Sound but no image after tuning on TV channel (1 Viewer)

[Stéphane Lenclud]

Guys, you lost me somewhat
Thanks the both of you for your input though.
I did not know I could use CyberLink codecs. Since I own a PowerDVD 14 license I thought I may as well put them to good use.
I found the following instructions and that worked just fine for me.
http://wiki.team-mediaportal.com/1_...ration/9_Codecs_and_Renderer/PowerDVD_Decoder

Checking CPU usage I can easily tell LAV is using more demanding on the CPU than CyberLink or MS. Since it's not using hardware acceleration it makes sense.
On my setup MP remains below 10% CPU with LAV and below 4% with CyberLink.

Let's see if that no video issue is still happening when not using Microsoft codecs.

I also noticed I have a stuttering issue on live TV and TS files see:
https://forum.team-mediaportal.com/threads/dropping-frames-when-watching-live-tv.133080/

 

[mm1352000]

Guys, you lost me somewhat

Sorry about that. At this time the only suggestion I have for you is still to try other video codecs and/or try disabling/enabling DXVA.

Checking CPU usage I can easily tell LAV is using more demanding on the CPU than CyberLink or MS. Since it's not using hardware acceleration it makes sense.
...
On my setup MP remains below 10% CPU with LAV and below 4% with CyberLink.

LAV does support using hardware acceleration for video decoding. It's completely configurable from within the LAV video settings, as shown here:

The CPU usage numbers that you quoted indicate both Cyberlink and LAV are using hardware acceleration (DXVA). One implementation can be more efficient than another.


[Aside...
@HTPCSourcer
One reason LAV DXVA might not be working on HTPC 1 is if you have accidentally unticked H.264 and/or MPEG-2 for eiither/both of SD and HD under "codecs for HW decoding". Those sorts of settings are worth checking.
]

 

[HTPCSourcer]

One reason LAV DXVA might not be working on HTPC 1 is if you have accidentally unticked H.264 and/or MPEG-2 for eiither/both of SD and HD under "codecs for HW decoding".

It's all ticked.

So I switched h.264 decoding once again to LAV in the MP Config and started HD TV. The CPU load was then oscillating between 75 and 100%, however, the picture remained watchable at this time. I can see the hardware decoding being active with 'dxvan' displayed in the LAV config screen.

I then switched back to MS-DTV. The CPU load dropped as expected - but only a little bit - and was somewhere at 60-70%. Restarting MP did not change this, but after a reboot the CPU load with MS-DTV was down again to 20%.

 

[mm1352000]

I then switched back to MS-DTV. The CPU load dropped as expected - but only a little bit - and was somewhere at 60-70%. Restarting MP did not change this, but after a reboot the CPU load with MS-DTV was down again to 20%.

Now that is bizarre! I've never read of any situation like that before.

 

[HTPCSourcer]

Now that is bizarre! I've never read of any situation like that before.

It certainly is. Let me add some more to the bizzare:

As discussed LAV is used for MPEG2 on this particular system. So when I play SD channels, after some time it can be noticed that audio and video are getting asynchronous. The lag increases over time and if kept playing will eventually lead to the picture getting choppy. Jumping a few seconds back and forth again in buffer restores the synchronicity. The issue is restricted to SD channels and to this system only. It did not exist under WIn 7 when SD was also using MS-DTV.

I never reported this, partly because there was more urgent stuff, and also because I rarely watch SD, but mainly becasue it is not happening 100% of the time. So whenever I wanted to reproduce the problem to be able to gather logs, I was not able to get the effect. The synchronicity problem appears worst on channel Vox and Super RTL. Both channels belong to the same media group (RTL) and are braodcasted on the same transponder.

Micosoft sells a Win 10 DVD Player app for 15 EUR. If I had certainty that this would restore the mpeg2 codecs on the system, it might be worth spending the money rather than chasing ghosts.

 

[mm1352000]

It certainly is.

After a couple of hours of thinking, I've been wondering if it's possible that you're running into thermal limits (=> GPU throttling => DXVA disabled)?

As discussed LAV is used for MPEG2 on this particular system. So when I play SD channels, after some time it can be noticed that audio and video are getting asynchronous. The lag increases over time and if kept playing will eventually lead to the picture getting choppy. Jumping a few seconds back and forth again in buffer restores the synchronicity. The issue is restricted to SD channels and to this system only. It did not exist under WIn 7 when SD was also using MS-DTV.

This (or similar) is something I've seen before, including on my own system. Such behaviour/results can be triggered/caused by stream corruption. Different codecs respond to corruption in different ways.

I never reported this, partly because there was more urgent stuff, and also because I rarely watch SD, but mainly becasue it is not happening 100% of the time. So whenever I wanted to reproduce the problem to be able to gather logs, I was not able to get the effect. The synchronicity problem appears worst on channel Vox and Super RTL. Both channels belong to the same media group (RTL) and are braodcasted on the same transponder.

All this is consistent with stream corruption, possibly due to rare short signal glitches on that particular transponder.

 

[HTPCSourcer]

After a couple of hours of thinking, I've been wondering if it's possible that you're running into thermal limits (=> GPU throttling => DXVA disabled)?

It's a standard setup, i.e. CPU with cooler and fan. But it never harms to take a look at the system's physical condition at this moment.

All this is consistent with stream corruption, possibly due to rare short signal glitches on that particular transponder.

Nothing one can do about this other than changing codec.

 

[Sebastiii]

Hi,

Not related to TV but i run into desync too when playing a serie because the video kind of made pause between act1 and 2 (in TV serie we have most 3 or 5 chapters/act, i call it that way).
I'm was running MPAR too but i kept this file because it can be useful for making debugging for either LAV or MPAR or what ever.

If it's LAV related, i just need to be sure that i can reproduce it outside of MP first