Hi Gerd, Thanks for the fast reply! So a half-frame is actually taken 20ms before the time of its timestamp? (with a PAL camera, 50 half-frames a second) Or does it take less than 20ms (PAL) to transmit the half-frame from the camera to the frame-grabber? Thanks again: Thilo Gerd Knorr wrote: > > Thilo Weigel wrote: > > Hi all, > > > > I'm currently writing an application where I need to know as exactly as > > possible the time a half-frame was taken by the camera. I'm wondering > > which value exactly the timestamp field in the v4l2_buffer struct holds. > > Is it the system time when transmission of the half-frame started, the > > time when the half-frame has just arrived completely in computer memory > > or is there even a further delay? > > Completely arrived, the irq handler handling the "capture done" takes > the timestamp (bttv 0.8.x + saa7134). > > Gerd > > -- > You can't please everybody. And usually if you _try_ to please > everybody, the end result is one big mess. > -- Linus Torvalds, 2002-04-20 > > _______________________________________________ > Video4linux-list mailing list > Video4linux-list@xxxxxxxxxx > https://listman.redhat.com/mailman/listinfo/video4linux-list -- -------------------------------------------------------------------- Thilo Weigel Albert-Ludwigs-Universitaet Freiburg, Institut fuer Informatik Lehrstuhl fuer Grundlagen der Kuenstlichen Intelligenz Georges-Koehler-Allee, Geb. 52 D-79110 Freiburg, Germany Voice: +49 761 203-8229 Fax: +49 761 203-8222 weigel@xxxxxxxxxxxxxxxxxxxxxxxxxx http://www.informatik.uni-freiburg.de/~weigel --------------------------------------------------------------------
