One way is to measure the time spent for each frame in user space using the demos/utils/TimerUtil benchmarking utility.
 
The budget is 33ms for NTSC or 40 ms for PAL, and because of the missed frame sync a missed frame is normally quite noticeable as it doubles the time spent for a frame (66 ms or 80 ms).
 
Regards,
Niclas


From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Jerry Johns
Sent: Monday, November 06, 2006 2:37 AM
To: [email protected]
Subject: Dropped framecount

Hello all,

             I’ve been tinkering around with the encode H264 demos, and I was wondering if there was a way in V4L2 to find out if any frames were dropped on the input side?

I’ve been looking at using VIDIOC_G_PERF with ioctl, but that’s not supported anymore,

 

So after the

       

       CLEAR(v4l2buf);

        v4l2buf.type = V4L2_BUF_TYPE_VIDEO_CAPTURE;

        v4l2buf.memory = V4L2_MEMORY_MMAP;

 

        /* Get a frame buffer with captured data */

        if (ioctl(inputFd, VIDIOC_DQBUF, &v4l2buf) == -1) {

            if (errno == EAGAIN) {

                continue;

            }

 

            ERR("VIDIOC_DQBUF failed (%s)\n", strerror(errno));

            breakLoop(THREAD_FAILURE);

        }

 

Call, I tried printing out v4l2buf.timestamp, or the v4l2buf.timecode.tvsecs, v4l2buf.sequence and all show 0!

 

Is there a way around this or a solution to my problem?

 

Thank you

_______________________________________________
Davinci-linux-open-source mailing list
[email protected]
http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source

Reply via email to