Fig. 4
From: Establishing the fundamentals for an elephant early warning and monitoring system
The effect of sound enhancement. a The input spectrogram with a rumble at 35 s and several noise sources, e.g. broadband noise (label “A” and label “B”); b The enhanced spectrogram after signal enhancement. The energy of the spectro-temporal patterns related to the rumble is increased while the signal energy of the noise sources is attenuated (best viewed in color)