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Choppy playback 1080i50 on 1080p50 with deinterlacing.

Posted: 02 Jun 2015 09:03
by sheppai
Hi.

I have a problem that I can't fix and don't understand why it is happening. I have multicast IPTV stream and I like to watch sports on my PC when the TV (with STB) is occupied. The stream is 1080i50 or 576i50 (I live in PAL area). I have a monitor that supports 1080p50. If I setup VLC to deinterlace with Linear mode, I get super smooth playback just like on TV. This, however, doesn't last. After some random time, which can be a minute or sometimes an hour, the playback gets choppy for no apperent reason. My CPU is Intel® Core™ i3-2310M CPU @ 2.10GHz × 4 and VLC uses ~80 % (measured in Linux, where max is 400 % because of 4 logical cores) if I playback 1080i50 stream and 44 % if I playback 576i50 stream. The CPU usage doesn't change when the playback get choppy, I am running nothing besides VLC. The problem is the same if I run VLC in Linux or Windows. I even tried it on another PC with different CPU (AMD Athlon X2 4000+) and the result is the same.
The problem never occurs if my monitor is set to 1080p60. Then the playback stays choppy the same amount throughout time. Choppy ofcourse because 50 fps displayed on 60 Hz... but it never gets worse.
I have also tried to connect my PC to my TV and I set the output to 1080i50 so the stream doesn't have to be deinterlaced by VLC and the same happens. After some random time the super smooth playback becomes choppy.
I also tried to set my monitor to 576p50 and 720p50 and the issue is the same.
To resolve the issue that occurs, I have to close VLC and reopen it. Then it is smooth again for a random time.

Any suggestions?

Things I have already tried:
- different Video Settings Output
- Accelerated video output (Overlay) ON and OFF
- Hardware-accelerated decoding Disable and VAAPI on Linux and DXVA2 on Windows
- Video quality post-processing level 0 through 6
- Skip H.264 in-loop deblocking filter all options (yes, my stream is H.264)
- Clock synchronisation Default, Enable and Disable
- Direct rendering ON and OFF
- Error resilience 0 through 4
- Workaround bugs 0 and 1
- Hurry up ON and OFF
- Allow speed tricks ON and OFF
- Threads 0 throgh 4

Nothing resolved the issue, in fact, it stayed completely the same. No change regarding smoothness/choppyness, only differences in picture quality, with some setttings not even that.

Re: Choppy playback 1080i50 on 1080p50 with deinterlacing.

Posted: 05 Jun 2015 10:54
by sheppai
OK, now I have found two samples that have the same problem for me.
Sometimes, if I'm lucky, VLC plays them both super smooth, sometimes they already begin choppy.

Could it be that it's a VSYNC issue?

http://solidrun.maltegrosse.de/~fritsch ... _mbaff.mp4
http://solidrun.maltegrosse.de/~fritsch/burosch1.mpg

I will try with MPC-HC/MPC-BE later on as I have heard those handle VSYNC well and will report back...

Re: Choppy playback 1080i50 on 1080p50 with deinterlacing.

Posted: 06 Jun 2015 14:54
by sheppai
MPC-HC and MPC-BE both play the stream perfectly. Smooth all the way, even after 2 hours...
Unfortunately that can be a solution for me only in Windows, for Linux I am still hoping I can somehow resolve this with VLC.

Re: Choppy playback 1080i50 on 1080p50 with deinterlacing.

Posted: 07 Jun 2015 10:04
by sheppai
Although I am only talking to myself on this forum ;) ;) ;), I will post another thing...
I have finally solved all my problems. I found this awesome thing called kodi, previously xbmc. It just plays back smoothly everything you throw at it! And it is available for all OSes I use.
VLC is still great, but I just can't use it for the things described in my previous posts...

Re: Choppy playback 1080i50 on 1080p50 with deinterlacing.

Posted: 16 Jul 2015 17:21
by Jean-Baptiste Kempf
Activate hardware decding.