http://6swc2kxdtxwqku6ieo2bppmehqo3dncdaznvytb37fbsnanlkci3rbid.onion/stretch/main/metainfo/sigviewer.html
It relies on biosig4c++ library which supports
a number of data formats (including EDF, BDF, GDF, BrainVision, BCI2000, CFWB, HL7aECG, SCP_ECG (EN1064), MFER, ACQ, CNT(Neuroscan),
DEMG, EGI, EEG1100, FAMOS, SigmaPLpro, TMS32). The complete list of supported file formats is available at http://pub.ist.ac.at/~schloegl/biosig/TESTED
.</p>
<p>Besides displaying biosignals, SigViewer supports creating annotations to select artifacts or specific events.