[mythtv-users] Timing issue

[Tom Hughes]

In message <5614711e4d.tom at loxley.compton.nu>
          Tom Hughes <tom at compton.nu> wrote:

> In fact tonight I was watching something while it was still recording
> and to start with both the current position and the duration were
> incrementing and the duration got to about 1h5m and was still going
> up. Later on I looked and the position was still incrementing but the
> duration had dropped back to about 59m and frozen. The video played
> on past that point and when I then started the program again after it
> had finished the duration was back to where it should be at 1h10m or so.

I've been investigating this some and it appears to be consistent in
that it always happens if I'm watching a program while it is still
recording that when the recording finishes the end time jumps back.

Last night I had a dig in the source and traced some of what was
going on and it looks like the problem is the DONE_RECORDING message
that the backend sends - it has the wrong length in it. That length
is used to update the length used for the on screen display.

The recording I traced was 62 minutes long (a one hour program with
a two minute global pre-roll) and the recording was a DVB-T stream
with 25 frames/sec. The message sent by the backend when the recording
finished was:

  BACKEND_MESSAGE[]:[]DONE_RECORDING 2 3159[]:[]empty

The value 3159 is the final length of the recording, and corresponds
to 52 minutes and 39 seconds, which is some 10 minutes short.

Querying the recordedmarkup table for that program appears to give
the correct answer - the maximum frame number is 94687 which corresponds
to 63 minutes 3.12 seconds at 25 frames/sec.

So the question is, why is the backend reporting the wrong length
when the recording finishes? Is anybody else seeing this?

Tom

-- 
Tom Hughes (tom at compton.nu)
http://www.compton.nu/