When measuring echolocation clicks, there are multiple ways to make some measures of amplitude, for example peak-to-peak, RMS or energy flux density (EFD). Peak-to-peak and RMS are simple, however, I am trying to measure energy flux density which is regularly used in studies of impulsive noise and also echolocators (useful because the mammalian ear acts roughly as an energy detector that integrates intensity over a time window). The actual EFD equation is pretty simple – it’s just $EDF = RMS_{dB} + 10\log(T)$ where $RMS_{dB}$ is the RMS amplitude in dB re 1 µPa and $T$ is the time in seconds.
My question is how do we measure $T$ for a click i.e. what convention should be used to find the start and end of an echolocation click and what are the signal processing approaches to achieve this? If it’s any help, I am studying harbour porpoise clicks but would be interested in other echolocation clicks/calls if methods differ between species.