Justin Schoeman wrote: > > "Gleicon S. Moraes" wrote: > > > > Edgard Alexander Sotter wrote: > > > > [snip] > > > > > someone told me that I have to work with video_buffer struct, > > > anyone has experience in work with this struct???... anyone has a example of > > > grabbing image in real time (video)??? using more than one buffer. > > > > > > > I uploaded an attempt to use the double buffers to grab. > > My primary source of information were the Programming txt found in xawtv > > tarball. > > The link is the same: > > > > http://planeta.terra.com.br/informatica/gleicon/videodog.html > > > > The process looks is: sync buffer one, grab buffer 2, sync buffer 2, > > grab buffer 1. > > I hope it helps, sorry but I did it in a hurry, its not the nicest code > > overthere ... BTW if somebody got some clue to help improve this double > > buffer grab code, I would thank a lot. Probably I will do a presentation > > about video processing using linux, and would be very cool if I got some > > almost-real time processing :-D > > > > Regards. > > Here is a non-bttv specific example. I no longer use v4l, so I can't ... > > Also, please note that to be formally correct, the app must first test > for streaming capabilities with VIDIOCGCAP, and set the picture format > with VIDIOCSPICT (before any call to VIDIOCGMBUF is made). Sorry - there should also be a VIDIOCSWIN ioctl (I think) to set the image size. Quoting the v4l API document: "To use the mmap interface a user first sets the desired image size and depth properties. Next the VIDIOCGMBUF ioctl is issued." The only way I know of to set the size and depth parameters is the SWIN call??? -justin
