<div dir="ltr">Hi Adam,<div> </div><div>I echo Tim's comments...plus, there are a lot of unneeded memory copies occurring in v4l2src which pushes up CPU consumption (30->40% CPU usage per C920 v4l2src instance). I hacked the v4l2src code and was able to get the CPU consumption down to the levels of GStreamer 0.10 v4l2src at about 8->15% CPU usage. I think that there is work being done to rectify this.</div> <div> </div><div>Best Regards,</div><div> </div><div>Rob Krakora</div><div> </div></div><div class="gmail_extra"> <div class="gmail_quote">On Sun, Sep 8, 2013 at 2:17 PM, Tim-Philipp Müller <<a href="mailto:t.i.m@zen.co.uk" target="_blank">t.i.m@zen.co.uk</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On Sun, 2013-09-08 at 21:24 +1200, Adam Goodwin wrote: Hi Adam, > I have a pipeline in a C application which I've noticed doesn't work > smoothly with more than one camera. > > > Currently I'm using two Logitech C920 cameras (with hardware H264 > encoding) in a pipeline which has these branches from the two cameras: > > > v4l2src--->queue--->capsfilter--->h264parse--->tee---> > > > v4l2src--->queue--->capsfilter--->h264parse--->tee---> > > > After the tees, there are these two branches: > > > --->queue--->rtph264pay--->udpsink > > > > --->matroskamux--->queue--->filesink > > > Each tee feeds into the matroskamux branch, which creates a file with > (in this case) two video streams. Only one of the tees is linked to > the network streaming branch at a time (the user can switch the linked > tee when the application runs). > > > What I notice is that the program runs fine, and terminates fine when > the user forces an EOS, but the received video (from over the network, > currently just to 127.0.0.1) has quite a lot of artifacts. > > When I open the resulting MKV file (with VLC) the two video streams > are displayed. However, there are similar artifacts to those seen when > displaying the video live from UDP/RTP. The video also hangs for a few > frames periodically, maybe once every couple of seconds. Finally, the > timing is also wrong for the MKV. > > For example, in a 47 second video, VLC kept track of the current time > correctly up until 8 seconds in. Then the time displayed by VLC got > stuck at 48 seconds(!) while the progress bar for the video continued > to show the correct stream position right up until the video ended > after 47 seconds. > > > None of these problems happen with either the RTP stream or the MKV > file when only one camera is connected and used. (Well, the MKV > playback getting stuck on the same frame every few seconds still > happens, but that's the least of my problems). > > > Does anyone have any ideas what could be wrong? I thought it could be > something to do with not having enough threads, which I've read can be > a problem with a branching pipeline, but each branch has a queue > element so I don't know what else to do. Maybe it's related to <a href="https://bugzilla.gnome.org/show_bug.cgi?id=706083" target="_blank">https://bugzilla.gnome.org/show_bug.cgi?id=706083</a> only that running it with two cameras increases the chances of it happening? Cheers -Tim _______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a> </blockquote></div> <div> </div>-- <div dir="ltr"><table width="426" cellpadding="2" cellspacing="0"><colgroup><col width="422"></colgroup><tbody><tr><td width="422" valign="TOP" style="border:none;padding:0in"> Rob Krakora, Senior Software EngineerMessageNet Systems 101 E Carmel Dr, Suite 105 Carmel, IN 46032 <a href="http://www.messagenetcommunicationsystems.com/?utm_source=email+signature&utm_medium=email&utm_campaign=email+signature+to+homepage" style="color:rgb(17,85,204)" target="_blank">MessageNetSystems.com</a> <a href="mailto:rob.krakora@messagenetsystems.com" style="color:rgb(17,85,204)" target="_blank">Rob.Krakora@MessageNetSystems.com</a> P: <a style="color:rgb(17,85,204)">317.566.1677</a>, 212 F: <a style="color:rgb(17,85,204)">317.663.0808</a></td></tr><tr><td width="422" valign="TOP" style="border-top-width:1px;border-style:solid none none;border-top-color:rgb(0,0,0);padding:0.02in 0in 0in"> For the latest news, information, and blogs, please be sure to visit, follow, and like us...<a href="http://www.messagenetcommunicationsystems.com/get-the-message-out-blog/?utm_source=email+signature&utm_medium=email&utm_campaign=gmail+signature+to+blog" style="color:rgb(17,85,204)" target="_blank"><img src="http://www.messagenetcommunicationsystems.com/wp-content/uploads/2013/07/MessageNet_Logo_200x200-e1374867138718.jpg" name="SafeHtmlFilter_14040bc6244eae96_graphics46" align="BOTTOM" width="34" height="34" border="0"></a> <a href="http://www.youtube.com/user/MessageNetConnection/feed" style="color:rgb(17,85,204)" target="_blank"><img src="http://www.messagenetsystems.com/images/socialmediaicons/32/youtube.png" name="SafeHtmlFilter_14040bc6244eae96_graphics47" align="BOTTOM" width="34" height="34" border="0"></a> <a href="http://www.linkedin.com/company/messagenet-systems" style="color:rgb(17,85,204)" target="_blank"><img src="http://www.messagenetsystems.com/images/socialmediaicons/32/linkedin.png" name="SafeHtmlFilter_14040bc6244eae96_graphics48" align="BOTTOM" width="34" height="34" border="0"></a> <a href="http://twitter.com/MessageNet" style="color:rgb(17,85,204)" target="_blank"><img src="http://www.messagenetsystems.com/images/socialmediaicons/32/twitter.png" name="SafeHtmlFilter_14040bc6244eae96_graphics49" align="BOTTOM" width="34" height="34" border="0"></a> <a href="http://www.facebook.com/MessageNetsystems" style="color:rgb(17,85,204)" target="_blank"><img src="http://www.messagenetsystems.com/images/socialmediaicons/32/facebook.png" name="SafeHtmlFilter_14040bc6244eae96_graphics50" align="BOTTOM" width="34" height="34" border="0"></a> </td></tr></tbody></table></div> </div>