J2735decoder

<h1 align="center"> V2X Communication Message Decoder </h1>

A Python library crafted to decode SAE J2735 encoded UPER HEX messages.

Built With

• pycrate
• J2735: Dedicated Short Range Communications Message Set

Getting Started

Note: The library has been tested on Ubuntu 22.04 and Windows 10.

Prerequisites

• Python 3

Install

You can install dependencies and the SAE J2735 ASN.1 Python package bundled in this repo as a wheel.

• Create and activate a virtual environment (recommended)

  python3 -m venv .venv
  source .venv/bin/activate
  

• Install required packages

  pip install -r requirements.txt
  

• Install the J2735 definitions package from the local wheel. You may install any of the wheels available. Example:

  pip install wheels/j2735_202409-*.whl
  

  Note: You will have to make sure your imports match your installed packages. Further information in the Usage section below.

Required Python Libraries

• Pycrate

pip install pycrate==0.7.11

• json2xml

pip install json2xml==5.2.1

[The following libraries are essential and should already be part of a standard Python3 installation:]

• json
• binascii

Usage: J2735_decode Function

1. Importing the Function:

To get started, first import the J2735_decode function from the CAVmessage.py module.

from CAVmessage import J2735_decode

Note: You may also set the desired J2735 V2X version in CAVmessages.py. Simply change the import name at the top of this file. It is currently defaulted to j2735_202409. You may change this to j2735_201603_combined.

2. Understanding the Function:

The function is designed to decode J2735 UPER hex payloads into XML or JSON.

• Primary Objective: Convert J2735 UPER hex into XML or JSON format.
• Inputs:
  • Payload: Represents the UPER hex payload intended for decoding.
  • FileSave (default value is False): When set to True, the decoded XML and JSON outputs are saved in the directory from which the script is executed.
• Outputs: The function provides a decoded J2735 message in both XML and JSON formats.

3. Utilizing the Function:

Basic usage:

decode = J2735_decode(payload)

To save outputs as files:

decode = J2735_decode(payload, True)

4. Extracting the Outputs:

• To retrieve the XML format:

  print(decode.xml)
  

• To retrieve the JSON format:

  print(decode.json)
  

5. Test Your Setup:

For an initial test, execute the main_test.py script. You can modify the payload values in this script as needed, and then inspect the XML and JSON outputs directly in the terminal.

Sample Data Insights

Within the Sample Data directory, you'll find "SampleHexPayloads.txt". This file contains several J2735 encoded UPER hex payloads. Corresponding decoded XML and JSON messages for these payloads are also available in the same directory.

Contributing to the Project

Your contributions enrich the open-source community, making it a vibrant place for learning, inspiration, and creativity. Every contribution, however small, is invaluable.

1. Fork the Project.
2. Spawn your Feature Branch (git checkout -b feature/YourFeatureName).
3. Commit the changes (git commit -m 'Introduce YourFeatureName').
4. Push to the branch (git push origin feature/YourFeatureName).
5. Initiate a Pull Request.

Get in Touch

For any queries or support, reach out to: CAVSupportServices@dot.gov.