Fast decode h264 stream, keyframes only.

[Tim Müller]

On Sat, 2017-03-11 at 11:20 -0500, Nicolas Dufresne wrote:

> > Can gstreamer fast decode h264/5 steam and return only keyframes?
> > That would be usefull for opencv processing  of live streams.
> 
> I believe this should work in recent version with the
> GST_SEEK_FLAG_KEY_UNIT. Pause you streamr, and then operate a
> flushing seek with this flag set.

You probably meant GST_SEEK_FLAG_TRICKMODE_KEY_UNITS ? :)

Question is, what does one do when seeking is not supported? In that
case one would have to add a pad probe on the decoder sink pad or
parser src pad or so and drop all frames that are flagged as delta
units via the buffer flags or such.

Theoretically a seek without start/stop position change to just change
the flags should work too, but I wouldn't bet on it :)

Cheers
 -Tim

-- 
Tim Müller, Centricular Ltd - http://www.centricular.com