From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from perceval.ideasonboard.com ([95.142.166.194]:58325 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754826Ab1L3ALC (ORCPT ); Thu, 29 Dec 2011 19:11:02 -0500 From: Laurent Pinchart To: "HeungJun, Kim" Subject: Re: [RFC PATCH 2/4] v4l: Add V4L2_CID_SCENEMODE menu control Date: Fri, 30 Dec 2011 01:11:08 +0100 Cc: linux-media@vger.kernel.org, mchehab@redhat.com, hverkuil@xs4all.nl, sakari.ailus@iki.fi, s.nawrocki@samsung.com, kyungmin.park@samsung.com References: <1325053428-2626-1-git-send-email-riverful.kim@samsung.com> <201112281456.05515.laurent.pinchart@ideasonboard.com> <001201ccc5ec$709ca6d0$51d5f470$%kim@samsung.com> In-Reply-To: <001201ccc5ec$709ca6d0$51d5f470$%kim@samsung.com> MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <201112300111.09581.laurent.pinchart@ideasonboard.com> Sender: linux-media-owner@vger.kernel.org List-ID: Hi, On Thursday 29 December 2011 06:40:57 HeungJun, Kim wrote: > On Wednesday, December 28, 2011 10:56 PM Laurent Pinchart wrote: > > On Wednesday 28 December 2011 07:23:46 HeungJun, Kim wrote: [snip] > > > diff --git a/Documentation/DocBook/media/v4l/controls.xml > > > b/Documentation/DocBook/media/v4l/controls.xml index 350c138..afe1845 > > > 100644 > > > --- a/Documentation/DocBook/media/v4l/controls.xml > > > +++ b/Documentation/DocBook/media/v4l/controls.xml > > > @@ -2879,6 +2879,94 @@ it one step further. This is a write-only > > > control. > > > > > > > > > > > > + > > > + > > spanname="id">V4L2_CID_SCENEMODE  + > > > enum v4l2_scenemode > > > + This control sets > > > + the camera's scenemode, and it is provided by the type of > > > + the enum values. The "None" mode means the status > > > + when scenemode algorithm is not activated, like after booting > > > time. > > > + On the other hand, the "Normal" mode means the scenemode algorithm > > > + is activated on the normal mode. > > > > What low-level parameters do the scene mode control ? How does it > > interact with the related controls ? > > For using this control, in M-5MOLS sensor case, several register is > configured, like Exposure(locking/Indexed preset/mode), Focus(locking), > WhiteBalance, etc. And I think the process interacting and syncing the > register's value should be up to the each drivers, and the m5mols driver > will be. Does it mean that the scene mode is handled by the driver, which then configures exposure, focus, white balance, ... ? > Anyways, could you explain the difference with low- and high- in more > details? > > :) > > I still did not understand well. The concepts are a bit ill-defined currently. We have low-level sensor controls such as exposure time, gains, ... The controls you propose offer a higher level interface, likely using software-based algorithms running on the sensor instead of just applying hardware parameters. > > > + > > > + > > > + > > > + > > > + > > > + V4L2_SCENEMODE_NONE  > > > + Scenemode None. > > > + > > > + > > > + > > V4L2_SCENEMODE_NORMAL  > > > > + Scenemode Normal. > > > + > > > + > > > + > > > > V4L2_SCENEMODE_PORTRAIT  > > > > > + Scenemode Portrait. > > > > Could you please describe the scene modes in more details ? > > Yes, the photographer should adjust the exposure(luminance), focus, iso, > etc, for getting better image according to each specific circumstances. > But, it's uncomfortable to set all controls at every time. > The scene mode can make this at one time. It is just not only setting once. > According to fixed scene circumstance, the internal algorithm is also > needed for it. > > This function is usually provided as just preset, but, it's not just > preset, because the specific algorithm is existed for "scene mode", > except the collection of the camera control preset. > > The enumeration I suggest, can cover almost scene mode. Of course, the term > is fixed. The M-5MOLS can use all the scene mode. > Please, see drivers/media/video/m5mols/m5mols_contro.c. What I meant when asking you to explain the scene modes in more details was to improve the documentation by adding a detailed description of each scene mode. -- Regards, Laurent Pinchart