Audio sync problems when screen set to 24 Hz (2 Viewers)

[happy]

well seeing as someone has made a break through

i was thinking could the renderer be doing something to cause high cpu usage i would give a suggestion but im not sure what - just a thought

also people have mentioned this problem with ati/nvidia chipsets, what about people with the intels chips do they suffer from it?

 

[rak]

For me I have this issue with MPC-HC codec. When I have changed it to CoreAVC 1.9.5, the sync problems disappeared. At least one movie is in sync now.

 

[jet70]

OK, I have now spent quite some time messing about with this and can confirm 2 issues which have been mentioned previously in this thread, but I belive are separate issues.

1) XVID audio synch delay. This appears to occur in 24hz mode and seems very difficult to pin down. It seems quite random. I can play one fine at one moment, but on other occasions, suffers slight audio delay.

My thoughts are that it is something to do with the refresh rate change somehow still taking hold whilst the video kicks in and the sound gets delayed somehow.

Although I need to test this more, I think this happens when cahanging from say my default of 50hz to 24hz and thenplaying the xvid. I think that if I am already playing at 24hz, that this doesn't seem to occur (or is much less likely to occur).

2) 24hz hidef mkv audio delay. This is much more aggressive delay and for me occurs using VISTA/EVR/ATI and MPC video decoder.

This does not occur where DXVA kicks in but for those that software decode using MPC.

I am unsure how to identify when DXVA is on except that my CPU runs at around 10% which is the indicator I have used.

The mkvs that cause the problens have a profile of 5.1 and ref frames of 8 or 9. The CPU does run high, but this also occurs when playing the same mkv in Graphedit using MPC.

In Graphedit, the audio does not suffer lag, so from what I can tell, MPC software decoding in 24hz causes audio delay in the Mediaportal player.

COREAVC does not cause audio delay but ofcourse is purely software.

The quick answer is to ensure that the profile of one's mvv's is 4.0 or 4.1 with ref frames of up to 5, but this it does appear that MPC does behave outside of mediaportal when software decoding.

The xvid problem is more worrying because there is no workaround. I use ATI profiles via .bat file. I put a pause in this at the end for 3 seconds and thought that this had solved the issue, but I have since managed to get audio delay again. My default hz rate in Mediaportal is 50hz. I find thebest time to try and emulate this problem is by starting a 24fps xvid on entering Mediaportal.

I really hope some of this info is helpful!

 

[tourettes]

Unfortunately these test results are really confusing, so to make any real test data available for us (developers) I think we need to set up some test material that different people can test (with different HW and codecs), so we could finally get some good test results.

Any volunteers to gather different (non-copyrighted) H.264 video files with could be used as the testing material? If not then I'll just post pone the error to some future date (maybe the day when I see 24p capable display device on my front door )

 

[happy]

Unfortunately these test results are really confusing, so to make any real test data available for us (developers) I think we need to set up some test material that different people can test (with different HW and codecs), so we could finally get some good test results.

Any volunteers to gather different (non-copyrighted) H.264 video files with could be used as the testing material? If not then I'll just post pone the error to some future date (maybe the day when I see 24p capable display device on my front door )

the big buck bunny movie, its free on the website 700mb download 10 minutes long should be enough time to catch out of sync issues

 

[jet70]

Anyone know of any non copyrighted xvids since I reckon this might be easier to fix than the x264 issue, if people are able to look into it!

 

[tourettes]

Anyone know of any non copyrighted xvids since I reckon this might be easier to fix than the x264 issue, if people are able to look into it!

You can always convert between the different video formats, so xvid could be made from that Big Buck Bunny clip (of cource someone needs to be able to host that file...)

 

[Rayures]

Grabbed the h264 1080p Big Buck movie, will help where possible with testing....

 

[tourettes]

Few more free sample movies would be required. After that I'll open a new forum topic for the testing results (I really hope that all who are going to participate in the testing will follow the exact steps ).

 

[Rayures]

well... there are some clips on H.264 Demo Clips H264info.com