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Starting with OpenSim 4.0, C3D reading and conversion into OpenSim formats is available. Currently, use of C3D reading is limited to C++ and scripting and we will be working to support direct C3D reading in the GUI in future releases. The easiest way to use OpenSim to read your C3D data is through the Matlab interface. Once you have setup OpenSim use in Matlab, you can read C3D files and write marker and force data to .trc and .mot file formats, easily.
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