2009-06-07, 19:21
Hi!
New in this forum and ready to do all things wrong on my first post but here you go
I built a small HTPC with the Zotac ION A (Atom 330) with 4 GB of RAM last week. It works pretty well, however struggles on 720p content.
My TV (Sony KDL X4500) runs in 1080p resolution and when viewing 1080p MKVs it runs perfectly smooth (using VDPAU), however on some 720p MKVs I have huge problems with jerky playback, it's just not smooth.
Now I figured that when I switch the video output during playback to the original 1280x720 (with huge black bars around the picture of course) it runs smoothly.
So I guess the problem comes from the upscaling of the image from 1280x720 to 1920x1080 - I guess VDPAU isn't used for that!?
I tried all options in settings, upscaling deactivated (still does upscale tho..) and bicubic, lanczos and the 3rd one, also this "use SD content" stuff. it's actually always the same. if i use "orginal" picture in video (with huge black bars around) it's smooth, if i go to the "normal" picture mode using full screen then it's jerky again.
also it seems to differ from MKV to MKV, movies and US TV show MKVs seem to work almost flawlessly, on 25/50 Hz PAL material it's very bad tho (for example I have some recording from Eurovision song contest converted to an 25 FPS MKV which runs jerky, same with an ORF HD recording that I play directly - for the latter one there is also a prob with the framerate as it doesn't even display 25 or 50 but smthg around 40 FPS, but I guess this is a different problem).
now question is what to do about it?
is it possible that in the future VDPAU is used for the upscaling?
or is there a way to make XBMC switch to an actual 720p output resolution for playback of 720p content (I tried this but it didn't seem to work, added some 720p modelines to xorg.conf but XBMC kept playing using 1920x1080 res, also tried the "upscaling deactivated" setting for that - no go). also I didn't find any modeline for [email protected] and/or 24p if that is even possible.
anyone else also experienced this problem with an ION based HTPC and maybe knows a way around it?
XBMC version is pre-9.10 r20830M btw
Nvidia driver is latest one (185....something)
also had it running with an XBMC version a few weeks older and an NVidia 180.... driver before and it was the same.
update: also checked CPU usage now and tried with and without hyperthreading (makes no difference):
XBMC seems to fully utilize one of the cores always even when not playing a video and just looking at the settings-hardware window. one of the CPUs is always at 100%, also the load switches between the CPUs from time to time - is that normal?
New in this forum and ready to do all things wrong on my first post but here you go
I built a small HTPC with the Zotac ION A (Atom 330) with 4 GB of RAM last week. It works pretty well, however struggles on 720p content.
My TV (Sony KDL X4500) runs in 1080p resolution and when viewing 1080p MKVs it runs perfectly smooth (using VDPAU), however on some 720p MKVs I have huge problems with jerky playback, it's just not smooth.
Now I figured that when I switch the video output during playback to the original 1280x720 (with huge black bars around the picture of course) it runs smoothly.
So I guess the problem comes from the upscaling of the image from 1280x720 to 1920x1080 - I guess VDPAU isn't used for that!?
I tried all options in settings, upscaling deactivated (still does upscale tho..) and bicubic, lanczos and the 3rd one, also this "use SD content" stuff. it's actually always the same. if i use "orginal" picture in video (with huge black bars around) it's smooth, if i go to the "normal" picture mode using full screen then it's jerky again.
also it seems to differ from MKV to MKV, movies and US TV show MKVs seem to work almost flawlessly, on 25/50 Hz PAL material it's very bad tho (for example I have some recording from Eurovision song contest converted to an 25 FPS MKV which runs jerky, same with an ORF HD recording that I play directly - for the latter one there is also a prob with the framerate as it doesn't even display 25 or 50 but smthg around 40 FPS, but I guess this is a different problem).
now question is what to do about it?
is it possible that in the future VDPAU is used for the upscaling?
or is there a way to make XBMC switch to an actual 720p output resolution for playback of 720p content (I tried this but it didn't seem to work, added some 720p modelines to xorg.conf but XBMC kept playing using 1920x1080 res, also tried the "upscaling deactivated" setting for that - no go). also I didn't find any modeline for [email protected] and/or 24p if that is even possible.
anyone else also experienced this problem with an ION based HTPC and maybe knows a way around it?
XBMC version is pre-9.10 r20830M btw
Nvidia driver is latest one (185....something)
also had it running with an XBMC version a few weeks older and an NVidia 180.... driver before and it was the same.
update: also checked CPU usage now and tried with and without hyperthreading (makes no difference):
XBMC seems to fully utilize one of the cores always even when not playing a video and just looking at the settings-hardware window. one of the CPUs is always at 100%, also the load switches between the CPUs from time to time - is that normal?