From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mx3.redhat.com (mx3.redhat.com [172.16.48.32]) by int-mx1.corp.redhat.com (8.13.1/8.13.1) with ESMTP id m7EHOHwM011251 for ; Thu, 14 Aug 2008 13:24:17 -0400 Received: from smtp5-g19.free.fr (smtp5-g19.free.fr [212.27.42.35]) by mx3.redhat.com (8.13.8/8.13.8) with ESMTP id m7EHO8rh019168 for ; Thu, 14 Aug 2008 13:24:08 -0400 From: Jean-Francois Moine To: Hans de Goede Content-Type: text/plain; charset=ISO-8859-1 Date: Thu, 14 Aug 2008 19:14:05 +0200 Message-Id: <1218734045.1696.39.camel@localhost> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Cc: Video 4 Linux Subject: v4l library - decoding of Pixart JPEG frames List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: video4linux-list-bounces@redhat.com Errors-To: video4linux-list-bounces@redhat.com List-ID: Hello Hans, I found that the webcams containing a Pixart JPEG chip (PAC 73xx) generate strange JPEG frames: they contains 'ff ff ff xx' markers every 1024 or 512 bytes and there are eight unused bits at the end of each JPEG block (I saw also a 90 degrees rotation with the PAC 7302). So, I added a new pixel format V4L2_PIX_FMT_PJPG for this encoding. It is generated by the pac7311 subdriver of gspca. May you add the code for decoding this format in the V4L library? I could have done a patch by myself, but the tiny jpeg decoder is rather complex, and I could not find the right place to do the job. If it may help, I wrote a simple image viewer (http://moinejf.free.fr/siv.c) which takes a raw webcam image and displays it via gtk+. It contains the Pixart JPEG decoder and the two differences from normal JPEG are identified by 'pac7311'. Cheers. -- Ken ar c'hentań | ** Breizh ha Linux atav! ** Jef | http://moinejf.free.fr/ -- video4linux-list mailing list Unsubscribe mailto:video4linux-list-request@redhat.com?subject=unsubscribe https://www.redhat.com/mailman/listinfo/video4linux-list