From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx1.redhat.com ([209.132.183.28]:63736 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753732AbZKSIBW (ORCPT ); Thu, 19 Nov 2009 03:01:22 -0500 Message-ID: <4B04FCF6.2060505@redhat.com> Date: Thu, 19 Nov 2009 09:08:22 +0100 From: Hans de Goede MIME-Version: 1.0 To: Antonio Ospite CC: linux-media@vger.kernel.org, Jean-Francois Moine Subject: Re: [RFC, PATCH] gspca: implement vidioc_enum_frameintervals References: <20091117114147.09889427.ospite@studenti.unina.it> In-Reply-To: <20091117114147.09889427.ospite@studenti.unina.it> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: Hi, On 11/17/2009 11:41 AM, Antonio Ospite wrote: > Hi, > > gspca does not implement vidioc_enum_frameintervals yet, so even if a > camera can support multiple frame rates (or frame intervals) there is > still no way to enumerate them from userspace. > > The following is just a quick and dirty implementation to show the > problem and to have something to base the discussion on. In the patch > there is also a working example of use with the ov534 subdriver. > > Someone with a better knowledge of gspca and v4l internals can suggest > better solutions. > Does the ov534 driver actually support selecting a framerate from the list this patch adds, and does it then honor the selection ? In my experience framerates with webcams are varying all the time, as the lighting conditions change and the cam needs to change its exposure setting to match, resulting in changed framerates. So to me this does not seem very useful for webcams. Regards, Hans