libDM_stream_logger is the interface library between the application and the SD card. It will log binary data, log text file, mavlink or protobuf messages inside a protobuf encoded binary file on the SD card. The binary file logged allows fast read and write operations (22mo/s read/write for teensy 4, 5-3 mo/s for esp32s3) thanks to buffering. The C++ program included allows fast conversion of the binary file to .mat matlab file or csv. Text data and mavlink/protobuf events will be extracted as json files.