The elegant method is to modify the LabVIEW code of the (open-source) "Reducer" tool available from
http://www.biosemi.com/download/Reducer.zip (or for LabVIEW 8.6.1:
http://www.biosemi.com/download/ToolsFo ... Engine861/). Modifying the code to overwrite the channel labels in the header with the list from a 32-chan CFG is a fairly easy and limited LabVIEW programming job.
Alternatively, proceed as follows with a less elegant, but nevertheless effective method:
- use "Reducer" tool to delete the 32 unused channels from the BDF file (the original BDF file is left unchanged as a backup)
- use "Cropper" tool to split the reduced BDF file in two halves, with the first halve containing the first second, and the second half containing the rest of the file
- open the 1 second BDF file in a file editor (e.g. Notepad)
- edit the channel names, while being extremely cautious to leave the total file length unchanged (or the file will become unreadable by BDF readers).
- use the "Merger" tool to add the second half BDF file to the modified 1 second BDF file.
Note: the reason for splitting and merging the file is that loading a BDF file with a length of more than a few seconds in Notepad may take ages.
Best regards, Coen (BioSemi)