Research Article
Wavelet-Based Semblance Methods to Enhance the Single-Trial Detection of Event-Related Potentials for a BCI Spelling System
Algorithm 2
Semblance-based ERP window selection by channels (SEWS-1).
(1) | Input: given the EEG signal matrix X, with C channels and T temporal samples | (2) | Output: the bounds of the temporal window and for each C channel | (3) | Set the window threshold , | (4) | for to C do | (5) | Compute the average of responses belonging to the target class for channel c | (6) | Compute the average of responses belonging to the nontarget class for channel c | (7) | Compute the and using equation (2) | (8) | Compute the semblance using equation (4) | (9) | Compute the dot product D using equation (5) | (10) | Compute the standard deviation of D over the scales and standardise it between 0 and 1 | (11) | The limit is given by the first t from the left which meets | (12) | The limit is given by the first t from the right which meets | (13) | end for |
|