Dynamic pipeline (videosink swapping)

[Nirbheek Chauhan]

On Mon, Apr 4, 2022 at 8:36 AM Rob Kramer <rob at teegee.cloud> wrote:
> On 3/4/22 00:32, Nirbheek Chauhan via gstreamer-devel wrote:
> > There's a new set of VA-API plugins called "va" in 1.20, which Victor
> > wrote. He is suggesting that you use those instead.
> > https://gitlab.freedesktop.org/gstreamer/gstreamer/-/tree/main/subprojects/gst-plugins-bad/sys/va
>
> Ah OK, thanks. I reconfigured without vaapi and with -Dgst-plugins-bad:va=enabled, but from what I can see in the dot-graph, no va element is used anywhere when playing an mpeg2 video. Is it not detecting my video as mpeg2, or did I misconfigure?
>

playbin uses decodebin, which will autoplug elements that are rank
MARGINAL or higher. The new va decoders are ranked as NONE, since they
are new. To autoplug them, you need to change their rank. This is one
way to do it:

export GST_PLUGIN_FEATURE_RANK=vampeg2dec:257,vah264dec:257,vah265dec:257,vapostproc:257

This will set the rank to PRIMARY+1, which is higher than the vaapi
elements, which will make the app prefer va over vaapi.

Cheers,
Nirbheek