SigViewer is a powerful viewing application for biosignals designed to display electroencephalographic (EEG) and other biosignal data. SigViewer supports several biosignal data formats through libbiosig (for example GDF, EDF, CNT, EEG, and many more). Besides displaying biosignals, SigViewer supports creating annotations to select artifacts or specific events. SigViewer also features basic signal processing modules such as computing the average over selected epochs (yielding event-related potentials) and the power spectrum of selected signals.
SigViewer is written in C++ using the cross-platform graphical user interface (GUI) toolkit Qt. SigViewer is open source and available for all three major platforms (Windows, Mac OS X, and Linux). The application is licensed under the GNU GPL.