[mythtv-users] mythtv-setup DVB-T channel scanning problems (was: Re: should be local, but it can not be found)

Brent Bolin brent.bolin at gmail.com
Wed Dec 1 12:36:46 UTC 2010


On Tue, Nov 30, 2010 at 4:47 PM, Craig Sanders <cas at taz.net.au> wrote:
> no idea if Brent's problem is the same as mine or not, but i found a
> solution for the tuning & recording problems i've been having.
>
> On Mon, Nov 29, 2010 at 11:34:36PM -0500, Greg wrote:
>> On 11/29/2010 08:01 PM, Brent Bolin wrote:
>> > Nagging problem in log files.
>> >
>> > Continue to see these errors -
>> >
>> > 2010-11-29 18:30:04.016 ProgramInfo(1321_20101129183000.mpg), Error:
>> > GetPlaybackURL: '1321_20101129183000.mpg' should be local, but it can
>> > not be found.
>> > [..]
>> >
>> Any time I have had that happen to me,it was a failure of the
>> capture device to start up...
>
> there's more to it than capture card failure - i get the above errors
> consistenly but ONLY on certain channels (all of the SBS channels incl
> SBS ONE, SBS TWO, SBS HD, and all of the NINE channels 9, 99 GO, 90
> GEM).  All other channels are fine.
>
> (BTW my location is Melbourne, Australia - so all channels, frequencies,
> networkids etc mentioned below are for that region)
>
> this started on Sunday after i stopped all myth backends and ran
> myth-setup on the master to scan for new channels. all channels used to
> work before i scanned.
>
> i've examined a diff of the channel table and noticed that there are
> differences in some of the fields for several of the channels. e.g. for
> SBS ONE:
>
> fields:
>
> (`chanid`, `channum`, `freqid`, `sourceid`, `callsign`, `name`, `icon`, `finetune`, `videofilters`, `xmltvid`, `recpriority`, `contrast`, `brightness`, `colour`, `hue`, `tvformat`, `visible`,
> `outputfilters`, `useonairguide`, `mplexid`, `serviceid`, `tmoffset`, `atsc_major_chan`, `atsc_minor_chan`, `last_record`, `default_authority`, `commmethod`)
>
> the data below has been edited slightly for readability - spaces add to
> line up columns and the irrelevant icon field cleared to shorten the
> line.
>
> old data:
>
> (1003,'3','',  1,'SBS ONE','SBS ONE','',0   ,'','sbsone.shepherd.au',3,32768,32768,32768,32768,'Default',1,'',1,6,785,0,0,0,'2010-11-25 00:05:01','',-1);
>
> new data:
>
> (1003,'3','29',1,'SBS ONE','SBS ONE','',NULL,'','sbsone.shepherd.au',0,32768,32768,32768,32768,''       ,1,'',1,11,785,0,0,0,'2010-11-30 00:15:01','',-1);
>
> in particular, the freqid has changed from '' to '29', finetune has
> changed from 0 to NULL, and the mplexid has changed from 6 to 11.
>
> in two of the channels that still work fine (ABC1 & ABC2), the freqid
> has changed from '' to 12 but the mplexid is unchanged (4 in both).
>
> old:
> (1021,'21',''  ,1,'ABC1','ABC1','',0   ,'','abc1.shepherd.au',3,32768,32768,32768,32768,'Default',1,'',1,4,563,0,0,0,'2010-11-24 23:28:01','',-1);
> (1022,'22',''  ,1,'ABC2','ABC2','',0   ,'','abc2.shepherd.au',3,32768,32768,32768,32768,'Default',1,'',1,4,562,0,0,0,'2010-11-24 20:20:02','',-1);
>
> new:
> (1021,'21','12',1,'ABC1','ABC1','',NULL,'','abc1.shepherd.au',0,32768,32768,32768,32768,''       ,1,'',1,4,563,0,0,0,'0000-00-00 00:00:00','',-1);
> (1022,'22','12',1,'ABC2','ABC2','',NULL,'','abc2.shepherd.au',0,32768,32768,32768,32768,''       ,1,'',1,4,562,0,0,0,'2010-11-29 21:54:01','',-1);
>
>
> it looks like the mplexid has been renumbed along with the scan....so if
> i compare the old and new records in the dtv_multiplex table, the old mplexid
> 6 looks very different to the new mplexid 11.
>
> (`mplexid`, `sourceid`, `transportid`, `networkid`, `frequency`, `inversion`, `symbolrate`, `fec`, `polarity`, `modulation`, `bandwidth`, `lp_code_rate`, `transmission_mode`, `guard_interval`,
> `visible`, `constellation`, `hierarchy`, `hp_code_rate`, `mod_sys`, `rolloff`, `sistandard`, `serviceversion`, `updatetimestamp`, `default_authority`)
>
> old (no longer exists in the current mythconverg db):
>
> (6, 1,784,12802,536625000,'a',NULL,NULL,NULL,NULL,'7','1/2','8','1/8',0,'qam_64','n','2/3','1',NULL,'dvb',1 ,'2009-11-17 21:50:44','');
>
> new:
> (11,1,864,12802,536500000,'a',NULL,NULL,NULL,NULL,'7','2/3','8','1/8',0,'qam_64','n','2/3','1',NULL,'dvb',33,'2008-08-06 07:52:38','');
>
>
> searching the table for sourceid=784, there is another record that is almost identical to the old mplexid 6:
>
> (16,7,784,12802,536625000,'a',NULL,NULL,NULL,NULL,'7','1/2','8','1/8',0,'qam_64','n','2/3','1',NULL,'dvb',3,'2009-04-10 11:25:41','');
>
>
> if i run "update channel set mplexid=16 where chanid=1003;" in mysql
> then I can now tune in to SBS ONE for both Live TV and Recordings.
>
> similarly, "update channel set mplexid=16 where mplexid=11;" allows
> me to watch & record ALL of the SBS channels:
>
> mysql> select chanid,callsign,mplexid from channel where mplexid=16;
> +--------+----------+---------+
> | chanid | callsign | mplexid |
> +--------+----------+---------+
> |   1003 | SBS ONE  |      16 |
> |   1032 | SBS TWO  |      16 |
> |   1033 | SBS 3    |      16 |
> |   1034 | SBS 4    |      16 |
> |   1030 | SBS HD   |      16 |
> +--------+----------+---------+
>
> so, that tells me that there's something quite wrong with the scan
> channels function in mythtv-setup. at a guess, it is choosing the first
> mplexid for a given networkid so if the table has old data in it as well
> as new (e.g. if the transportid or frequency or something changes) it
> will choose the OLD data. maybe it should 'ORDER BY updatetimestamp DESC
> LIMIT 1'
>
>
>
> on an immediate practical level, it also tells me that if i find out
> what the mplexid for the the NINE channels should be, i should be able
> to fix it....
>
> [10 mins later]
>
> well, that didn't quite work for NINE. the dtv_multiplex table has two
> entries for networkid=12829, and they're both exactly the same except
> for updatetimestamp. and they're the same in the current table and in
> the mysql backup data.
>
> however, the backup data had another record in dtv_multiplex for
> frequency=191625000 which was completely missing in the current table.
> the only difference is that the networkid has changed from 12829 to
> 4114.
>
> in old and new dtv_multiplex table:
>
> (2 ,1,1072,12829,191625000,'a',NULL,NULL,NULL,NULL,'7','3/4','8','1/16',0,'qam_64','n','3/4','1',NULL,'dvb',24,'2009-04-10 09:06:40','');
> (13,7,1072,12829,191625000,'a',NULL,NULL,NULL,NULL,'7','3/4','8','1/16',0,'qam_64','n','3/4','1',NULL,'dvb',24,'2009-04-10 11:24:31','');
>
> only in old dtv_multiplex table:
>
> (17,1,1072,4114 ,191625000,'a',NULL,NULL,NULL,NULL,'7','3/4','8','1/16',0,'qam_64','n','3/4','1',NULL,'dvb',24,'2009-11-17 21:50:29','');
>
>
> which begs the questions - why did this record get deleted from the
> dtv_multiplex table?  and why didn't the channel scan in mythtv-setup
> pick up the networkid 4114?
>
> anyway, "update dtv_multiplex set networkid=4114 where networkid=12829;"
> fixes the NINE channels.  I can now watch and record channel 9, 90, and
> 99.
>
>
> one final question is: is there a safe way of clearing *ALL* channel scan
> data and forcing a complete scan from scratch?
>
> is it as simple as 'delete from channel', 'delete from dtv_multiplex',
> 'delete from channelscan_dtv_multiplex' and then running mythtv-setup to
> scan? or will that bugger up other things?
>
> craig
>
> --
> craig sanders <cas at taz.net.au>
> _______________________________________________
> mythtv-users mailing list
> mythtv-users at mythtv.org
> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>

Other anomalies that I don't understand


2010-12-01 00:37:02.764 ProgramInfo(1021_20101201003700.mpg), Error:
GetPlaybackURL: '1021_20101201003700.mpg' should be local, but it can
not be found.
2010-12-01 00:37:03.161 TVRec(1): rec->GetPathname():
'/var/lib/mythtv/xen/recordings/1021_20101201003700.mpg'

Not sure what's going on here.  So it almost looks like it's checking
a filename or the availability of the location/filename.  The
recording is there and usable by the front ends.


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