JSON Fields and Example for Protocol 1.6 in License Plate Recognition

JSON Fields (Protocol 1.6) \ JSON example


Token

Type

Format / Value

Description

packetCounter

Unsigned int


Counter of packets. Starts from “1”. Counter starts after successful connection or after start of device. It does not matter.

datetime

string

YYYYMMDD HHMMSSFFF


YYYY - year 4 digits

MM - month 2 digits ( with leading 0 )

DD - day 2 digits ( with leading 0 )(space)

HH - hours

MM - minutes

SS - seconds

FFF - milliseconds

TimeZone in form +-HHMM optional.


%Y%m%d %H%M%S%3d

plateUTF8

UTF string

"RZ3832H"


plateUnicode

Unicode string

"RZ3832H"


plateText

Unicode string

\u0041\u0041….

Plate number in the unicode translation

https://www.branah.com/unicode-converter

plateCountry

ASCII string

[DNK,......UKR]

Country, ISO3166, ALPHA3

plateConfidence

float


Recognition confidence

carState

ASCII string

[new,updated,lost]

Event type. 

geotag: {
“lat”:,”lon”:
}

Json object with 

floats

50.418114,30.476213

Latitude, longitude

imageType

ASCII string

“plate” | “mmrcrop” | “vehicle” | “frame”

The kind of attached image: plate only rectangle with plate number, frame - full frame.

plateImageType

ASCII string

[png,jpeg,bmp]

The type of attached image. HTTP header must use the same type with header 

Content-type: image/...

plateImageSize

Unsigned long

0

The size in bytes of attached image, may be zero.

carMoveDirection

string

[unk,in,out]

The kind of detected movement

timeProcessing

Unsigned int


Time of image processing. ms

plateCoordinates

Array of unsigned int

[left,top,width,height]

Plate coordinates

carID

Unsigned long long


Internal runtime plate ID

sensorProviderID

ASCII string


The Human name of sensor

roiID

Unsigned int

1,2

Number of region of interest. ACAP support max 2 

frame_timestamp

unsigned long long

155131902113266

The returned value is nanoseconds for the system uptime(Frame time)

capture_timestamp

unsigned long long

1558090545839

Obtain the timestamp of the media_frame, measured in nanosecond. in the millisecond

capture_ts



To be deprecated

"vehicle_info":{"brand":"l",

"model":"","type":"","color":"",
"confidenceMMR":"",
"confidenceColor":"",
"coordinates":[]},

string

"vehicle_info":{"brand":"Opel","model":"Astra G",

"type":"CAR","color":"SILVER"
,"confidenceMMR":"96.657967",
"confidenceColor":"97.237495",
"coordinates":[1012, 272, 458, 272]},

Vehicle recognition date

Brand

Model 

Type

Color 

Confidence level  for MMR

Confidence level  for Color

Vehicle coordinated

imagesURI

string

["/local/fflprapp/tools.cgi?action=getImage&name=

2/20230519165230_615401lp_
H634TK750_210.jpg",
"/local/fflprapp/tools.cgi?action=getImage&name=
3/20191010165230_618056roi_
H634TK750_210.jpg"],

List of available event images’ URIs

"camera_info":{"SerialNumber":"",

"ProdShortName":""
,"MACAddress":""},

"sensorProviderID":"

string

"camera_info":{"SerialNumber":

"ACCC8EA617EF",
"ProdShortName":
"AXIS P1445-LE","MACAddress":
"AC:CC:8E:A6:17:EF"},

"sensorProviderID":"defaultID_175"

Camera Serial Number

Camra name 

Camera MAC address

SensorProviderID (from application)


JSON example

{"packetCounter":"3821", "capture_timestamp":"1744745482179", "frame_timestamp":"0", "capture_ts":"1744745482179000000", "datetime":"20250415 123122179", "plateText":"\u0042\u004f\u004c\u0037\u0035\u0039\u0031", "plateUnicode":"\u0042\u004f\u004c\u0037\u0035\u0039\u0031", "plateUTF8":"BOL7591", "plateASCII":"BOL7591", "plateCountry":"USA", "plateISO3166-2":"US-WA", "plateType":"None", "plateRegion":"Washington", "plateRegionCode":"", "plateList":"", "plateListMode":"", "plateListDescription":"", "plateConfidence":"0.706800", "carState":"lost", "roiID":"1", "geotag":{"lat": 55.70421,"lon": 13.19366},"imageType": "frame","plateImageType": "jpeg","plateImageSize": "0","carMoveDirection":"unknown", "timeProcessing":"0", "plateCoordinates":[270, 543, 126, 72], "plateCoordinatesRelative":[67, 135, 31, 18], "carID":"79520", "GEOtarget":"Camera", "imagesURI":["/local/fflprapp/tools.cgi?action=getImage&name=19/20250415123123_796468lpup_BOL7591_125890.jpg","/local/fflprapp/tools.cgi?action=getImage&name=13/20250415123122_324580roi_BOL7591_125881.jpg"], "frames":"0","imageFile":"localdata/images/13/20250415123122_324580roi_BOL7591_125881.jpg", "imageFile2":"localdata/images/19/20250415123123_796468lpup_BOL7591_125890.jpg", "profileID":"2", "vehicle_info":{"view":"front","brand":"Lexus","model":"IS/IS F","type":"CAR","color":"GRAY","confidenceMMR":"1.000000","confidenceColor":"0.889738"}, "camera_info":{"SerialNumber":"B8A44FD05150","ProdShortName":"AXIS P3265-LVE","IPAddress":"10.23.29.32","MACAddress":"B8A44FD05150"}, "sensorProviderID":"defaultID" }

​


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