<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN">
<html><body style='font-family: Verdana,Geneva,sans-serif'>
<div>Hi,</div>
<div> </div>
<div>To my understanding, `<span style="font-family: Calibri, sans-serif; font-size: 11pt;">buffer->get_pts()` makes little sense in case of MPEG-TS as each GStreamer buffer will typically hold a number of TS packets which in turn can be part of different PES packets and elementary streams and relate to different access units (frames). So I do not find it particularly useful to indicate with GStreamer PTS when to "present" such ambiguous chunk of stream before demuxing it.</span></div>
<div><span style="font-family: Calibri, sans-serif; font-size: 11pt;"> </span></div>
<div><span style="font-family: Calibri, sans-serif; font-size: 11pt;">Also to my understanding information like TOT/TDT is more useful when presenting programme events (EIT) for example in a guide and to synchronise intended start date and time of the events with the local time (for presentation or recording purposes). I can't see how it could be useful to relate it to the actual media time where it's not really useful to <span id="-x-evo-selection-start-marker"></span><span id="-x-evo-selection-end-marker"></span>care about absolute values especially when timestamps can wrap.</span></div>
<div><span style="font-family: Calibri, sans-serif; font-size: 11pt;"> </span></div>
<div><span style="font-family: Calibri, sans-serif; font-size: 11pt;">Kris</span></div>
<div><span style="font-family: Calibri, sans-serif; font-size: 11pt;"> </span></div>
<div>On Fri, 2018-05-04 at 07:13 +0000, Adams, Bruce (KMLWG) wrote:</div>
<blockquote type="cite" style="padding-left:5px; border-left:#1010ff 2px solid; margin-left:5px">
<div class="WordSection1">
<p class="MsoNormal">Hi,</p>
<p class="MsoNormal"> I am trying to work out how to get absolute time-stamps from an incoming MPEG transport stream.</p>
<p class="MsoNormal">The basics seem to be that we get a presentation time-stamp via buffer->get_pts(). This is relative to the program clock reference PCR which is dictated by one of the elementary streams – typically the video. How do I get that base time out of gstreamer?</p>
<p class="MsoNormal">I note that if I use a tsparse element it can decode TOT and TDT sections for DVB inputs. However, I also notice that one of my inputs is a TSIP input which does not include these sections.</p>
<p class="MsoNormal">How can I tell if an absolute time reference is available and when it is what is the epoch? Is it the standard unix epoch 1970-01-01T00:00:00Z?</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Regards,</p>
<p class="MsoNormal"> </p>
<p class="MsoNormal">Bruce.</p>
</div>
<br /><br /><a href="http://www.kantar.com/disclaimer.html">Kantar Disclaimer</a>
<pre>_______________________________________________
gstreamer-devel mailing list
<a href="mailto:gstreamer-devel@lists.freedesktop.org">gstreamer-devel@lists.freedesktop.org</a>
<a href="https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel">https://lists.freedesktop.org/mailman/listinfo/gstreamer-devel</a>
</pre>
</blockquote>
<div class="-x-evo-signature-wrapper"> </div>
</body></html>