[mythtv-commits] Ticket #8731: DVB-T scan: muxes not tuned during full scan but tuned using NIT info

[MythTV]

#8731: DVB-T scan: muxes not tuned during full scan but tuned using NIT info
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 Reporter:  Nick Morrott <knowledgejunkie (at) gmail (dot) com>  |       Owner:  danielk   
     Type:  defect                                               |      Status:  new       
 Priority:  minor                                                |   Milestone:  unknown   
Component:  MythTV - Channel Scanner                             |     Version:  Trunk Head
 Severity:  medium                                               |     Mlocked:  0         
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 Using the same configuration as reported in #8726.

 Scan details: full UK scan using Sutton Coldfield transmitter with 6
 available muxes. Signal/tuning timeouts raised to 2000/6000ms. ALL
 services (DVB+MPEG) scanned, with decryption testing disabled.

 During the scan, a signal and successful lock is achieved on only 1 of the
 possible muxes (746000000), even when using doubled timeouts. The
 remaining 5 muxes are discovered in the NIT of this mux, and subsequent
 tuning of these muxes is successful.

 Checking the log output reveals the following for sample mux 634166670:

 i) During the initial full scan using default scan parameters, the
 following was seen:

 {{{
                         DVBChan(1:/dev/dvb/adapter102/frontend0): New
 Params: 634166670 auto 0 auto auto 8 a 1/32 n v fec: auto msys: UNDEFINED
 rolloff: 0.35
 2010-08-05 06:42:04.455 DVBChan(1:/dev/dvb/adapter102/frontend0): Tune():
 Frequency tuning successful.
 2010-08-05 06:42:04.455
 DTVSM(/dev/dvb/adapter102/frontend0)::SetChannel(-1, -1):
 2010-08-05 06:42:04.455 SM(/dev/dvb/adapter102/frontend0)::Start: begin
 2010-08-05 06:42:04.455 SM(/dev/dvb/adapter102/frontend0)::Start: end
 2010-08-05 06:42:04.504 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:04.504 SM(/dev/dvb/adapter102/frontend0)::RemoveFlags:
 Seen() Match() Wait(Pos,)
 2010-08-05 06:42:04.566 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:04.628 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:04.690 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:04.752 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:04.814 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:04.876 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:04.937 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:05.893 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:05.955 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:06.017 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:06.079 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:06.141 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:06.203 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:06.264 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:06.326 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:06.388 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:42:06.449 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 }}}

 No signal is seen within the 2000ms timeout value

 ii) Having extracted this sample mux's details from the NIT of the 1 mux
 locked to (746000000), the later "fill-in" scan was succesful:
 {{{
                         DVBChan(1:/dev/dvb/adapter102/frontend0): New
 Params: 634166670 qam_16 a 3/4 3/4 8 2 1/32 n v fec: auto msys: UNDEFINED
 rolloff: 0.35
 2010-08-05 06:45:51.455 DVBChan(1:/dev/dvb/adapter102/frontend0): Tune():
 Tuning to 634166670Hz
 2010-08-05 06:45:52.356 dvbchannel.cpp:wait_for_backend: Status:
 2010-08-05 06:45:52.356 DVBChan(1:/dev/dvb/adapter102/frontend0): Tune():
 Frequency tuning successful.
 2010-08-05 06:45:52.356
 DTVSM(/dev/dvb/adapter102/frontend0)::SetChannel(-1, -1):
 2010-08-05 06:45:52.356 SM(/dev/dvb/adapter102/frontend0)::Start: begin
 2010-08-05 06:45:52.356 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:45:52.356 SM(/dev/dvb/adapter102/frontend0)::Start: end
 2010-08-05 06:45:52.356 SM(/dev/dvb/adapter102/frontend0)::RemoveFlags:
 Seen() Match() Wait(Pos,)
 2010-08-05 06:45:52.420 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:45:52.481 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen() Match() Wait(Sig,)
 2010-08-05 06:45:52.510 DVBSM(/dev/dvb/adapter102/frontend0): UpdateValues
 -- Signal Locked
 2010-08-05 06:45:52.540 SM(/dev/dvb/adapter102/frontend0)::AddFlags:
 Seen(PAT,) Match() Wait()
 2010-08-05 06:45:52.540 ChannelScanSM(/dev/dvb/adapter102/frontend0): Got
 a Program Association Table for TransportID 4101
 }}}

 Is it possible to modify the default scan parameters in order to increase
 the likelihood of finding more/all muxes during the initial scan?

 Full log output of the scan is attached.

-- 
Ticket URL: <http://svn.mythtv.org/trac/ticket/8731>
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