Request for AutoTRASSIR events

Examples of the requests: 

        https://192.168.1.200:8080/lpr_events?password=12345
        https://192.168.1.200:8080/lpr_events?sid=zxRc8Y7w
        https://192.168.1.200:8080/lpr_events?sid=zxRc8Y7w&dedup_timeout_sec=5

The requests use the following parameters:

  • password=12345 is the SDK password;
  • sid=zxRc8Y7w is the session ID;
  • dedup_timeout_sec=5 - the parameter that prevents republishing of an event with the same license plate number if it occurred within a specified time (e.g. 5 seconds) after the previous one. The parameter works only when authorization is performed using the sid parameter.

Example of a server response: 

[
{
    "best_guess" : "b663kt777",
    "channel" : "ilL0UhRy",
    "flags" : "1073741825",
    "id" : "63191",
    "lane" : "2",
    "lists" : "",
    "plate" : "b663kt777",
    "quality" : "98.90",
    "server" : "CyPy6vF5",
    "speed" : "0.00",
    "template" : "ru/rux3xx3-v1",
    "time_bestview" : "1393329818921734",
    "time_enter" : "1393329818802482",
    "time_leave" : "1393329819239768",
    "track_points" : [],
    "vehicle_type" : "car"
},
{
    "best_guess" : "p066ok77",
    "channel" : "ilL0UhRy",
    "flags" : "2147483717",
    "id" : "63190",
    "lane" : "1",
    "lists" : "",
    "plate" : "p066ok77",
    "quality" : "65.60",
    "server" : "CyPy6vF5",
    "speed" : "0.00",
    "template" : "ru/rux3xx2-v1",
    "time_bestview" : "1393329818524229",
    "time_enter" : "1393329818524229",
    "time_leave" : "1393329818762729",
    "track_points" : [],
    "vehicle_type" : "car"
}
]

Table 154. 

Properties Values Description Software version
"best_guess"   The most qualitatively recognized license plate number ≥4.0
"channel"   GUID of channel on which AutoTRASSIR module is used ≥3.1
"flags"   Flags describing event. ≥3.1
"id"   AutoTRASSIR event ID ≥3.1
"lane"   Traffic lane ≥3.1
"lists"   The list in which the given license plate number was detected ≥3.1
"plate"   Recognized AutoTRASSIR license plate number ≥3.1
"quality"   The best quality rate of the license plate number recognition ≥3.1
"server"   Server ID ≥3.1
"speed"   Vehicle speed ≥3.1
"template"   AutoTRASSIR template used for license plate number detection ≥3.1
"time_bestview"   The time the license plate number is recognized most qualitatively ≥3.1
"time_enter"   Time of the license plate appearance in the detection zone ≥3.1
"time_leave"   Time of the license plate number leaving the detection zone ≥3.1
"track_points"   The recognized numbers coordinates. The example of the coordinate request is described below ≥3.1
"vehicle_type" car, motorcycle, bus, truck, van Recognized vehicle body type ≥4.5

Tip

The response time is indicated in microseconds in UNIX-time format according to time zone configured on the server.

The flags parameter contains the description of AutoTRASSIR events: the driving direction, the lane number and the name of the list containing the recognized number. Each event is escribed with the help of bit mask, in which each bit corresponds to the specific information about the recognized number.

Table 155. 

Bit number Values Flag name Description
0 +1 LPR_UP Upward movement direction
1 +2 LPR_DOWN Downward movement direction
2 +4 LPR_BLACKLIST The number is in blacklist
3 +8 LPR_WHITELIST The number is in whitelist
4 +16 LPR_INFO The number is in informational list
5 +32 LPR_EXT_DB_ERROR Error in external list
6 +64 LPR_CORRECTED The number is corrected by the operator
29 +536 870 912 LPR_FIRST_LANE The vehicle is moving in the first lane
30 +1 073 741 824 LPR_SECOND_LANE The vehicle is moving in the second lane
29,30 +1 610 612 736 LPR_THIRD_LANE The vehicle is moving in the third lane

The meaning of the flags in the example above is:

  • 1073741825 is the value sum (1+1073741824) that corresponds to LPR_UP and LPR_SECOND_LANE. It means that the vehicle with this number is moving in the second lane upwards.
  • 1610612805 is the value sum (1+4+64+1610612736) that corresponds to LPR_UP, LPR_INFO, LPR_CORRECTED and LPR_THIRD_LANE. That means that the vehicle with this number is moving in the second lane upwards, and the vehicle number was edited by the operator after that detection and found in the information list.

To get the coordinates of the recognized license plates add to request &track_points=true.

Example of requesting AutoTRASSIR events with the coordinates of recognized license plates: 

        https://192.168.1.200:8080/lpr_events?sid=zxRc8Y7w&track_points=true

Example of a server response: 

[
{
    "best_guess" : "b663kt777",
    "channel" : "ilL0UhRy",
    "flags" : "1073741825",
    "id" : "63191",
    "lane" : "2",
    "lists" : "",
    "plate" : "b663kt777",
    "quality" : "98.90",
    "server" : "CyPy6vF5",
    "speed" : "0.00",
    "template" : "ru/rux3xx3-v1",
    "time_bestview" : "1393329818921734",
    "time_enter" : "1393329818802482",
    "time_leave" : "1393329819239768",
    "track_points" : [
    {
       "h" : 8.25,
       "w" : 18.75,
       "x" : 41.5,
       "y" : 35.75
    },
    {
       "h" : 7.5,
       "w" : 17.25,
       "x" : 40,
       "y" : 37.25
    }
    ],
    "vehicle_type" : "car"
}
]

Table 156. 

Properties Values Description Software version
"h"   The height of the recognized license plate number ≥3.1
"w"   The width of the recognized license plate ≥3.1
"x"   Horizontal axis position of the top left corner of the recognized license plate number in the frame ≥3.1
"y"   Vertical axis position of the top left corner of the recognized license plate number in the frame ≥3.1

Tip

Parameter values are indicated as a percentage of the frame size.

See also