[mythtv-users] Mythtv Internal Player Jitter/Jerky Video Playback When Playing ISOs

[Robert Macaulay]

On Sat, May 24, 2008 at 6:17 AM, CTD <ctd at minneapolish3.com> wrote:
>
> Hey there,
>
> When watching SD DVD iso images using mythvideo and the default Internal
> player, the video is choppy with jitter.  It is ever so slight when the
> scene is not panning, but still noticeable.  When the movie is panning
> across, the issue becomes much extremely evident.
>
> I do not think it is a frontend resource issue.  My frontend is an new
> AMD 64 Athlon 5300+, and the iso images are being accessed via a NFS
> share across a wired ethernet.
>
> I have been various posts which describe this, but I cannot seem to find
> any that offer a solution besides using mplayer or xine.
>
> Examples:
> http://www.gossamer-threads.com/lists/mythtv/users/139428#139428
> http://www.gossamer-threads.com/lists/mythtv/users/259164#259164
>
> Any ideas on what a solution is?  I am exploring using xine or mplayer.
> So far I have xine working except audio issues occur after watching the
> video for say 10 minutes or so.  Another thing to look into.
>

Resurrecting an older thread.

Also having the same problem still. Another thread that seems to hit is this
http://www.gossamer-threads.com/lists/mythtv/users/247511

The frontends are current systems, 0.21 + fixes. I've been logged into
them while the DVD is playing, and the cpu is never close to pegged.
The network has no bandwidth issues, all wired, no wireless.

Same setup as original poster. The ISO files are mounted over NFS.
This happens on both frontends. The main frontend is talking over
DVI->HDMI at 1920x1080 to a 1080p LCD, with overscaling turned off in
the TV. The other is over a VGA cable to a 1368x768 720p LCD(i think,
it's running the native resolution for a 720p tv). Basically, both
screens seem to be perfectly setup, no overscale, no clipping of UI or
playback.

Both seem to exhibit the random video stutter in fast pans during ISO
DVD playback. And typically, its non-reproducible. If I notice it
during a movie, then later go back to that point in the film, it pans
perfectly. It is so slight, my wife doesn't notice it at all.

SD and HD recorded via QAM HDHomeRun never have this problem. They
play perfectly. It so far is limited to DVD ISO playback. Have never
noticed if AVIs exhibit this, since we primarily only watch ISOs.

OpenGL sync is on. Tried it off. The systems both have nVidia cards,
and the driver that minimyth is using is v169.12.

I've seen suggestions to try different deinterlacers. None seem to
matter. Also, I read that if the player detects non-interlaced
content(like a DVD movie), it will turn off the deinterlacing. So that
would seem to indicate that the choice of deinterlacing method
shouldn't matter.

My playback profile was High Quality prior to the testing of various
configurations.

My next step was going to be to try xine, but I would prefer to use
the internal player due to its nice OSD.

In Xorg.log, it shows a possible mode as
(II) NVIDIA(0): "1920x1080_60_0" : 1920 x 1080 @ 59.94/60 Hz (CEA-861B
Format 16)

Should that one be used instead of the "1920x1080" that I'm using?

Thanks for any help. Please let me know if any more information would
be helpful.

Robert



details from main system
2.6.23.17, NVIDIA GPU GeForce 6150, AMD proc, current minimyth from
beginning of August.

nvidia xorg.cong section
    Driver      "nvidia"
    Option      "NoLogo"              "true"
    Option      "ConnectedMonitor"    "DFP"
    Option      "TVStandard"          "NTSC-M"
    Option      "TVOutFormat"         "AUTOSELECT"
    Option      "TVOverScan"          "0.0"
    Option      "UseEdidFreqs"        "false"
    Option      "UseEDIDDpi"          "false"
    Option      "DynamicTwinView"     "false"
    Option      "UseEvents"           "true"
    Option      "ExactModeTimingsDVI" "true"
    Option      "ModeValidation"      "NoDFPNativeResolutionCheck"


Monitor section
    Identifier  "Monitor1"
    DisplaySize 480 270
    HorizSync 10.0-70.0
    VertRefresh 58.0-62.0

screen section
       Depth       24
        Virtual     1920 1080
        ViewPort    0 0
        Modes       "1920x1080"



mythfrontend --version
Please include all output in bug reports.
MythTV Version   : Unknown
MythTV Branch    : branches/release-0-21-fixes
Library API      : 0.21.20080304-1
Network Protocol : 40
Options compiled in:
 linux release using_oss using_alsa using_backend using_dvb
using_frontend using_joystick_menu using_lirc using_opengl_vsync
using_opengl_video using_x11 using_xrandr using_xv using_xvmc
using_xvmc_vld using_opengl using_ffmpeg_threads