I modified the ODF average tool developed by Thomas Durantel. The three major modifications are:
1- Make the tool work with ODF which don't integrate to 1 over the sphere (notably fiber-ODF from CSD or MSMT-CSD) by adding a normalization step and a step to cancel the normalization at the end
2- Perform averaging computations only when necessary: if all inputs are null vectors, we simply output a null vector, and if only 1 input is not null, we simply output the latter
3- Use of spherical design points instead of a grid on the sphere for getting an ODF in sampled form. Spherical designs enable to compute sums on the unit sphere instead of integrals without any loss of information
I added many comments to explain what is being done.