Hello Justin, Wednesday, July 11, 2001, 12:13:21 AM, you wrote: JS> "M. Osten" wrote: >> >> I use vcr to capture television programs with a brooktree tuner/capture >> card. It seems that the channels at the lower end of the spectrum (ie >> 2,3,4) have poor reception due to bad in wall cables. When I do >> captures on these channels drop lots of frames in an hour. Channels at >> the higher end of the spectrum do fine. >> >> Machine is a dual P3 933 with 1 gig of ram, and 170 gig of ATA 100 >> 7200rpm drives. >> >> Capture thread exiting >> Captured 111504 frames. >> Frames dropped in capture: 652 (0.0%) >> Frames dropped in encoder: 1191 (0.0%) >> Exiting.. >> Waiting for write thread >> MP3EncodeR::Close() >> Write thread exiting >> Waiting for audio thread >> Waiting for video thread >> All threads exited >> v4l1: VIDIOCCAPTURE in ::setCapture >> v4l1: VIDIOCSYNC in ::~v4l1if >> v4l1: ioctl VIDIOCCAPTURE in v4l1if::~v4l1if >> Total Unfree 3596428 bytes cnt 49 [0,0] JS> If the signal is weak, the video capture card will often miss the JS> vertical synchronisation pulse (it gets lost in the background noise). JS> When this happens, it detects that too many lines have been received in JS> a frame, and does a resynchronisation, effectively dropping a frame. JS> The only way around this is to get a better signal. If I understand the problem correctly, there is a workaround. I had similar problem when capturing from bad-quality VCR tapes. Frame drop was much worse than in this case ( 652 out of 110k frames dropped is nothing; I was experiencing up to 30-50% drop ). At last I wrote a small patch for bttv (http://null.ru/people/hamster/bttv-drop.diff.gz) that completely fixed the problem. It was taken against 0.7.39, shouldn't be hard to port to newer version. -- Best regards, Eugene mailto:divx@xxxxxxx or sparky@xxxxxxxxxxxxxxx [Team GADGET] [Team Two Divided By Zero]
