Figure 1
From: Heart energy signature spectrogram for cardiovascular diagnosis
![Figure 1](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2F1475-925X-6-16/MediaObjects/12938_2006_Article_224_Fig1_HTML.jpg)
(A, B). Schematics of the Heart Sound Structure and Energy Signature Map. A) Schematic heart sound s wave form display (phonocardiogram -PCG). Second heart beat shows schematically S2 split. B) Energy Signature joint time-frequency map.