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NIRS _coordsystem.json naming for space

Open JBusgang opened this issue 5 months ago • 2 comments

Your idea

Given the similarities between EEG and NIRS' electrodes/optodes systems, it could be useful to normalize the naming convention for the _coordsystem.json file with the standard set by EEG. That is to say: defining the space type for the coordinate system inside the name of the file.

Current EEG _coordsystem.json naming convention: Image

Current NIRS _coordsystem.json naming convention: Image

Including an optional field mimicking this [_space-

JBusgang avatar Jul 23 '25 20:07 JBusgang

Just to be clear, the purpose of space-<label> for (i)EEG is to allow multiple coordinate systems to describe the positioning of the same electrodes. Is that the goal of adding this to nirs?

effigies avatar Aug 27 '25 20:08 effigies

Hello,

Yes, the goal is to allow multiple coordinate systems to describe the positioning of the same electrodes, as for i(EEG).

Right now, this is done differently for NIRS. Optodes.TSV contains three columns, x, y, and z, containing the electrodes' coordinates according to the coordinate system. optodes.tsv can also contain the coordinate in a second coordinate system using template_x, template_y, and template_z.

I think this could be simplified using the same way as for i(EEG): only one coordinate system per file; described using the 'space' keyword.

From a software point of view, it would also be easier if EEG and NIRS followed the same convention for the electrode position description.

Let me know if you think i could open a PR for this.

Edouard2laire avatar Aug 29 '25 16:08 Edouard2laire