From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-ee0-f46.google.com ([74.125.83.46]:55793 "EHLO mail-ee0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751477Ab2A1RCb (ORCPT ); Sat, 28 Jan 2012 12:02:31 -0500 Received: by mail-ee0-f46.google.com with SMTP id c14so921320eek.19 for ; Sat, 28 Jan 2012 09:02:31 -0800 (PST) Message-ID: <4F242A07.5020602@gmail.com> Date: Sat, 28 Jan 2012 18:01:59 +0100 From: Sylwester Nawrocki MIME-Version: 1.0 To: Sakari Ailus CC: Laurent Pinchart , "HeungJun, Kim" , linux-media@vger.kernel.org, mchehab@redhat.com, hverkuil@xs4all.nl, s.nawrocki@samsung.com, kyungmin.park@samsung.com Subject: Re: [RFC PATCH 0/4] Add some new camera controls References: <1325053428-2626-1-git-send-email-riverful.kim@samsung.com> <201112281501.25091.laurent.pinchart@ideasonboard.com> <4EFD9E10.1050407@gmail.com> <20120104210708.GK9323@valkosipuli.localdomain> In-Reply-To: <20120104210708.GK9323@valkosipuli.localdomain> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Hi everybody, On 01/04/2012 10:07 PM, Sakari Ailus wrote: > On Fri, Dec 30, 2011 at 12:18:40PM +0100, Sylwester Nawrocki wrote: >> Thus we would three levels of controls for camera, >> 1) image source class (lowest possible level), dealing mostly with hardware >> registers; > > I intended the image source class for controls which only deal with the a/d > conversion itself. Other controls would be elsewhere. > > There hasn't been a final decision on this yet, but an alternative which has > been also discussed is just to call this a "low level" control class. > >> 2) "normal" camera controls (V4L2_CID_CAMERA_CLASS) [2]; >> 3) high level camera controls (for camera software algorithms) ... > >> I'm afraid a little it might be hard to distinguish if some control should >> belong to 2) or 3), as sensors' logic complexity and advancement varies. > > I can see two main use cases: > > 1. V4L2 / V4L2 subdev / MC as the low level API for camera control and > > 2. Regular V4L2 applications. > > For most controls it's clear which of the two classes they belong to. Have you any ideas on what the class' name could be ? I thought about V4L2_CTRL_CLASS_HIGH_LEVEL_CAMERA or V4L2_CTRL_CLASS_CAMERA_USER although I'm not too happy with any of them and it seems hard to make up some reasonable name, when we already have V4L2_CTRL_CLASS_CAMERA. >> Although I can see an advantage of logically separating controls which have >> influence on one or more other (lower level) controls. And separate control >> class would be helpful in that. >> >> The candidates to such control class might be: >> >> * V4L2_CID_METERING_MODE, >> * V4L2_CID_EXPOSURE_BIAS, >> * V4L2_CID_ISO, >> * V4L2_CID_WHITE_BALANCE_PRESET, >> * V4L2_CID_SCENEMODE, >> * V4L2_CID_WDR, >> * V4L2_CID_ANTISHAKE, > > The list looks good to me. -- Thanks, Sylwester