gst_buffer_duration and v4l2src

[Nicolas Dufresne]

Le lundi 19 septembre 2016 à 22:43 +0000, Iván Aponte a écrit :
> Hello, 
> 
> I have a pipeline that is something like this 
> 
> 
> v4l2--->omxh264enc -->queue --> mp4mux --> filesink
> 
> If I put a probe in the queue sink I notice that every buffer comes
> with a duration 0.016666 seconds even though my source is 12 fps
> which is more like 0.083333 seconds each frame. If I put a
> videotestsrc it does output buffers with the duration if 0.083333
> seconds.  Why is this ?

Camera firmware or driver reduce the framerate based on the light
condition. This change is dynamic and is not reported through the Linux
kernel API. In GStreamer, the duration is speculated from the negotiate
framerate (in your case 60 fps). Hence, you cannot trust the duration.
There is an element called videorate that has the capabilities to
adjust those from the timestamp to be perfect.

> 
> Regards, 
> 
> Ivan 
> -- 
> Iván Aponte
> +58 412 2774713
> _______________________________________________
> gstreamer-devel mailing list
> gstreamer-devel at lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel