Clarion Co

Tetsuo Watanabe

Takeshi Hashimoto

Yasuhiro Fujita

Kazutomo Fukue

Takatomi Kumagai

Kenji Kono

Hideyuki Morita

Toshihiro Fueki

Provided is a notification device and notification method that reduce the output and power consumption of an amplifier or the like and allow a user to sufficiently feel the presence or absence of notification through vibration. A notification device () includes a sweep signal generator () configured to generate a detection sweep signal by continuously changing the frequency in a frequency band in which a speaker () can cause a user to feel a signal in the form of vibration, a vibration detector () configured to detect vibration outputted from the speaker (), and a sound measurement unit () configured to detect, as a sweep frequency band, a frequency band in which vibration indicates signal levels equal to or higher than a threshold. The sweep signal generator () generates a resonance sweep signal by changing the frequency in the sweep frequency band and causes the speaker () to generate vibration.

Notification device and notification method

An audio processor () includes a first filter coefficient calculator () that calculates a first filter coefficient so as to correspond to first gains for respective bands set by a user, a second filter coefficient calculator () that if values of third gains for respective bands of the first filter coefficient are greater than an absolute value of a second gain set by the user, calculates a second filter coefficient by limiting the values of the third gains for the respective bands to the amplitude value of the second gain, and a filtering unit () that filters an audio signal that has been transformed into a frequency-domain signal, using the second filter coefficient.

Audio processor and audio processing method

A propagation delay tune correction apparatus comprising a means for generating a frequency spectrum signal by performing short-term Fourier transform on an audio signal; a means for setting a propagation delay time for each of a plurality of predetermined frequency bands; a means for calculating a phase control amount for each of the plurality of predetermined frequency bands on a basis of the propagation delay time set for each of the plurality of predetermined frequency bands; a means for generating a phase control signal by smoothing the calculated phase control amount for each of the plurality of predetermined frequency bands; a means for controlling a phase of the frequency spectrum signal for each of the plurality of predetermined frequency bands on a basis of the generated phase control signal; and a means for generating an audio signal on which a propagation delay correction is performed by performing inverse short-term Fourier transform on the frequency spectrum signal of which the phase is controlled for each of the plurality of predetermined frequency bands.

Propagation delay correction apparatus and propagation delay correction method

A phase control signal generation device generating a phase control signal for each of frequency bands for an audio signal converted into a frequency domain, the phase control signal generation device comprising: a setting change means that is able to change setting of a propagation delay time for each of predetermined frequency bands; a difference obtaining means that obtains a difference between propagation delay times before and after setting change; an updating means that updates a phase control amount of the frequency band for which the propagation delay time is changed, based on the obtained difference; and a phase control signal generating means that generates a phase control signal of each frequency band by performing a smoothing process for the phase control amount in a frequency domain using the updated phase control amount.

Phase control signal generation device, phase control signal generation method, and phase control signal generation program

There is provided a signal processing device, comprising: a frequency detecting means that detects a frequency satisfying a predetermined condition from an audio signal; an offset means that gives an offset to the detected frequency by the frequency detecting means in accordance with a frequency property at the detected frequency or around the detected frequency; a reference signal generating means that generates a reference signal by extracting a signal from the audio signal based on the detected frequency offset by the offset means; an interpolation signal generating means that generates an interpolation signal based on the generated reference signal; and a signal synthesizing means that performs high band interpolation by synthesizing the generated interpolation signal and the audio signal.

Signal processing device and signal processing method for interpolating a high band component of an audio signal

A sound-field correction device, comprising: a target calculating unit, a correction amplitude characteristic calculating unit and a setting unit. The target calculating unit calculates, based on a predetermined sound signal, a target amplitude characteristic targeted for sound-field correction by a parametric equalizer and a plurality of auxiliary target amplitude characteristics having amplitude characteristics approximately equal to or gentler than the target amplitude characteristic. The correction amplitude characteristic calculating unit calculates a correction amplitude characteristic for correction sound-field based on the calculated target amplitude characteristic and the calculated plurality of auxiliary target amplitude characteristics. The setting unit sets the parametric equalizer based on the calculated correction amplitude characteristic.

Sound-field correction device, sound-field correction method, and sound-field correction program

A signal processing device comprises: a band detecting means for detecting a frequency band which satisfies a predetermined condition from an audio signal; a reference signal generating means for generating a reference signal in accordance with a detection band by the band detecting means; a reference signal correcting means for correcting the generated reference signal on the basis of a frequency characteristic thereof; a frequency band extending means for extending the corrected reference signal up to a frequency band higher than the detection band; an interpolation signal generating means for generating an interpolation signal by weighting each frequency component within the extended frequency band in accordance with a frequency characteristic of the audio signal; and a signal synthesizing means for synthesizing the generated interpolation signal with the audio signal.

Signal processing device and signal processing method

A notification device () includes a sweep signal generator () that generates a sweep signal by changing the frequency of a predetermined wave at a constant speed in a frequency band which allows exciters (EX, EX, EX, EX) to generate a vibration, a sweep signal divider () that divides the sweep signal into a higher-band sweep signal in a higher-frequency band including an overlap frequency band and a lower-band sweep signal in a lower-frequency band including the overlap frequency band, a signal output determination unit () that determines from which exciters the higher-band sweep signal and lower-band sweep signal should be outputted, and an output signal adjuster () that makes an adjustment for outputting the higher-band sweep signal and lower-band sweep signal from the exciters determined.

A filter generator () generates a filter on the basis of band information (frequency) and gain characteristics (gain value) set by a user. The filter generator () obtains weighting factor information on the basis of the band information selected by the user and calculates a gain difference between a gain value used in a preceding filtering process and the new gain value selected by the user. The filter generator () then obtains a correction gain by multiplying the weighting factor information by the gain difference and generates a filter by multiplying a coefficient of the filter used in the preceding filtering process by the correction gain.

Filter generator, filter generation method, and filter generation program

An acoustic processing device comprises: a resonant band detecting means that detects a resonant band of sound output from a speaker based on a measurement result of a predetermined measurement signal reproduced through the speaker; an analyzing means that analyzes the measurement result of the predetermined measurement signal; a control parameter generating means that generates a control parameter for controlling the resonant band detected by the resonant band detecting means based on an analysis result by the analyzing means; and an audio signal controlling means that controls an audio signal input from a predetermined audio signal reproducing device based on the control parameter generated by the control parameter generating means such that a resonant band component of reproduced sound of the audio signal is suppressed to be short on a time axis.

Acoustic processing device, acoustic processing method, and acoustic processing program

A sound field measuring device () obtains frequency characteristics by collecting output sound outputted from a pair of speakers () installed at a narrow interval. A low-pass filter () extracts low-range components of a first measurement signal. A high-pass filter () extracts mid/high-range components of a second measurement signal different from the first measurement signal. A combined signal generation unit () generates a combined signal by combining the low-range components of the first measurement signal and the mid/high-range components of the second measurement signal. An external output unit () outputs the first measurement signal to an audio system (). A microphone () collects the first measurement signal and the combined signal simultaneously outputted from the pair of speakers. A Fourier transform unit () obtains the frequency characteristics of a sound field by Fourier transforming the signals collected.

Sound field measuring device, method and program

The present invention provides a vibration audio system for transmitting an audio signal outputted from a sound source to a listener in the form of vibration while reducing output level of the signal and power consumption. The system includes an envelope detection unit () for detecting an envelope signal of the audio signal outputted from a sound source, a vibration transmission member for allowing the listener to perceive vibration of a low-frequency sound outputted from a low-frequency output speaker that outputs audio signals, and a frequency conversion unit () for generating an audio signal frequency-converted on the basis of resonant frequencies by multiplying the envelope signal by sine waves having the same frequencies as resonance frequencies obtained from an impulse response of the low-frequency output speaker disposed in the vibration transmission member. The audio signal frequency-converted by the frequency conversion unit () is outputted from the low-frequency output speaker.

Vibration audio system, vibration audio output method, and vibration audio program

A sound field measuring device () includes an external output unit () configured to output a measurement signal composed of a periodic function having a code length of 2&#x2212;1 (n is a natural number) to a speaker (), a microphone () configured to pick up the measurement signal outputted from the speaker (), a Fourier transform unit () configured to obtain frequency characteristics by Fourier transforming measurement sound picked up with a sample length of 2(m is a natural number), a thinning-out unit () configured to remove line spectra except for the (k&#xd7;2+1)th line spectra (k=0, 1, 2, and the like) from the obtained frequency characteristics, and an averaging unit () configured to obtain averaged frequency characteristics of a sound field on the basis of frequency characteristics thinned-out.

Sound field measuring device, method, and program

Provided is an acoustic signal processing device for producing an output sound meeting listener's preferences by adjusting attack sound, reverberation, and noise component. The device includes: an FFT section for transforming an input audio signal from a time-domain to a frequency-domain to calculate a frequency spectrum signal and for generating a first amplitude spectrum signal and a phase spectrum signal; an attack component controller () for controlling an attack component of the first amplitude spectrum signal to generate a second amplitude spectrum signal; a reverberation component controller () for controlling a reverberation component of the first amplitude spectrum signal to generate a third amplitude spectrum signal; a first adding section () for synthesizing the first amplitude spectrum signal, the second amplitude spectrum signal, and the third amplitude spectrum signal to generate a fourth amplitude spectrum signal; and an IFFT section for generating an audio signal transformed from a frequency domain to a time domain based on the fourth amplitude spectrum signal and the phase spectrum signal generated by the FFT section.

Acoustic signal processing device and acoustic signal processing method

A direct sound extraction device includes: a spectrum transform unit that transforms an input signal, which includes a reverberant sound in a direct sound and on which a Fourier transform process has been performed, to a first amplitude spectrum signal Lfa; a low-pass filter unit () that performs a low-pass filtering process on the first amplitude spectrum signal Lfa for each frequency to generate a second amplitude spectrum signal Lfa; a first subtraction unit () that calculates a third amplitude spectrum signal by subtracting the second amplitude spectrum signal Lfafrom the first amplitude spectrum signal Lfa; and an inverse Fourier transform unit that generates a direct sound signal Lfd from a frequency spectrum signal calculated based on a phase spectrum signal and the third amplitude spectrum signal.

Growing community of inventors

Hasuda, Japan

Tetsuo Watanabe