From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail-iw0-f174.google.com ([209.85.214.174]:60082 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756529Ab0GHVdO (ORCPT ); Thu, 8 Jul 2010 17:33:14 -0400 Received: by iwn7 with SMTP id 7so1326915iwn.19 for ; Thu, 08 Jul 2010 14:33:14 -0700 (PDT) Message-ID: <4C364416.3000809@gmail.com> Date: Thu, 08 Jul 2010 17:33:10 -0400 From: Ivan MIME-Version: 1.0 To: Devin Heitmueller CC: linux-media@vger.kernel.org Subject: Re: em28xx: success report for KWORLD DVD Maker USB 2.0 (VS-USB2800) [eb1a:2860] References: <4C353039.4030202@gmail.com> <4C360E64.3020703@gmail.com> <4C362C6E.5050104@gmail.com> <4C363692.5000600@gmail.com> In-Reply-To: <4C363692.5000600@gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-media-owner@vger.kernel.org List-ID: On 07/08/2010 04:35 PM, Ivan wrote: > On 07/08/2010 04:02 PM, Devin Heitmueller wrote: >> On Thu, Jul 8, 2010 at 3:52 PM, Ivan wrote: >>> Yep, that gets rid of the vertical stripes but adds in a lovely >>> horizontal >>> shift: >>> >>> http://www3.picturepush.com/photo/a/3763906/img/3763906.png >> >> The "horizontal shift" issue is interesting. Does that happen every >> time? And did you unplug/replug the device? Try to reboot? > > Reboot? What is this, Windoze? :^D > > But yeah, it's consistent across unplugs/replugs/reboots. Ok, the horizontal shift disappears if I switch to 720x480 instead of 640x480. Does the card always output 720x480 (in NTSC mode anyway), then, and any scaling is done by V4L? I also have a question about dropped frames. After running mplayer or mencoder, I see a line like: v4l2: 1199 frames successfully processed, -3 frames dropped. I can only guess that the negative number means that V4L received frames at a slightly faster rate than the expected 30000/1001 fps. In my case, it would seem that my SNES is producing something more like 30.05 fps, and so V4L reports a "negative" dropped frame every 12.5 seconds or so. It would also seem that V4L doesn't actually discard any frames, but still passes them on to mplayer/mencoder, because mencoder shows an encoding fps of 30.04 (and it will skip a frame every 12.5 seconds or so unless you pass it -noskip). Am I right about all this? Ivan