[mythtv-commits] Ticket #3640: mythtv-setup stores incorrect transport frequencies (DVB-C)

[MythTV]

#3640: mythtv-setup stores incorrect transport frequencies (DVB-C)
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 Reporter:  anonymous    |        Owner:  janne
     Type:  defect       |       Status:  new  
 Priority:  minor        |    Milestone:  0.21 
Component:  channelscan  |      Version:  head 
 Severity:  low          |   Resolution:       
  Mlocked:  0            |  
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Comment(by klaas.de.waal at gmail.com):

 In bug #1866 the DVB-C scanning problem is described as:[[BR]]

 ''Each TS contains several NIT-Others as well as invalid NIT-Actual (NIT-
 Actual present but effectively not used - Each NIT-Other describes the
 valid setup for a particular geographical area (and is identified by a
 different network-id) - the original network-id is the same on all TS.
 This is the network setup of @home, casema and Multikabel in NL.
 ''[[BR]]

 This description of the problem is correct for the @home network in the
 Netherlands where I live. There are a large number of different cable
 network regions in the Netherlands and they all have different
 frequencies, but the digital signals are exactly the same
 everywhere.[[BR]]
 The digital signal has a number of different network information tables,
 one for each region.
 However, there is no way you can find out the actual network ID for your
 own region automatically.[[BR]]
 This is also true for commercial DVB-C set-top-boxes such as my Samsung
 box; when you take a subscription for the digital TV service you get a
 piece of paper with the network ID
 and the initial frequency, and with this information your DVB-C set-top-
 box can do a service scan.

 I have made a patch for libs/libmythtv/mpeg/dvbstreamdata.cpp in which it
 searches for a user-defined network ID, in my case hardcoded to 1111.
 This works OK. The way to get all channels is now:[[BR]]
 (1) Do one "full scan" for a single frequency. After this the
 dtv_multiplex table has all the correct frequencies.[[BR]]
 (2) Then do a "scan all transports" and then you have found all services.
 The attached patch is for version 0.20.2 but I have also tested this with
 a svn15604 (end of january).[[BR]]
 N.B. The network ID stored in dtv_multiplex is still 1000. This does not
 hurt.

 Instead of using a hard-coded network ID a better way is to add an option
 to MythTV to let the user specify the network ID for DVB-C networks, and
 store this somewhere in the MySQL database.
 I think the best place for the user-defined network ID is in the
 videosource table.
 I have made some testcode to do just that; I'm currently stuck at what is
 the best way to get the value of the user-defined network ID from
 videosource table in the MySQL database into the dvbstreamdata.cpp code.
 Suggestions are most welcome.

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Ticket URL: <http://svn.mythtv.org/trac/ticket/3640#comment:33>
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