Dereverberation parameter estimation device and method, dereverberation/echo-cancellation parameter estimation device, dereverberation device, dereverberation/echo-cancellation device, and dereverberation device online conferencing system

A reverberation/echo removal parameter estimation device comprising:

• a memory storing a parameter of a linear reverberation filter for removing a non-fluctuating reverberation component contained in a speech input signal, a parameter of a linear echo erasing filter for removing a non-fluctuating echo component contained in the speech input signal, and a parameter of a non-linear filter for removing a fluctuating reverberation component and a fluctuating echo component contained in the speech input signal;
• and
• a processor that estimates a reverberation/echo removal parameter for acquiring a direct sound by removing the reverberation component and the echo component contained in the speech input signal, and that stores the reverberation/echo removal parameter in the memory as the parameter of the linear reverberation filter, the parameter of the linear echo erasing filter, and the parameter of the non-linear filter,
• wherein the processor is configured to:
• read from the memory the parameter of the linear reverberation filter and the parameter of the linear echo erasing filter, and generates an estimated value of a linear reverberation/echo removal signal by removing the non-fluctuating reverberation component and the non-fluctuating echo component contained in the speech input signal using the linear reverberation filter and the linear echo erasing filter,
• read from the memory the parameter of the non-linear filter, and generates estimated values of the fluctuating reverberation component, the fluctuating echo component, and the direct sound component contained in the estimated value of the linear reverberation/echo removal signal, using the non-linear filter,
• update the parameters of the variation reverberation component, the fluctuating echo component, and the direct sound component constituting the parameter of the non-linear filter based on the estimated values of the fluctuating reverberation component, the fluctuating echo component, and the direct sound, and
• successively update the parameters of the linear reverberation filter and the linear echo erasing filter based on the updated parameters of the fluctuating reverberation component, the fluctuating echo component, and the direct sound component.

A dereverberation parameter estimation method including, using a processor, estimating a dereverberation parameter for acquiring a direct sound by removing a reverberation component contained in a speech input signal, and outputting the dereverberation parameter as a parameter of a linear filter for removing a non-fluctuating reverberation component contained in the speech input signal, and as a parameter of a non-linear filter for removing a fluctuating reverberation component contained in the speech input signal,

• the method comprising the steps of:
• the processor reading from the memory the parameter of the linear filter, and generating an estimated value of a linear dereverberation signal by removing the non-fluctuating reverberation component contained in the speech input signal using the linear filter;
• the processor reading from the memory the parameter of the non-linear filter, and generating estimated values of the fluctuating reverberation component and the direct sound component contained in the estimated value of the linear dereverberation signal using the non-linear filter;
• the processor, based on the estimated values of the fluctuating reverberation component and the direct sound, updating the parameters of the variation reverberation component and the direct sound component constituting the parameter of the non-linear filter;
• and
• the processor, based on the updated parameters of the fluctuating reverberation component and the direct sound component, successively updating the parameter of the linear filter.