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!
messages.gz
Description: 310337513-messages.gz
Xorg.1.log.gz
Description: 1930036253-Xorg.1.log.gz
mythfrontend.log.gz
Description: 2627724585-mythfrontend.log.gz
