Introduction
Milesight Intelligent Traffic cameras support integration with back-end devices via TCP, HTTP, MQTT, and Metadata. This document outlines some common data pushing issues and their solutions.
Note
This document is written based on firmware version T_61.8.0.4.
Issues
1. Unable to receive LPR messages on the HTTP server
2. Unable to receive the LPR messages on Milesight NVR or Milesight VMS Enterprise
3. Unable to receive the LPR messages from an MQTT subscriber
4. Unable to receive LPR messages over ONVIF metadata transmission
Solution
1. Unable to receive LPR messages on the HTTP server
a. Checking the network connectivity & server information
The network connection between the camera and the server has to been ensured. To test this out easily, you can use tools like Postman. You can download Postman app here.
To test out if the camera can access the server from the network that it is in right now, please connect the computer used for testing to the same network as the camera.
Step:
1) Launch Postman
2) Create a new POST request to your HTTP server:
Figure 1 Request Creation in Postman
3) Put in the authorization information if needed:
Figure 2 Authorization
4) Hit “Send”
5) Check out the response:
If you get an HTTP response with “200 OK” status, the connectivity and the server information is correctly set:
Figure 3 200 OK Message
If you get an HTTP response with status codes other than “200 OK”, it indicates that there’s something wrong in the configuration.
Exception Messages:
l401 Unauthorized: the server is accessible, but the authorization information is incorrectly set. Please confirm that that username and the password of the server is correctly input.
Figure 4 401 Unauthorized Message
l404 Not found: the server is accessible, but the page/interface you are trying to access does not exist/is not implemented. Please check out the set up on your server that you have implemented corresponding interface.
Figure 5 404 Not Found Message
l500 Internal Error: the server is accessible, but it cannot handle the request you have transmitted. Please check out the implementation code of your server, especially the part where is meant to handle the requests.
If you get prompts like “Error: Request timed out” and “Error: read ECONNRESET”, it indicates that the HTTP server is not accessible. Please confirm that the correct server address, port and context path is configured.
Figure 6 Connection Reset
Figure 7 Connection Timeout
You can also use curl to test out the accessibility to a certain HTTP server, with command
curl – v <the address to the server>:<port>/[context path]
Figure 8 Accessible Server
Figure 9 Inaccessible Server
b. Investigating size constraints
Some servers would block HTTP request with big sizes. LPR messages contain snapshots from the camera, which sometimes can go larger than 1 Megabyte. If you are not sure if this is the causation, you can test out as follows:
1) Navigate to Configuration > Data Transmission > Post > Data Settings
Figure 10 Data Format
2) Set mode to Import File and delete parts that include snapshots
Figure 11 Snapshot-related Elements
3) Save and see if the messages are transmitted successfully to the server. If so, please lift any size restrictions set on your server’s end.
2. Unable to receive the LPR messages on Milesight NVR or Milesight VMS Enterprise
Both Milesight NVR and Milesight VMS Enterprise only support TCP message with Original format. These configurations should be properly configured before the back-end receives plate messages correctly.
Steps:
1) Navigate to Data Transmission > Post > Post Settings > TCP
2) Make sure the transmission is enabled
3) In Select Events, make sure LPR is ticked
4) Camera Port need to be 3344, which is the default setting for LPR TCP transmission
Figure 12 TCP Transmission
5) Navigate to Settings > Data Transmission > Post > Data Settings
6) Set Mode as Original and hit the Save button to save changes
Figure 13 Original Data Format
Note
Please note that both Milesight NVR and Milesight VMS Enterprise do not support retrieving the LPR results stored on the SD card of the camera. Make sure storage is properly set up on them. If you want to know more about how to retrieve LPR data on the back-end, please refer to Milesight NVR/CMS/VMS how to get LPR data from Milesight ANPR Camera.
3. Unable to receive the LPR messages from an MQTT subscriber
Milesight LPR cameras support publishing LPR messages with a specified topic to a MQTT broker, so that the messages can be taken use by subscriber endpoint(s). To ensure that the MQTT connection is viable, you have to make sure that the camera and the subscriber(s) can access the broker. You can use tools like MQTTX to perform the test.
Note
MQTT is only implemented on part of Milesight Intelligent Traffic cameras, including Traffic X, Indoor Parking Guidance Cameras and those whose model names end with PE.
Steps:
1) Connect the computer used for testing to the same network as the camera;
Figure 14 MQTT Configuration
2) Connect to the MQTT broker with the information you have configured on the camera:
Figure 15 MQTTX Client
3) If you can connect to the broker successfully, the broker is accessible from the camera.
4) Connect the computer to the same network as the subscriber that needs to receive the messages.
5) Try to connect to the server as step 2.
6) If you can connect to the broker successfully, the broker is accessible from the subscriber.
If both the camera and the subscriber can access the broker, but the subscriber is still having problem getting the message, please check on the broker and see if the top that the messages published to and the subscriber(s) subscribed is the same.
4. Unable to receive LPR messages over ONVIF metadata transmission
Milesight Traffic network cameras support LPR message transmission over ONVIF metadata. You need to enable it before making use of it.
Note
Metadata transmission of plate information is introduced since firmware version T_61.8.0.3-r12. Please make sure that you have upgraded to this or a later version before continuing.
Steps:
1) Navigate to Settings > Data Transmission > More.
Figure 16 Metadata Transmission
2) Enable Metadata Transmission and click the Save button to save changes.
If you still encounter issues in LPR message transmission, please contact [email protected] for technical assistance.
——— END ———