Energy Decay Relief
The energy decay relief (EDR) is a time-frequency distribution
which generalizes the EDC to multiple frequency bands :
of the short-time Fourier transform
) at time-frame
denotes the total number of time frames. The FFT
within the STFT is
typically used with a window, such as a Hann window
of length 30 or 40
is the total amount of signal energy remaining
in the reverberator's impulse response at time
in a frequency band centered
Hz, where denotes the FFT length.
The EDR of a violin-body impulse response is shown in Fig.3.2.
For better correspondence with audio perception, the frequency axis is
warped to the Bark frequency scale , and energy
is summed within each Bark band (one critical band of hearing equals
one Bark). A violin body can be regarded as a very small reverberant
room, with correspondingly ``magnified'' spectral structure relative
to reverberant rooms.
Energy Decay Relief of a violin-body impulse response
The EDR of the Boston Symphony Hall is displayed in [153, p.
The EDR is used to measure partial overtone dampings from recordings
of a vibrating string in §6.11.5.
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