Mailing List Archive: MythTV: Users

Jerky panning all cards and resolutions. Thoughts on where to look?

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william_munson at bellsouth

May 14, 2007, 1:32 PM

Post #1 of 16 (4523 views)
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Jerky panning all cards and resolutions. Thoughts on where to look?

Hi Listland,

Since day one I have noticed that panning scenes have a distinct
"gallop". This is independent of video mode, resolution, signal source,
real time setting or rendering method. On about a 1/2 to 1 second cycle
the pan will speed up and slow down in a repeating pattern. Nothing I
have tried has fixed the problem. I dont think this is related to cpu
usage as it happens even when playing SD which results in an average
usage of about 12%. HD playback is 50-55% usage. The box is a dedicated
myth system with a 2.8GHz AthlonXP mobile with plenty of memory. Signal
sources are 2 pvr-250's and a HDHR. Video card is a NVidia FX5200 using
the standard VGA output to drive my HD monitor. This has happened since
myth 0.19 and is present in 0.20, 0.20.1 and SVN so I doubt its myth
itself. Any suggestions on what else to check?

Bill

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lists at benlancaster

May 15, 2007, 1:27 AM

Post #2 of 16 (4426 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

>
> Since day one I have noticed that panning scenes have a distinct
> "gallop". This is independent of video mode, resolution, signal source,
> real time setting or rendering method. On about a 1/2 to 1 second cycle
> the pan will speed up and slow down in a repeating pattern. Nothing I
> have tried has fixed the problem. I dont think this is related to cpu
> usage as it happens even when playing SD which results in an average
> usage of about 12%. HD playback is 50-55% usage. The box is a dedicated
> myth system with a 2.8GHz AthlonXP mobile with plenty of memory. Signal
> sources are 2 pvr-250's and a HDHR. Video card is a NVidia FX5200 using
> the standard VGA output to drive my HD monitor. This has happened since
> myth 0.19 and is present in 0.20, 0.20.1 and SVN so I doubt its myth
> itself. Any suggestions on what else to check?
Are you by any chance watching 50Hz/25Hz source over 60Hz VGA? If you're
in the UK/Australia then this is probably the case - the problem is
caused by mythtv's framerate interpolation (adding the extra 10 frames
to make it up to 60) as it would seem it just duplicates frames, hence
the jerkiness

The only solution is to go for DVI->HDMI and set it to 50Hz. I tried
component on my Nvidia 6200 card, but from what I read Nvidia have
"locked" the component output to 60Hz, so you get the same problem.

Very annoying, I know. This is one thing that MCE has over MythTV - 50Hz
video plays flawlessly smooth over a 60Hz link!

Ben
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william_munson at bellsouth

May 15, 2007, 3:11 AM

Post #3 of 16 (4419 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

Ben Lancaster wrote:
>> Since day one I have noticed that panning scenes have a distinct
>> "gallop". This is independent of video mode, resolution, signal source,
>> real time setting or rendering method. On about a 1/2 to 1 second cycle
>> the pan will speed up and slow down in a repeating pattern. Nothing I
>> have tried has fixed the problem. I dont think this is related to cpu
>> usage as it happens even when playing SD which results in an average
>> usage of about 12%. HD playback is 50-55% usage. The box is a dedicated
>> myth system with a 2.8GHz AthlonXP mobile with plenty of memory. Signal
>> sources are 2 pvr-250's and a HDHR. Video card is a NVidia FX5200 using
>> the standard VGA output to drive my HD monitor. This has happened since
>> myth 0.19 and is present in 0.20, 0.20.1 and SVN so I doubt its myth
>> itself. Any suggestions on what else to check?
>>
> Are you by any chance watching 50Hz/25Hz source over 60Hz VGA? If you're
> in the UK/Australia then this is probably the case - the problem is
> caused by mythtv's framerate interpolation (adding the extra 10 frames
> to make it up to 60) as it would seem it just duplicates frames, hence
> the jerkiness
>
> The only solution is to go for DVI->HDMI and set it to 50Hz. I tried
> component on my Nvidia 6200 card, but from what I read Nvidia have
> "locked" the component output to 60Hz, so you get the same problem.
>
> Very annoying, I know. This is one thing that MCE has over MythTV - 50Hz
> video plays flawlessly smooth over a 60Hz link!
>
> Ben
>

Thanks Ben. Unfortunately its not the issue. I am in the usa and my
modeline is 59.95 hz. The tv is very picky about its signal and that is
the only value that will work. Any other ideas?

Bill

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wimfokkens at planet

May 15, 2007, 11:27 AM

Post #4 of 16 (4415 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

> Very annoying, I know. This is one thing that MCE has over MythTV - 50Hz
> video plays flawlessly smooth over a 60Hz link!
>
> Ben

How did you make that happen. (what codec where you using etc.)

Wim

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wimfokkens at planet

May 15, 2007, 11:28 AM

Post #5 of 16 (4416 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

> Thanks Ben. Unfortunately its not the issue. I am in the usa and my
> modeline is 59.95 hz. The tv is very picky about its signal and that is
> the only value that will work. Any other ideas?
>
> Bill

What deinterlacer are you using (if at all) the only one running smouth on
my system is BOB.

Wim

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danielk at cuymedia

May 15, 2007, 11:59 AM

Post #6 of 16 (4416 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

On Mon, 2007-05-14 at 16:32 -0400, William Munson wrote:
> Hi Listland,
>
> Since day one I have noticed that panning scenes have a distinct
> "gallop". This is independent of video mode, resolution, signal source,
> real time setting or rendering method. On about a 1/2 to 1 second cycle
> the pan will speed up and slow down in a repeating pattern. Nothing I
> have tried has fixed the problem. I dont think this is related to cpu
> usage as it happens even when playing SD which results in an average
> usage of about 12%. HD playback is 50-55% usage. The box is a dedicated
> myth system with a 2.8GHz AthlonXP mobile with plenty of memory. Signal
> sources are 2 pvr-250's and a HDHR. Video card is a NVidia FX5200 using
> the standard VGA output to drive my HD monitor. This has happened since
> myth 0.19 and is present in 0.20, 0.20.1 and SVN so I doubt its myth
> itself. Any suggestions on what else to check?

It is probably your V-Sync method. Try OpenGL V-Sync and make sure you
disable "Sync To VBlank" in nvidia-settings for both
the "Video Texture Adaptor" and the "Video Blitter Adaptor"
under "X Server XVideo Settings". If that doesn't work try the
other V-Sync methods, but make sure the "Sync To VBlank"
settings are enabled.

-- Daniel

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lists at benlancaster

May 17, 2007, 2:23 PM

Post #7 of 16 (4388 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

On 15 May 2007, at 19:27, Wim Fokkens wrote:

>> Very annoying, I know. This is one thing that MCE has over MythTV
>> - 50Hz
>> video plays flawlessly smooth over a 60Hz link!
>>
>> Ben
>
> How did you make that happen. (what codec where you using etc.)

I didn't do anything per-se. I have a friend with near-identical
hardware (same graphics card/capture card chipset and identical TV)
but he uses MCE and I'm on MythTV. Panning/and titles (horizontal or
vertical) are noticeably smoother on his machine. I believe he's
using the out-of-the-box settings for video playback on MCE.

Ben
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endaf at zener

May 17, 2007, 2:45 PM

Post #8 of 16 (4392 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

william_munson at bellsouth

May 17, 2007, 4:33 PM

Post #9 of 16 (4386 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

Endaf Jones wrote:
> On Mon, 2007-05-14 at 16:32 -0400, William Munson wrote:
>
>> Hi Listland,
>>
>> Since day one I have noticed that panning scenes have a distinct
>> "gallop". This is independent of video mode, resolution, signal source,
>> real time setting or rendering method. On about a 1/2 to 1 second cycle
>> the pan will speed up and slow down in a repeating pattern. Nothing I
>> have tried has fixed the problem.
>>
>
> You may want to try changing the Kernel's "HZ" setting to 300 Hz.
> This provides good even timing for both 50 and 60 Hz display systems.
>
> This was brought up in the mail list in the past few months.
>

Not sure I know enough about kernel settings to feel comfortable that I
am not going to screw things up worse. Is there a good guide or has
someone got a precompiled kernel for Ubuntu Edgy with the needed
"fixes"? I know enough to recompile nvidia and the other manually
installed packages, just not the kernel. I would really hate to end up
with a non-bootable system. :(

TIA,
Bill

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ahornby at darlug

May 18, 2007, 2:45 AM

Post #10 of 16 (4392 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

If you are using an NVIDIA card try this in /etc/X11/xorg.conf

Section "Extensions"
Option "Composite" "Disable"
EndSection

I did this and noticed an immediate improvement.
NViIDIA 7600 AGP card, Athlon 3200+, 1GB DDR500 RAM, fedora core 6 and atrpms myth packages, NVIDIA 9755 driver, kernel deinterlacing and ffmpeg (standard) mpeg decoding.
I have all the OpenGL sync options enabled and run 1080i resolution over DVI at 50Hz

Hope this helps.

Regards Anthony.

----- Original Message -----
From: "William Munson" <william_munson [at] bellsouth>
To: "Discussion about mythtv" <mythtv-users [at] mythtv>
Sent: Friday, May 18, 2007 9:03:55 AM (GMT+0930) Australia/Darwin
Subject: Re: [mythtv-users] Jerky panning all cards and resolutions. Thoughts on where to look?

Endaf Jones wrote:
> On Mon, 2007-05-14 at 16:32 -0400, William Munson wrote:
>
>> Hi Listland,
>>
>> Since day one I have noticed that panning scenes have a distinct
>> "gallop". This is independent of video mode, resolution, signal source,
>> real time setting or rendering method. On about a 1/2 to 1 second cycle
>> the pan will speed up and slow down in a repeating pattern. Nothing I
>> have tried has fixed the problem.
>>
>
> You may want to try changing the Kernel's "HZ" setting to 300 Hz.
> This provides good even timing for both 50 and 60 Hz display systems.
>
> This was brought up in the mail list in the past few months.
>

Not sure I know enough about kernel settings to feel comfortable that I
am not going to screw things up worse. Is there a good guide or has
someone got a precompiled kernel for Ubuntu Edgy with the needed
"fixes"? I know enough to recompile nvidia and the other manually
installed packages, just not the kernel. I would really hate to end up
with a non-bootable system. :(

TIA,
Bill

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--
Mr Anthony Hornby
Associate Director, Resources and Technology
Library and Information Access
Charles Darwin University (CRICOS 300K)
Phone: +61 8 8946 6011
Email: anthony.hornby [at] cdu(remove the .no-spam)

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lan at falleagle

May 18, 2007, 10:49 AM

Post #11 of 16 (4380 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

Would these settings also apply to an old GeForce 4000?

On Fri, May 18, 2007 2:45 am, Anthony Hornby wrote:
> If you are using an NVIDIA card try this in /etc/X11/xorg.conf
>
> Section "Extensions"
> Option "Composite" "Disable"
> EndSection
>
> I did this and noticed an immediate improvement.
> NViIDIA 7600 AGP card, Athlon 3200+, 1GB DDR500 RAM, fedora core 6 and
> atrpms myth packages, NVIDIA 9755 driver, kernel deinterlacing and ffmpeg
> (standard) mpeg decoding.
> I have all the OpenGL sync options enabled and run 1080i resolution over
> DVI at 50Hz
>
> Hope this helps.
>
> Regards Anthony.
>
> ----- Original Message -----
> From: "William Munson" <william_munson [at] bellsouth>
> To: "Discussion about mythtv" <mythtv-users [at] mythtv>
> Sent: Friday, May 18, 2007 9:03:55 AM (GMT+0930) Australia/Darwin
> Subject: Re: [mythtv-users] Jerky panning all cards and
> resolutions. Thoughts on where to look?
>
> Endaf Jones wrote:
>> On Mon, 2007-05-14 at 16:32 -0400, William Munson wrote:
>>
>>> Hi Listland,
>>>
>>> Since day one I have noticed that panning scenes have a distinct
>>> "gallop". This is independent of video mode, resolution, signal source,
>>> real time setting or rendering method. On about a 1/2 to 1 second cycle
>>> the pan will speed up and slow down in a repeating pattern. Nothing I
>>> have tried has fixed the problem.
>>>
>>
>> You may want to try changing the Kernel's "HZ" setting to 300 Hz.
>> This provides good even timing for both 50 and 60 Hz display systems.
>>
>> This was brought up in the mail list in the past few months.
>>
>
> Not sure I know enough about kernel settings to feel comfortable that I
> am not going to screw things up worse. Is there a good guide or has
> someone got a precompiled kernel for Ubuntu Edgy with the needed
> "fixes"? I know enough to recompile nvidia and the other manually
> installed packages, just not the kernel. I would really hate to end up
> with a non-bootable system. :(
>
> TIA,
> Bill
>
>
> _______________________________________________
> mythtv-users mailing list
> mythtv-users [at] mythtv
> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>
>
> --
> Mr Anthony Hornby
> Associate Director, Resources and Technology
> Library and Information Access
> Charles Darwin University (CRICOS 300K)
> Phone: +61 8 8946 6011
> Email: anthony.hornby [at] cdu(remove the .no-spam)
>
> _______________________________________________
> mythtv-users mailing list
> mythtv-users [at] mythtv
> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
>

--
Lan Barnes

SCM Analyst Linux Guy
Tcl/Tk Enthusiast Biodiesel Brewer

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reidjr at btconnect

May 19, 2007, 5:26 AM

Post #12 of 16 (4360 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

Daniel Kristjansson wrote:
> On Mon, 2007-05-14 at 16:32 -0400, William Munson wrote:
>
>> Hi Listland,
>>
>> Since day one I have noticed that panning scenes have a distinct
>> "gallop". This is independent of video mode, resolution, signal source,
>> real time setting or rendering method. On about a 1/2 to 1 second cycle
>> the pan will speed up and slow down in a repeating pattern. Nothing I
>> have tried has fixed the problem. I dont think this is related to cpu
>> usage as it happens even when playing SD which results in an average
>> usage of about 12%. HD playback is 50-55% usage. The box is a dedicated
>> myth system with a 2.8GHz AthlonXP mobile with plenty of memory. Signal
>> sources are 2 pvr-250's and a HDHR. Video card is a NVidia FX5200 using
>> the standard VGA output to drive my HD monitor. This has happened since
>> myth 0.19 and is present in 0.20, 0.20.1 and SVN so I doubt its myth
>> itself. Any suggestions on what else to check?
>>
>
> It is probably your V-Sync method. Try OpenGL V-Sync and make sure you
> disable "Sync To VBlank" in nvidia-settings for both
> the "Video Texture Adaptor" and the "Video Blitter Adaptor"
> under "X Server XVideo Settings". If that doesn't work try the
> other V-Sync methods, but make sure the "Sync To VBlank"
> settings are enabled.
>
> -- Daniel
>
> _______________________________________________
> mythtv-users mailing list
> mythtv-users [at] mythtv
> http://mythtv.org/cgi-bin/mailman/listinfo/mythtv-users
> "Sync To VBlank"
>
>
Daniel,

Do you mean disable or enable

"Sync To VBlank"

or do you only disable when you dont use OpenGL ??

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lists at panic

May 19, 2007, 5:58 AM

Post #13 of 16 (4359 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

On 19/05/2007 10:26 PM, John wrote:
> Daniel Kristjansson wrote:
>
>> It is probably your V-Sync method. Try OpenGL V-Sync and make sure you
>> disable "Sync To VBlank" in nvidia-settings for both
>> the "Video Texture Adaptor" and the "Video Blitter Adaptor"
>> under "X Server XVideo Settings". If that doesn't work try the
>> other V-Sync methods, but make sure the "Sync To VBlank"
>> settings are enabled.
>>
> Do you mean disable or enable
>
> "Sync To VBlank"
>
> or do you only disable when you dont use OpenGL ??
>
I'm keen to know the answer of this too, one one of my frontends I've
got this problem, I've tried playing with the sync settings in
nvidia-settings, and seemed to have solved this problem with the
"flipping" setting in nvidia-settings. I'm not able to access that
frontend at the moment as my wife is catching up on "heros" so I can't
confirm that actual name of the setting.

Please let us know.

Regards,
--

Patrick Nichols

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william_munson at bellsouth

May 26, 2007, 10:18 AM

Post #14 of 16 (4288 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

Ben Lancaster wrote:
>> Since day one I have noticed that panning scenes have a distinct
>> "gallop". This is independent of video mode, resolution, signal source,
>> real time setting or rendering method. On about a 1/2 to 1 second cycle
>> the pan will speed up and slow down in a repeating pattern. Nothing I
>> have tried has fixed the problem. I dont think this is related to cpu
>> usage as it happens even when playing SD which results in an average
>> usage of about 12%. HD playback is 50-55% usage. The box is a dedicated
>> myth system with a 2.8GHz AthlonXP mobile with plenty of memory. Signal
>> sources are 2 pvr-250's and a HDHR. Video card is a NVidia FX5200 using
>> the standard VGA output to drive my HD monitor. This has happened since
>> myth 0.19 and is present in 0.20, 0.20.1 and SVN so I doubt its myth
>> itself. Any suggestions on what else to check?
>>
> Are you by any chance watching 50Hz/25Hz source over 60Hz VGA? If you're
> in the UK/Australia then this is probably the case - the problem is
> caused by mythtv's framerate interpolation (adding the extra 10 frames
> to make it up to 60) as it would seem it just duplicates frames, hence
> the jerkiness
>
> The only solution is to go for DVI->HDMI and set it to 50Hz. I tried
> component on my Nvidia 6200 card, but from what I read Nvidia have
> "locked" the component output to 60Hz, so you get the same problem.
>
> Very annoying, I know. This is one thing that MCE has over MythTV - 50Hz
> video plays flawlessly smooth over a 60Hz link!
>

Replying to my own message. I finally found out what caused my jerky
video issues. It turned out to be my storage method. I was running a
LVM on a pair of IDE drives and a SATA drive using XFS on top of the
LVM. I removed the LVM and converted back to three XFS formatted
partitions and used the storage directory feature in SVN with two of
the partitions. Now it plays as smooth as butter and almost all of the
video break-up is gone. The breakups that are left appear to be from my
crappy ComCrap cable service. I suspect that all the overhead of both
XFS and LVM where causing enough latency to be a problem. In case you
were wondering, the third partition is now dedicated to my dvd rips and
music.

One more mystery solved.

Bill

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danielk at cuymedia

Jun 13, 2007, 7:01 AM

Post #15 of 16 (4143 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

On Sat, 2007-05-19 at 13:26 +0100, John wrote:
> Daniel Kristjansson wrote:
> > On Mon, 2007-05-14 at 16:32 -0400, William Munson wrote:
> > It is probably your V-Sync method. Try OpenGL V-Sync and make sure you
> > disable "Sync To VBlank" in nvidia-settings for both
> > the "Video Texture Adaptor" and the "Video Blitter Adaptor"
> > under "X Server XVideo Settings". If that doesn't work try the
> > other V-Sync methods, but make sure the "Sync To VBlank"
> > settings are enabled.
> Do you mean disable or enable
> "Sync To VBlank"
Disable for OpenGL V-Sync, enable for the other methods.

FYI RTC is really the one you wan't if you can't use
OpenGL V-Sync for any reason.

> or do you only disable when you dont use OpenGL ??
You disable it whenever you are using a OpenGL V-Sync. Otherwise
MythTV will wait for the retrace using the OpenGL V-Sync, then
send the video frame to the card and the nVidia driver will make
it wait for the next retrace before it shows the frame. When
you are using RTC or another non-retrace based V-Sync method
you want the "Sync to VBlank" to be enabled, at least with the
latest drivers where this isn't a big performance hit. But if
MythTV is already using the retrace to time the showing of
frames then having "Sync to VBlank" enabled makes us wait for
two retraces for each frame, with older drivers this means we
show half as many frames as we could, leading to less than ideal
motion, and with the newer drivers it means the video is always
at least one retrace further behind audio than MythTV thinks it
is in it's A/V Sync calculation, so lip sync is less than ideal.

-- Daniel

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ignasiak at gmail

Jun 13, 2007, 9:06 AM

Post #16 of 16 (4136 views)
Permalink

Re: Jerky panning all cards and resolutions. Thoughts on where to look? [In reply to]

On 5/26/07, William Munson <william_munson [at] bellsouth> wrote:
> Ben Lancaster wrote:
> >> Since day one I have noticed that panning scenes have a distinct
> >> "gallop". This is independent of video mode, resolution, signal source,
> >> real time setting or rendering method. On about a 1/2 to 1 second cycle
> >> the pan will speed up and slow down in a repeating pattern. Nothing I
> >> have tried has fixed the problem. I dont think this is related to cpu
> >> usage as it happens even when playing SD which results in an average
> >> usage of about 12%. HD playback is 50-55% usage. The box is a dedicated
> >> myth system with a 2.8GHz AthlonXP mobile with plenty of memory. Signal
> >> sources are 2 pvr-250's and a HDHR. Video card is a NVidia FX5200 using
> >> the standard VGA output to drive my HD monitor. This has happened since
> >> myth 0.19 and is present in 0.20, 0.20.1 and SVN so I doubt its myth
> >> itself. Any suggestions on what else to check?
> >>
> > Are you by any chance watching 50Hz/25Hz source over 60Hz VGA? If you're
> > in the UK/Australia then this is probably the case - the problem is
> > caused by mythtv's framerate interpolation (adding the extra 10 frames
> > to make it up to 60) as it would seem it just duplicates frames, hence
> > the jerkiness
> >
> > The only solution is to go for DVI->HDMI and set it to 50Hz. I tried
> > component on my Nvidia 6200 card, but from what I read Nvidia have
> > "locked" the component output to 60Hz, so you get the same problem.
> >
> > Very annoying, I know. This is one thing that MCE has over MythTV - 50Hz
> > video plays flawlessly smooth over a 60Hz link!
> >
>
> Replying to my own message. I finally found out what caused my jerky
> video issues. It turned out to be my storage method. I was running a
> LVM on a pair of IDE drives and a SATA drive using XFS on top of the
> LVM. I removed the LVM and converted back to three XFS formatted
> partitions and used the storage directory feature in SVN with two of
> the partitions. Now it plays as smooth as butter and almost all of the
> video break-up is gone. The breakups that are left appear to be from my
> crappy ComCrap cable service. I suspect that all the overhead of both
> XFS and LVM where causing enough latency to be a problem. In case you
> were wondering, the third partition is now dedicated to my dvd rips and
> music.

I had a similar issue not too long ago. I was tweaking the hell out
of my frontend, blaming it for the playback problems and only realized
it was the backend after some streaming issues with another app.
I'm still not sure exactly why the backend was performing poorly.. it
had plenty of CPU, decent disks, and everything looked fine on it.
But, after re-installing that system it worked fine. The old
install was running Ubuntu (6.04, I think) and using LVM. My new
install is Ubuntu Feisty, non-LVM, with jfs filesystems for myth
storage.

Is this common with LVM? Or maybe an older version of LVM like I was using?

Any recommendations for others to diagnose this? It wasn't clear at
all where the problem was.. If I remember correctly, and I may not
be, the hdparm performance numbers for the LVM filesystem were fine.
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