Thanks, Vaibhav Hiremath > -----Original Message----- > From: linux-media-owner@xxxxxxxxxxxxxxx [mailto:linux-media- > owner@xxxxxxxxxxxxxxx] On Behalf Of Dongsoo Kim > Sent: Sunday, April 19, 2009 12:06 PM > To: Hans Verkuil > Cc: Hiremath, Vaibhav; linux-media@xxxxxxxxxxxxxxx; Aguirre > Rodriguez, Sergio Alberto; Toivonen Tuukka.O (Nokia-D/Oulu); linux- > omap@xxxxxxxxxxxxxxx; Nagalla, Hari; Sakari Ailus; Jadav, Brijesh R; > R, Sivaraj; Hadli, Manjunath; Shah, Hardik; Kumar, Purushotam > Subject: Re: [RFC] Stand-alone Resizer/Previewer Driver support > under V4L2 framework > > Hello Hans and Hiremath, > > One of my recent job is making S3C64XX camera interface driver (even > though other jobs of mine are not finished yet...;-() > And, what a incident! S3C64XX has also similar H/W block in camera > interface. > Resizer in S3C camera interface can be used in system wide like the > one in Omap3. > [Hiremath, Vaibhav] Can you share the spec for the same; I wanted to verify the configuration part of it? What all configuration is exported to the user? > But in case of mine, I decided to make it as a TYPE_VIDEO_CAPTURE > and > TYPE_VIDEO_OUTPUT. > I thought that is was enough. Actually I took omap video out (vout?) > for reference :-) [Hiremath, Vaibhav] I have also implemented the driver is the same way and also working with Hans to get it reviewed. But there are some configuration like coeff., luma enhancement, etc... need to export to the user, where we need to add mechanism in V4L2 framework. Since we have one more device where we are demanding for M-to-M operation, I think it is important to go through it. Can you share some documents of your IP for better understanding. > Cheers, > > Nate > > > 2009. 04. 19, 오전 12:53, Hans Verkuil 작성: > > > On Tuesday 31 March 2009 10:53:02 Hiremath, Vaibhav wrote: > >> Thanks, > >> Vaibhav Hiremath > >> > >>>> APPROACH 3 - > >>>> ---------- > >>>> > >>>> ..... > >>>> > >>>> (Any other approach which I could not think of would be > >>> > >>> appreciated) > >>> > >>>> I would prefer second approach, since this will provide > standard > >>>> interface to applications independent on underneath hardware. > >>>> > >>>> There may be many number of such configuration parameters > required > >>> > >>> for > >>> > >>>> different such devices, we need to work on this and come up > with > >>> > >>> some > >>> > >>>> standard capability fields covering most of available devices. > >>>> > >>>> Does anybody have some other opinions on this? > >>>> Any suggestions will be helpful here, > >>> > >>> FYI: I have very little time to look at this for the next 2-3 > weeks. > >>> As you > >>> know I'm working on the last pieces of the v4l2_subdev > conversion > >>> for 2.6.30 > >>> that should be finished this week. After that I'm attending the > >>> Embedded > >>> Linux Conference in San Francisco. > >>> > >>> But I always thought that something like this would be just a > >>> regular video > >>> device that can do both 'output' and 'capture'. For a resizer I > >>> would > >>> expect that you set the 'output' size (the size of your source > >>> image) and > >>> the 'capture' size (the size of the resized image), then just > send > >>> the > >>> frames to the device (== resizer) and get them back on the > capture > >>> side. > >> > >> [Hiremath, Vaibhav] Yes, it is possible to do that. > >> > >> Hans, > >> > >> I went through the link referred by Sergio and I think we should > >> inherit > >> some implementation for CODECs here for such devices. > >> > >> V4L2_BUF_TYPE_CODECIN - To access the input format. > >> V4L2_BUF_TYPE_CODECOUT - To access the output format. > >> > >> It makes sense, since such memory-to-memory devices will mostly > being > >> used from codecs context. And this would be more clear from user > >> application. > > > > To be honest, I don't see the need for this. I think > > TYPE_VIDEO_CAPTURE and > > TYPE_VIDEO_OUTPUT are perfectly fine. > > > >> And as acknowledged by you, we can use VIDIOC_S_FMT for setting > >> parameters. > >> > >> One thing I am not able to convince myself is that, using "priv" > >> field > >> for custom configuration. > > > > I agree. Especially since you cannot use it as a pointer to > addition > > information. > > > >> I would prefer and recommend capability based > >> interface, where application will query the capability of the > >> device for > >> luma enhancement, filter coefficients (number of coeff and > depth), > >> interpolation type, etc... > >> > >> This way we can make sure that, any such future devices can be > >> adapted by > >> this framework. > > > > The big question is how many of these capabilities are 'generic' > and > > how > > many are very much hardware specific. I am leaning towards using > the > > extended control API for this. It's a bit awkward to implement in > > drivers > > at the moment, but that should improve in the future when a lot of > the > > control handling code will move into the new core framework. > > > > I really need to know more about the sort of features that omap/ > > davinci > > offer (and preferably also for similar devices by other > > manufacturers). > > > >> > >> > >> Hans, > >> Have you get a chance to look at Video-Buf layer issues I > mentioned > >> in > >> original draft? > > > > I've asked Magnus Damm to take a look at this. I know he did some > > work in > > this area and he may have fixed some of these issues already. Very > > useful, > > that Embedded Linux conference... > > > > Regards, > > > > Hans > > > > -- > > Hans Verkuil - video4linux developer - sponsored by TANDBERG > > = > DongSoo, Nathaniel Kim > Engineer > Mobile S/W Platform Lab. > Digital Media & Communications R&D Centre > Samsung Electronics CO., LTD. > e-mail : dongsoo.kim@xxxxxxxxx > dongsoo45.kim@xxxxxxxxxxx > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux- > media" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html ��.n��������+%������w��{.n�����{��g����^n�r������&��z�ޗ�zf���h���~����������_��+v���)ߣ�m
