A plug-in is needed that will export the number of limbs, the number of frames, and the XYZ Euler rotation values all to a .txt file that the user chooses. I was using the BVH exporter and parsing the BVH files, but that plug-in tries to convert quaternions to XYZ Euler angles, which results in bad data. A plug-in that accesses the same XYZ Euler rotation values used by Blender instead of trying to convert things is needed for this. Here is an example of the output:
4 1 15 30 45 0 90 180 4 -10 3 1 99 5
The first line has the number of limbs followed by the number of frames. The following lines have the XYZ Euler rotation values for each limb for each frame of the selected animation.