Smooth playback of 1080p

[damur]

While playing a 1080p mkv, I noticed that it was not really smooth. But it was not a performance problem. The problem is called jitter. A cinema movie has a framerate of 23.976 fps, TV Shows 25fps in PAL and 30fps in NTSC. I didn't know which refresh rate xbmc/ubuntu is using. But some frames where shown twice and some not. The playback wasn't smooth.
After some research I tried to edit the "/etc/X11/xorg.conf". I changed HorizSync, VertRefresh both to "120.0". Now the playback is much smoother, but I don't think my TV (a Sony Bravia) does support 120Hz. Has anyone an idea how to see what refresh rate the nvidia drivers are really using? maybe in ubuntu or maybe in TV menu of sony bravia (KDL-46W2000). I think it could still be better.

[phreaks]

I've noticed the same... 1080p movies are not realy smooth... I've got a Sony EX-1.
Any ideas how to fix that?

@Damnur: how have u managed to get 1080p on your TV? My Ubuntu-installation only gives my 1080 interlaced.

[omnium]

Hi,
will you please so kind, and try your content with 'jitter' eg with MPC-HC on W7 (if you have)...



..' jitter = 9 ms', but I can't notice anything on my 24" Dell Monitor with 60HZ. Also no issues with 25/30/?? HZ content.
Do I need a very big screen to notice 'jitter'?

cu,
omnium

<edit> I only found one video with some low 'jitter' at the beginning...but only 'jittering' with WMP not with MPC-HC..

Code: Select all

Video
ID                               : 1
Format                           : AVC
Format/Info                      : Advanced Video Codec
Format-Profil                    : High@L4.1
Format-Einstellungen für CABAC   : Ja
Format-Einstellungen für ReFrame : 7 frames
Muxing-Modus                     : Container profile=Unknown@4.1
Codec-ID                         : V_MPEG4/ISO/AVC
Dauer                            : 1h 36min
Bitrate                          : 5 221 Kbps
nominale Bitrate                 : 5 682 Kbps
Breite                           : 1 280 Pixel
Höhe                             : 720 Pixel
Bildseitenverhältnis             : 16/9
Bildwiederholungsrate            : 25,000 FPS
Auflösung                        : 24 bits
Colorimetrie                     : 4:2:0
Scantyp                          : progressiv
Bits/(Pixel*Frame)               : 0.227
Stream-Größe                     : 3,52 GiB (80%)
verwendete Encoder-Bibliothek    : x264 core 67 r1145M d2e1e1c
Kodierungseinstellungen          : cabac=1 / ref=7 / deblock=1:0:0 / analyse=0x3:0x113 / me=umh / subme=7 / psy_rd=0.8:0.0 / mixed_ref=1 / me_range=24 / chroma_me=1 / trellis=2 / 8x8dct=1 / cqm=0 / deadzone=21,11 / chroma_qp_offset=-2 / threads=3 / nr=0 / decimate=1 / mbaff=0 / bframes=3 / b_pyramid=1 / b_adapt=2 / b_bias=0 / direct=3 / wpredb=0 / keyint=250 / keyint_min=25 / scenecut=40 / rc=2pass / bitrate=5682 / ratetol=1.0 / qcomp=0.60 / qpmin=10 / qpmax=51 / qpstep=4 / cplxblur=20.0 / qblur=0.5 / vbv_maxrate=40000 / vbv_bufsize=40000 / ip_ratio=1.40 / pb_ratio=1.30 / aq=1:0.70

_all_ other Videos I tried, play without 'jittering'....even no problems with such well known/dreaded and bashed(from NMT users) profiles 'High@L5.1/15 frames'...regardless which player I use (WMP/MPC-HC).

</edit>

[damur]

@Damnur: how have u managed to get 1080p on your TV? My Ubuntu-installation only gives my 1080 interlaced.

I don't know, it was set to progressive by default.

[gimp999]

Hi Guys,

I had this jitter problem, as well. My TV is a 42" Panasonic, connected by HDMI and I found I always got jitters in my playback with any 1080p video, it was only small on some films, but the higher the bit rate the worse it became.

Finally I edited my /etc/X11/xorg.conf file, with a few different ideas from other XBMC users and now it's running perfectly I don't see any of the jitters any more.

Anyway here are the changes I made to the default xorg.conf file
In the Monitor Section:
HorizSync 31.0 - 69.0
VertRefresh 59.0 - 86.0

In the Device Section:
Option "DynamicTwinView" "False"
Option "TripleBuffer" "True"

In the Screen Section:
Option "TwinView" "False"
Option "AddARGBGLXVisuals" "True"

And finally I added an Extensions Section:
Section "Extensions"
Option "Composite" "Disable"
EndSection

Hope this helps, fixed all of my problems.

[damur]

i finally got rid jitter, too. I added this line to the "Screen" section:

Code: Select all

Option "UseEDIDFreqs" "False"

Now the nvVidia drivers really use the rate I specified in xorg.conf

[Foxter]

gimp999 you are the BEST!!!!

I edited the same way the xorg.conf file and now my HD content runs flawlessly and smoother than ever!!! No jitter at all!!!

I have a Sony Bravia 40" LCD TV and I'm running xbmc on Ubuntu...

Now the revo has become the absolute media center with the xbmc running perfectly!

YESSSSS!!!!!!!!!

[Stratos]

Hi all,

I got my Revo a few weeks ago and I'm loving it. I've installed Ubuntu 9.10 & XBMC 9.11alpha1 and solved my video clipping using gimp999 setup (thanks gimp999). Until recently I'd only played low res flv's I'd downloaded from youtube. Last night I installed the BBC iPlayer to try some HD.... it was terrible! The screen refresh rate is about 1Hz! Is there anything obvious I'm doing wrong? The audio is OK, I've got the latest Nvidia driver (190) and both audio and video outputs are via HDMI.

On a different subject, I've set up my Wiimote. It works great in gnome but when I launch XBMC the pointer sensitivity is far to high. I expect I could adjust the sensitivity to make it work in XBMC but I guess it would then make it to slow for gnome.......

Any tips gratefully received.

Cheers,

Andy.