the type of the camera is type=V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE
when i capture the picture with the userptr,(buf.memory = V4L2_MEMORY_USERPTR)
,Qbuf was failed.
the process is as follows:
at first i have request the buffer:
buffers=calloc(4,sizeof(*buffers));
for(n_buffers=0;n_buffers<4;++n_buffers){
buffers[n_buffers].length=buffer_size;
buffers[n_buffers].start=malloc(buffer_size);
}
for(i=0;i<n_buffers;++i){
CLEAR(buf);
memset(&planes, 0, sizeof(planes));
buf.m.planes = &planes;
buf.m.planes->length = buffers[i].length;
buf.m.planes->m.userptr = (unsigned long) buffers[i].start;
buf.type=V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE;
buf.memory=V4L2_MEMORY_USERPTR;
buf.index=i;
buf.length=1;
printf("buf.index is %d",buf.index);
int ret=ioctl(fd,VIDIOC_QBUF,&buf);
if(ret<0)
printf("QBUF failed\n");
}
but when I used QBUF to get the frame,the fault was as follows:
VIDIOC_QBUF error 22,Invalid argument.
Please help me !Thanks for your help!
