Hi Jean-Michel,

Am Donnerstag, den 18.12.2014, 17:55 +0100 schrieb Jean-Michel Hautbois:
> Hi Philipp,
> 
> 2014-12-18 17:52 GMT+01:00 Philipp Zabel <p.za...@pengutronix.de>:
> > Hi Frédéric,
> >
> > Am Donnerstag, den 18.12.2014, 17:44 +0100 schrieb Frédéric Sureau:
> >> Hi
> >>
> >> I am trying to use the coda encoder through Gstreamer on an iMX6-based
> >> board.
> >>
> >> I use the (rebased and slightly modified) gstv4l2h264enc plugin from:
> >> https://github.com/hizukiayaka/gst-plugins-good
> >>
> >> This pipeline works fine:
> >> gst-launch-1.0 -vvv v4l2src device=/dev/video4 !
> >> "video/x-raw,width=1280,height=720" ! videoconvert ! v4l2video0h264enc !
> >> h264parse ! mp4mux ! filesink location=test.mp4
> >>
> >> When encoder has no bitrate param set (default=0), video encoding works
> >> well, but bitrate reaches ~2.5Mbps
> >>
> >> When I try to set the bitrate with whatever value like 100,000 or
> >> 1,000,000, the encoder produces video with bitrate around 480kbps and a
> >> very poor quality.
> >>
> >> Here is the gstreamer pipeline I use with bitrate set:
> >> gst-launch-1.0 -vvv v4l2src device=/dev/video4 !
> >> "video/x-raw,width=1280,height=720" ! videoconvert ! v4l2video0h264enc
> >> extra-controls="controls,video_bitrate=1000000;" ! h264parse ! mp4mux !
> >> filesink location=test.mp4
> >>
> >> The video_bitrate control seems to be correctly passed to the driver by
> >> GStreamer since I can see the VIDIOC_S_CTRL call.
> >>
> >> Any idea ?
> >
> > There is a bug in the register definitions that causes the driver to
> > apply a wrong mask before writing the bitrate to the register.
> > I've got a fix for this in the pipeline, sending it right now.
> 
> Where can we find the register definitions ? In order to look at it
> before asking you :) ?

Sorry, forgot to put all of you on Cc: for the "[media] coda: fix
encoder rate control parameter masks" patch. The coda driver is in
drivers/media/platform/coda, register definitions in coda_regs.h.
The CODA_RATECONTROL_BITRATE_MASK is 0x7f, but it should be 0x7fff.

regards
Philipp

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