////
  unsigned int i;
  enum v4l2_buf_type type;
  for(i = 0; i < 4; i++){
    struct v4l2_buffer buf;
    buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
    buf.memory = V4L2_MEMORY_MMAP;
    buf.index = i;
    ioctl(fd??VIDIOC_QBUF??&buf);
  }
  type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
  ioctl(fd??VIDIOC_STREAMON??&type);
  ////
  struct v4l2_buffer buf;
  buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;
  buf.memory = V4L2_MEMORY_MMAP;
  ioctl(fd??VIDIOC_DQBUF??&buf);
  char path[20];
  snprintf(path??sizeof(path)??"./yuyv%d"??buf.index);
  int fdyuyv = open(path??O_WRONLY|O_CREAT??00700);
  printf("TK--------->>>>fdyuyv is %d "??fdyuyv);
  int resultyuyv = write(fdyuyv??buffers[buf.index].start??1280*720*2);
  printf("TK--------->>>resultyuyv is %d "??resultyuyv);
  close(fdyuyv);
  ////
  close(fd);
  return 0;
}

????????????????

????gcc test.c -o rest

????./test

???????????

???????????????yuyv0??????????????jpeg???????????