The simple way to bring a mocap file into Houdini is to create it in a application that is compatible with FBX. This will allow you to import the animated skeleton with mocap baked in, as well as the skin. This will save you the trouble of rebinding the skin to the rig.

Another way to do this is to use one of Houdini’s stand-alone utility motion capture formats to convert one of the popular mocap file formats into .cmd and .bclip files. If you have a .bvh BioVision file use mcbiovision, if you have .asf and .amc Acclaim file use mcacclaim, if you have a .trc Motion Analysis file use mcmotanal, and run it through the Houdini Command Line Tools.

You can then import your .cmd file by selecting Run Script from the File menu or by using the Hscript Textport window. This will create the appropriate nodes, including a File CHOP that reads the .bclip file. If you don’t see your skeleton fully assembled and moving, check if the file path in the CHOP is correct. If your current $HIP is not the same directory as your .cmd and .bclip files, you will have to update the path to point to the proper directory and file.

Once the .cmd file is imported you can import geometry and bind it to the animation manually using the tools on the Characters tab of the shelf. For best initial results, it helps if your character and mocap skeletons are similar proportionally.