Extremely slow channel switching

[polosat]

Hello!

 

I use recording services to watch cable TV via VLC media player.

 

The problem is switching between channels which never takes less than 15 - 20 seconds.

 

But, when I use DVBViever channels are switching very quickly: no more than 1 - 2 seconds (BTW, that's fantastic!).

 

So, what can be a problem?

 

The most of my channels are encrypted, so I use the TV-tuner with CAM module.

I noticed, that switching to an unencrypted channel is quick enough, but to an encrypted - extremely slow. (in DVBViewer no delays at all on the same channels)

 

Here is a piece of svcdebug.log file at the time when I switched a channel:

 

28.12.12 01:46:00.730 tStreamClient Release anysee BDA Digital Tuner(DVB-C)
28.12.12 01:46:00.730 tStreamClient Destroy anysee BDA Digital Tuner(DVB-C)
28.12.12 01:46:01.211 tStreamClient Destroyed anysee BDA Digital Tuner(DVB-C)
28.12.12 01:46:01.212 tStreamClient hamDeleted anysee BDA Digital Tuner(DVB-C)
28.12.12 01:46:01.212 ReleaseStandbyblock TStreamClient
28.12.12 01:46:01.212 SetThreadExecutionState 0x80000000
28.12.12 01:46:01.212 Releasereference TStreamClient: 0
28.12.12 01:46:01.212 SetStandbyblock  TStreamClient
28.12.12 01:46:01.212 SetThreadExecutionState 0x80000041
28.12.12 01:46:01.212 AddReference     TStreamClient: 1
28.12.12 01:46:02.222 TBDAAnysee.Opendevice bvAnysee
28.12.12 01:46:02.222 tStreamClient AllocateHardware anysee BDA Digital Tuner(DVB-C)
28.12.12 01:46:02.222 TBDAAnysee.SetTuner TType: 0, Freq: 314000, Symrate: 6875, LOF: 0, Tone: 0, Pol: 3, DiseqC: 0, FEC: 0, APID: 210, VPID: 201, PMT: 200, SID: 7, SatMod: 0, DiseqCVal: 0, NID: 5910, Flags: 25
28.12.12 01:46:02.502 TBDACIAnyseeModule CI Base SetTuner Entering
28.12.12 01:46:02.502 TBDACIAnyseeModule CI Base SetTuner Leaving
28.12.12 01:46:02.502  AllocateHardware anysee BDA Digital Tuner(DVB-C)
28.12.12 01:46:02.503 TAnyseeCam WM_ANYSEE_CI_STATES State: 2101
28.12.12 01:46:02.623 TBDACIAnyseeModule WinProc Received PMT ready
28.12.12 01:46:05.153  Release         anysee BDA Digital Tuner(DVB-C)
28.12.12 01:46:11.002 TAnyseeCam WM_ANYSEE_CI_STATES State: 2102
28.12.12 01:46:11.077 TBDACIAnyseeModule evalPMT Sid: 7 Result: 1
28.12.12 01:46:15.047 TAnyseeCam WM_ANYSEE_CI_STATES State: 2105
28.12.12 01:46:15.141 TAnyseeCam WM_ANYSEE_CI_STATES State: 2103

 

I push a button at 01:46:00 and only at 01:46:15 I see the channel switched.

support.zip

Edited December 27, 2012 by polosat

[mague]

UPnP switching is much slower then native channel switching. There is maybe some room for improvement, but i doubt UPnP will ever come close to native switching.

[polosat]

Of course, I understand this.

Native switching operates just with API calls. Most of operations take milliseconds, and the only bottleneck here is how quick the TV tuner hardware responds to these calls.

Sure, when we use the model "Recording service + network clients" it can't operate at the same speed, primarily because of conversions and handshaking at network layers, and problems with network bandwidth.

 

But IMHO difference in 15 - 20 seconds is too much for this.

 

The following facts confuse me in this situation:

 

1. The recording service and the client are located at the same machine.
   So, network bandwidth is not a problem here
    
   
2. DVBViewer in native mode switches channels extremely fast.
   So, no problems with the hardware.
    
   
3. In the "network mode" switching to FTA channels takes 1-2 seconds, but for encrypted channels it takes 15 - 20 seconds.
   So, in general, the "network mode" operates at the reasonable speed, but it seems "handshaking" with the CI module affects this somehow.
    
   
4. In the "native mode" DVBViewer takes 0,5 - 1 seconds switching to encrypted channels at the same transponder, and about 2 seconds when a new channel is on a different transponder.
   So, DVBViewer operates with CI module just fine
   

 

Looking at these facts I can conclude that the problem here is in how the recording service interacts with the hardware - CAM module in the TV tuner.

 

Probably I made some mistakes in configuration, but I didn't do anything special there.

Edited December 28, 2012 by polosat