<html dir="ltr"> <head> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> <style>.EmailQuote { BORDER-LEFT: #800000 2px solid; PADDING-LEFT: 4pt; MARGIN-LEFT: 1pt } </style><style id="owaParaStyle">P { MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px } </style> </head> <body ocsi="0" fPStyle="1"> <div style="FONT-FAMILY: Calibri; DIRECTION: ltr; COLOR: #000000; FONT-SIZE: 12pt"> <p>Hi,</p> <p>Have a look at transport stream carrier. This is used in broadcast to deliver video and audio to be synchronised using a presentation time for decode. The PTS (presentation Time Stamp) ensures that the video and audio are rendered at the correct time. You can use MPEG2<a target="_blank"></a> or h264<a target="_blank"></a> video in a transport stream for the video and normally mpeg or ac3<a target="_blank"></a> audio.</p> <p> </p> <p>There are quite a few options for the mpegts<a target="_blank"></a> plugin<a target="_blank"></a> and maybe other people on the forum will be able to assist.</p> <p> </p> <p>Regards</p> <p>Marc</p> <div> <p> </p> <div style="FONT-FAMILY: Tahoma; FONT-SIZE: 13px"> <div> <p class="MsoNormal"> </p> </div> </div> </div> <div> <hr tabindex="-1"> <div id="x_divRplyFwdMsg"><font color="#000000" size="2" face="Tahoma"><b>From:</b> gstreamer-devel-bounces+marcmltd=marcm.co.uk@lists.freedesktop.org<a target="_blank"></a> [gstreamer-devel-bounces+marcmltd<a target="_blank"></a>=marcm.co.uk@lists.freedesktop.org<a target="_blank"></a>] on behalf of Thomas Levine [occurrence@thomaslevine.com<a target="_blank"></a>]<br> <b>Sent:</b> 07 December 2012 16:41<br> <b>To:</b> Gstreamer<a target="_blank"></a> Devel<a target="_blank"></a><br> <b>Subject:</b> Saving datetimes<a target="_blank"></a> as text<br> </font><br> </div> <div></div> </div> <font size="2"><span style="FONT-SIZE: 10pt"> <div class="PlainText">Hi,<br> <br> I am going to record video, audio and electromyography (It doesn't <br> matter if that<br> means nothing to you.) at the same time, and I want to align the <br> measurements.<br> <br> In case you are curious, I want to figure out why wrists make that <br> cracking noise<br> if you twist them in that weird way that you'll know about only if you <br> do it.<br> Electromyography measures electric potential across a muscle, so it's <br> sort of like<br> muscle activity. More here: <a href="https://github.com/tlevine/wrist-cracking" target="_blank"> https://github.com/tlevine/wrist-cracking</a><br> <br> All of the recording devices are plugged into the same computer, so I <br> think that<br> using clock time would less annoying than some other approaches. Thus, <br> I want to<br> get a datetime<a target="_blank"></a> out of the video and audio that I'm recording.<br> <br> This command seems decent for recording the video and audio.<br> <br> gst<a target="_blank"></a>-launch-0.10 v4l2src<a target="_blank"></a> ! timeoverlay<a target="_blank"></a> halign<a target="_blank"></a>=right valign<a target="_blank"></a>=top ! \<br> clockoverlay<a target="_blank"></a> time-format="%Y-%m-%d %H:%M:%S" halign<a target="_blank"></a>=left <br> valign<a target="_blank"></a>=top ! \<br> video/x-raw-yuv,width<a target="_blank"></a>=640,height<a target="_blank"></a>=480 ! ffmpegcolorspace<a target="_blank"></a> ! <br> theoraenc<a target="_blank"></a> ! \<br> oggmux<a target="_blank"></a> name=mux<a target="_blank"></a> ! filesink<a target="_blank"></a> location="$outfile<a target="_blank"></a>" pulsesrc<a target="_blank"></a> ! <br> audioconvert<a target="_blank"></a> ! \<br> vorbisenc<a target="_blank"></a> ! mux<a target="_blank"></a>.<br> <br> On my computer, the video is laggy<a target="_blank"></a>, but the audio is not, and the audio <br> is more<br> important.<br> <br> This command displays the time as an image, so it's enough for manually <br> aligning<br> the video/audio with the electromyography, but it would be nice if I <br> could make<br> it more automatic. I think that getting the start and end times of the <br> video/audio<br> recording as text would be fine.<br> <br> I've never written anything with gstreamer<a target="_blank"></a> except for hacks with <br> gst<a target="_blank"></a>-launch.<br> It looks like I should use a descendant of GstClock<a target="_blank"></a>, but that's as far <br> as I've<br> gotten. I haven't really written C before.<br> <a href="http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstClock.html" target="_blank">http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gstreamer/html/GstClock.html</a><br> <br> Can I do something like this in gst<a target="_blank"></a>-launch or in something similarly <br> simple?<br> <br> Thanks<br> <br> Tom<br> _______________________________________________<br> gstreamer-devel<a target="_blank"></a> mailing list<br> gstreamer-devel@lists.freedesktop.org<a target="_blank"></a><br> <a href="http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel" target="_blank">http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a><br> </div> </span></font></div> </body> </html>