[mythtv-users] trouble with nvidia and bob x2 deinterlacing

Wed Mar 19 20:13:27 UTC 2008

On 19/03/2008, Inor Kuo <inorkuo at hotmail.com> wrote:
>
>
>
>  >> I have searched for and read every thread I could find on bob deinterlacing
>  >> but I am still experiencing significant shaking or jitter when using bob x2
>  >> with sd and hd recordings (NTSC). Originally I was using a modeline I found
>  >> in the mythtv wiki for my tv and the refresh rate came out to just under 60
>  >> so myth wouldn't use bob x2. In my reading I had come across threads where
>  >> people suggested using xvidtune to adjust the modeline so that the refresh
>  >> rate was just over 60.
>  >>
>  >> Modeline from wiki "1368x768 at 85" 85.50 1368 1414 1526 1798 768 771
>  >> 777 795 +hsync –vsync
>  >>
>  >> Modeline tweaked "1368x768 at 85" 85.50 1368 1400 1720 1792 768 783 791
>  >> 795 +hsync –vsync
>  >>
>  >> Xvidtune wouldn't let me adjust on the fly so I used a modeline calculator
>  >> http://xtimingsourceforge.net/cgi-bin/xtiming.pl and put in
>  >> my tv's specs and made adjustments until the refresh rate was over 60.
>  >> after a reboot with my tweaked modeline in xorg.conf, xvid showed the
>  >> following.
>  >>
>  >> Pixel Clock: 85.50 MHz
>  >> Horizontal Sync: 47.71 kHz
>  >> Vertical Sync: 60.02 Hz
>  >>
>  >> My tv is a Vizio 50" Plasma that I got from Costco about almost 2 years ago.
>  >> The specs from the manual are as follows.
>  >>
>  >> Resolution Refresh (Hz) H.Freq (kHz) V.Freq (Hz) H.Sync V.Sync Pixel Freq (MHz)
>  >> 1366x768  60               47.7             60.00          P         N         85.500
>  >>
>  >> At this point, myth let me use bob x2 but like another user reported here
>  >> http://www.gossamer-threads.com/lists/mythtv/users/310039?do=post_view_threaded#310039,
>  >> it looked like there was an earthquake going on, moreso for sd than hd
>  >> recordings.
>  >>
>  >> I am running mythtv version 0.21 compiled from source on Ubuntu 7.10 Gutsy
>  >> with an onboard Nvidia GeForce 6150 gpu using nvidia driver version 169.12,
>  >> 1gb of ram, 2gb of swap, and an Amd Athlon 64 X2 Dual Core 4200+ processor.
>  >> The plasma tv is connected to the computer via vga.
>  >>
>  >> Nvidia settings
>  >> 0/OpenGLImageSettings=1
>  >> 0/XVideoTextureSyncToVBlank=1
>  >> 0/XVideoBlitterSyncToVBlank=1
>  >> 0/XVideoSyncToDisplay=1
>  >>
>  >> In mythfrontend, I have "enable OpenGL vertical sync for timing" checked.
>  >>
>  >> I have a total of 3 combined frontend backend machines and I tried getting
>  >> bob x2 to work on the other two as well with the same shaky results.
>  >>
>  >>             Monitor                                GPU Nvidia          Driver Version     Processor
>  >> Setup 1 50"P50HDTV Vizio Plasma onboard nvidia 6150 169.12 AMD64X2 DC 4200+2.2ghz
>  >>
>  >> Setup 2 42"GV42L Vizio LCD TV     onboard nvidia 6150 1.0.9639 AMD64X2 DC 3800+2.0ghz
>  >>
>  >> Setup 3 19"Samsung 920NW LCD nvidia geforce 7300LE 100.14.19 Intel C2D 6420 2.13ghz
>  >>
>  >> On all 3 machines I had to adjust the modelines to get the refresh rate
>  >> above 60 using the native resolutions of the screens (although 1368x768 was
>  >> the closest I could get to 1366x768 for the 2 vizio's).
>  >>
>  >> I've read that there is some jitter to be expected with bob x2 enabled but
>  >> what I am seeing is unwatchable for sd recordings. It's better on hd
>  >> recordings but it gives you a headache after a while.
>  >>
>  >> I would really like to get bob working correctly but I am fairly new to all
>  >> of this deinterlacing and refresh rate stuff. I feel that I have done as
>  >> much as I can on my own and at this point I don't know what else to do so
>  >> I'm turning to the community for help. If anyone can offer any suggestions
>  >> it would be greatly appreciated.
>  >
>  >
>  >
>  > Inor,
>  >
>  > You're probably on the right track... I suggest you take one box and
>  > do a scientific approach only changing one setting at a time.
>  >
>  > First of all you need to get some debugging going however:
>  >
>  > mythfrontend -v playback>/tmp/frontendlog 2>&1
>  >
>  > should provide you with some nice logs.
>  >
>  > Check that you are indeed using bob deinterlace (it'll say so in the
>  > logs). That myth has recognized the refresh rate correctly etc...
>  >
>  > My personal idea is that you might need to turn off "enable OpenGL
>  > vertical sync for timing" .
>  >
>  > Cheers
>  >
>  > Steve
>
>
> Logfile #1
>
>
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Inor,

Ok I'm not too up on 1080i playback (I only have SD). And frankly
that's probably pushing the envelope, but looking at log #1 you might
want to look at:

2008-03-19 14:24:55.305 nVidiaVideoSync: VBlank ioctl did not work,
unimplemented in this driver?
2008-03-19 14:24:55.305 DRMVideoSync: Could not open device
/dev/dri/card0, No such file or directory
2008-03-19 14:24:55.305 RTCVideoSync: Could not set RTC frequency,
Permission denied.
2008-03-19 14:24:55.306 Set video sync frame interval to 33366
2008-03-19 14:24:55.309 Using audio as timebase
2008-03-19 14:24:55.309 Video timing method: USleep with busy wait

It indicates that it is using USleep as the timing method which is
generally considered not or good especially as it couldn't set the RTC
frequency. Have a look at the wiki (search for RTC I think), to see if
you can get better than this....

BTW your TV is 1080i right?

Cheers

Steve