[Gstreamer-openmax] gst-openmax performance

[pl b. <bos...@gm...>]

Bear with me if this is a known issue, it's been 5 years since I last
looked at OpenMAX IL. Not sure if my ex-colleagues Diego and Giulio
are still in the loop.

I am trying to quantify the overhead due to gst-openmax, compared to
plain old existing gstreamer elements. On an Atom/Ubuntu platform in
ST/GV3off, I get the following residencies:
madplay: 13% C0
gst-launch filesrc ! mad ! audioconvert ! alsasink: 16% C0 (fine)
gst-launch filesrc ! omx_mp3dec ! omx_audiosink: 63% C0 (not good)

Any idea what's happening? All the three configurations rely on the
same libmad and the same test file.

Thanks for your help
Pierre