Figure 3.
ECG Recording and Signal Processing
(a) Raw data of a representative ECG waveform in the presence of gill motion and low frequency baseline wandering. R waves were detected by using an in-house R wave detection algorithm. Specifically, all of the individual ECG signals were aligned with the peak R waves and were summed together to filter the unsynchronized breathing artifacts and wandering baselines. (b) A summed ECG waveform over 5 minutes was highlighted as the red ECG pattern while the black waveforms were the individual ECG signals. (c) The residual baseline was then fitted with a cubic spline curve (blue) and subtracted from the summed ECG waveform.
