Hi Sylwester, On Wed, May 22, 2013 at 11:41:50PM +0200, Sylwester Nawrocki wrote: > [...] > >>>I'm in favour of using a separate video buffer queue for passing > >>>low-level > >>>metadata to user space. > >> > >>Sure. I certainly see a need for such an interface. I wouldn't like to > >>see it > >>as the only option, however. One of the main reasons of introducing > >>MPLANE > >>API was to allow capture of meta-data. We are going to finally prepare > >>some > >>RFC regarding usage of a separate plane for meta-data capture. I'm not > >>sure > >>yet how it would look exactly in detail, we've just discussed this topic > >>roughly with Andrzej. > > > >I'm fine that being not the only option; however it's unbeatable when it > >comes to latencies. So perhaps we should allow using multi-plane buffers > >for the same purpose as well. > > > >But how to choose between the two? > > I think we need some example implementation for metadata capture over > multi-plane interface and with a separate video node. Without such > implementation/API draft it is a bit difficult to discuss this further.
Yes, that'd be quite nice. There are actually a number of things that I think would be needed to support what's discussed above. Extended frame descriptors (I'm preparing RFC v2 --- yes, really!) are one. Also creating video nodes based on how many different content streams there are doesn't make much sense to me. A quick and dirty solution would be to create a low level metadata queue type to avoid having to create more video nodes. I think I'd prefer a more generic solution though. -- Kind regards, Sakari Ailus e-mail: sakari.ai...@iki.fi XMPP: sai...@retiisi.org.uk -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
