Fig. 9
From: Alternative measurement systems for recording cardiac activity in animals: a pilot study
Comparison of the noisy and filtered signals with significant peaks highlighted: a noisy ECG signal from the LL lead in the goat and b is the ECG signal after application of the IIR Buttherworth filter, R peaks are marked red c noisy BCG signal from horse, and d the BCG signal filtered by IIR-WT, J peaks are marked red