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":"7595700",

"capture_timestamp":"1638961134132",

"frame_timestamp":"1638961134132653",

"capture_ts":"1638961134132000000",

"datetime":"20231905 125854132",

"plateText":"\u0043\u0041\u0032\u0032\u0032\u0038\u0041\u004d",

"plateUnicode":"\u0043\u0041\u0032\u0032\u0032\u0038\u0041\u004d",

"plateUTF8":"CA2228AM",

"plateASCII":"CA2228AM",

"plateCountry":"UKR",

"plateConfidence":"0.708942",

"carState":"new",

"roiID":"1",

"geotag":{"lat": 50.418114,"lon": 30.476213},"imageType": "frame","plateImageType": "jpeg","plateImageSize": "0","carMoveDirection":"unknown",

"timeProcessing":"0",

"plateCoordinates":[1193, 439, 98, 20],

"plateCoordinatesRelative":[1176, 439, 98, 20],

"carID":"521893",

"GEOtarget":"Camera",

"imagesURI":["/local/fflprapp/tools.cgi?action=getImage&name=24/20231905105854_132_lp_CA2228AM_UKR_Opel_Astra G_SILVER.jpg","/local/fflprapp/tools.cgi?action=getImage&name=25/20231905105854_132_roi_CA2228AM_UKR_Opel_Astra G_SILVER.jpg"],

"imageFile":"/var/spool/storage/SD_DISK/fflprapp/images/25/20231905105854_132_roi_CA2228AM_UKR_Opel_Astra G_SILVER.jpg",

"vehicle_info":{"brand":"Opel","model":"Astra G","type":"CAR","color":"SILVER","confidenceMMR":"96.657967","confidenceColor":"97.237495","coordinates":[1012, 272, 458, 272]},

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

"sensorProviderID":"defaultID_175"

}

​


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