From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:32938) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S9nbp-0002yo-Ry for qemu-devel@nongnu.org; Mon, 19 Mar 2012 21:11:35 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1S9nbV-0006xD-VB for qemu-devel@nongnu.org; Mon, 19 Mar 2012 21:11:33 -0400 Received: from mail-yw0-f45.google.com ([209.85.213.45]:57144) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1S9nbV-0006x1-OR for qemu-devel@nongnu.org; Mon, 19 Mar 2012 21:11:13 -0400 Received: by yhoo21 with SMTP id o21so6982163yho.4 for ; Mon, 19 Mar 2012 18:11:12 -0700 (PDT) Message-ID: <4F67D92C.6040203@gmail.com> Date: Mon, 19 Mar 2012 22:11:08 -0300 From: Rafael da Veiga Cabral MIME-Version: 1.0 References: <4F67A0CC.1030009@codemonkey.ws> In-Reply-To: <4F67A0CC.1030009@codemonkey.ws> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] [PATCH] PNG screendump alternative List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: qemu-devel@nongnu.org On 03/19/2012 06:10 PM, Anthony Liguori wrote: > On 03/17/2012 05:45 PM, Rafael wrote: >> Hi, >> >> I had already started to work on supporting PNG dump output on >> screendump when got to know there was another effort to do the same >> (see Add PNG screendump thread from Daniel P. Berrange). Anyway, I'd >> like to share my implementation which is a little bit different. It >> does not use any resource/lib besides libpng and qemu itself and is >> based on qemu-kvm 0.15.1 ppm_save code. >> >> I'm using that for a personal project developed at Mandriva which uses >> QMP directly to communicate with qemu VMs rather than using the >> libvirt although its usage is considered for the future. There is >> something more to show but it is just QMP related and soon I'll have >> it done to share. >> >> Comments and suggestions are appreciated. > > I think the added value of this is minimal compared to the alternative > implementation (just run convert on the PPM). > > Can you talk a bit more about your use-case any why post-processing > the PPM isn't a reasonable alternative? > It's because my use-case requires a screenshoot on each second or less. It's a functional testing tool based on what is happening on the vm screen. The testing stuff is based on basic image processing of the screens. Therefore as screen are grabbed all time the less CPU and Disk I/O are required the better, for example, by changing from PPM to PNG at least 2.2 Megas of disk writing are saved on each second. Think about a session of 15 minutes or more (15 * 60 * 2.2). I've also thought that by saving directly from the screen buffer to png should save some CPU cycles rather than saving to PPM first and converting it to PNG on the qemu runtime. > Regards, > > Anthony Liguori > >> >> Cheers >> Rafael Cabral > Thanks Anthony Rafael Cabral