Hi,

Thanks for sharing this draft specification. Here are a few small (late) comments I'd like to share on the latest version.

Our new NIRS system should be released in a few months, and we made it very modular. The system can be made from any combination of up to 4 "blocks", each having the potential of having a different number of sources, detectors and wavelengths (as well as different wavelength values). 

That being said, I just wanted to make sure that the specification doesn't enforce the usage of all wavelengths available on the system for all measurements (I may be wrong, but I do believe it was the case for the Matlab based .nirs file format).

In the description of the "ml" structure, there is a note specifying that "source indices generally refer to the optode naming (probe positions)". I assume that it is the same for detectors?

In the optional variables, the "qform" variable specified a 4x4 matrix to align the NIRS coordinate system to other geometries. Would it be useful to have an additionnal variable that describes that geometry (ex: MNI, Talairach, anatomical, etc) ? I am thinking of something that may be similar to the NIfTI file format.

Also, are there any constraints in terms of endianness of the file, and/or type encoding of the different variables?

Thank you,

Mathieu Coursolle
Rogue Research Inc.