Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763481AbXE1WDc (ORCPT ); Mon, 28 May 2007 18:03:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752154AbXE1WDZ (ORCPT ); Mon, 28 May 2007 18:03:25 -0400 Received: from postfix2-g20.free.fr ([212.27.60.43]:56466 "EHLO postfix2-g20.free.fr" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751181AbXE1WDY (ORCPT ); Mon, 28 May 2007 18:03:24 -0400 Message-ID: <465B49EB.4080204@free.fr> Date: Mon, 28 May 2007 23:30:19 +0200 From: Thierry Merle User-Agent: Thunderbird 2.0.0.0 (X11/20070326) MIME-Version: 1.0 To: Mauro Carvalho Chehab CC: Markus Rechberger , video4linux-list@redhat.com, Jiri Slaby , Andrew Morton , linux-kernel@vger.kernel.org Subject: Re: [PATCH 1/1] V4L: stk11xx, add a new webcam driver References: <2172422218943432279@wsc.cz> <1180364420.21547.160.camel@localhost> <1180378677.21547.189.camel@localhost> <1180383071.21547.230.camel@localhost> In-Reply-To: <1180383071.21547.230.camel@localhost> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1825 Lines: 46 Mauro Carvalho Chehab a ?crit : >>> As Luca pointed, if we add conversion for one driver, we should add for >>> the rest. >>> >>> Instead, it would be better if Jiri sends the decoding and the rescaling >>> stuff as a patch to v4l2-apps/lib, starting the API decoding library. >>> Once we have a library, we can ask the userspace developers to use it >>> for the formats not recognized by their userspace apps. >>> >>> >> I think it would be better to evaluate existing solutions (eg. libpw). >> > > Agreed. Volunteers? > > Hi Mauro and Markus, Just to summ up what I understood we need: What do we need in userspace, only for v4l (dvb is not concerned): - colorspace translations - filters that be done in hardware if the selected hardware can, otherwise software plugin - decompression algorithm like stk11xx or usbvision (the decompression algorithm is in kernelspace since it is of linear complexity but shall be moved to userspace) Using pwlib will not mean that application developers will use pwlib to decode v4l driver outputs. C bindings are much more popular than C++ bindings and do not prevent object oriented design. Application developers implement their own codecs. As an example, every application do deinterlacing internally or not... Application developers will probably not use pwlib v4l extensions because they will prefer to write adapted codecs for their framework. Much more important for me is to see the actual specification of the needed v4l extensions points, with advice/participation of application/codec developers. Thierry - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/