I'm sorry for replying to my own post, but I wanted to mention, I see the jerkiness in xine as well. I tested this with a short recording that I also used to compare decoder vs. yuv/xv. (Ripped DVDs also exhibit this in xine.) So this seems to indicate to me it's not a problem with Myth but with the yuv stuff in ivtv. Of course, I can't test xine+PVR350 decoder, so...
--- [EMAIL PROTECTED] wrote: > Over the last couple of weeks, I have noticed there > is > a problem with my yuv playback. In summary, the > playback using the new yuv extensions in ivtv is > jerky, in a subtle but important way. It might be > described as a modulation of the framerate, where > the > modulation itself has frequency components of a few > or > several Hertz. > > Here's the best way I can describe it: > > When there is a scene that has something moving > across > the screen at a rate, say, of between 1 screen width > per second down to 1/6 screen width per second, you > can see that the video is updating in fits and > starts. > It's as if the video spends, say, 1/8 of a second > with a framerate greater than 30/s and then another > 1/8 of a second with a framerate less than 30/s. > It's > as if the feature moving across the screen > alternates > between fast and slow, with the alternation occuring > a > few times a second. In fact, it quite well may be > that the frames stop every now and then for a short > period and then restart with a framerate > 30/s. > > In a lot of cases, you can't tell, such as if you're > just looking at a talking head spit out the day's > news > or something. But certain types of scenes, such as > showing the ground from a moving helicopter or the > Enterprise moving across the screen in Star Trek, > it's > quite obvious, especially now that I know it's > there. > If I look at the text news blurbs at the bottom of > the > screen while tuned to CNN, again, it's obvious. In > fact, it's bad enough that it is starting to get > painful to watch scenes like these on my 36 inch TV. > > If I use the 350's decoder instead, this jerkiness > goes away. Motion is as smooth as silk. It's quite > repeatable, to the point that now I can easily tell > when the decoder is being used, or the yuv/xv stuff > is > being used. > > Now, if there's much motion in the video, I'm even > starting to get noticeably dizzy and it's hurting my > eyes. I don't remember if this has been a problem > all > along, but it's been about two weeks that I've been > seeing it. I had thought it might be solved with > the > vsync issues, but having looked at John Harvey's > latest patch, it fixes the tearing but does *not* > fix > this jerkiness that I'm seeing. It's still there > and > kinda sucks. :( > > So, the obvious questions are: > 1) Is this a bug in ivtv or its yuv extensions? > 2) Is there a setting I can use to fix this? > 3) Is anyone else seeing this? (Look carefully, and > compare some recorded video using yuv and then the > decoder - it's definitely there at least for me.) > 4) Help! > > My system specs: > - Mythtv, version 0.18.1 > - P4 2.4GHz, 1Gig RAM > - ivtv 0.3.7a, patched with John Harvey's latest and > greatest patch > - the ivtvdev_drv.o that came with 0.3.7a > - SuSE Linux 9.2, with kernel 2.6.8-24.16-default > - Xorg 6.8.1 > > I've also attached: > - Relevant portions of /var/log/messages > - Xorg.1.log > - mythfrontend.log > > I hope somebody can help! ------------------------------------------------------- SF.Net email is sponsored by: Discover Easy Linux Migration Strategies from IBM. Find simple to follow Roadmaps, straightforward articles, informative Webcasts and more! Get everything you need to get up to speed, fast. http://ads.osdn.com/?ad_id=7477&alloc_id=16492&op=click _______________________________________________ ivtv-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/ivtv-devel
