Nippon Telegraph and Telephone Corporation

Ntt Corporation

Hitachi, Ltd.

Rintaro Ikeshita

Tomohiro Nakatani

Hiroshi Sawada

Shoko Araki

Nobutaka Ito

Keisuke Kinoshita

Yohei Kawaguchi

Naoyuki Kamo

An acoustic signal enhancement device includes: a spatiotemporal covariance matrix estimation unitconfigured to estimate spatiotemporal covariance matrices Rand P; a reverberation suppression unitconfigured to obtain a reverberation suppression filter Gof the sound source j using the estimated spatiotemporal covariance matrices Rand Pfor each sound source j and to generate a reverberation suppression signal vector using the obtained reverberation suppression filter Gand the observation signal vector X; a sound source separation unitconfigured to obtain an enhanced sound yof the sound source j and power of the sound source j using the generated reverberation suppression signal vector for each sound source j (where 1≤j≤J) corresponding to the target sound; and a control unitconfigured to perform control such that processes of these units are repeatedly performed.

Acoustic signal enhancement apparatus, method and program

There is provided an acoustic signal enhancement device that receives, as an input, a recording sound obtained by frequency division and updates parameters, the device including: assuming that a switch weight is a weight indicating a ratio of a classification to which a recording sound at each timing belongs in classifications of spatial states where a recording sound temporally changes, a beamformer unit that performs beamformer processing based on a weighted spatial covariance matrix which is updated and updates an auxiliary estimation value of a target sound; a switch unit that updates the switch weight and power of a target sound based on the updated auxiliary estimation value and outputs an estimation value of the target sound; and a weighted spatial covariance estimation unit that updates the weighted spatial covariance matrix based on the updated switch weight and the power.

Acoustic signal enhancement device, acoustic signal enhancement method, and program

A sound source signal generation technology based on an optimization algorithm that enables high-speed processing of sound source extraction is provided. A sound source signal generation device includes an optimization unit that optimizes a separation matrix W(f)=[w(f), . . . , w(f), W(f)] using an observed signal x(f, t), the optimization unit includes an auxiliary function calculation unit that calculates an auxiliary function V(f) (i=1, . . . , K) according to a predetermined equation, a first separation filter calculation unit that calculates a separation filters w(f) (i=1, . . . , K) using auxiliary functions V(f) (i=1, . . . , K) and V(f), and a second separation filter calculation unit that calculates a separation filter W(f) according to a predetermined equation when a convergence condition is satisfied.

Target source signal generation apparatus, target source signal generation method, and program

Provided is an acoustic signal enhancement device, including a time-space covariance matrix estimation unit configured to estimate a time-space covariance matrix corresponding to a sound source, using a power of the sound source and an observation signal vector composed of an observation signal from a microphone. A reverberation suppression unit is configured to obtain a reverberation removal filter of the sound source using the time-space covariance matrix, and to generate a reverberation suppression signal vector corresponding to the observation signal for an emphasized sound of the sound source using the reverberation removal filter and the observation signal vector. A sound source separation unit is configured to obtain an emphatic sound of the sound source and the power of the sound source using the reverberation suppression signal vector.

A sound source separation filter information estimation device () estimates a covariance matrix having information on a correlation between sound source spectra and information on a correlation between channels as information on sound source separation filter information for separating an individual sound source signal from a mixed acoustic signal.

Estimation device, estimation method, and estimation program

The signal separation device includes: cross product calculation means receiving an input of an observed signal that is a mixture of a plurality of target signals, and calculating a cross product of the observed signal; model calculation means updating a parameter of a model for estimating the cross product with a predetermined algorithm using an inverse matrix of a matrix that represents an estimate of the cross product; inverse matrix calculation means calculating the inverse matrix of a matrix by a SIMD command when the parameter is updated; and separation means calculating the target signals using a matrix representing an estimate of the cross product, the updated parameter, and the observed signal.

Signal separation apparatus, signal separation method and program

There is provided a sound source separation method of carrying out sound source separation of an audio signal inputted from an input device by using a modeled sound source distribution, by an information processing apparatus provided with a processing device, a storage device, the input device, and an output device. In this method, as a condition followed by the model, sound sources are independent of one another, powers which the sound sources have are modeled for each of frequency bands obtained through band division, a relationship among the powers for the frequency bands different from each other is modeled by nonnegative matrix factorization, and components obtained through the division of the sound source follow a complex normal distribution.

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Tokyo, Japan

Rintaro Ikeshita