Re: [transcode-users] Recording from v4l2?

[Erik Slagter <erik@xxxxxxxxxxxxx>]

On Wed, 2004-12-22 at 12:47 -0500, Adam K Kirchhoff wrote:
> I do have some experience with C, though it's been a number of years 
> since I took those classes in college.  I actually have a little bit of 
> free time coming up, so I'll take a stab at it and see what I can come 
> up with.

Something like this (not tested):

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/time.h>
#include <linux/types.h>
#include <linux/videodev2.h>

int main(char ** argv, int argc)
{
        struct v4l2_fmtdesc fmt;
        int fd, ix;

        
        if((fd = open("/dev/video0", O_RDWR, 0)) < 0)
        {
                fprintf(stderr, "cannot open video device\n");
                close(fd);
                exit(1);
        }

        for(ix = 0; ix < 100; ix++)
        {
                memset(&fmt, 0, sizeof(fmt));
                fmt.index = ix;
                fmt.type = V4L2_BUF_TYPE_CAPTURE;

                if(ioctl(fd, VIDIOC_ENUM_FMT, &fmt))
                {
                        perror("VIDIOC_ENUM_FMT");
                        close(fd);
                        exit(2);
                }

                printf("%x %c%c%c%c %s\n", fmt.pixelformat, (fmt.pixelformat >> 
24) &
255, (fmt.pixelformat >> 16) & 255, (fmt.pixelformat >> 8) & 255,
fmt.pixelformat & 255, fmt.description);
        }

        close(fd);

        return(0);
}