Yamaha Corporation

Mitsubishi Kagaku Media Co., Ltd.

Morito Morishima

Akira Usui

Takehiko Kawahara

Kiyoshi Yamaki

Atsushi Ishihara

Nobuaki H Tsuji

Yusuke Konagai

Hirotaka Kawai

Takashi Norimatsu

Fujio Matsuishi

Kanji Shimizu

Teruhiko Tsurumi

Takashi Nagano

Yoshihiko Shiozaki

Eiichi Suzuki

Shinji Aoshima

Yohei Otani

Takashi Ubayama

Yuki Ueya

Yukihisa Nakajyo

Yoshihiko Shirosaki

An audio signal generation device () includes: an acquirer () configured to acquire biological information of a human subject; an audio signal generator () configured to generate an audio signal based on at least one of a plurality of pieces of sound information; and a switching cycle decider () configured to decide a switching cycle, such that first sound information switches to second sound information at a cycle that is in accordance with the biological information, the first sound information and the second sound information being included in the plurality of sound information pieces, and the audio signal generator () generates an audio signal based on the second sound information, at the switching cycle decided by the switching cycle decider ().

Audio signal generation device, audio signal generation method, and computer-readable storage medium

An information processing apparatus includes: an estimator configured to estimate, based on biological information of a human subject, a sleep indicator indicative of a depth of sleep of the human subject; and a volume controller configured to control a volume adjuster that generates a second playback sound signal by adjusting an amplitude of a first playback sound signal, such that the first playback sound signal is adjusted based on the sleep indicator and a volume of an ambient sound in an environment in which the human subject is situated.

Sound signal controlling apparatus, sound signal controlling method, and recording medium

Provided is a sleep guidance device that serves to control a stimulus imparter for imparting stimuli to a human subject. The sleep guidance device acquires a biorhythm of the human subject; estimates sleep depths of the human subject from the acquired biorhythm of the human subject; and controls the stimulus imparter to impart a stimulus to the human subject in accordance with the acquired biorhythm of the human subject, and from among the sleep depths, a current sleep depth estimated for the human subject.

Sleep guidance device and control method

A sound generator device includes an acquisition unit configured to acquire biological information on a subject user, an estimation unit configured to estimate, based on the biological information, a mind and body state relating to sleep of the subject user. The sound generator also includes a sound generator configured to output a sound signal based on a plurality of control patterns stored in advance and a sound generator control unit configured to select, based on the estimated mind and body state, at least one control pattern among the plurality of control patterns. The sound generator outputs the sound signal based on the at least one control pattern.

Sound generator device and sound generation method

A driving apparatus includes a power amplifier that supplies a driving signal to a vibrator, a current detector that outputs a detection signal corresponding to a driving current of the vibrator, and a driving controller that positively feedback a signal based on the detection signal to the power amplifier. The driving controller includes an A/D converter that A/D converts the detection signal, a first processing section that applies a gain compensation and compressor processes to an output digital signal of the A/D converter, a second processing section that performs a process of adding a digital signal corresponding to an input signal of the driving apparatus to an output digital signal of the first processing section, and a D/A converter that D/A converts an output digital signal of the second processing section to produce an analog signal supplied to the power amplifier.

Driving apparatus

A method for notifying a motion includes decoding watermark information superimposed on sound or video, outputting timing information obtained as a decoding result, analyzing a motion of a user with reference to a table, determining whether or not a predetermined timing comes based on the timing information, performing determination regarding the motion of the user based on an analysis result if it is determined that the predetermined timing comes, and performing notification based on a result of the determination.

Method and apparatus for notifying motion

An ambient noise removal device includes: a sound signal output section that outputs a sound signal to thereby drive a speaker; a noise detection section that detects an electromotive force produced in the speaker by ambient noise; and a noise cancellation section that generates, on the basis of the electromotive force, a signal of an opposite phase from the ambient noise and adds the generated signal to the sound signal to thereby cancel the ambient noise.

Ambient noise removal device

An amplifier circuit performs a characteristic correction process and a smooth curvilinear process on an input signal before being subjected to amplification. The characteristic correction process is a frequency characteristic process, which is performed on the input signal so as to produce a processed signal (Vp). Either the input signal or the processed signal, or the mixture of these signals is subjected to the smooth curvilinear process whose start point is designated by a state variation of amplification (VxTyp). Alternatively it is subjected to a gain decrement process instead of the smooth curvilinear process when the state variation of amplification is less than a default value (VxTHD). Thus, it is possible to prevent clipping from occurring in the amplified output signal while maintaining an adequate power.

Amplifier circuit utilizing characteristic correction and smooth curvilinear correction

A class D amplifier circuit for generating a pulse signal whose pulse width is modulated in response to an input signal, the class D amplifier circuit includes first to fifth switching elements, a first capacitance element and a control section. The control section controls transition between a conduction state and a non-conduction state of each of the first to fifth switching elements to control a current direction flowing into a load having a first end electrically connected to the output end and a second end set to the reference potential, so that the current flows from the first end of the load to the second end of the load at a first timing and the current flows from the second end of the load to the first end of the load at a second timing.

Class D amplifier circuit

An optical pickup is disposed which irradiates a laser beam onto an optical disc where a guide groove having characteristics of thermal interference (heat discoloration) is spirally formed. The optical pickup irradiates the laser beam along the guide groove to conduct one of data recording in which pits indicating a data length are formed, and visible-image formation in which a part of the optical disc is discolored. The laser beam irradiation position is controlled so that the data recording is conducted with starting from the inner peripheral side of the optical disc, and the visible-image formation is conducted with starting from the outer peripheral side of the optical disc.

Optical disc recording apparatus

A position of a speaker is detected two-dimensionally or three-dimensionally, and a sound field is corrected. A sound reproducing apparatus includes a measuring signal generating portion for generating a first measuring signal, a transmission portion for transmitting a second measuring signal as soon as the first measuring signal is generated, sensors disposed in a listening position and for measuring a time difference between a time instant when the second measuring signal was received and a time instant when a measuring sound wave radiated from a to-be-detected speaker in accordance with the first measuring signal was received, and a position calculating portion for calculating a distance, as to each ofsensors, between each of thesensors and the to-be-detected speaker based on the measured time difference, and calculating the position of the to-be-detected speaker based on distances among thesensors and the calculated distance.

Sound reproducing apparatus and method of identifying positions of speakers

The present invention provides a D/A converter circuit which enables D/A conversion with a high precision and can prevent occurrence of a limit cycle component in the case where an input signal is low, and can also prevent the effect of dither signal from occurring in an analog signal which is a D/A conversion result. A dither signal generation sectionoutputs a dither signal (DITHER) which is an alternating current signal and a reversal dither signal (DITHER_N) inverted from the dither signal. A DEM decoderprocesses an input digital signal including a component of the dither signal (DITHER), and outputs a plurality of lines of time-series digital signals having a density of '1' or '0' conforming to the input digital signal to be processed. An analog addition sectionconverts a plurality of lines of time-series digital signals and the reversal dither signal (DITHER_N) into an analog signal respectively and adds them, and outputs an analog signal which is a D/A conversion result.

D/A converter circuit and digital input class-D amplifier

An optical disk apparatus is constructed for writing or reading information by irradiating a laser beam onto an optical disk while rotating the optical disk under a focus control of the laser beam relative to the rotated optical disk. In the optical disk apparatus, an irradiating section is operated to irradiate a laser beam onto the optical disk. A determining section determines a process pattern of the focus control by operating the irradiating section to irradiate the laser beam onto a predetermined area of the optical disk and by monitoring the laser beam reflected back from the predetermined area. A focusing section performs the focus control to regulate a spot diameter of the laser beam based on the determined process pattern during either of the writing or reading of information.

Optical disk apparatus with approximate focus control of laser beam

A signal generating apparatus includes: a data generator which generates a data series in which first, second, third and fourth data are arranged at a sampling period; a first signal generator which generates a first pulse-width modulation signal in which a pulse is arranged in a pulse period longer than the sampling period, time points of front and rear edges of the pulse being set in response to the first and second data; and a second signal generator which generates a second pulse-width modulation signal in which a pulse is arranged between the adjacent pulses of the first pulse-width modulation signal, time points of front and rear edges of the pulse of the second pulse-width modulation signal been set in response to the third and fourth data, respectively.

Signal generating apparatus and class-D amplifying apparatus

A time period control unit controls a time length 'TU' of each of unit terms 'U' in a variable manner. A pulse-width modulating unit is arranged by a holding unit, a counting unit, and a waveform generating unit. The holding unit holds thereinto a plurality of data &#x201c;XD&#x201d; every unit term &#x201c;U&#x201d;, which are sequentially supplied, as data &#x201c;XE.&#x201d; The counting unit changes a count value &#x201c;X&#x201d; during each of the unit terms &#x201c;U.&#x201d; The waveform generating unit generates such a pulse-width modulating signal &#x201c;S&#x201d; that pulses &#x201c;P&#x201d; have been arranged every unit term &#x201c;U&#x201d;, while time points when a large/small relationship between the count value &#x201c;C&#x201d; and a numeral value of the data &#x201c;XE&#x201d; held by the holding unit is inverted are defined as edge portions of the pulses.

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Fukuroi, Japan

Morito Morishima