Problems using V4L2 and bttv 0.9.4

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Hello,
	We would like to use the V4L2 API described at
	http://bytesex.org/v4l/spec/  and, as described
	in the documentation, we applied the patch patch-2.4.20-kraxel 
	to the kernel 2.4.20.
Then we installed bttv 0.9.4 and we verified that it works with xawtv.

Everything seems to work fine till here, even if we don't undestand if
the API used by xawtv is the v4l or v4l2. No problems also with
bttvgrab.

The next step we tried to do was to write our first test program, in
order to try to get infromation from the card. We used the snippet code
found in the documentation at http://bytesex.org/v4l/spec/x306.html#AEN366

The snippet code below does not work.

standard.index = 0;
while (0 == ioctl (fd, VIDIOC_ENUMSTD, &standard)) {
   if (standard.id & std) {
       printf ("Current video standard: %s\n", standard.name);
       exit (EXIT_SUCCESS);
   }
   standard.index++;

We saw in the kernel code that standard.index is resetted every time the
ioctl is called, as you can see below:

v4l2-common.c :
int v4l2_video_std_construct(struct v4l2_standard *vs, int id, char *name)
				 {
				     memset(vs, 0, sizeof(struct v4l2_standard));
					 ...


What's the problem?
Is the API documentation too old or is the implementation not yet
conforming the standard?

We have problems also with query capabilities: the strings
returned by VIDIOC_QUERYCAP have no sense.

Is there any place where we could find some good short running examples
that follows the cited documentation to test our installation?

Thanks in advance.
--
Fabrizio Cornelli - Sandro Bosio

University of Milan - Italy





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