💬 How to convert
.blf from a CAN bus to
.csv in Python?
💡 What is BLF? The Binary Logging Format (BLF) is a proprietary
CAN log format from the automative company Vector Informatik GmbH.
💡 What is CAN? The Controller Area Network (CAN bus) is a message-based protocol standard for microcontrollers in vehicles to communicate without a host computer.
Method 1: Using BLF Reader and CSV Writer
To convert the BLF file
'my_file.blf' to the CSV file
'my_file.csv', you can first iterate over the bus messages using
can.BLFReader('my_file.csv') and add the data to a list of lists. Then, you can use the
csv.writer() approach to write the list of lists to a CSV file.
Here’s an example that improves upon this SO thread:
import can import csv log =  for msg in list(can.BLFReader("my_file.blf")): msg = str(msg) row = [msg[18:26], msg[38:40], msg[40:42], msg, msg, msg[67:90]] log.append(row) with open("my_file.csv", "w", newline='') as f: writer = csv.writer(f, delimiter=',', quotechar='\"', quoting=csv.QUOTE_ALL) writer.writerows(log)
A more sophisticated version of this code is provided in this Github repository. Here’s a screenshot of the code — notice the more advanced processing of a single message compared to our solution:
Method 2: Using the candas Library
This is the provided example:
import candas as cd db = cd.load_dbc("dbc_folder") # This is the BLF file 'my_file.blf': log = cd.from_file("my_file") # This prints a signal from the messages in the BLF: print(log["AVGcellTemperature"])
Method 3: Using Custom Solution from python-can Library
You can use your tailor-made solutions by combining the Readers and Writers provided in the
It provides multiple utility functions such as:
Chances are you’ll find what you’re looking for when going over those functions!
Still not satisfied? I found the following relevant video when searching for a solution to this problem. I think you’ll find some nice tricks in the video!
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