the recording is complete so
that it can end (When is an end of file the end of a recording vs the
point up to which it has recorded so far?).
I think I had seen mentioned that you can transcode during recording. Is
this true and how does it get invoked? I can look at that code to see
how they do it.
Phase 1 could be fixing so that a user job can run after a recording to
create the subtitles, frontend to support correctly named subtitles and
those subtitles to get deleted when the video is deleted. This would
satisfy all except watching while recording and LiveTV.
Any comments/ suggestions on this? Is it a good idea?
-------------- next part --------------
An HTML attachment was scrubbed...
More information about the mythtv-dev