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      Object Detection - Product Formats

      Object Detection Product Format 

      This page describes the format of several object detection analytic results that are delivered to Ursa customers. The product consists of a single vector product file (GeoJSON) that describes each detected object. Some products may also include raster products (GeoTIFF) representing  chips of each detected object. 

      1. GeoJSON File 
      2. Features 
      3. SAR Properties 
      4. AIS Properties 
      5. Ship-to-Ship Transfer Properties 
      6. RF Properties 
      7. Change Detection Properties 
      8. Classification Properties 
      9. Analytics <> Fields Mapping 

      GeoJSON File 

      The GeoJSON file is stored as a standard Ursa Analytic GeoJSON Product, with the following additional requirements. 

      Features 

      The properties object consists of the following fields: 

      Field Name 

      Type 

      Description

      uuid 

      string 

      Unique detection identifier.

      geometrySource 

      string 

      Source of geo-location and target information used to define this feature’s Polygon  vertices.

      detectionNumber 

      int 

      Detection number.

      label 

      string 

      Optional label associated with the change.

      area 

      number 

      Optional polygon area in square meters.

      sar* 

      		  

      Fields related to SAR-based object detection, described in the SAR Properties  table below.

      ais* 

      		  

      Fields related to AIS metadata, described in the AIS Properties table below.

      sts* 

      		  

      Fields related to identification of a potential ship-to-ship transfer, described in the  Ship-to-Ship Transfer Properties table below.

      rf* 

      		  

      Fields related to RF detections associated with the object.

      change* 

      		  

      Field related to change detection processing.

      classification* 

      		  

      Fields that describe the most likely classification of the object, described in the  Classification Properties table below.

      classificationDetails 

      list 

      List of Classification objects, one for each of the N most likely target  classifications. Each object is a dictionary with the fields described in the  Classification Properties table below.


      SAR Properties 

      The SAR properties that were extracted via SAR-based signal processing are described in the table below.

      Field Name 

      Type 

      Description

      sarLatitude 

      number 

      Latitude of the centroid of the object, as detected in the SAR imagery.

      sarLongitude 

      number 

      Longitude of the centroid of the object, as detected in the SAR imagery.

      sarLength 

      number 

      Length of the object, in meters, as detected in the SAR imagery.

      sarWidth 

      number 

      Width of the object, in meters, as detected in the SAR imagery.

      sarHeading 

      number 

      Heading of the object, in degrees clockwise from true north, as detected in the  SAR imagery.

      sarDetectionTimeUTC 

      string 

      Date and time of the detection, described in ISO 860 format using the following  format: 

      YYYY-MM-DDThh:mm:ss.sssZ 

      e.g. ‘2022-02-04T18:15:05.089Z’

      sarDetectionConfidence 

      number 

      Confidence that the detected object is an object of interest, on a scale of 0 to 1.

      sarChipIdentifier 

      string 

      UUID string containing chip identifier.

      sarImageIndex 

      number 

      Reference to the image in the GeoJSON sensorData list in which this target was  detected. This will line up with the image's sensorDataIndex field

      AIS Properties 

      The AIS properties that were extracted via AIS metadata are described in the table below.

      Field Name 

      Type 

      Description

      aisCorrelationConfidence 

      number 

      Confidence that the detected object is associated with a specific AIS record, on a  scale of 0 to 1.

      aisMmsi 

      string 

      MMSI number (Maritime Mobile Service Identity), a unique nine-digit number for  ship identification. Sourced from associated AIS records.

      aisImo 

      string 

      IMO (International Maritime Organization)-assigned unique reference number.  Sourced from associated AIS records.

      aisPredictionTimeUTC 

      string 

      Time associated with the position and velocity information provided in this record,  described in ISO 860 format using the following format: 

      YYYY-MM-DDThh:mm:ss.sssZ 

      e.g. ‘2022-02-04T18:15:05.089Z’

      aisLatitude 

      number 

      Coasted vessel latitude, in degrees.

      aisLongitude 

      number 

      Coasted vessel longitude, in degrees.

      aisSpeed 

      number 

      Vessel’s speed, in meters/second.

      aisCourse 

      number 

      Vessel’s course, in degrees clockwise from true north.

      aisHeading 

      number 

      Vessel’s heading, in degrees clockwise from true north.

      aisLength 

      number 

      Vessel’s length, in meters.

      aisWidth 

      number 

      Vessel’s width, in meters.

      aisName 

      string 

      Vessel’s name.

      aisFlag 

      string 

      Vessel’s country of origin/flag.

      aisShipType 

      string 

      Vessel’s ship type.

      aisShipClass 

      string 

      Vessel’s ship class.

      aisCallsign 

      string 

      Vessel’s call sign.

      aisDraught 

      number 

      Vessel’s draught, in meters.

      aisDestination 

      string 

      Vessel’s destination.

      aisEta 

      string 

      Time that the vessel will arrive at its destination.

      aisTrackIdBefore 

      string 

      UUID of AIS record immediately before the estimated AIS

      aisTrackIdAfter 

      string 

      UUID of AIS record immediately after the estimated AIS

      aisEstError 

      number 

      Estimated geospatial error for given prediction, in meters

      aisErrorSemimajor 

      number 

      Error ellipsoid semimajor axis length, in meters

      aisErrorSemiminor 

      number 

      Error ellipsoid semiminor axis length, in meters

      aisErrorOrientation 

      number 

      Error ellipsoid orientation, in degrees clockwise from true north

      aisPredictionAlgorithm 

      string 

      Algorithm/method used to perform this estimation

      aisPredictionConfidence 

      number 

      Confidence associated with this estimate from 0 to 1

      Ship-to-Ship Transfer Properties 

      Field Name 

      Type 

      Description

      stsProbability 

      number 

      Likelihood of the ship actively performing a ship-to-ship transfer, on a scale  of 0 to 1

      stsSecondMmsi 

      string 

      The MMSI of the other vessel performing a ship-to-ship transfer with this  vessel

      stsSecondClass 

      string 

      The vessel type (class) of the other vessel performing a ship-to-ship transfer  with this vessel

      stsTransferType 

      string 

      The type of ship-to-ship transfer being performed (discrete options to be  determined throughout development of the algorithm)

      RF Properties

      Field Name 

      Type 

      Description

      rfDataIndex 

      int 

      Reference to source data file in the sensorData section of the product.

      rfLatitude 

      number 

      Latitude of the centroid of the object, as detected in the RF data.

      rfLongitude 

      number 

      Latitude of the centroid of the object, as detected in the RF data.

      rfDetectionTimeUTC 

      string 

      Collection start time, described in ISO 8601 format using the following  format: 

      YYYY-MM-DDThh:mm:ss.ffffff

      rfDetectionConfidence 

      number 

      Confidence in the presence of an RF emitter, on a scale of 0 to 1.

      rfGeolocationErrorSemiMajorAxis 

      number 

      Geolocation error ellipse’s semi-major axis length, in meters. This field  is optional and will not be included in exported products.

      rfGeolocationErrorSemiMinorAxis 

      number 

      Geolocation error ellipse’s semi-minor axis length, in meters. This field  is optional and will not be included in exported products.

      rfGeolocationErrorOrientation 

      number 

      Geolocation error ellipse’s orientation, in degrees clockwise with  respect to true north. This field is optional and will not be included in  exported products.

      rfCenterFrequencyHz 

      number 

      Detection center frequency, in Hz

      rfSignalBandwidthHz 

      number 

      Detection bandwidth, in Hz

      rfSignalType 

      string 

      RF signal type of the detected emitter. Options include: 

      • AIS 
      • Cellular Base Station 
      • GPS Jammer 
      • Pulsed Radar

      rfChannel 

      string 

      The RF channel on which a signal is detected. Interpretation is  dependent on band and signal type.

      rfModulationScheme 

      string 

      RF signal’s modulation scheme. Options include: 

      • BPSK 
      • QAM 
      • OFDM 
      • CDMA 
      • LFM

      rfReceivedPower 

      number 

      RF received power level at the sensor, in dBm.

      rfMmsi 

      string 

      Maritime Mobile Service Identity (MMSI). A unique 9 digit number that  identifies the specific vessel when the signal type is AIS

      rfMmsiConfidence 

      number 

      Confidence in the value of the MMSI, on a scale of 0 to 1

      rfNumberOfBursts 

      number 

      Number of bursts detected.

      rfMaxBursts 

      number 

      Max number of bursts detected.

      rfPulseRepetitionFrequency 

      number 

      Pulse repetition frequency, in Hz. May be used when signal type is  pulsed radar.

      rfPulseLength 

      number 

      Length (in time) of detected pulse.

      Change Detection Properties 

      Field Name 

      Type 

      Description

      changeType 

      string 

      Type of change. Choices include: ‘arrival’,  ‘departure’, ‘disturbed’, ‘other’, and ‘unknown’.

      changeMetric 

      number 

      The change statistic integrated over the change  object’s area. Since the change statistic varies from  0 to 1, this change metric will always be less than  the change object’s area.

      changeReferenceDateUTC 

      string 

      Date/time of the last known pre-change image. For  basic NCD, this will coincide with the reference  image. For MT-NCD, this will be one of the images in  the stack. 

      Described in ISO 860 format using the following  format: 

      YYYY-MM-DDThh:mm:ss.sssZ 

      e.g. ‘2022-02-04T18:15:05.089Z’

      changeDetectionDateUTC 

      string 

      Date/time of the earliest known post-change image.  For basic NCD, this will coincide with the match  image. For MT-NCD, this will be one of the images in  the stack. 

      Described in ISO 860 format using the following  format: 

      YYYY-MM-DDThh:mm:ss.sssZ 

      e.g. ‘2022-02-04T18:15:05.089Z’

      Classification Properties 

      The Classification properties describe the probability that the object is a member of a certain target class. If an object is not classified down to the  granularity of the model, the fields that cannot be populated based on the classification model that was used will be filled in with a value of  ‘Unknown’.

      Field Name 

      Type 

      Description

      classificationCategory 

      string 

      Object category (e.g., vehicle)

      classificationType 

      string 

      Object type (e.g., Aircraft)

      classificationSubtype 

      string 

      Object subtype (e.g., Fixed-wing aircraft)

      classificationClass 

      string 

      Object class (e.g., Bomber)

      classificationModel 

      string 

      Object model (e.g., H-6)

      classificationProbability 

      number 

      Classification confidence, on a scale of 0 to 1.

      Analytics <> Fields Mapping 

      The following table reflects which attributes are found within the object detection geojson output files for each of our analytics.

       

      Attribute Name 

      Vessel Detection 

      Aircraft Detection 

      Basic NCD

      uuid

      		  

      geometrySource

      		  

      detectionNumber

      		  

      label

      		      

      area

      		    

      classificationDetails

      		  

      sarLatitude

      		  

      sarLongitude

      		  

      sarLength

      		    

      sarWidth

      		    

      sarHeading

      		    

      sarDetectionTimeUTC

      		  

      sarDetectionConfidence

      		    

      sarChipIdentifier

      		    

      sarImageIndex

      		    

      aisCorrelationConfidence

      		    

      aisMmsi

      		    

      aisImo

      		    

      aisPredictionTimeUTC

      		    

      aisLatitude

      		    

      aisLongitude

      		    

      aisSpeed

      		    

      aisCourse

      		    

      aisHeading

      		    

      aisLength

      		    

      aisWidth

      		    

      aisName

      		    

      aisFlag

      		    

      aisShipType

      		    

      aisShipClass

      		    

      aisCallsign

      		    

      aisDraught

      		    

      aisDestination

      		    

      aisEta

      		    

      aisTrackIdBefore

      		    

      aisTrackIdAfter

      		    

      aisEstError

      		    

      aisErrorSemimajor

      		    

      aisErrorSemiminor

      		    

      aisErrorOrientation

      		    

      aisPredictionAlgorithm

      		    

      aisPredictionConfidence

      		    

      stsProbability

      		    

      stsSecondMmsi

      		    

      stsSecondClass

      		    

      stsTransferType

      		    

      rfDataIndex

      		    

      rfLatitude

      		    

      rfLongitude

      		    

      rfDetectionTimeUTC

      		    

      rfDetectionConfidence

      		    

      rfGeolocationErrorSemiMajorAxis

      		    

      rfGeolocationErrorSemiMinorAxis

      		    

      rfGeolocationErrorOrientation

      		    

      rfCenterFrequencyHz

      		    

      rfSignalBandwidthHz

      		    

      rfSignalType

      		    

      rfChannel

      		    

      rfModulationScheme

      		    

      rfReceivedPower

      		    

      rfMmsi

      		    

      rfMmsiConfidence

      		    

      rfNumberOfBursts

      		    

      rfMaxBursts

      		    

      rfPulseRepetitionFrequency

      		    

      rfPulseLength

      		    

      changeType

      		    

      changeMetric

      		    

      changeReferenceDateUTC

      		    

      changeDetectionDateUTC

      		    

      classificationCategory

      		  

      classificationType

      		  

      classificationSubtype

      		  

      classificationClass

      		  

      classificationModel

      		  

      classificationProbability