Hi Katerina,
MEG file formats are all proprietary, there is no standard that you could convert your data to.
Which MEG system is it? Is it a new commercial system that is not supported yet in Brainstorm, or are these some internal developments that you lead at your lab?
If this is a stable system with a fully described file format, we could help you adding the native support for it in Brainstorm. We would need:
- A Matlab function to read the file headers (eg. similar to in_fopen_ctf.m)
- A Matlab function to read a block of recordings in a continuous file or MEG recordings (eg. in_fread_ctf.m)
- Some example files
- Links to online documentation of this file format
- The description of the geometry of your MEG sensors added to the file coil_def.dat:
https://github.com/brainstorm-tools/brainstorm3/blob/master/toolbox/io/private/coil_def.dat
https://martinos.org/mne/stable/manual/source_localization/coil_geometries.html
If this is a system that is under development, you'd need to figure out how to import your files to the database by yourself. For testing purposes, the simplest option is to create a channel_...mat and and one or more data_...mat file in a folder of the database, and then right-click on the folder in the Brainstorm database explorer > Reload.
https://neuroimage.usc.edu/brainstorm/Tutorials/ChannelFile#On_the_hard_drive
https://neuroimage.usc.edu/brainstorm/Tutorials/Epoching#On_the_hard_drive
If you want to work on a more formal integration, you could write your own your own in_fopen and in_fread functions. Let me know if you are interested, I could give you additional details on all the functions to modify.