From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from perceval.ideasonboard.com ([95.142.166.194]:42368 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752336Ab1IMKbT (ORCPT ); Tue, 13 Sep 2011 06:31:19 -0400 From: Laurent Pinchart To: Guennadi Liakhovetski Subject: Re: [RFC] New class for low level sensors controls? Date: Tue, 13 Sep 2011 12:31:17 +0200 Cc: Sakari Ailus , linux-media@vger.kernel.org, s.nawrocki@samsung.com, hechtb@googlemail.com References: <20110906113653.GF1393@valkosipuli.localdomain> <20110906122226.GH1393@valkosipuli.localdomain> In-Reply-To: MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201109131231.18178.laurent.pinchart@ideasonboard.com> Sender: linux-media-owner@vger.kernel.org List-ID: Hi Guennadi, On Thursday 08 September 2011 14:35:54 Guennadi Liakhovetski wrote: > On Tue, 6 Sep 2011, Sakari Ailus wrote: > > On Tue, Sep 06, 2011 at 01:41:11PM +0200, Laurent Pinchart wrote: > > > On Tuesday 06 September 2011 13:36:53 Sakari Ailus wrote: [snip] > > > > Typically such sensors are not controlled by general purpose > > > > applications but e.g. require a camera control algorithm framework > > > > in user space. This needs to be implemented in libv4l for general > > > > purpose applications to work properly on this kind of hardware. > > > > > > > > These sensors expose controls such as > > > > > > > > - Per-component gain controls. Red, blue, green (blue) and green > > > > (red) gains. > > > > > > > > - Link frequency. The frequency of the data link from the sensor to > > > > the bridge. > > > > > > > > - Horizontal and vertical blanking. > > > > > > Other controls often found in bayer sensors are black level > > > compensation and test pattern. > > May I suggest a couple more: > > (1) snapshot mode (I really badly want this one, please;-)) What do you mean exactly by snapshot mode ? Is that just external trigger, or does it cover more features than that ? > (2) flash controls (yes, I know we already have V4L2_CTRL_CLASS_FLASH, I > just have the impression, that these controls are mostly meant for > either pure software implementations, or for external controllers, I > think it should also be possible to have them exported by a normal > sensor driver, but wasn't really sure. So, wanted to point out to this > possibility once again.) As Sakari told you in his answer, we can add new controls to the flash class. > (3) AEC / AGC regions This will get tricky. I'm tempted to propose the idea of v4l2_rect controls and control arrays again :-) > (4) stereo (3D anyone?;)) - no, don't think we need it now... -- Regards, Laurent Pinchart