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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72" style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal>Good Afternoon All,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I’m looking into IP cameras right now and trying to understand how to accurately determine when a frame was captured. Hopefully some of you all have dealt with this and can give me some guidance? I have a couple different scenarios, each of which I want to be able to know the UTC time of when the frame was captured by the camera or at the very least when the packet hits a Linux box’s kernel.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Scenario 1: USB Camera -> Linux Box 1 via v4l2src.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Scenario 2: USB Camera -> Linux Box 1 via v4l2src -> Network via rtpbin (RTP/RTCP) -> Linux Box 2 via rtpbin.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Scenario 3: GigE Camera RAW Stream -> Linux Box 1 via The Imaging Source element (tcamsrc).<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Scenario 4: GigE Camera RAW Stream -> Linux Box 1 via The Imaging Source element (tcamsrc) -> Network via rtpbin (RTP/RTCP) -> Linux Box 2 via rtpbin.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Scenario 5: IP Camera H264 Stream with NTP Sync every 60min -> Linux Box 1 via rtspsrc element.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Scenario 6: IP Camera H264 Stream with NTP Sync every 60min -> Linux Box 1 via rtspsrc element -> Network via rtpbin (RTP/RTCP) -> Linux Box 2 via rtpbin.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Is what I’m looking for possible in all of these scenarios?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>When using the timeoverlay element, when are time-mode == elapsed-running-time (4) and time-mode == reference-timestamp (5) available?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>When using the identity element with silent=false, is there a way to print to the screen the content of GstBuffers meta data? Seems like from reading this may contain some time elements I’d be interested in?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Can RTP/RTCP/RTSP propagate UTC capture time information or does it get lost early on in the pipeline across multiple Linux boxes?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>All of my systems and the IP Cameras above should be looking at a local NTP Server instance at this point, so hopefully that will help things? It looks like the GigE cameras can’t talk to an NTP server.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thanks!<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Josh Q<o:p></o:p></p></div></body></html>