From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from smtp1-g21.free.fr ([212.27.42.1]:49941 "EHLO smtp1-g21.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754798Ab2CPTkE convert rfc822-to-8bit (ORCPT ); Fri, 16 Mar 2012 15:40:04 -0400 Date: Fri, 16 Mar 2012 20:40:05 +0100 From: Jean-Francois Moine To: Xavion Cc: "Linux Kernel (Media) ML" Subject: Re: My Microdia (SN9C201) webcam succumbs to glare in Linux Message-ID: <20120316204005.58f64d41@tele> In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8BIT Sender: linux-media-owner@vger.kernel.org List-ID: On Fri, 16 Mar 2012 08:53:51 +1100 Xavion wrote: > As you can probably gather from the attached screenshots, I'm > attempting to use my SN9C201 webcam for home security.  The problem is > that it succumbs to external glare during the middle hours of sunny > days when used in Linux. > > The same problem doesn't occur in Windows, probably since the software > automatically adjusts to the current lighting conditions.  These > screenshots were taken only five minutes apart and the sunlight > intensity didn't change much in-between. > > No amount of adjusting the webcam's settings (via V4L2-UCP) seemed to > make any significant difference.  For this reason, I'm guessing that > there's at least one other adjustable setting that the GSPCA driver > isn't tapping into yet. [snip] Hi Xavion, It seems that the exposure is not set correctly. May you try the patch below? (to be applied to the gspca test version 2.15.7 - the exposure may be too low at init time, set it to 800) --- build/sn9c20x.c~ +++ build/sn9c20x.c @@ -1650,10 +1650,9 @@ case SENSOR_OV7670: case SENSOR_OV9655: case SENSOR_OV9650: - exp[0] |= (3 << 4); - exp[2] = 0x2d; - exp[3] = expo; - exp[4] = expo >> 8; + exp[0] |= (2 << 4); + exp[2] = 0x10; /* AECH */ + exp[3] = expo * 255 / 0x1780; break; case SENSOR_MT9M001: case SENSOR_MT9V112: -- Ken ar c'hentañ | ** Breizh ha Linux atav! ** Jef | http://moinejf.free.fr/