The process of converting BLF (Binary Logging Format) to MF4 (Measurement Data Format v4) is a standard procedure in automotive engineering to move data from raw CAN bus captures into a structured, signal-based format for advanced analysis. Methods of Conversion
Vector Software (Standard GUI Method)The most reliable way to convert these files is using native Vector Informatik tools like CANoe, CANalyzer, or CANape.
Vector Logging Converter: Located under Tools | Measurement File Converters in CANape or vSignalyzer, this utility can ingest .blf files and output signal-based .mf4 files.
Database Requirement: To get a "new" signal-based MF4 from a message-based BLF, you must attach the appropriate database files (such as .dbc for CAN or .ldf for LIN) within the converter settings.
Python Automation (Developer Method)For batch processing or "new" custom workflows, the asammdf library combined with candas is the industry standard.
Workflow: Use candas to parse the BLF messages against a DBC file, then pass the resulting data into an asammdf object to save as an MF4. Example Logic:
import candas as cd from asammdf import MDF, Signal # Load logs and databases log_data = cd.from_file(cd.load_dbc("path/to/dbc"), "input.blf") mdf = MDF() # Append signals to the new MF4 object for name, values in log_data.items(): mdf.append(Signal(samples=values, timestamps=log_data.index, name=name)) mdf.save("output.mf4") Use code with caution. Copied to clipboard Standalone Utilities
BLFConvert.exe: A specific Vector utility used primarily for reformatting Ethernet-based BLF files from channel-based to network-based, which can then be exported to other formats.
CSS Electronics Converters: If you are using CANedge hardware, standalone MF4 Converters are available to handle various log transitions. Why Convert to MF4? Database Selection for Vector Logging Converter
Converting BLF (Binary Logging Format) to MF4 (Measurement Data Format 4) is a standard requirement for automotive data analysis, transitioning from proprietary Vector formats to the open ASAM standard. As of 2026, new workflows increasingly favor open-source Python automation alongside traditional Vector software suites. 1. Professional Desktop Tools
Vector tools remain the industry standard for high-fidelity conversion, ensuring all metadata and timestamps are preserved.
Vector Logging Converter: This standalone utility or integrated feature in CANape/CANoe converts message-based BLF logs into signal-based MF4 logs.
New Feature Highlights: Modern versions support embedding database paths directly within the MF4 (v4.10+) for easier portability.
Vector CANoe/CANalyzer: Use the "Logging" or "Measurement" configuration to replay BLF files and record them directly as MF4.
PEAK-Converter: A robust alternative for those using PEAK hardware, it supports converting third-party formats like BLF to MF4 for cross-platform analysis. 2. Automated Python Workflows
For large-scale data processing, Python-based conversion is the modern approach.
asammdf + candas: While asammdf is the premier library for MF4 editing, it often requires a helper like candas to ingest BLF files. convert blf to mf4 new
import candas as cd import asammdf # Load BLF and DBC dbc = cd.load_dbc("./database.dbc") log_data = cd.from_file(dbc, "input.blf") # Save to MF4 mdf = asammdf.MDF() # Logic to append signals from dataframe to mdf object mdf.save("output.mf4") Use code with caution. Copied to clipboard
python-can: Use the logconvert module for simple CLI-based conversions. python -m can.logconvert input.blf output.mf4 3. Key Technical Considerations Convert .blf to mdf or mf4 in Python - Stack Overflow
To convert BLF (Binary Logging Format) files to MF4 (Measurement Data Format v4), you can use professional automotive software, specialized Python libraries, or dedicated conversion tools. This process typically requires a DBC file to decode message-based BLF data into signal-based MF4 data. Professional Software Solutions
Vector CANoe/CANalyzer: These tools have a built-in Log File Conversion feature. Go to the "Offline" or "Analysis" tabs to find the "Log File Converter".
Vector CANape/vSignalyzer: Use the Vector Logging Converter found under Tools | Measurement File Converters. You must add the appropriate database (DBC/ARXML) in the options dialog to ensure signals are correctly translated.
Vector CallConverter: A command-line tool that can be automated via scripts to batch-convert files. Python-Based Methods (For Automation)
If you prefer a scripted approach, several libraries support this workflow:
asammdf: A powerful library for handling MF4 files. You can combine it with CANdas to read BLF data and save it as an MF4.
cantools: A set of libraries and command-line tools that can parse and convert various automotive formats, including BLF and MDF.
python-can: Provides basic IO support for BLF and MF4 writing. Free & Open-Source Tools Convert .blf to mdf or mf4 in Python - Stack Overflow
Converting BLF (Binary Logging Format) to MF4 (Measurement Data Format v4) usually requires a database (like a .DBC or .ARXML file) to translate raw CAN messages into readable signals. Software Tools
Vector CANoe/CANalyzer: Use the built-in Log File Conversion tool located under the Tools menu to convert logs without needing external software.
Vector Logging Converter: Specifically designed to combine raw log files with database information to generate signal-based MF4 files.
PEAK-Converter: A Windows tool that can convert various trace formats, including third-party ones, into MF4 files.
CSS Electronics Converters: Offers a suite of MF4 converters often used with CANedge data loggers. Python (For Automation)
If you prefer a scripted approach, you can use the asammdf and candas libraries. The process of converting BLF (Binary Logging Format)
import candas as cd import asammdf # Load database and log dbc = cd.load_dbc("path_to_database.dbc") log_data = cd.from_file(dbc, "input.blf") # Convert to MF4 mdf = asammdf.MDF() # ... process signals ... mdf.save("output.mf4") Use code with caution. Copied to clipboard Community Perspectives
“I had to go through Vector CANalyzer to convert files individually. Would be great to find a solution via Python.” Stack Overflow · 2 years ago
“You can use the CANdas library to read the blf using your multiple dbc files... and add it to a mdf file using asammdf.” Stack Overflow · 2 years ago
Do you have the .DBC database files ready for the conversion, or Convert .blf to mdf or mf4 in Python - Stack Overflow
BLF is compressed; MF4 by default is not.
Solution: Enable deflate compression during conversion:
asammdf: compression=2The most reliable free tool is Vector's BLF2MDF (command line). For a GUI, use asammdf (Python GUI) or CANape (commercial).
Best for flexibility, scripting, and inspecting data.
pip install asammdf[gui]
asammdf in terminal → File → Convert → Select BLF → Output format MF4.from asammdf import MDF
mdf = MDF("input.blf")
mdf.save("output.mf4", compression=2) # compression=2 = deflate
For embedded systems or batch processing servers, the official ASAM MDF4 library (or the compatible mdf4lib) is best.
Steps:
mdf4lib from GitHub (or Vector’s MDLib).xllapi.h).Pseudocode:
#include "mdf4.h" #include "xllapi.h" // for BLF readingint main() // Open BLF XLblfOpen("log.blf", &blfHandle);
// Create MF4 file MDF4_FILE* mdf = mdf4_create("out.mf4", MDF4_COMPRESSION_DEFLATE); // Define a CAN bus group mdf4_add_channel_group(mdf, "CAN_Bus", 0); XLblfMessage msg; while (XLblfReadNext(blfHandle, &msg)) mdf4_write_can_frame(mdf, msg.timestamp, msg.id, msg.data, msg.dlc); mdf4_close(mdf); XLblfClose(blfHandle); return 0;
Note: Actual API calls differ – check the respective library documentation.
Converting BLF to MF4 is a standard workflow in automotive testing. While BLF is excellent for capturing data on Vector hardware, MF4 is the key to unlocking that data for the wider ecosystem of engineering tools.
asammdf.By converting to MF4, you ensure your data is future-proof, shareable, and compliant with industry standards. By converting to MF4
Yes, you can convert Vector BLF (Binary Logging Format) files to ASAM MDF4 (.mf4) files using both official Vector tools and open-source alternatives.
Converting message-based .blf data (like raw CAN bus traffic) to signal-based .mf4 data requires importing database network files (such as .dbc or .ldf) to properly decode the raw hex messages into physical, readable signals. 🛠️ Recommended Methods for Conversion 1. Official Vector Tools (GUI & Command Line)
If you already use a Vector toolchain, the built-in utilities provide the most reliable conversion path.
Vector Logging Converter (via CANape/vSignalyzer): CANape features the Vector Logging Converter to shift message-based logs into signal-based .mf4 files. It automatically references databases mapped in your active project.
Vector CallConverter: A native command-line utility used to batch process measurement files and perform conversions without opening heavy GUIs.
CANoe/CANalyzer: You can use the logging blocks or run offline playbacks to record incoming .blf streams straight into a designated .mf4 destination format. 2. Python Scripting (Automated & Free)
For high-volume automation, libraries like asammdf allow programmatic conversion of raw CAN data to .mf4. You can read BLF files, apply .dbc databases, and structure the data efficiently within Python. A common approach involves loading log data and mapping it directly to MDF4 channels. 3. Hardware-Specific Converters Alternative tools offer flexible, non-Vector solutions:
PEAK-Converter: Converts various trace formats to targeted files like .mf4.
CSS Electronics Converters: Ideal for standalone, drag-and-drop actions on Windows and Linux. ⚠️ Critical Checks Before You Convert Convert .blf to mdf or mf4 in Python - Stack Overflow
Converting BLF (Binary Logging Format) files to MF4 (Measurement Data Format v4) is a common task in automotive data analysis, typically performed to make log files compatible with third-party tools or for more efficient signal-based analysis. Recommended Conversion Tools
Depending on your technical setup, several industry-standard tools can handle this conversion:
Vector Logging Converter: This is the native solution for Vector users. It can convert message-based BLF files into signal-based MF4 logs. It often requires a database file (like a .DBC) to correctly map signals during the conversion process.
asammdf (Python/GUI): A highly recommended open-source tool. It provides both a Python API and a user-friendly GUI. You can use libraries like candas to read the BLF and then asammdf to save it as an MF4.
PEAK-Converter: If you use PEAK-System hardware, their PEAK-Converter for Windows supports converting various trace formats, including third-party ones, into MF4.
MATLAB (Vehicle Network Toolbox): MATLAB's blfread function allows you to read BLF data directly into timetables, which can then be processed or exported. Comparison of Formats Database Selection for Vector Logging Converter
Converting BLF to MF4 is no longer a headache. With modern libraries like asammdf supporting direct BLF ingestion and native compression, you can move from raw bus logs to analytics-ready measurement files in minutes.
The Bottom Line: Keep your DBC file handy, upgrade your Python libraries, and never email a raw BLF to a customer again.
Have a specific conversion scenario? Leave a comment below or reach out for a script template tailored to your toolchain.