NTP timestamps

Accelerated Computing Intelligent Video Analytics DeepStream SDK
1

• Hardware Platform = Jetson Orin NX
• DeepStream Version = 6.3
• JetPack Version = 5.1.4
• TensorRT Version = 8.5.2.2
• NVIDIA GPU Driver Version = 11.4.315
• Issue Type = questions

When I used deeepstream-test-app-c my_config.txt to reason about my local mp4 video, a warning appeared:

WARNING;  playback mode used with URI [file:///home/nvidia/…DJI_20250826114229_0003_S.MP4] not conforming to timestamp format;  check README;  using system-time

**PERF: 68.70 (68.62) 
** WARN: <bbox_generated_probe_after_analytics:615>: Source 0: NTP timestamps are backward in time. Current: 1758349638017845000 previous: 1758349638972147000 
** WARN: <bbox_generated_probe_after_analytics:615>: Source 0: NTP timestamps are backward in time. Current: 1758349639016239000 previous: 1758349639975548000 
** WARN: <bbox_generated_probe_after_analytics:615>: Source 0: NTP timestamps are backward in time. Current: 1758349640013040000 previous: 1758349640957960000 
** WARN: <bbox_generated_probe_after_analytics:615>: Source 0: NTP timestamps are backward in time. Current: 1758349641003044000 previous: 1758349641958636000 
** WARN: <bbox_generated_probe_after_analytics:615>: Source 0: NTP timestamps are backward in time. Current: 1758349642002013000 previous: 1758349642947039000

I checked my code again and found that if I use deepstream-app-c my_config.txt, it won’t prompt the above warning. But if I use deepstream-test5-app-c my_config.txt, it will show above warning. I set attach-sys-ts-as-ntp=1 up, no warning appeared.

I wonder if this will affect the detection and tracking results? How can this warning be eliminated? Because I reasoned the same video on another Orin NX development board, such a warning would not occur.

Looking forward to your help. Thank you!

6

Because this log only exists in deepstream_test5_app_main.c, but not in deepstream_app.c

It will not affect the detection/tracking results. In addition, these logs are only valid when rtsp and rtcp-sr packets are received or local file name as *__M_DD_YYYY_H_MIN_SEC_MSEC_AM/PM_UTC<Offset>.mp4.

You can find the following content in README.

 6.1 -p 0 (PLAYBACK=0)
  (Base UTC timestamp for meta-data from RTCP SR for RTSP Sources
              only; any sources other than type=4 will default to PLAYBACK=1)
  $ ./deepstream-test5-app -c test5_dec_infer-resnet_tracker_sgie_tiled_display_int8.txt -p 0
  ==============================================================================
  NOTE 1: For RTSP Streams, Config file shall use 'type=4'(NV_DS_SOURCE_RTSP)
  in [source] groups
  ==============================================================================
  NOTE 2: If the RTSP Camera/Server does not send RTCP Sender Report - or until
  the first Sender Report arrive, the buffer/metadata timestamps sent out by
  nvmsgbroker will be based on the initial timestamp as zero.
  ==============================================================================

  6.2 -p 1 (PLAYBACK=1)
  (Base UTC timestamp from filename of format - *__M_DD_YYYY_H_MIN_SEC_MSEC_AM/PM_UTC<Offset>.mp4)
  Means - the first video frame timestamp is embedded in the URI.
  Example: VideoFileSavedFromCamera__4_11_2018_4_59_59_433_AM_UTC-07_00.mp4
  $ ./deepstream-test5-app -c test5_dec_infer-resnet_tracker_sgie_tiled_display_int8.txt -p 1
  =============================================================================
  NOTE: If URI does not have original timestamp embedded, a WARNING will be
  thrown to user and current system time will be used as base time for all metadata
  ==============================================================================
7

Thanks for your help!