The Accuware Sentinel CSV service is a service that logs the locations of all the people seen by each camera of your site producing a CSV file every 5 minutes. The service might be subject to changes and interruptions due to maintenance and upgrades. Notifications of possible changes or interruptions in case of updates are provided well in advance.

Data structure

Data inside the CSV files are ordered by time-stamp and frame number. The order of the fields shown below can be subjected to changes. So, please build your script/parser without assuming the fact that the grouping and the order of the fields described below will be like this forever. Anyway notifications in case of changes are provided well in advance.

Where the fields are:

  • Column 1 – Timestamp – UNIX Epoch time stamp in milliseconds (see the info box below for details). Alternatively we can provide the number of milliseconds elapsed since the beginning of the video.
  • Column 2 – Frame number – every frame in a video stream is assigned a consecutive number. The frame number is shown inside the lower left corner of the processed video.
  • Column 3 – Person ID – this is an auto-generated number that identifies each pedestrian on the video. More information about this can be found inside this page.
  • Column 4 – Position X – this is the absolute position of the feet in screen coordinates (pixels).
  • Column 5 – Position Y – this is the absolute position of the feet in screen coordinates (pixels).
  • Columns 6 to 9 – represents the location in pixels of the tracking box (x, y, width, height).
  • Column 10 – used internally by Accuware for debug purposes.

Unix epoch timestamp: the Unix epoch (or Unix time or POSIX time or Unix timestamp) is the number of seconds that have elapsed since January 1, 1970 (midnight UTC/GMT), not counting leap seconds (in ISO 8601: 1970-01-01T00:00:00Z):

  • More information about the Unix epoch timestamp can be found in this page
  • More information about how to convert epoch to human readable date and vice versa can be found in this page

Alternative positions

At a later stage we will make available a graphic tool inside the Accuware dashboard that allows you to calibrate the view of the camera against a floor plan using a calibration grid. Doing so it will be possible to retrieve the positions (fields 4 and 5):

  • as distance in meters of the person’s feet from the origin of the calibration grid.
  • or as GPS coordinates (a pair of latitude and longitude).

The calibration will be a relatively simple process that won’t take more than 5 minutes per camera. The one below is an example of calibration grid. At present we are setting the calibration grid manually. In the image below, the origin of the grid (0,0) is the point in the bottom left corner. Based on the calibration grid it is easy to select region of interest on the floor. For example:

  • if you want to analyze the number of people that are walking in the right side of the aisle, you have to consider all the rows of the CSV file with Position X >= 1.25 meters.
  • if you want to analyze the number of people detected on the blue tile, you have to consider all the rows of the CSV file with 2.0 < Position X < 2.5 and  0 < Position Y < 0.5 (each square in the grid is 0.5 x 0.5 meters).

video_tracker_calibration_grid

Download

The CSV files can be downloaded using the Accuware Sentinel dashboard or by calling an URL with the following structure:

Where:

  • Host: is the IP of the localhost (for local installations) or this URL s3.amazonaws.com/accuware.cv.sites (for cloud installations)
  • SiteID: is the ID of your site (provided by the Accuware Technical Support)
  • CameraID: is the ID of your camera (provided by the Accuware Technical Support)
  • YYYY: for digits for the year
  • MM: two digits for and the month
  • DD: two digits for the day
  • HH: two digits for the hour
  • mm: two digits for the minutes

Availability

CSV files are generated every 5 minutes but there is approximately a 10 minute delay. So if it’s 12.30 PM, the time table will show data collected until 12.20 PM.

Retention

Currently, the retention of the CSV files is unlimited. Anyway, since this might change in the near future, we suggest to download the CSV files on a regular base using a simple script, and store them in your local repository

Index file for each day

Each CSV file contains data for a time window of 5-minutes. In addition to these CSV files we provide also an index file with a list of all the 5-minutes segments recorded in a day. This index file can be downloaded by calling an URL with the following structure:

Where:

  • Host: is the IP of the localhost (for local installations) or this URL s3.amazonaws.com/accuware.cv.sites (for cloud installations)
  • SiteID: is the ID of your site (provided by the Accuware Technical Support)
  • CameraID: is the ID of your camera (provided by the Accuware Technical Support)
  • YYYY: for digits for the year
  • MM: two digits for and the month
  • DD: two digits for the day

The JSON returned will look like this:

Where the fields are:

  1. time – the identifier of the segment.
  2. video_in  – the file name of the original video.
  3. video_out – the file name of the processed video.
  4. detection_count – the total number of people detected inside the segment.
  5. frame_start – the starting frame of the segment.
  6. frame_end – the ending frame of the segment.