The OpenSim 4.0 API includes methods for reading C3D data into OpenSim formatted files. Marker (.trc) and Forceplate (.mot) data can be created using The OpenSim C3DFileAdapter() class , which uses a forked version of Arnaud Barre's BTK package. Use of the C3DFileAdapter and included Matlab utilities are described is limited to C++ and scripting with example code below.
Reading C3D files through Matlab
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