[mythtv] Empty PAT Un-Recordable?

[Janne Grunau]

On Sunday 12 August 2007 15:05:08 Dave Allen Barker Jr wrote:
> I've had a working installation for some years. Last week, a single
> ATSC channel (WPBA <http://en.wikipedia.org/wiki/WPBA>) generated
> scheduled recording files of zero size, and failed to play live
> (stalling at "La___"). "mplayer" though is able to play this trouble
> channel successfully.

The backend doesn't see the serviceid (program number) in the PAT. Try 
rescanning the transport.

> Investigating into realms I know little of lead me to the idea that
> the station has stopped transmitting the PIDs in the PAT (again, I'm
> not familiar with such things—hopefully you can make some sense).
> Some folks on #mythtv-users suggested I mention here what I've found.

It might transmit the channel under a different program number or on a 
different channel.

> I can provide backend logs if you'd like.  Here's what "dvbsnoop -s
> pidscan" had to say.
>
>     $ dvbsnoop -s pidscan
>     dvbsnoop V1.4.00 -- http://dvbsnoop.sourceforge.net/
>
>     ---------------------------------------------------------
>     Transponder PID-Scan...
>     ---------------------------------------------------------
>     PID found:    0 (0x0000)  [SECTION: Program Association Table
> (PAT)] PID found:   48 (0x0030)  [SECTION: Program Map Table (PMT)]
> PID found:   49 (0x0031)  [PES: ITU-T Rec. H.262 | ISO/IEC 13818-2 or
> ISO/IEC 11172-2 video stream]
>     PID found:   52 (0x0034)  [PES: private_stream_1]
>     PID found: 4433 (0x1151)
>     PID found: 8191 (0x1fff)
>     $
>
> Could it be that the station is actually broadcasting a broken
> stream?  Why should mplayer work and mythtv not?  Is there anything I
> can do to help fix it (mythtv or the channel)?

It finds a PAT and a PMT. I would need the decoded PAT and PMT and the 
relevant entries of the channel and dvb_multiplex tables to tell what's 
wrong. But rescanning that transport should fix it.

Janne