Hi Bryan, On Mon, 2002-04-22 at 13:59, Bryan J. Smith wrote: > One interesting issue I am having is with xawtv, both the included 3.54 > in 7.2 as well as Rawhide's 3.73. For some reason, after running for > awhile, I will lose the normal ~640x480 picture and can only "get it > back" if I reduce the xawtv window so it is 128x96! If I try to make it > big again, it looses the picture (sometimes with a little, single scan > line at the very time) I have _no_idea_ why it happens, but a > _cold_reboot_ (complete power-off) seems to be the only way to fix it. This has to do with buffersize images and limitations in the linux kernel to give us bigger contiguous buffers and of the buz card to cope with non-contiguous buffers, as far as I know. It's one of these things I actually don't understand fully, but that might come later on ;-). Don't pin me down on this one ;-). > But even when it happens, I can still use the lavrec and other > MJPEGTools fine to capture. It looks like some kind of "overlay" issue, > although I'm not a regular V4L user (this is my first setup). "-debug > 2" didn't seem to give me anything different than normal. I think it > could be the result of me running another DGA, SDL or other app though. > E.g., I got it once after running MPlayer with SDL output, although I > couldn't reproduce it after rebooting. So it might be random as well. Mjpegtools' lavrec uses JPEG buffers. The card seems to be able to cope with non-contiguous JPEG buffers fairly well (except for some buggy mainboards). This means that A) we need smaller buffers since JPEG video doesn't take as much space as raw video and B) we can use larger buffers than the maximum we can allocate at once contiguously because we can use non-contiguous buffers. As a consequence, JPEG-capture works perfectly and overlay/v4l-capture is pretty limited. > My mainboard is the Tyan Tiger MP (S2460) with the AMD760MP (762+766 > north+south) chipset -- dual-Athlon. My video card is the nVidia > GeForce3 Ti200 with the nVidia closed source drivers. I've tried the > 1.0-2313, 1.0-2802 and 1.0-2880 drivers and don't make a difference > either way. It shouldn't make a difference ;-). Actually, the Tyan Tiger is a kt266A-based mainboard, isn't it? I'm surprised you have this working, you might want to report this on mjpeg-users@xxxxxxxxxxxx, since some people have problems getting it to work on kt266A-based boards. Ronald -- - .-. - /V\ | Ronald Bultje <rbultje@xxxxxxxxxxxxxxxxxxx> - // \\ | Running: Linux 2.4.18-XFS and OpenBSD 3.0 - /( )\ | http://ronald.bitfreak.net/ - ^^-^^
