What dataformats are supported?
FieldTrip has a flexible way for supporting data formats. It uses a small number of reading functions that provide a common interface to all electrophysiological (MEG/EEG) and MRI file formats: ft_read_header, ft_read_data and ft_read_event. Where needed, these functions will call the appropriate low-level functions that are specific to the file format. Some of the low-level functions are written by ourselves, others are supplied by the manufacturers and again others are obtained from other open source toolboxes. You can find more technical information on the reading functions on this page.
What follows is a summary of the data formats that are supported by FieldTrip. You can find more details on some of the formats, especially regarding the different MEG systems and their auxiliary files (e.g., MRI and volume conduction models). We regularly implement new data formats and this documentation may be out of date, so if yours is not listed here, please check the code.
The following MEG data formats are supported by ft_read_header, ft_read_data and ft_read_event:
- CTF (.ds, .res4, .meg4)
- Neuromag/Elekta/MEGIN (.fif)
- BTi/4D (.m4d, .pdf, .xyz, and 4Dās raw data files)
- Yokogawa/Ricoh (.ave, .con, .raw)
- ITAB
- Tristan BabySquid
The following EEG data formats are supported by ft_read_header, ft_read_data and ft_read_event:
- ANT Neuro (.avr, .cnt, .trg)
- BESA (.avr, .swf)
- Biosemi BDF (.bdf)
- BrainVision (.eeg, .seg, .dat, .vhdr, .vmrk)
- CED - Cambridge Electronic Design (.smr)
- EEGLAB (.set, .fdt)
- Electrical Geodesics, Inc. (EGI) (.egis, .ave, .gave, .ses, .raw, .mff)
- NeuroScan (.eeg, .cnt, .avg)
- Nexstim (.nxe)
- TMSi (.Poly5)
- generic standard formats (.edf, .gdf)
The following EEG/MEG sensor formats are supported by ft_read_sens:
- All supported MEG formats (CTF, Neuromag/Elekta/MEGIN, BTi/4D, Yokogawa/Ricoh)
- ASA electrode file
- BESA positions (numeric file with accompanying .elp and .ela)
- BESA (.sfp)
- CTF Polhemus recording, which is used at the Donders also for EEG electrodes
- EEGLAB electrode positions
- FIL Polhemus recording
- SPM5/SPM8/SPM12 electrode positions
The following spike and LFP data formats are supported by ft_read_spike and ft_read_data:
- Plexon (.nex, .plx, .ddt)
- Neuralynx (.ncs, .nse, .nts, .nev, .nrd, .dma, .log)
- CED - Cambridge Electronic Design (.smr)
- MPI - Max Planck Institute (.dap)
- Windaq (.wdq)
The following NIRS data formats are supported by ft_read_header, ft_read_data and ft_read_event:
- Artinis Medical Systems (.oxy3, .oxy4)
- ASCII-formatted data from the NIRS system from Birkbeck college, London (.txt)
- Homer (.nirs)
The following eye-tracker data formats are supported by ft_read_header, ft_read_data and ft_read_event:
- SR Research EyeLink (.asc)
- SMI - SensoMotoric Instruments (.txt)
- Tobii (.tsv)
The following anatomical MRI data formats are supported by ft_read_mri:
- NIFTI (.nii / .nii.gz), using the FreeSurfer toolbox
- mgz (.mgz), using the FreeSurfer toolbox
- Analzye (.hdr, .img), using the SPM toolbox
- MINC (.mnc), using the SPM toolbox
- CTF (.mri)
- ASA (.mri, .iso)
- DICOM (.ima, .dcm)
The following surface and volume mesh formats are supported by ft_read_headshape:
- Generic meshes (.stl, .off)
- Visualisation Toolkit (.vtk)
- Stanford Triangle Format (.ply)
- Wavefront (.obj)
- gifti
- Tetgen
- BrainVista
- Caret
- FreeSurfer
- BrainSuite
See also
- How can I append the files of two separate recordings?
- What dataformats are supported?
- How are the various MATLAB data structures defined?
- How can I convert an anatomical MRI from DICOM into CTF format?
- How can I convert one dataformat into an other?
- How can I extend the reading functions with a new dataformat?
- How can I import my own data format?
- How can I merge two datasets that were acquired simultaneously with different amplifiers?
- I have problems reading in neuroscan .cnt files. How can I fix this?
- Reading is slow, can I write my raw data to a more efficient file format?