gstclock and absolute time
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Dear all,
How can I convert gst_clock_get_time() value in an absolute time (with year, month, day, ....). I'm playing with an rtsp camera, using rtspsrc, and I would like to retrieve absolute time (ntp stream time) across my pipeline. Is there an easy way to do that? from element's clock time now (=Tue Jun 26 12:03:34 CEST 2012) I get something like: 6112256969101111 and it contains a bunch of thousands of seconds.... I'm a little bit puzzled. BR, pz _______________________________________________ gstreamer-devel mailing list [hidden email] http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
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Tried using ! clockoverlay ! ? Or do you need the time that the
image is encoded ? Richard On 26 June 2012 11:06, Pazzo Da Legare <[hidden email]> wrote: > Dear all, > > How can I convert gst_clock_get_time() value in an absolute time (with > year, month, day, ....). I'm playing with an rtsp camera, using > rtspsrc, and I would like to retrieve absolute time (ntp stream time) > across my pipeline. Is there an easy way to do that? > > from element's clock time now (=Tue Jun 26 12:03:34 CEST 2012) I get > something like: > > 6112256969101111 > > and it contains a bunch of thousands of seconds.... > > I'm a little bit puzzled. > > BR, > > pz > _______________________________________________ > gstreamer-devel mailing list > [hidden email] > http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel gstreamer-devel mailing list [hidden email] http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
Re: gstclock and absolute time
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Hi Richard,
Yes I need the source time (encoded time) :-) Regards, pz 2012/6/26 Richard <[hidden email]>: > Tried using ! clockoverlay ! ? Or do you need the time that the > image is encoded ? > > Richard > > On 26 June 2012 11:06, Pazzo Da Legare <[hidden email]> wrote: >> Dear all, >> >> How can I convert gst_clock_get_time() value in an absolute time (with >> year, month, day, ....). I'm playing with an rtsp camera, using >> rtspsrc, and I would like to retrieve absolute time (ntp stream time) >> across my pipeline. Is there an easy way to do that? >> >> from element's clock time now (=Tue Jun 26 12:03:34 CEST 2012) I get >> something like: >> >> 6112256969101111 >> >> and it contains a bunch of thousands of seconds.... >> >> I'm a little bit puzzled. >> >> BR, >> >> pz >> _______________________________________________ >> gstreamer-devel mailing list >> [hidden email] >> http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel > _______________________________________________ > gstreamer-devel mailing list > [hidden email] > http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel gstreamer-devel mailing list [hidden email] http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
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In reply to this post by Pazzo Da Legare
On Tue, Jun 26, 2012 at 6:06 AM, Pazzo Da Legare
<[hidden email]> wrote: > Dear all, > > How can I convert gst_clock_get_time() value in an absolute time (with > year, month, day, ....). I'm playing with an rtsp camera, using > rtspsrc, and I would like to retrieve absolute time (ntp stream time) > across my pipeline. Is there an easy way to do that? > > from element's clock time now (=Tue Jun 26 12:03:34 CEST 2012) I get > something like: > > 6112256969101111 > > and it contains a bunch of thousands of seconds.... > > I'm a little bit puzzled. gst_clock_get_time() will just give you a monotonically increasing integer. Subtracting the base time from that will give you the stream time: http://gstreamer.freedesktop.org/data/doc/gstreamer/head/manual/html/chapter-clocks.html If you're talking about the ISO 8601 timestamps that indicate the absolute UTC time, this doesn't appear to be implemented currently: http://cgit.freedesktop.org/gstreamer/gst-plugins-base/tree/gst-libs/gst/rtsp/gstrtsprange.c#n249 http://tools.ietf.org/html/rfc2326#page-18 A few issues. Not all servers support absolute time ranges. You can only get an absolute time if you requested the range in the same format, so rtspsrc would need to be given this information. Or you could extract a time range from SDP. Either way, you'd need a way to get the time to the application. This last part is what I'm interested. For now I'm sending a GST_TAG_DATE_TIME event to indicate the start time of the stream, so a buffer absolute time can be calculated from this absolute time and the stream time. If there's a better way (GstMeta?) then I'd like to hear it. -Josh _______________________________________________ gstreamer-devel mailing list [hidden email] http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
Re: gstclock and absolute time
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Dear Josh,
Thank you very much for your links. I thought I couldn't find the right parameter to instruct rtspsrc to propagate the time downstream (or better to say to use the rtsp source time as clock reference) I was more than sure that it would have been possible, but now you confirm that a "crazy" idea to manage sr-message is the only (known) way to extract source reference: I'm trying to follow exactly the same approach trying to extract absolute time from rtspsrc and send a metadata event (GST_EVENT_TAG) through my pipeline. The point is how to correlate internal absolute time (what you can get with gst_clock_get_time()) and ntptime of RTCP protocol without _error_ (i.e. taking into account source->rtspsrc transmission time)? I can intercept RtpSession information but I have no way to relate (sr-ntptime, sr-rtptime) with the time (internal absolute time) of the frame they are referring to. Any clue? BR, pz 2012/6/26 Josh Doe <[hidden email]>: > On Tue, Jun 26, 2012 at 6:06 AM, Pazzo Da Legare > <[hidden email]> wrote: >> Dear all, >> >> How can I convert gst_clock_get_time() value in an absolute time (with >> year, month, day, ....). I'm playing with an rtsp camera, using >> rtspsrc, and I would like to retrieve absolute time (ntp stream time) >> across my pipeline. Is there an easy way to do that? >> >> from element's clock time now (=Tue Jun 26 12:03:34 CEST 2012) I get >> something like: >> >> 6112256969101111 >> >> and it contains a bunch of thousands of seconds.... >> >> I'm a little bit puzzled. > > gst_clock_get_time() will just give you a monotonically increasing > integer. Subtracting the base time from that will give you the stream > time: > http://gstreamer.freedesktop.org/data/doc/gstreamer/head/manual/html/chapter-clocks.html > > If you're talking about the ISO 8601 timestamps that indicate the > absolute UTC time, this doesn't appear to be implemented currently: > http://cgit.freedesktop.org/gstreamer/gst-plugins-base/tree/gst-libs/gst/rtsp/gstrtsprange.c#n249 > http://tools.ietf.org/html/rfc2326#page-18 > > A few issues. Not all servers support absolute time ranges. You can > only get an absolute time if you requested the range in the same > format, so rtspsrc would need to be given this information. Or you > could extract a time range from SDP. Either way, you'd need a way to > get the time to the application. > > This last part is what I'm interested. For now I'm sending a > GST_TAG_DATE_TIME event to indicate the start time of the stream, so a > buffer absolute time can be calculated from this absolute time and the > stream time. If there's a better way (GstMeta?) then I'd like to hear > it. > > -Josh > _______________________________________________ > gstreamer-devel mailing list > [hidden email] > http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel gstreamer-devel mailing list [hidden email] http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
Re: gstclock and absolute time
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Dear Josh,
I want just to add a bit of info. I'm trying to understand how to correlate data from signal "handle-sync" (http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-good-plugins/html/gst-plugins-good-plugins-gstrtpjitterbuffer.html#GstRtpJitterBuffer-handle-sync) of GstRtpJitterBuffer and "stats" of rtpsession but I really don't understand what base-time is.... This is what I get from GstRtpJitterBuffer "handle-sync" signal: application/x-rtp-sync, base-rtptime=(guint64)2490599386, base-time=(guint64)137714729, clock-rate=(uint)90000, sr-ext-rtptime=(guint64)2491725922, sr-buffer=(buffer)80c800069af6cadbd39457a5e959817b9484b862000003ed0010b1da81ca000c9af6cadb0116726f6f7440616f63632d617869732d646f6d656f6c640204726f6f7406094753747265616d6572000000; and at the same time from rtpsource "stats": application/x-rtp-source-stats, ssrc=(uint)2599865051, internal=(boolean)false, validated=(boolean)true, received-bye=(boolean)false, is-csrc=(boolean)false, is-sender=(boolean)true, seqnum-base=(int)-1, clock-rate=(int)90000, rtp-from=(string)192.168.3.27:50088, rtcp-from=(string)192.168.3.27:50089, octets-sent=(guint64)0, packets-sent=(guint64)0, octets-received=(guint64)1155650, packets-received=(guint64)1060, bitrate=(guint64)703428, packets-lost=(int)0, jitter=(uint)83, have-sr=(boolean)true, sr-ntptime=(guint64)15245907008652149115, sr-rtptime=(uint)2491725922, sr-octet-count=(uint)1094106, sr-packet-count=(uint)1005, sent-rb=(boolean)true, sent-rb-fractionlost=(uint)0, sent-rb-packetslost=(int)0, sent-rb-exthighestseq=(uint)18120, sent-rb-jitter=(uint)97, sent-rb-lsr=(uint)1470108312, sent-rb-dlsr=(uint)337017, have-rb=(boolean)false, rb-fractionlost=(uint)0, rb-packetslost=(int)0, rb-exthighestseq=(uint)0, rb-jitter=(uint)0, rb-lsr=(uint)0, rb-dlsr=(uint)0, rb-round-trip=(uint)0; Does anybody know how to obtain the damn time reference from sr-rtptime/sr-ntptime to pipeline "absolute time" (aka the one defined here http://cgit.freedesktop.org/gstreamer/gstreamer/tree/docs/design/part-synchronisation.txt)? TIA, pz 2012/6/26 Pazzo Da Legare <[hidden email]>: > Dear Josh, > > Thank you very much for your links. > > I thought I couldn't find the right parameter to instruct rtspsrc to > propagate the time downstream (or better to say to use the rtsp source > time as clock reference) I was more than sure that it would have been > possible, but now you confirm that a "crazy" idea to manage sr-message > is the only (known) way to extract source reference: I'm trying to > follow exactly the same approach trying to extract absolute time from > rtspsrc and send a metadata event (GST_EVENT_TAG) through my pipeline. > The point is how to correlate internal absolute time (what you can get > with gst_clock_get_time()) and ntptime of RTCP protocol without > _error_ (i.e. taking into account source->rtspsrc transmission time)? > > I can intercept RtpSession information but I have no way to relate > (sr-ntptime, sr-rtptime) with the time (internal absolute time) of the > frame they are referring to. Any clue? > > BR, > pz > > > > > 2012/6/26 Josh Doe <[hidden email]>: >> On Tue, Jun 26, 2012 at 6:06 AM, Pazzo Da Legare >> <[hidden email]> wrote: >>> Dear all, >>> >>> How can I convert gst_clock_get_time() value in an absolute time (with >>> year, month, day, ....). I'm playing with an rtsp camera, using >>> rtspsrc, and I would like to retrieve absolute time (ntp stream time) >>> across my pipeline. Is there an easy way to do that? >>> >>> from element's clock time now (=Tue Jun 26 12:03:34 CEST 2012) I get >>> something like: >>> >>> 6112256969101111 >>> >>> and it contains a bunch of thousands of seconds.... >>> >>> I'm a little bit puzzled. >> >> gst_clock_get_time() will just give you a monotonically increasing >> integer. Subtracting the base time from that will give you the stream >> time: >> http://gstreamer.freedesktop.org/data/doc/gstreamer/head/manual/html/chapter-clocks.html >> >> If you're talking about the ISO 8601 timestamps that indicate the >> absolute UTC time, this doesn't appear to be implemented currently: >> http://cgit.freedesktop.org/gstreamer/gst-plugins-base/tree/gst-libs/gst/rtsp/gstrtsprange.c#n249 >> http://tools.ietf.org/html/rfc2326#page-18 >> >> A few issues. Not all servers support absolute time ranges. You can >> only get an absolute time if you requested the range in the same >> format, so rtspsrc would need to be given this information. Or you >> could extract a time range from SDP. Either way, you'd need a way to >> get the time to the application. >> >> This last part is what I'm interested. For now I'm sending a >> GST_TAG_DATE_TIME event to indicate the start time of the stream, so a >> buffer absolute time can be calculated from this absolute time and the >> stream time. If there's a better way (GstMeta?) then I'd like to hear >> it. >> >> -Josh >> _______________________________________________ >> gstreamer-devel mailing list >> [hidden email] >> http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel gstreamer-devel mailing list [hidden email] http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
Re: gstclock and absolute time
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Hi all again,
Probably I found something interesting activating log for "rtpbin": GST_DEBUG=rtpbin:5 gst-launch --gst-debug-no-color rtspsrc location=rtsp://192.168.3.27/axis-media/media.amp?audio=0 latency=200 ! rtph264depay ! ffdec_h264 ! ffmpegcolorspace ! shmframeserver latency=200 ! ffmpegcolorspace ! fakesink http://pastebin.com/ZqaN09MQ it seems that rtpbin cannot read localtime....any clue? Is it a bug? BR, pz 2012/6/26 Pazzo Da Legare <[hidden email]>: > Dear Josh, > > I want just to add a bit of info. I'm trying to understand how to > correlate data from signal "handle-sync" > (http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-good-plugins/html/gst-plugins-good-plugins-gstrtpjitterbuffer.html#GstRtpJitterBuffer-handle-sync) > of GstRtpJitterBuffer and "stats" of rtpsession but I really don't > understand what base-time is.... > > This is what I get from GstRtpJitterBuffer "handle-sync" signal: > > application/x-rtp-sync, base-rtptime=(guint64)2490599386, > base-time=(guint64)137714729, clock-rate=(uint)90000, > sr-ext-rtptime=(guint64)2491725922, > sr-buffer=(buffer)80c800069af6cadbd39457a5e959817b9484b862000003ed0010b1da81ca000c9af6cadb0116726f6f7440616f63632d617869732d646f6d656f6c640204726f6f7406094753747265616d6572000000; > > and at the same time from rtpsource "stats": > > application/x-rtp-source-stats, ssrc=(uint)2599865051, > internal=(boolean)false, validated=(boolean)true, > received-bye=(boolean)false, is-csrc=(boolean)false, > is-sender=(boolean)true, seqnum-base=(int)-1, clock-rate=(int)90000, > rtp-from=(string)192.168.3.27:50088, > rtcp-from=(string)192.168.3.27:50089, octets-sent=(guint64)0, > packets-sent=(guint64)0, octets-received=(guint64)1155650, > packets-received=(guint64)1060, bitrate=(guint64)703428, > packets-lost=(int)0, jitter=(uint)83, have-sr=(boolean)true, > sr-ntptime=(guint64)15245907008652149115, sr-rtptime=(uint)2491725922, > sr-octet-count=(uint)1094106, sr-packet-count=(uint)1005, > sent-rb=(boolean)true, sent-rb-fractionlost=(uint)0, > sent-rb-packetslost=(int)0, sent-rb-exthighestseq=(uint)18120, > sent-rb-jitter=(uint)97, sent-rb-lsr=(uint)1470108312, > sent-rb-dlsr=(uint)337017, have-rb=(boolean)false, > rb-fractionlost=(uint)0, rb-packetslost=(int)0, > rb-exthighestseq=(uint)0, rb-jitter=(uint)0, rb-lsr=(uint)0, > rb-dlsr=(uint)0, rb-round-trip=(uint)0; > > Does anybody know how to obtain the damn time reference from > sr-rtptime/sr-ntptime to pipeline "absolute time" (aka the one > defined here http://cgit.freedesktop.org/gstreamer/gstreamer/tree/docs/design/part-synchronisation.txt)? > > TIA, > > pz > > > > > 2012/6/26 Pazzo Da Legare <[hidden email]>: >> Dear Josh, >> >> Thank you very much for your links. >> >> I thought I couldn't find the right parameter to instruct rtspsrc to >> propagate the time downstream (or better to say to use the rtsp source >> time as clock reference) I was more than sure that it would have been >> possible, but now you confirm that a "crazy" idea to manage sr-message >> is the only (known) way to extract source reference: I'm trying to >> follow exactly the same approach trying to extract absolute time from >> rtspsrc and send a metadata event (GST_EVENT_TAG) through my pipeline. >> The point is how to correlate internal absolute time (what you can get >> with gst_clock_get_time()) and ntptime of RTCP protocol without >> _error_ (i.e. taking into account source->rtspsrc transmission time)? >> >> I can intercept RtpSession information but I have no way to relate >> (sr-ntptime, sr-rtptime) with the time (internal absolute time) of the >> frame they are referring to. Any clue? >> >> BR, >> pz >> >> >> >> >> 2012/6/26 Josh Doe <[hidden email]>: >>> On Tue, Jun 26, 2012 at 6:06 AM, Pazzo Da Legare >>> <[hidden email]> wrote: >>>> Dear all, >>>> >>>> How can I convert gst_clock_get_time() value in an absolute time (with >>>> year, month, day, ....). I'm playing with an rtsp camera, using >>>> rtspsrc, and I would like to retrieve absolute time (ntp stream time) >>>> across my pipeline. Is there an easy way to do that? >>>> >>>> from element's clock time now (=Tue Jun 26 12:03:34 CEST 2012) I get >>>> something like: >>>> >>>> 6112256969101111 >>>> >>>> and it contains a bunch of thousands of seconds.... >>>> >>>> I'm a little bit puzzled. >>> >>> gst_clock_get_time() will just give you a monotonically increasing >>> integer. Subtracting the base time from that will give you the stream >>> time: >>> http://gstreamer.freedesktop.org/data/doc/gstreamer/head/manual/html/chapter-clocks.html >>> >>> If you're talking about the ISO 8601 timestamps that indicate the >>> absolute UTC time, this doesn't appear to be implemented currently: >>> http://cgit.freedesktop.org/gstreamer/gst-plugins-base/tree/gst-libs/gst/rtsp/gstrtsprange.c#n249 >>> http://tools.ietf.org/html/rfc2326#page-18 >>> >>> A few issues. Not all servers support absolute time ranges. You can >>> only get an absolute time if you requested the range in the same >>> format, so rtspsrc would need to be given this information. Or you >>> could extract a time range from SDP. Either way, you'd need a way to >>> get the time to the application. >>> >>> This last part is what I'm interested. For now I'm sending a >>> GST_TAG_DATE_TIME event to indicate the start time of the stream, so a >>> buffer absolute time can be calculated from this absolute time and the >>> stream time. If there's a better way (GstMeta?) then I'd like to hear >>> it. >>> >>> -Josh >>> _______________________________________________ >>> gstreamer-devel mailing list >>> [hidden email] >>> http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel gstreamer-devel mailing list [hidden email] http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
Re: gstclock and absolute time
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Hi all,
Another update. Using this pipeline GST_DEBUG=rtpbin:5 gst-launch --gst-debug-no-color rtspsrc location=rtsp://192.168.3.27/axis-media/media.amp?audio=0 latency=200 ! rtph264depay ! ffdec_h264 ! ffmpegcolorspace ! fakesink (the log is http://pastebin.com/iYUpyCZR) I have no more asserts. Anyone can figure out why? Why my UNIX local time from 0? Is there a way to propagate across the pipeline the _remote time_, with events or using buffer timestamp? TIA, pz- 2012/6/26 Pazzo Da Legare <[hidden email]>: > Hi all again, > > Probably I found something interesting activating log for "rtpbin": > > GST_DEBUG=rtpbin:5 gst-launch --gst-debug-no-color rtspsrc > location=rtsp://192.168.3.27/axis-media/media.amp?audio=0 latency=200 > ! rtph264depay ! ffdec_h264 ! ffmpegcolorspace ! shmframeserver > latency=200 ! ffmpegcolorspace ! fakesink > > > http://pastebin.com/ZqaN09MQ > > it seems that rtpbin cannot read localtime....any clue? Is it a bug? > > BR, > > pz > > 2012/6/26 Pazzo Da Legare <[hidden email]>: >> Dear Josh, >> >> I want just to add a bit of info. I'm trying to understand how to >> correlate data from signal "handle-sync" >> (http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-good-plugins/html/gst-plugins-good-plugins-gstrtpjitterbuffer.html#GstRtpJitterBuffer-handle-sync) >> of GstRtpJitterBuffer and "stats" of rtpsession but I really don't >> understand what base-time is.... >> >> This is what I get from GstRtpJitterBuffer "handle-sync" signal: >> >> application/x-rtp-sync, base-rtptime=(guint64)2490599386, >> base-time=(guint64)137714729, clock-rate=(uint)90000, >> sr-ext-rtptime=(guint64)2491725922, >> sr-buffer=(buffer)80c800069af6cadbd39457a5e959817b9484b862000003ed0010b1da81ca000c9af6cadb0116726f6f7440616f63632d617869732d646f6d656f6c640204726f6f7406094753747265616d6572000000; >> >> and at the same time from rtpsource "stats": >> >> application/x-rtp-source-stats, ssrc=(uint)2599865051, >> internal=(boolean)false, validated=(boolean)true, >> received-bye=(boolean)false, is-csrc=(boolean)false, >> is-sender=(boolean)true, seqnum-base=(int)-1, clock-rate=(int)90000, >> rtp-from=(string)192.168.3.27:50088, >> rtcp-from=(string)192.168.3.27:50089, octets-sent=(guint64)0, >> packets-sent=(guint64)0, octets-received=(guint64)1155650, >> packets-received=(guint64)1060, bitrate=(guint64)703428, >> packets-lost=(int)0, jitter=(uint)83, have-sr=(boolean)true, >> sr-ntptime=(guint64)15245907008652149115, sr-rtptime=(uint)2491725922, >> sr-octet-count=(uint)1094106, sr-packet-count=(uint)1005, >> sent-rb=(boolean)true, sent-rb-fractionlost=(uint)0, >> sent-rb-packetslost=(int)0, sent-rb-exthighestseq=(uint)18120, >> sent-rb-jitter=(uint)97, sent-rb-lsr=(uint)1470108312, >> sent-rb-dlsr=(uint)337017, have-rb=(boolean)false, >> rb-fractionlost=(uint)0, rb-packetslost=(int)0, >> rb-exthighestseq=(uint)0, rb-jitter=(uint)0, rb-lsr=(uint)0, >> rb-dlsr=(uint)0, rb-round-trip=(uint)0; >> >> Does anybody know how to obtain the damn time reference from >> sr-rtptime/sr-ntptime to pipeline "absolute time" (aka the one >> defined here http://cgit.freedesktop.org/gstreamer/gstreamer/tree/docs/design/part-synchronisation.txt)? >> >> TIA, >> >> pz >> >> >> >> >> 2012/6/26 Pazzo Da Legare <[hidden email]>: >>> Dear Josh, >>> >>> Thank you very much for your links. >>> >>> I thought I couldn't find the right parameter to instruct rtspsrc to >>> propagate the time downstream (or better to say to use the rtsp source >>> time as clock reference) I was more than sure that it would have been >>> possible, but now you confirm that a "crazy" idea to manage sr-message >>> is the only (known) way to extract source reference: I'm trying to >>> follow exactly the same approach trying to extract absolute time from >>> rtspsrc and send a metadata event (GST_EVENT_TAG) through my pipeline. >>> The point is how to correlate internal absolute time (what you can get >>> with gst_clock_get_time()) and ntptime of RTCP protocol without >>> _error_ (i.e. taking into account source->rtspsrc transmission time)? >>> >>> I can intercept RtpSession information but I have no way to relate >>> (sr-ntptime, sr-rtptime) with the time (internal absolute time) of the >>> frame they are referring to. Any clue? >>> >>> BR, >>> pz >>> >>> >>> >>> >>> 2012/6/26 Josh Doe <[hidden email]>: >>>> On Tue, Jun 26, 2012 at 6:06 AM, Pazzo Da Legare >>>> <[hidden email]> wrote: >>>>> Dear all, >>>>> >>>>> How can I convert gst_clock_get_time() value in an absolute time (with >>>>> year, month, day, ....). I'm playing with an rtsp camera, using >>>>> rtspsrc, and I would like to retrieve absolute time (ntp stream time) >>>>> across my pipeline. Is there an easy way to do that? >>>>> >>>>> from element's clock time now (=Tue Jun 26 12:03:34 CEST 2012) I get >>>>> something like: >>>>> >>>>> 6112256969101111 >>>>> >>>>> and it contains a bunch of thousands of seconds.... >>>>> >>>>> I'm a little bit puzzled. >>>> >>>> gst_clock_get_time() will just give you a monotonically increasing >>>> integer. Subtracting the base time from that will give you the stream >>>> time: >>>> http://gstreamer.freedesktop.org/data/doc/gstreamer/head/manual/html/chapter-clocks.html >>>> >>>> If you're talking about the ISO 8601 timestamps that indicate the >>>> absolute UTC time, this doesn't appear to be implemented currently: >>>> http://cgit.freedesktop.org/gstreamer/gst-plugins-base/tree/gst-libs/gst/rtsp/gstrtsprange.c#n249 >>>> http://tools.ietf.org/html/rfc2326#page-18 >>>> >>>> A few issues. Not all servers support absolute time ranges. You can >>>> only get an absolute time if you requested the range in the same >>>> format, so rtspsrc would need to be given this information. Or you >>>> could extract a time range from SDP. Either way, you'd need a way to >>>> get the time to the application. >>>> >>>> This last part is what I'm interested. For now I'm sending a >>>> GST_TAG_DATE_TIME event to indicate the start time of the stream, so a >>>> buffer absolute time can be calculated from this absolute time and the >>>> stream time. If there's a better way (GstMeta?) then I'd like to hear >>>> it. >>>> >>>> -Josh >>>> _______________________________________________ >>>> gstreamer-devel mailing list >>>> [hidden email] >>>> http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel gstreamer-devel mailing list [hidden email] http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
Re: gstclock and absolute time
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In reply to this post by Josh Doe
Dear Josh,
wtay_ of #gstreamer IRC , author of rtpbin, confirm me that the only way to get reference between pipeline time and rtsp source rtp time is to modify rtpbin plugin to add a property, a signal or an event.... pz 2012/6/26 Josh Doe <[hidden email]>: > On Tue, Jun 26, 2012 at 6:06 AM, Pazzo Da Legare > <[hidden email]> wrote: >> Dear all, >> >> How can I convert gst_clock_get_time() value in an absolute time (with >> year, month, day, ....). I'm playing with an rtsp camera, using >> rtspsrc, and I would like to retrieve absolute time (ntp stream time) >> across my pipeline. Is there an easy way to do that? >> >> from element's clock time now (=Tue Jun 26 12:03:34 CEST 2012) I get >> something like: >> >> 6112256969101111 >> >> and it contains a bunch of thousands of seconds.... >> >> I'm a little bit puzzled. > > gst_clock_get_time() will just give you a monotonically increasing > integer. Subtracting the base time from that will give you the stream > time: > http://gstreamer.freedesktop.org/data/doc/gstreamer/head/manual/html/chapter-clocks.html > > If you're talking about the ISO 8601 timestamps that indicate the > absolute UTC time, this doesn't appear to be implemented currently: > http://cgit.freedesktop.org/gstreamer/gst-plugins-base/tree/gst-libs/gst/rtsp/gstrtsprange.c#n249 > http://tools.ietf.org/html/rfc2326#page-18 > > A few issues. Not all servers support absolute time ranges. You can > only get an absolute time if you requested the range in the same > format, so rtspsrc would need to be given this information. Or you > could extract a time range from SDP. Either way, you'd need a way to > get the time to the application. > > This last part is what I'm interested. For now I'm sending a > GST_TAG_DATE_TIME event to indicate the start time of the stream, so a > buffer absolute time can be calculated from this absolute time and the > stream time. If there's a better way (GstMeta?) then I'd like to hear > it. > > -Josh > _______________________________________________ > gstreamer-devel mailing list > [hidden email] > http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel gstreamer-devel mailing list [hidden email] http://lists.freedesktop.org/mailman/listinfo/gstreamer-devel |
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