Project

General

Profile

Bug #4240

Sporadic DTS discontinuity errors in DVB-S ts recordings

Added by Oliver O over 7 years ago. Updated over 7 years ago.

Status:
New
Priority:
Normal
Assignee:
-
Category:
DVB
Target version:
-
Start date:
2017-02-17
Due date:
% Done:

0%

Estimated time:
Found in version:
4.1-2405~geb495a0~xenial
Affected Versions:

Description

Some DVB-S ts recordings (15 out of 56) contain DTS discontinuity errors, leading to playback problems (when skipping forward/backward). The beginning of one example is attached. In all but one case, the errors appear in recordings where EIT p/f was used.

Such ts recordings can be fixed with a post-processing script using a line like this:

ffmpeg -v fatal -probesize 500M -analyzeduration 1000M -i "$input" -map 0 -vcodec copy -acodec copy -sn "$output"

It would be ideal if anything inside TVH could prevent this from happening in the first place.

History

#1

Updated by Oliver O over 7 years ago

(Upload of 200 MB failed with "Request Entity Too Large" though the hint next to the "Browse" button says "Maximum size: 488 MB".)

Providing the example here for a limited time: https://dl.dropboxusercontent.com/u/29731283/dts-discontinuity-example-1a.ts

#2

Updated by Jaroslav Kysela over 7 years ago

DTS/PTS is not altered by TVH when the recording is paused using the EITp/f running state detection. So yes, there may be gaps in DTS/PTS.

#3

Updated by Oliver O over 7 years ago

Thanks for the explanation.

Just to clarify the incidents I've experienced: Where EIT p/f was used, the program was never interrupted by commercial breaks. All recordings were scheduled with a Pre-recording padding of 5 minutes and a Post-recording padding of 15 minutes.

So it was basically the recording
  • starting 5 minutes before schedule, then
  • receiving the running_status of Running,
  • receiving the entire program without breaks, then
  • receiving the running_status of Completed.

I haven't yet looked at the details how TVH handles this, but I hope this clarification helps if at some point there is an interest to address the issue.

Also available in: Atom PDF