Hi Sylwester, Thanks for the very informative reply!
On Tue, May 1, 2012 at 3:08 PM, Sylwester Nawrocki <snj...@gmail.com> wrote: > Hi Sergio, > > On 05/01/2012 09:08 PM, Aguirre, Sergio wrote: >> Hi all, >> >> I wonder if there's an example app for v4l2 devices with >> V4L2_CAP_VIDEO_CAPTURE_MPLANE capability? >> (like capture.c in V4L2 API docs) > > There isn't at the V4L2 API docs, it probably makes sense to add one though. > I'll try to find a time to prepare a patch for that. A very simple application > with V4L2_CAP_VIDEO_CAPTURE_MPLANE support can be found here: > http://thread.gmane.org/gmane.comp.video.dri.devel/65997 > > It might be not that straightforward since there is the DMABUF memory type > used. Some more applications using multi-plane API are available at: > http://git.infradead.org/users/kmpark/public-apps > > An MMAP memory example can be found here: > http://git.infradead.org/users/kmpark/public-apps/blob/9c057b001e8873861a70f7025214003837a0860b:/v4l2-mfc-example/mfc.c > > Please see mfc_dec_setup_capture function. Thanks. I'll check these links in detail. > >> Also, does it have to be mutually exclusive with a >> V4L2_CAP_VIDEO_CAPTURE device? > > No, the driver could support both. But it generally makes sense to implement > only _mplane ioctls at drivers. The multi/single-plane conversion should be > done in user space. There were some patches for libv4l to support that > (http://www.spinics.net/lists/linux-media/msg35080.html), but such conversions > are not yet supported in the v4l libraries yet AFAIK. Ok. Got it. > > I'm also not sure how is V4L2_CAP_VIDEO_CAPTURE_MPLANE handled in standard > GStreamer plugins like v4l2src at the moment, having only multi-plane > interface at the driver might cause additional problems there. Ok. I guess that's why i was concerned on keeping the non-mplane support coexisting with this. Thanks again for your time! Regards, Sergio > > -- > > Regards, > Sylwester -- 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
