Can a Pelco or 3rd party IP camera record using timelapse (1 frame every 60 seconds) on a Digital Sentry video recorder?

Issue

Would like to record a construction project for a 1 year period using time-lapse recording, set for 1 frame every 60 seconds, but Digital Sentry records a minimum of 1 image per second.

Product Line

Pelco Cameras, Pelco Video Management

Environment

  • Digital Sentry version 7.1.47 and above
  • DSSRV
  • DS NVs
  • DS ControlPoint
  • Pelco IP cameras
    • Used for article - Sarix IMP519
    • Sarix first generation/Enhanced = I-frame Interval
    • Sarix Professional = GOP Length

Cause

The minimum configurable frame per second when adding an IP camera to a Digital Sentry recorder is 1 frame per second.

Resolution

Yes, but this cannot be done using the native Pelco IP camera driver as the minimum configuration is 1FPS.

To work around the 1 frame per second limitation we need to use the "Storage Rate" feature in DS Admin.  To understand how this feature works with IP cameras (h.264 and mpeg4 | LOW = records only every other i-Frame and MEDIUM = records only every i-Frame), refer to article: Does the bump on alarm work for IP cameras in Digital Sentry?

The general idea is when the camera is configured to stream video at 1 frame per second, we need the i-Frame interval (or GOP Length) in the camera to = 60 (if wanting 1 frame every 60 seconds, this setting could be extended for more of a time-lapse effect).

We cannot use the native Pelco driver because it hard sets the i-Frame interval / GOP Length to = 2 i-Frames every second.  This means that if we use the MEDIUM or LOW storage rate settings in DS Admin, we would record 2FPS for MEDIUM and 1FPS for SLOW.
To get around this we need to use another driver to communicate and request the video stream from the camera, we can use either the ONVIF or OTHER (RTSP URL) drivers.  These will not override the i-Frame interval / GOP Length configured in the video stream of the cameras web interface.

Limitations: The amount of time-lapse between recorded frames is completely dependant on the allowed I-Frame interval configuration in the IP camera.  For example, a Sarix Professional series camera will allow a GOP Length between 1 - 100 at 1ips, where a Sarix Enhanced or Sarix first generation will only allow a I-Frame interval of 1 - 8.  This means that a Sarix Pro can do 1 image every 100 seconds maximum and a Sarix Enhanced or Sarix first gen can do 1 image every 8 seconds max.

  • Sarix Pro = 1 image every 100 seconds maximum (depending on image rate and resolution configuration)
  • Sarix Enhanced or first gen = 1 image every 8 seconds maximum


 

  1. Add the IP camera to a Digital Sentry recorder:
  2. Connect to the cameras web interface and set the Compression Standard to H264 and Image Rate of the stream to 1 image per second.
     
  3. Set the GOP Length / I-Frame Interval to the number of seconds you would like the recording to be...i.e. if you want 1 image per minute, set the interval to 60.

    Sarix Pro example:


     
  4. Open DS Admin and click on the camera under the Cameras folder.
     
  5. Select the "Time-lapse Storage" tab.
     
  6. In the Storage Rate section, click on the Black square "Medium" and then click the "Full Week Medium" button. 


     
  7. Make sure to Save before exiting DS Admin.  Also verify there are no schedules configured in the Event Storage tab.

 

In the DS ControlPoint client software,  live video should be 1 image per second and playback video will be 1 image every 60 seconds.  Playback video will seem to playback in fast forward.  If you use the Forward Step option on the playback controls you will see the amount of time between frames.