[mythtv-users] VDPAU playback issues

Sun Nov 4 01:43:36 UTC 2012

I'm experiencing some glitching on a few videos and I'm having trouble sorting it out. Running 0.26 on an atom/ION box on kernel 3.2 (mythbuntu 12.04), using the VDPAU High Quality playback setting.

I've gone through the wiki entry on glitch-free playback and inserted all the ModeLines into my xorg.conf as described, but things still aren't quite right.

Here's some log output from mythfrontend -v playback on an mkv file (x264/AC3 audio). I'm downmixing 6 channel audio to stereo.

2012-11-04 01:14:26.634266 I  AFD: Stream #0, has id 0x0 codec id H264, type Video, bitrate 0 at 0xcf31740
2012-11-04 01:14:26.644142 I  AFD: Selected FPS is 23.976 (avg 23.976 codec 23.976 container 1000 estimated 23.976)
2012-11-04 01:14:26.644215 I  Player(0): SetFrameInterval ps:1 scan:3
2012-11-04 01:14:26.644285 I  Player(0): detectInterlace(Detect Scan, Interlaced Scan, 23.976, 720) ->Progressive Scan

2012-11-04 01:14:26.644339 I  AFD: Using vdpau for video decoding
2012-11-04 01:14:26.644360 I  AFD: Looking for decoder for H264
2012-11-04 01:14:26.644970 I  AFD: Opened codec 0xcf31920, id(H264) type(Video)
2012-11-04 01:14:26.645064 I  AFD: Stream #1, has id 0x0 codec id AC3, type Audio, bitrate 448000 at 0xcc807c0
2012-11-04 01:14:26.645090 I  AFD: codec AC3 has 6 channels
2012-11-04 01:14:26.645110 I  AFD: Looking for decoder for AC3
2012-11-04 01:14:26.646601 I  AFD: Opened codec 0xcf31d00, id(AC3) type(Audio)
2012-11-04 01:14:26.646810 I  AO: Opening audio device 'hdmi:CARD=NVidia,DEV=0' ch 2(6) sr 48000 sf signed 32 bit reenc 0

2012-11-04 01:14:26.839834 I  VDP: SetVideoRenderer(vdpau)
2012-11-04 01:14:26.839861 I  VDP: SetVideoRender(vdpau) == GetVideoRenderer()
2012-11-04 01:14:26.841953 I  Trying to match best refresh rate 23.976Hz
2012-11-04 01:14:26.842011 I  Trying 1920x1080 23.976 Hz
2012-11-04 01:14:26.844032 I  Dynamic TwinView rate found, set 23.9758Hz as XRandR 57

This is my first observation: I've got a ModeLine for 1920x1080 at 23.976. So why is it saying it's using a Dynamic Twinview rate at 23.9758?

2012-11-04 01:14:27.261016 I  VDPAU: Information NVIDIA VDPAU Driver Shared Library  295.40  Thu Apr  5 21:54:31 PDT 2012
2012-11-04 01:14:27.261041 I  VDPAU: HQ Scaling not supported.
2012-11-04 01:14:27.261063 I  VDPAU: MPEG4 hardware acceleration not supported.

My second observation: Why is it saying MPEG4 hardware acceleration not supported? I'm pretty sure that the chipset in this box does MPEG4 acceleration.

2012-11-04 01:14:27.901087 I  VDP: GetFilteredDeint() : vdpau -> 'vdpauadvanceddoublerate'
2012-11-04 01:14:27.929986 I  VidOutVDPAU: Enabled deinterlacing.
2012-11-04 01:14:27.930154 I  VSYNC: DRMVideoSync: Could not open device /dev/dri/card0, No such file or directory
2012-11-04 01:14:27.930260 E  Player(0): Video sync method can't support double framerate (refresh rate too low for 2x deint)
2012-11-04 01:14:27.953072 I  VDP: GetFilteredDeint(vdpauadvanced) : vdpau -> 'vdpauadvanced'
2012-11-04 01:14:27.985325 I  VidOutVDPAU: Enabled deinterlacing.
2012-11-04 01:14:27.991046 I  Player(0): Video timing method: RTC
2012-11-04 01:14:27.991114 I  Player(0): Display Refresh Rate: 23.976 Video Frame Rate: 23.976

All sorts of things here that confuse me. Why is it enabling deinterlacing for a progressive scan video?
It now says the display refresh rate is 23.976 - but what about that XRandR mode it mentioned earlier? Is it not using that? (My TV doesn't have an info button to tell me what refresh rate is being used)

However I think the following shows probably what the real problem is:

2012-11-04 01:14:28.251288 I  Player(0): progressive frame seen after 2 interlaced frames
2012-11-04 01:14:28.251365 I  Player(0): A/V predict drop frame, dropping frame to catch up.
2012-11-04 01:14:28.251643 I  Player(0): Waiting for video buffers...
2012-11-04 01:14:28.285566 I  VDPAU: Added 2 output surfaces (total 4, max 4)
2012-11-04 01:14:28.392047 I  Player(0): Disabled deinterlacing
2012-11-04 01:14:28.395075 I  Player(0): Video is 4.08495 frames behind audio (too slow), dropping frame to catch up.
2012-11-04 01:14:28.395279 I  Player(0): Video is 5.29949 frames behind audio (too slow), dropping frame to catch up.
2012-11-04 01:14:28.395409 I  Player(0): Video is 5.95265 frames behind audio (too slow), dropping frame to catch up.
2012-11-04 01:14:28.395635 I  Player(0): Video is 6.19675 frames behind audio (too slow), dropping frame to catch up.
2012-11-04 01:14:28.395946 I  Player(0): Video is 6.13408 frames behind audio (too slow), dropping frame to catch up.
2012-11-04 01:14:28.396179 I  Player(0): Video is 5.83533 frames behind audio (too slow), dropping frame to catch up.
2012-11-04 01:14:28.396314 I  Player(0): Video is 5.35952 frames behind audio (too slow), dropping frame to catch up.
2012-11-04 01:14:28.396484 I  Player(0): Video is 4.7629 frames behind audio (too slow), dropping frame to catch up.
2012-11-04 01:14:28.396629 I  Player(0): Video is 4.06368 frames behind audio (too slow), dropping frame to catch up.
2012-11-04 01:14:28.396753 I  Player(0): Video is 3.28153 frames behind audio (too slow), dropping frame to catch up.
2012-11-04 01:14:28.396846 I  Player(0): Waiting for video buffers...
2012-11-04 01:14:29.654923 I  AFD: gopset not set, syncing positionMap
2012-11-04 01:14:29.654974 I  Dec: Resyncing position map. posmapStarted = 0 livetv(0) watchingRec(0)
2012-11-04 01:14:29.654998 I  AFD: Initial key frame distance: 15.
2012-11-04 01:14:31.824987 I  AFD: Key frame distance changed from 54 to 52.
2012-11-04 01:14:31.992106 I  Player(0): FPS:   25.41 Mean: 39351 Std.Dev: 17122 CPUs: 100% 100% 
2012-11-04 01:14:35.411139 I  AFD: Key frame distance changed from 52 to 86.
2012-11-04 01:14:35.953958 I  Player(0): FPS:   23.99 Mean: 41679 Std.Dev:   485 CPUs: 5% 5% 
2012-11-04 01:14:36.578591 I  AFD: Key frame distance changed from 86 to 28.
2012-11-04 01:14:38.706655 I  AFD: Key frame distance changed from 28 to 51.
2012-11-04 01:14:39.916859 I  Player(0): FPS:   23.99 Mean: 41690 Std.Dev:   691 CPUs: 12% 4% 
2012-11-04 01:14:41.750761 I  AFD: Key frame distance changed from 51 to 73.
2012-11-04 01:14:43.044159 I  AFD: Key frame distance changed from 73 to 31.
2012-11-04 01:14:43.878762 I  Player(0): FPS:   23.99 Mean: 41680 Std.Dev:   533 CPUs: 6% 3% 
2012-11-04 01:14:44.627999 I  Player(0): 400 progressive frames seen.
2012-11-04 01:14:45.587615 I  AFD: Key frame distance changed from 31 to 61.
2012-11-04 01:14:47.840684 I  Player(0): FPS:   23.99 Mean: 41680 Std.Dev:   487 CPUs: 6% 4% 
2012-11-04 01:14:49.550139 I  AFD: Key frame distance changed from 61 to 95.

The video plays very jerkily for the first 5 or 10 seconds then settles down. I've noticed the CPU usage is 100% according to this log during that time. What could be causing that?

Any observations or advice anyone can give will be greatly appreciated.

Thanks,

Mark