Abstract: A quality level analysis unit 504 specifies a coding method, communication line conditions, and a quality level, such as an S/N ratio and the like, of voices of an input channel, received by a corresponding receiving unit 501. A channel allocation/mixing unit 502 controls the allocation or mixing of voices of respective input channels to or into respective output channels 503 (output units 505) on the basis of the results of analysis by the quality level analysis unit 504. Consequently, loud speakers from which poor quality voices and good quality voices are output can be separated from one another, thus improving the total intelligibility of received voices.

Abstract: As optimal candidate as a control signal (y*) for generating a control sound suppressing noise from a speaker is selected from among a plurality of control signal candidates (y1 to yn) by a selection function unit. For this selection, a residual noise estimation function unit receiving as input a residual noise signal (e) from an error microphone is introduced. The function unit first obtains an estimated value of a noise component using a first transfer characteristic simulating filter. Further, this noise component estimated value and filtered outputs from second transfer characteristic simulating filters are used to obtain residual noise estimated values for the control signal candidates (y1 to yn). Further, the single control signal candidate corresponding to the smallest of these residual noise estimated values is selected and used as the above control signal (y*).

Abstract: A sleep apnea syndrome testing apparatus includes: an analyzing unit that analyzes every unit time a sound signal resulting from a subject during sleep; a determining unit that determines whether a unit time of the sound signal includes a breath sound or a characteristic sound produced when a patient with sleep apnea syndrome recovers from an apneic state into a breathing state, and the determining unit that determines that the sleep state of the subject in the unit time is any one of “breathing restored state,” “state with breathing,” and “state without breathing;” a storage unit in which a sleep state of the subject in each unit time is stored; and a detecting unit that detects an apneic state of the subject if a history of the sleep states of the subject indicates at least a transition from the “state without breathing” to the “breathing restored state.

Abstract: A voice communication apparatus includes an analysis unit to analyze an outgoing conversation signal transmitted from a user of the voice communication apparatus to another party in communication or an incoming conversation signal from the another party in communication received by the voice communication apparatus, a storage unit to store a voice message to be played back, a mixing unit to perform mixing of the voice message with the incoming conversation signal, and a control unit to control a start timing of the mixing so that the mixing of the voice message with the incoming conversation signal is started between utterances of the user on the basis of an analysis result of the analysis unit.

Abstract: In an echo processing method and device which can detect an accurate echo section without effects of a far end signal, an echo delay, and a reduction of an echo cancellation amount, a signal of a specified frequency band is generated in conformity with a near end signal, and the signal of the specified frequency band is added to the near end signal to form a transmitting signal. Receiving signals are separated into the signal of the specified frequency band and a signal of a band other than the specified frequency band. An echo section is detected based on the signal of the specified frequency band separated. An echo component in the signal of the band other than the specified frequency band is removed and a level of the echo component is detected based on the near end signal in the echo section.

Abstract: A voice reproduction apparatus includes an ambient sound analysis unit to analyze a characteristic of an ambient sound, a characteristic analysis unit to analyze an acoustic characteristic of a signal for reproduction, a reproduction timing adjusting unit to record the signal for reproduction and to read the signal for reproduction at a reproduction timing of follow-up reproduction, a reproduction speed changing unit to change a reproduction speed of the read signal for reproduction, and a control unit to control the reproduction timing adjusting unit so that the signal for reproduction is reproduced at the reproduction timing corresponding to an analysis result of the ambient sound analysis unit and to control the reproduction speed changing unit so that the signal for reproduction is reproduced at the reproduction speed corresponding to the analysis result of the ambient sound analysis unit and the acoustic characteristic obtained by the characteristic analysis unit.

Abstract: An active silencer includes: a speaker generating control sound which interferes with noise; a microphone detecting noise remaining after the interference as a remaining noise signal; a sound quality evaluation unit evaluating the sound quality of the remaining noise and output a result of the sound quality evaluation; an actuation signal determination unit determining, according to the result of the sound quality evaluation, the detection timing of the frequency component of the remaining noise signal to be used when the control sound is generated for a plurality of bands of the remaining noise, corresponding to the plurality of bands of a reference signal corresponding to the noise; and a control signal generation unit generating and output a control signal for generation of the control sound depending on a plurality of bands of the determined remaining noise signal and a plurality of bands of the reference signal corresponding to the noise.

Abstract: An audio signal processing system including a time-frequency conversion unit which converts an audio signal in time domain into frequency domain in frame units so as to calculate a frequency spectrum of the audio signal, a spectral change calculation unit which calculates an amount of change between a frequency spectrum of a first frame and a frequency spectrum of a second frame before the first frame based on the frequency spectrum of the first frame and the frequency spectrum of the second frame, and a judgment unit which judges the type of the noise which is included in the audio signal of the first frame in accordance with the amount of spectral change.

Abstract: An active noise control apparatus that controls by a control sound a noise which is output from a noise source, includes: a control sound generating section which inputs a control signal, and produce the control sound; a residual noise detecting section which detects, as a residual noise signal, a noise remaining after the noise control by the control sound; a control signal generating section which inputs, as a reference signal, a signal concerning the noise or the generation state of the noise, and generates the control signal; and a controlling section which inputs the control signal and the residual noise signal, detects the components that cannot be identified in the control signal generating section, and controls the generation of the control signal in the control signal generating section.

Abstract: An optical device includes a fast Fourier transform (FFT) unit, a signal noise ratio (SNR) calculation processing unit, a band selecting unit, an extension-signal creating unit, an addition unit, and an inverse fast Fourier transform (IFFT) unit. The FFT unit performs the Fourier transform on an input signal that is input from the outside. The SNR calculation processing unit calculates an SNR with respect to each of bands in the input signal. The band selecting unit selects a band of which SNR exceeds a threshold and is the maximum SNR, based on respective SNRs of the bands. The extension-signal creating unit creates an extension signal based on a signal acquired by the band selecting unit. The addition unit adds the extension signal to the input signal, and creates a band-extended signal. The IFFT unit performs the inverse fast Fourier transform on the band-extended signal, and creates an output signal.

Abstract: A communication apparatus includes an image capturing unit configured to capture a face image of a user; a contour extraction unit configured to extract a face contour from the face image captured by the image capturing unit; an ear position estimation unit configured to estimate positions of ears of the user on the basis of the extracted face contour; a distance estimation unit configured to estimate a distance between the communication apparatus and the user on the basis of the extracted face contour; a sound output unit configured to output sound having a directivity; and a control unit configured to control an output range of sound output from the sound output unit on the basis of the positions of ears of the user estimated by the ear position estimation unit and the distance between the communication apparatus and the user estimated by the distance estimation unit.

Abstract: A data embedding device for embedding data in a speech code obtained by encoding a speech in accordance with a speech encoding method based on a voice generation process of a human being, includes an embedding judgment unit, every speech code, judging whether or not data should be embedded in the speech code, and an embedding unit embedding data in two or more parameter codes of a plurality of parameter codes constituting the speech code for which it is judged by the embedding judgment unit that the data should be embedded.

Abstract: A data decryption apparatus that decrypts encrypted data, includes a first data-receiving unit that receives a first data set, in which information on an encryption specification is embedded, through a first communication path; a time-information obtaining unit that obtains time information on a reception of the first data set by the first data receiving unit; a time-information storage unit that stores the time information with the information on the encryption specification associated therewith; a second data-receiving unit that receives a second data set through a second communication path, the second data set being encrypted based on the encryption-specification and appended by time information on performing data encryption; and an encryption-specification selecting unit that selects an encryption specification for use in decryption of the second data set based on the time information stored in the time-information storage unit and the time information appended to the second data set.

Abstract: In an apnea detecting apparatus, a respiratory pace analyzer determines a respiratory pace of a user based on an ambient noise (including a breathing sound, a snore, and the like of the user) generated in a surrounding area and on information of a posture of the user in determining whether or not the user suffers from the apnea syndrome. Then, an apnea time extracting unit in the apnea detecting apparatus determines whether or not a silent time is included in a time period during which the user is estimated to be breathing based on the respiratory pace and the silent time in the ambient noise.

Abstract: A data embedding device for embedding data in a speech code obtained by encoding a speech in accordance with a speech encoding method based on a voice generation process of a human being, includes an embedding judgment unit, every speech code, judging whether or not data should be embedded in the speech code, and an embedding unit embedding data in two or more parameter codes of a plurality of parameter codes constituting the speech code for which it is judged by the embedding judgment unit that the data should be embedded.

Abstract: Communications from a transmission side to a reception side neither changing the format of voice code data nor requiring another transmission path or increasing the transmission quantity of control information are controlled utilizing information obtained on the reception side. A system includes a first communication equipment provided with a control information embedding unit for embedding control information that is used for a control of communications from a communication partner to the own communication equipment and that is obtained on the own communication equipment side in the communication data to be transmitted to the communication partner side and a second communication equipment provided with a communication control unit for controlling communications to the first communication equipment side using control information transmitted from the first communication equipment.

Abstract: In a pitch conversion method and device which can reduce data throughput while suppressing a degradation of sound quality due to a pitch conversion as much as possible, an input signal pitch pattern per predetermined processing unit and a target pitch pattern are inputted, and a degradation degree indicating how a waveform of the input signal degrades upon pitch conversion from the input signal pitch pattern to the target pitch pattern is calculated. Alternatively, a degradation degree corresponding to a voice state and a phonemic type of the input signal is extracted from a database in which all of combinations of voice states and phonemic types estimated are associated with the degradation degrees to be recorded. Then, a pitch converter which performs a pitch conversion with small data throughput and a pitch converter which performs a pitch conversion with large data throughput are switched over depending on the degradation degree.

Abstract: A voice band expansion device includes a time-frequency converter that calculates a frequency spectrum of a voice signal having a first frequency band; a separator that extracts, from the frequency spectrum, an envelope amplitude spectrum, a periodic amplitude spectrum, and a random amplitude spectrum; an envelope amplitude spectrum band expander that expands a frequency band to a second frequency band that is different from the first frequency band; a periodic amplitude spectrum band expander that expands a frequency band to the second frequency band; a random amplitude spectrum band expander that expands a frequency band of the random amplitude spectrum to the second frequency band; a broadband spectrum calculator that calculates a broadband frequency spectrum having the first frequency band and the second frequency band; and a frequency-time converter generates a voice signal having the first frequency band and the second frequency band.

Abstract: In a wireless communication apparatus, an ambient apparatus number measurement unit measures the number of wireless apparatuses existing around. A movement amount measurement unit detects acceleration at the time when its own apparatus moves and measures the movement amount of its own apparatus. An ambient sound analysis unit records ambient sounds and analyzes the recorded ambient sounds to generate ambient sound analysis information. A communication controller estimates surroundings of its own apparatus based on at least one of the number of the measured wireless apparatuses, the measured movement amount, and the ambient sound analysis information, and autonomously performs a communication control of its own apparatus according to the estimated surroundings.

Abstract: In a packet receiving method and device which convert a voice packet received into a voice, a receiving packet buffer temporarily stores a voice packet received; a plurality of parameter information monitors respectively determine different buffer adjustment values for determining a buffering amount of the receiving packet buffer based on one or more pieces of parameter information obtained from the voice packet temporarily stored; a buffer adjustment value determiner determines a receiving buffer adjustment value from the plural buffer adjustment values; and a buffer controller controls the buffering amount based on the receiving buffer adjustment value.