Nvarguscamerasrc timestamping

[user27558]

Hello,
I am running Jetpack 4.6 and L4T 32.6.1.

I am using gstreamer and the nvarguscamerasrc plugin to create a stream and I would like to get absolute timestamps in my gstreamer pipeline. But the PTS timestamp doesn’t make sense.
Here’s how I test it :

gst-launch-1.0 -v nvarguscamerasrc sensor-id=0 ! fakesink silent=false

Here’s the output :

Setting pipeline to PAUSED ...
Pipeline is live and does not need PREROLL ...
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = event   ******* (fakesink0:sink) E (type: stream-start (10254), GstEventStreamStart, stream-id=(string)a37df85956a2cf47c52a834621cb9809, flags=(GstStreamFlags)GST_STREAM_FLAG_NONE, group-id=(uint)1;) 0x55b48bd5d0
Setting pipeline to PLAYING ...
New clock: GstSystemClock
/GstPipeline:pipeline0/GstNvArgusCameraSrc:nvarguscamerasrc0.GstPad:src: caps = video/x-raw(memory:NVMM), width=(int)1920, height=(int)1080, format=(string)NV12, framerate=(fraction)30/1
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = event   ******* (fakesink0:sink) E (type: caps (12814), GstEventCaps, caps=(GstCaps)"video/x-raw\(memory:NVMM\)\,\ width\=\(int\)1920\,\ height\=\(int\)1080\,\ format\=\(string\)NV12\,\ framerate\=\(fraction\)30/1";) 0x55b48bd640
/GstPipeline:pipeline0/GstFakeSink:fakesink0.GstPad:sink: caps = video/x-raw(memory:NVMM), width=(int)1920, height=(int)1080, format=(string)NV12, framerate=(fraction)30/1
GST_ARGUS: Creating output stream
CONSUMER: Waiting until producer is connected...
GST_ARGUS: Available Sensor modes :
GST_ARGUS: 1920 x 1080 FR = 29,999999 fps Duration = 33333334 ; Analog Gain range min 1,000000, max 31,622776; Exposure Range min 59000, max 33333000;

GST_ARGUS: Running with following settings:
   Camera index = 0 
   Camera mode  = 0 
   Output Stream W = 1920 H = 1080 
   seconds to Run    = 0 
   Frame Rate = 29,999999 
GST_ARGUS: Setup Complete, Starting captures for 0 seconds
GST_ARGUS: Starting repeat capture requests.
CONSUMER: Producer has connected; continuing.
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = event   ******* (fakesink0:sink) E (type: segment (17934), GstEventSegment, segment=(GstSegment)"GstSegment, flags=(GstSegmentFlags)GST_SEGMENT_FLAG_NONE, rate=(double)1, applied-rate=(double)1, format=(GstFormat)GST_FORMAT_TIME, base=(guint64)0, offset=(guint64)0, start=(guint64)0, stop=(guint64)18446744073709551615, time=(guint64)0, position=(guint64)0, duration=(guint64)18446744073709551615;";) 0x55b48bd6b0
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = preroll   ******* 
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain   ******* (fakesink0:sink) (1008 bytes, dts: 0:00:01.665492543, pts: 0:00:01.665492543, duration: none, offset: -1, offset_end: -1, flags: 00000040 discont , meta: none) 0x7f7800a080
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain   ******* (fakesink0:sink) (1008 bytes, dts: 0:00:01.696078377, pts: 0:00:01.696078377, duration: none, offset: -1, offset_end: -1, flags: 00000000 , meta: none) 0x7f7800a190
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain   ******* (fakesink0:sink) (1008 bytes, dts: 0:00:01.729442996, pts: 0:00:01.729442996, duration: none, offset: -1, offset_end: -1, flags: 00000000 , meta: none) 0x7f7800a2a0
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain   ******* (fakesink0:sink) (1008 bytes, dts: 0:00:01.762407295, pts: 0:00:01.762407295, duration: none, offset: -1, offset_end: -1, flags: 00000000 , meta: none) 0x7f7800a3b0
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain   ******* (fakesink0:sink) (1008 bytes, dts: 0:00:01.795593962, pts: 0:00:01.795593962, duration: none, offset: -1, offset_end: -1, flags: 00000000 , meta: none) 0x7f7800a4c0
/GstPipeline:pipeline0/GstFakeSink:fakesink0: last-message = chain   ******* (fakesink0:sink) (1008 bytes, dts: 0:00:01.828735989, pts: 0:00:01.828735989, duration: none, offset: -1, offset_end: -1, flags: 00000000 , meta: none) 0x7f7800a5d0
[...]

I understood that the pts timestamp should contain the absolute timestamp at which the frame was captured, but here it starts at zero. Is it normal ?
If so, how can I get the absolute timestamp ?

Thanks for your help !

[ShaneCCC]

I would suggest to use Argus API to get the timestamp. Have a check the following topic.

Argus::ICaptureMetadata::getSensorTimestamp clock domain in L4T 32.4.4

hello Denisss, since you’re now working with l4r-r32.4.4. please note that there’ll be timestamp modification for next public release. please refer to the statement in Topic 78821, recap as below… we had some changes for Xavier to plumbed up the hardware timestamps into camera software stack. there’ll be start-of-frame and end-of-frame sensor timestamps include in metadata from TSC hardware, by using new interfaces for TSC HW timestamp; you may expect those changes will be include to next p…

[user27558]

Thanks for your answer. Is there any documentation for this functionality ?
Also, is it the only way to get the timestamp ? It’s not possible to get it through gstreamer ?

Thanks !

[ShaneCCC]

Check below document. And you can get the nvarguscamerasrc source code to implement for your case.

https://docs.nvidia.com/jetson/l4t-multimedia/classArgus_1_1ICaptureMetadata.html#ae4ff79489b0aef6766742a61d1a17cfc