fast motion video: TV vs GBPVR

[Incongruent]

Okay, so I have a cable splitter on my OTA antenna with one output going to the tv directly and the other going to my HTPC connected to the TV via HDMI port.

I'm watching the Leafs vs Canadians game on live ATSC TV and switching back and forth between the ATSC TV input and the HDMI input. I find a very noticeable difference in smoothness for fast motion action scenes such as the side scrolling down the ice that is done frequently on NHL games.

Firstly, I assume that the quality of components in my $100 Theater 650 PRO tv capture card and my integrated ATI 3200 HD GPU should be lesser than my those components in my TV that are decoding and displaying the ATSC signal.... but should I be expecting a noticeable difference in quality on fast motion?

Secondly, should I expect that i can bring the HTPC closer in-line with the performance on the ATSC tuner of my TV? If so, how do I go about tuning the performance of GBPVR and/or my HTPC to provide similar performance to the TV alone? Which settings should I be looking at tweaking? Is there a FAQ somewhere to help me along?

[pBS]

first off, need some info, what os?, mode?[-vmr9?], decoder?
does medium fast motion look fine?
[both hockey and basketball are the real test of fast motion]

does a freeze frame look better than when in motion?
[should look slightly worse actually, more grainy]

more description of what you're seeing, does it look like mpeg artifacts?[blocks] grain? overlapped frames? trails?

oh and what bitrate are you recording with?
often, fast motion is first to go bad when using too low a bitrate...

[Incongruent]

windows xp 64 bit.
vmr9 fullscreen
How do I freeze frame in GBPVR?
ffdshow decoder, same effect with de-interlacing on and off

The motion seems to be slightly slower than while watching it directly fed into the tv. Also the horizontal scrolling seems to be slightly jerky...only enough to make my eyes gloss over a tad. No artifacts or blocks or anything...

I'm not recording... its during liveplay that I see this.... presumably the live preview is recording I guess right? When I goto Config-->Capture Sources there is no setting for bitrate. Is there another place I can make that adjustment?

[pBS]

ahhh, ffdshow...got latest tryouts version? it's got new stuff in deinterlacing..
but uncheck 'deinterlacing' in ffdshow, let video card do it..

basically for any version of ffdshow, set libmpeg2 as mpeg2 decoder, then go to output options, and tick *only* nv12 as colorspace, and 'set interlace flag in output' and choose either 'auto' or bob if auto isn't available in both 'method' and 'field oder'...and that's it..
attaching pic...
[this is newest beta6 ffdshow tryout version]
latest stable 'tryouts' version should be good also as well as any recent version..
it just won't have all the extra options, but mainly nv12 and set interlaced part are most important,and they have been in there a while....

[pBS]

oh and to change livetv bitrate for analog, it's in direct.ini, the last entry 'EncoderPassthrough', as 'livetv' is timeshift profile..usually it's not a problem tho..
can't change bitrate of hdtv at all..

oh and get 8.11 drivers, stay away from 8.12 as they broke them somewhere..[as usual]
and try the avivo decoder...it offers full accell if all is working right..

[martint123]

can't change bitrate of hdtv at all..

Or any digital broadcast, which I think ATSC is (I'm not over there so don't have it).

I gave up on ATI HD range of cards after much aggro and now stick to nvidea, but that might be just me.

[pBS]

i hear ya....but now that they've got the drivers fixed, they work a charm... [finally!!]
even under xp they accelerate everything...

yea, both sides have had driver issues that can't be overcome no matter what you tweak...
but now it seems they are finally addressing the video playback issues instead of concentrating on just fixing game issues...

[Incongruent]

so I've been using the hd3200 drivers that came with my bios disk... the HD3200 is integrated.

You're recommending I download 8.11 of the catalyst drivers? I presume any version of the avivo drivers are okay and available at the same website.

I've made your recommended changes to the ffdshow codecs and output sections... I'll have to wait for the next game to see how much of a difference this makes.

Thanks for your help! I'll try to reply back when I get some results.

[Incongruent]

ok.. figure skating is on CBC this evening (umm.... yey) so i can do SOME investigation.... the first evident problem with your recommendations was that using libmpeg2 made my stream have very choppy audio, blockyness, corruption... generally it made the program unwatchable. I've tried setting the mpeg2 back to "disabled" in ffdshow and left the other settings as they were.. I'm not sure if it has improved the picture or not yet, but i'll keep watching and report back.


If you're adament that libmpeg2 is the way to go, any ideas on how to troubleshoot the codec?