From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-la0-f44.google.com ([209.85.215.44]:36205 "EHLO mail-la0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751417AbbG3P0C (ORCPT ); Thu, 30 Jul 2015 11:26:02 -0400 Received: by lagw2 with SMTP id w2so27334057lag.3 for ; Thu, 30 Jul 2015 08:26:00 -0700 (PDT) Date: Thu, 30 Jul 2015 18:25:56 +0300 From: Paul Fertser To: Laurent Pinchart Cc: Peter Rabbitson , linux-media@vger.kernel.org Subject: Re: [PATCH] uvcvideo: Disable hardware timestamps by default Message-ID: <20150730152555.GS18455@home.paul.comp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1438006696-30678-1-git-send-email-laurent.pinchart@ideasonboard.com> Sender: linux-media-owner@vger.kernel.org List-ID: Hello Laurent, I was experimenting with a web-camera integrated in my laptop and was extremely confused by non-monotonic timestamps coming from the uvc driver. In fact, the very first timestamp was bigger then the second every time I tried. This patch helped. More details: 1. I'm testing with avconv -f video4linux2 -i /dev/video0 -codec copy test.mkv 2. Prior to applying the patch I was always getting "Non-monotonous DTS in output stream 0:0" errors 3. I'm using kernel version 3.6.8 (yes, that's old, I'm ready to upgrade if you really need that for debugging) 4. The camera is 5986:0100 Acer, Inc Orbicam Anything else I can do to help you with this issue? My real usecase is having a single-board computer capturing a steady stream from a UVC webcam (h264 pixel format) while keeping timestamps reasonably accurate (within 0.1s) for the future processing and spending as little CPU time as possible. Thank you in advance. -- Be free, use free (http://www.gnu.org/philosophy/free-sw.html) software! mailto:fercerpav@gmail.com