v4l linux

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>              
#include <unistd.h>
#include <sys/ioctl.h>
#include <linux/videodev2.h>

int main() {
    int fd;
    struct v4l2_format fmt;

    // 打开摄像头设备
    fd = open("/dev/video0", O_RDWR);
    if (fd == -1) {
        perror("Cannot open device");
        return 1;
    }

    // 获取当前格式
    memset(&fmt, 0, sizeof(fmt));
    fmt.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
    fmt.fmt.pix.width = 640;
    fmt.fmt.pix.height = 480;
    fmt.fmt.pix.pixelformat = V4L2_PIX_FMT_YUYV;
    fmt.fmt.pix.field = V4L2_FIELD_INTERLACED;

    if (ioctl(fd, VIDIOC_S_FMT, &fmt) == -1) {
        perror("Setting pixel format failed");
        close(fd);
        return 1;
    }

    printf("Camera opened and formatted successfully
");

    close(fd);
    return 0;
}