DVB-S TV "Detected FPS" fluctuating, causing stuttering (1 Viewer)

[LMKz]

Have just installed MediaPortal and finding it very good, but a couple of quirks.

I am in New Zealand, using a Nova-S-Plus DVB-S PCI card to receive satellite Freeview (Optus D1). Most channels work fine, but a couple (TV1, TV2) have a weird issue with a lot of stuttering. When I do the "!" thing to bring up on-screen deubg info, I can see that the "DETD FPS" value is constantly fluctuating between 50 and 25 FPS. As it moves between the two a lot of stuttering occurs. The "REPT FPS" value is a constant 50FPS (reported?). It seems to drop into 25FPS when there is not much movement on the screen, for example during the news when newsreader just talking to the camera. When an action shot comes on, it jumps up to 50FPS.

Other channels (TV3, for example) work fine, and stay a constant 50FPS.

Any ideas?? Is there a way to force MP to use the Reported value? Does Dynamic Refresh Rate have any influence on this? Is it a TV server thing, or a MP thing?

Thanks

 

[LMKz]

Just ran in debug mode to get log, see attached. For the 30 seconds or so I was watching TV it jumped back and forward between 25 and 50 FPS. This time I ran Mediaportal on my main PC, connected to separate TV server. Exactly the same symptoms as when running Mediaportal connected to TV on TV-server box.

Can anyone help? Can prob. capture a video and upload to Youtube if that would be useful to diagnose...

Thanks

 

[Owlsroost]

It sounds like those channels are using variable field/frame encoding (like the Freeview HD channels here in the UK) - this seems to upset MS DTV and PDVD decoders, causing stuttering after the transitions while they adapt to the new field/frame rate.

Try using LAV filters 0.51.3 for TV - http://forum.doom9.org/showthread.php?t=156191 - and tick the 'Aggressive Deinterlacing' box in the video decoder settings (and select 'DXVA2 Native' in the 'Hardware Acceleration' section)

Tony

 

[LMKz]

OK that (LAV filters) works great at fixing up those channels that were flip/flopping frame rate. Thanks.

BUT now I am getting regular dropped frames on other channels, and one channel causes MP to hang with black screen.

Any other thoughts??

Getting frustrated with this system, was hoping it would "just work".

Lachlan

 

[Owlsroost]

Is there any common factor in the 'problem' channels - are they all SD/HD/MPEG2/H264 etc ?

Your system (Q6600 + HD 4670 ?) should be powerful enough to cope with anything....

You could try 'TsReader_noStopMod59c' from https://forum.team-mediaportal.com/threads/experimental-tsreader-development.102693/#post-811296 - this *may* fix the black screen problem.

Tony

 

[mm1352000]

Everything is MPEG 2 SD. The bitrates are relatively low - some around 2 Mbps. They're using every tweak possible to squeeze as many channels as they can into two ~30 Mbps transponders.

[Edit: the TV 3/FOUR/C4/TV 3 + 1/Prime transponder now has 12 TV channels! The other one "only" has 8.<sigh>]

 

[Owlsroost]

Everything is MPEG 2 SD. The bitrates are relatively low - some around 2 Mbps. They're using every tweak possible to squeeze as many channels as they can into two ~30 Mbps transponders.

[Edit: the TV 3/FOUR/C4/TV 3 + 1/Prime transponder now has 12 TV channels! The other one "only" has 8.<sigh>]

I was hoping someone from NZ would drop by eventually

Tony

 

[LMKz]

Thanks for looking into this guys.

Q6600 that recorded log was being used as client to remote TV server. The actual HTPC box is brand new Sandy Bridge Pentium G630 with (not so new) HD 3450 card. So I doubt hardware is the problem. Looking in Process Explorer while Tv is running, there is not much happening on CPU or GPU.

I think the "black channel" may be a red herring (C4), as didn't work even when I switched back to MS decoder yesterday. Maybe that channel was on the blink; haven't tried it today.

Being a .Net dev by trade, I downloaded the MP source for a poke around, but rapidly got lost. I guess this issue is outside MP anyway.

Any other help appreciated.

Lachlan