[Bug 583890] v4l2: Implement V4L2_MEMORY_USERPTR support

[GStreamer (bugzilla.gnome.org)]

https://bugzilla.gnome.org/show_bug.cgi?id=583890
  GStreamer | gst-plugins-good | git

Aurélien Zanelli <aurelien.zanelli> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |aurelien.zanelli at parrot.com

--- Comment #39 from Aurélien Zanelli <aurelien.zanelli at parrot.com> 2013-12-31 12:02:09 UTC ---
Hi,

I've also works on user pointer support for v4l2/v4l2sink.
My first goal was to enable a zero copy path between gst-omx and v4l2sink. In
this case, buffers are allocated by the video decoder (hardware allocated
contiguous memory) and provided to v4l2sink.

I wrote a hack based on gst-plugins-good 1.2 branch (rebased from 1.2.2
release) for its purpose.
It enables USERTPR mode for output video only. It tracks incoming buffer across
qbuf/dqbuf mechanisms by using V4l2Meta structure.
Also in case the upstream element uses v4l2bufferpool, buffers are allocated in
userspace, but some devices requires memory alignment and/or contiguous memory
as said in previous post, so it could fail.

Also i could test other patch about this topic. Feel free to ask questions.

Regards,

-- 
Configure bugmail: https://bugzilla.gnome.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the QA contact for the bug.