Panasonic Intellectual Property Management Co., Ltd.

Panasonic Corporation

Junji Araki

Shinichi Takayama

Takahiro Yamaguchi

Kenichi Kubota

Naoya Tanaka

Satoshi Abe

Yuji Suzuki

Toshihiro Ezaki

Hiromasa Ohashi

Masaru Matsuoka

The voice control device includes a sound source signal input unit, a frequency determination unit, a band controller, a sound image controller, and a voice output unit. The sound source signal input unit inputs a sound source signal of content from a sound source. The frequency determination unit determines a cutoff frequency. The band controller acquires a high frequency signal in a frequency band equal to or higher than the cutoff frequency and a low frequency signal in a frequency band equal to or lower than the cutoff frequency, from the sound source signal of the content. The sound image controller generates a plurality of sound image control signals for controlling sound images of the plurality of speakers, by controlling at least one of a phase and a sound pressure level of the high frequency signal. The voice output unit outputs the low frequency signal to a first speaker, and outputs the plurality of sound image control signals to a second speaker composed of a plurality of speakers.

Voice control device and voice control system

A noise reduction device includes a processor that converts a noise signal collected by a microphone disposed in a control space into a noise signal in a frequency domain, a storage that stores the converted noise signal in the frequency domain as a reference signal, and a signal generator that generates a noise reduction signal for reducing the noise signal collected by the microphone at a control position of the control space. The processor determines whether or not the noise signal is non-stationary noise based on a frequency characteristic of the converted noise signal in the frequency domain and a frequency characteristic of the reference signal. When it is determined that the noise signal is the non-stationary noise, the processor controls the signal generator so as to cancel generation of the noise reduction signal.

Noise reduction device

In a noise reduction device that generates and outputs a control sound signal for reducing noise, an internal loop control unit controls an internal loop in which a pre-output control sound signal that is acquired from a control sound output unit before output to a speaker is input to a sound receiver. A measurement unit measures an input level of a microphone sound signal and an input level of the pre-output control sound signal that has been input to the sound receiver in the internal loop. A fault detector uses the input level of the microphone sound signal and the input level of the pre-output control sound signal measured by the measurement unit to detect a fault in any one of the microphone, the sound receiver, the speaker, and the control sound output unit. A transmitter sends a result of fault detection performed by the fault detector to a management device.

Noise reduction device, noise reduction system, and fault detection method for noise reduction device

A howling removing apparatus according to the present disclosure is a howling removing apparatus to be connected to a microphone and a speaker. The howling removing apparatus includes: a nonlinear converter that nonlinearly converts a sound signal input to the speaker and outputs a nonlinear signal; a delay unit that delays the sound signal by a fixed time and outputs a delay signal; a norm calculator that calculates a norm from the delay signal; a filter coefficient generator that, based on the nonlinear signal, the delay signal and the norm, generates an adaptive filter that simulates a transfer characteristic of a space where the sound signal is reproduced from the speaker and is returned to the microphone; a cancel signal generator that convolves the delay signal and the adaptive filter with each other and generates a cancel signal; and a subtracter that subtracts the cancel signal from the sound signal. When an average sound pressure level of the sound signal exceeds a threshold value, the filter coefficient generator initializes the adaptive filter, thereby sensing oscillation of the adaptive filter even when a positional relationship between the microphone and the speaker is dynamically changed, and returning an output to normal.

Apparatus for removing howling and method for removing howling

An audio signal processing apparatus includes: an obtaining unit which obtains a stereo signal including an R signal and an L signal; a control unit which generates a processed R signal and a processed L signal by performing (i) a first process of convolving pairs of right- and left-ear head related transfer functions into the R signal so that a sound image of the R signal is localized at each of two or more different positions at a right side of a listener; and (ii) a second process of convolving pairs of right- and left-ear head related transfer functions into the L signal so that a sound image of the L signal is localized at each of two or more different positions at a left side of the listener; and an output unit which outputs the processed R signal and the processed L signal.

Audio signal processing apparatus and audio signal processing method

An audio signal reproduction device generates, from an obtained audio signal, first reproduction signals for the first speaker group, sounds from which are localized at first virtual sound positions, and second reproduction signals for the second speaker group, sounds from which are localized at second virtual sound positions substantially the same as the first virtual sound positions. The audio signal reproduction device generates the first reproduction signals and the second reproduction signals so that at least phases or sound pressure values of a first sound and a second sound are different at a listening position, the first sound being indicated by the first reproduction signals, and localized at a first position among the first virtual sound positions, the second sound being indicated by the second reproduction signals, localized at a substantially same position as the first position, and substantially the same as the first sound.

Audio signal reproduction device and audio signal reproduction method

When a correlation between an L channel and an R channel of a reproduction-target sound source is considerably high, virtual sound obtained from a reproduction signal is often more likely to be localized inside the head of a listener. A device includes: a correlation analysis unit () that analyzes a degree of correlation between a surround L channel signal (SL signal) and a surround R channel signal (SR signal); and an output signal control unitthat controls, based on the degree of correlation between the SL signal and the SR signal obtained as a result of the analysis performed by the correlation analysis unit (), a ratio between: the signals outputted from a front L speaker () and a front R speaker (); and the signals outputted from a near-ear L speaker () and a near-ear R speaker ().

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Osaka, Japan

Junji Araki