pyFDN.echo_density#
- pyFDN.echo_density(ir, n=1024, fs=48000.0, pre_delay=0, mixing_thresh=1.0, hop=500)[source]#
Echo density and mixing time (Abel & Huang 2006).
Computes the transition time between early reflections and stochastic reverberation assuming sound pressure in a reverberant field is Gaussian distributed.
Reference: Abel & Huang (2006), “A simple, robust measure of reverberation echo density”, Proc. 121st AES Convention, San Francisco.
- Parameters:
ir (array-like) – Impulse response (1 channel only). Converted to 1D.
n (int, optional) – Window length (must be even). Default 1024.
fs (float, optional) – Sampling rate in Hz. Default 48000.
pre_delay (int, optional) – Onset delay in samples for mixing time. Default 0.
mixing_thresh (float, optional) – Normalized echo density threshold for mixing time (Abel & Huang use 1). Default 1.0.
hop (int, optional) – Hop size in samples for sparse analysis. Default 500.
- Return type:
- Returns:
t_abel (float) – Mixing time in milliseconds (time at which echo density first exceeds mixing_thresh, relative to pre_delay). 0 if not found.
echo_dens (np.ndarray) – Echo density vector (length = len(ir)), normalized; interpolated from sparse analysis.