Hi all,
I have collected all the ideas up to now in a V3 of the agenda and included time allocated for each topic.
The items are grouped by the person(s) that suggested them. As done in the past those who suggested a topic and who will attend the mini-summit are *EXPECTED TO PREPARE FOR IT*. If you present a topic, then make a (small?) presentation if applicable. Those attending should read at least those documents from the presenters that are of special interest to them. We have a full schedule, so let's not waste time. If you have a presentation ready before hand, then just post a link to your presentation so people can read it before the summit.
Please check the time I have allocated for you and let me know if you think it is too short or too long.
We plan to start at 9:00 and we have the room until 17:30 or 18:00 (to be decided). There are breaks from 10:00-10:30, 12:00-13:00, 15:00-15:30. So we have realistically at best around 6 1/2 hours for actual discussions. And that's filled up completely.
The order of the topics is still up in the air. For those marked with 'LP' I would like to have Laurent Pinchart present, but since he is also attending the ARM summit we do not yet know when he will be available. Once I know that I'll shuffle things around to accommodate Laurent.
Laurent, please double check if I marked topics with LP where I shouldn't or vice versa. I have one topic with a 'LP?' prefix where I wasn't really sure.
Topics for the V4L2/DVB mini-summit:
Hans Verkuil: Draft presentation for all these topics: http://hverkuil.home.xs4all.nl/presentations/summit2013.odp
- (LP) Decide on how v4l2 support libraries should be organized. There is code for handling raw-to-sliced VBI decoding, ALSA looping, finding associated video/alsa nodes and for TV frequency tables. We should decide how that should be organized into libraries and how they should be documented. The first two aren't libraries at the moment, but I think they should be. The last two are libraries but they aren't installed. Some work is also being done on an improved version of the 'associating nodes' library that uses the MC if available.
30 min
- (LP?) Define the interaction between selection API, ENUM_FRAMESIZES and S_FMT. See this thread for all the nasty details:
http://www.spinics.net/lists/linux-media/msg65137.html
Also see my draft presentation (link above) for more info and proposals.
60 min
- VIDIOC_TRY_FMT shouldn't return -EINVAL when an unsupported pixelformat is provided, but in practice video capture board tend to do that, while webcam drivers tend to map it silently to a valid pixelformat. Some applications rely on the -EINVAL error code.
We need to decide how to adjust the spec. I propose to just say that some drivers will map it silently and others will return -EINVAL and that you don't know what a driver will do. Also specify that an unsupported pixelformat is the only reason why TRY_FMT might return -EINVAL.
Alternatively we might want to specify explicitly that EINVAL should be returned for video capture devices (i.e. devices supporting S_STD or S_DV_TIMINGS) and 0 for all others.
20 min
- Colorspace: limited/full range
10 min
Mauro Carvalho Chehab:
- Better integration between DVB and V4L2, including starting using the media controller API on DVB side too.
30 min
Laurent Pinchart:
- Status update regarding the media controller API usage on ALSA (Mauro likes to know) and sharing i2c transmitters between V4L2 and DRM (Hans V. likes to know).
10 min
Hugues Fruchet:
- (LP) How to handle codecs where part of the processing is done in HW and part in SW?
2 hours
Sakari Ailus:
- (LP) Multi-format frames and metadata. Support would be needed on video nodes and V4L2 subdev nodes. I'll prepare the RFC for the former; the latter has an RFC here: http://www.spinics.net/lists/linux-media/msg67295.html
50 min
Ricardo Ribalda Delgado, Sylwester Nawrocki:
- Support for multiple rectangle cropping See thread: http://www.spinics.net/lists/linux-media/msg67824.html
20 min
Sylwester Nawrocki
- LED flash support
20 min
Kieran Kunhya
- (3G/HD-)SDI multiplexed raw format
This is a professional interface used in broadcasting and CCTV. The most serious issue is that many vendors provide Linux drivers with V4L2 and ALSA - which is not acceptable for maintaining lipsync, let alone maintaining the exact relationship between audio samples and video that SDI provides.
Some other issues are mentioned here: https://wiki.videolan.org/SDI_API/ The wiki page has a very loose proposal for an API, though perhaps the per-line idea is ambitious at this stage. Field or frame capture is more realistic.
20 min
In principle the agenda is now closed for new topics.
Regards,
Hans