Abstract: A sound emission and collection device includes a speaker, a filter processing a sound emission signal, microphones, echo cancellers cancelling regression sound signals of the sound emitted by the speaker from the sound collection signals of the corresponding microphones, a first integration section integrating adaptive filter coefficients taken out from the plurality of echo cancellers, a reverberation time estimation section estimating the reverberation time for each frequency band in the space in which the speaker and the plurality of microphones are present on the basis of the integrated adaptive filter coefficient, and an arithmetic operation section specifying a frequency band having a long reverberation time from the sound emission signal based on the estimated reverberation time, calculating a filter coefficient for suppressing power of the specified frequency band, and setting the filter coefficient to the filter.

Abstract: A sound emission and collection device includes a speaker, a filter processing a sound emission signal, microphones, echo cancellers cancelling regression sound signals of the sound emitted by the speaker from the sound collection signals of the corresponding microphones, a first integration section integrating adaptive filter coefficients taken out from the plurality of echo cancellers, a reverberation time estimation section estimating the reverberation time for each frequency band in the space in which the speaker and the plurality of microphones are present on the basis of the integrated adaptive filter coefficient, and an arithmetic operation section specifying a frequency band having a long reverberation time from the sound emission signal based on the estimated reverberation time, calculating a filter coefficient for suppressing power of the specified frequency band, and setting the filter coefficient to the filter.

Abstract: A sound emission and collection device includes a speaker, a filter processing a sound emission signal, microphones, echo cancellers cancelling regression sound signals of the sound emitted by the speaker from the sound collection signals of the corresponding microphones, a first integration section integrating adaptive filter coefficients taken out from the plurality of echo cancellers, a reverberation time estimation section estimating the reverberation time for each frequency band in the space in which the speaker and the plurality of microphones are present on the basis of the integrated adaptive filter coefficient, and an arithmetic operation section specifying a frequency band having a long reverberation time from the sound emission signal based on the estimated reverberation time, calculating a filter coefficient for suppressing power of the specified frequency band, and setting the filter coefficient to the filter.

Abstract: A sound pickup apparatus, which can control directionality and has a simple structure, and in which a plurality of microphones can be provided so as to be floated by using the small number of parts, is provided. Three support columns 13A to 13C having the same length are provided upright on a top surface of a housing 11 of a sound pickup apparatus 1. The support columns 13A to 13C are equidistantly arranged away from a center position of the housing 11 and equally spaced 120 degrees apart from each other. A frame 4 having microphone frames 14A to 14C in which microphones are fitted is arranged above the top surface of the housing 11. In addition, the microphone frames 14A to 14C are coupled to the support columns 13A to 13C of the housing 11 by elastic rubbers 15A to 15C in a state where tensile stress passes the center of the housing 11 and is generated in an outward direction.

Abstract: The invention provides a sound collection device having little error in a desired directivity. The sound collection device includes a unidirectional microphone 12A, a unidirectional microphone 12B, and a unidirectional microphone 12C which are arranged on one plane. Each of the unidirectional microphones has the maximum sensitivity direction directed toward the inside of the arrangement. Each of the unidirectional microphones has a rear surface (direction of the minimum sensitivity) being open acoustically. Since the maximum sensitivity direction of each of the unidirectional microphones is directed toward the inside of the arrangement, the oscillation plane of each of the unidirectional microphones can be positioned substantially at the center of the arrangement. Thus, by adjusting the gain of the sound collected by the respective unidirectional microphones, the directivity can be freely formed on a flat plane with little error.

Abstract: A first calculating portion calculates a model sound index value which is an index value of the maximum value of power for each frequency band of the model sound which is a model of a target sound. A second calculating portion calculates a source sound index value which is an index value of power for each frequency band with respect to each of frames extracted by a predetermined time length from a source sound signal. A third calculating portion calculates a performance index value indicating performance of masking the model sound by a sound represented by a block formed of a predetermined number of consecutive frames extracted from the source sound signal, by using the model sound index value and the source sound index value. A frame selecting portion determines a block to be used for generating the masker sound based on the performance index value.

Abstract: A sound emitting and collecting apparatus that can accomplish stable echo removal if the relative positions of a loudspeaker and a microphone change is provided. A control section 52 inputs information of an arm rotation angle from a sensor 54. The control section 52 reads the filter coefficient corresponding to the input rotation angle from memory 53 and sets the coefficient in an adaptive filter 412A. When the arm rotates, the installing position of a microphone is changed and an acoustic transmission system changes, but a preset (or in the installing environment, updated) filter coefficient is set, whereby stable echo removal can be accomplished.

Abstract: An acoustic apparatus without increasing noise etc. even when plural directional microphones collect sounds from a place of the same distances is provided. Sound signals output from the microphone arrays are subjected to phase shift by phase shift circuits 211A to 211H, and the sound signals are combined by an adder 212. The phase shift circuits 211A to 211H performs phase shifts according to installation positions of the microphone arrays. The phase shift circuit 211A makes the shift 0 degree, the phase shift circuit 211B makes the shift 45 degrees, the phase shift circuit 211C makes the shift 90 degrees, and sequentially to the phase shift circuit 211H, the shifts are made according to rotational angles.

Abstract: A voice emitting and collecting device that is capable of picking up/outputting a voice emitted from a talker at a high S/N ratio by eliminating the influence of a diffracting voice despite a simple configuration is provided. A signal differencing circuit 191 outputs difference signals MS1 to MS4 between voice collecting beam signals MB11 to MB14 and voice collecting beam signals MB21 to MB24. A level comparator 195 selects the difference signal having a maximum level. A signal selecting circuit 196 selects voice collecting beam signals MB1x, MB2x of the difference signal MS that is selected/pointed by the level comparator 195. A subtracter 199 subtracts the voice collecting beam signal MB2x from the voice collecting beam signal MB1x, and output a resultant signal. Accordingly, main components of the diffracting voice can be removed from the voice collecting beam signal.

Abstract: A level ratio calculation circuit calculates average signal level data of signal level data corresponding to each sound collection beam signal, and calculates a level ratio between the average signal level data and each of the signal level data. Since a diffraction sound is substantially equal to all the signal level data, a diffraction sound component of the average signal level data also becomes substantially equal. On the other hand, a collection sound from a speaker is specific to the signal level data of the corresponding sound collection beam signal. Therefore, at the level ratio, the portion corresponding to the diffraction sound is flat and a data level becomes high locally in only the portion corresponding to the collection sound. By using this, the sound collection beam signal including the collection sound is detected.

Abstract: Microphone arrays, which are formed by arranging a plurality of microphones, are provided on a front side and a rear side of a housing, respectively. A virtual focus is set for each of the microphone arrays in a direction opposite to a direction in which sound is picked-up sound signals picked up by the plurality of microphones are delayed such that distances to the virtual focus are the same, and the delayed sound signals are synthesized. Therefore, sound in a sound-pickup area of a predetermined angle on each of the front side and the rear side can be picked up at a high level, and even though there is a noise source in areas other than the sound-pickup area, noise from the noise source is not picked up.

Abstract: A speaker array and microphone arrays positioned on both sides of the speaker array are provided. A plurality of focal points each serving as a position of a talker are set in front of the microphone arrays respectively symmetrically with respect to a centerline of the speaker array, and a bundle of sound collecting beams is output toward the focal points. Difference values between sound collecting beams directed toward the focal points that are symmetrical with respect to the centerline are calculated to cancel sound components that detour from the speaker array to microphones. Then, it is estimated based on totals of squares of peak values of the difference values for a particular time period that the position of the talker is close to which one of the focal points, and the position of the talker is decided by comparing the totals of the squares of the peak values of the sound collecting beams directed to the focal points that are symmetrical mutually.

Abstract: The invention provides a sound collection device having little error in a desired directivity. The sound collection device includes a unidirectional microphone 12A, a unidirectional microphone 12B, and a unidirectional microphone 12C which are arranged on one plane. Each of the unidirectional microphones has the maximum sensitivity direction directed toward the inside of the arrangement. Each of the unidirectional microphones has a rear surface (direction of the minimum sensitivity) being open acoustically. Since the maximum sensitivity direction of each of the unidirectional microphones is directed toward the inside of the arrangement, the oscillation plane of each of the unidirectional microphones can be positioned substantially at the center of the arrangement. Thus, by adjusting the gain of the sound collected by the respective unidirectional microphones, the directivity can be freely formed on a flat plane with little error.

Abstract: A sound pickup apparatus, which can control directionality and has a simple structure, and in which a plurality of microphones can be provided so as to be floated by using the small number of parts, is provided. Three support columns 13A to 13C having the same length are provided upright on a top surface of a housing 11 of a sound pickup apparatus 1. The support columns 13A to 13C are equidistantly arranged away from a center position of the housing 11 and equally spaced 120 degrees apart from each other. A frame 4 having microphone frames 14A to 14C in which microphones are fitted is arranged above the top surface of the housing 11. In addition, the microphone frames 14A to 14C are coupled to the support columns 13A to 13C of the housing 11 by elastic rubbers 15A to 15C in a state where tensile stress passes the center of the housing 11 and is generated in an outward direction.

Abstract: A sound emission and collection device includes a main housing and two sub-housings. In the main housing, a microphone array is provided. Microphone arrays are also provided in the sub-housings. Sound collection directions of the microphone arrays are outer directions which are opposite a side of the main housing. The sub-housings are rotatably connected to the main housing. The sound emission and collection device generates a plurality of collected sound beam signals MB10 to MB12 based on a collected sound of each of the microphone arrays according to the rotation amounts of the sub-housings with respect to the main housing and performs phase control and addition processing.

Abstract: A sound emitting and collecting apparatus that can precisely detect the talker direction based on a collected sound signal even when a sound is emitted from a loudspeaker is provided. Microphone units MU1 to MU8 collect a sound in sound collecting areas MA1 to MA8 formed so as to have rotational symmetry with the placement position of loudspeakers SP1 and SP2 as the center and generate composite signals SA1 to SA8 (hereinafter, SAk). Logarithm calculation sections L1 to L8 calculate logarithm values Pk of power level of the composite signals SAk. An amplification section 11 calculates a power level average value AV from the logarithm values Pk of power levels and a subtraction section subtracts the power level average value AV from the logarithm values Pk of power level to generate differential signal levels Dk. A maximum value detection section 12 compares differential signal levels Dk and detects the maximum value.

Abstract: A sound emitting and collecting apparatus that can accomplish stable echo removal if the relative positions of a loudspeaker and a microphone change is provided. A control section 52 inputs information of an arm rotation angle from a sensor 54. The control section 52 reads the filter coefficient corresponding to the input rotation angle from memory 53 and sets the coefficient in an adaptive filter 412A. When the arm rotates, the installing position of a microphone is changed and an acoustic transmission system changes, but a preset (or in the installing environment, updated) filter coefficient is set, whereby stable echo removal can be accomplished.

Abstract: An acoustic apparatus without increasing noise etc. even when plural directional microphones collect sounds from a place of the same distances is provided. Sound signals output from the microphone arrays are subjected to phase shift by phase shift circuits 211A to 211H, and the sound signals are combined by an adder 212, The phase shift circuits 211A to 211H performs phase shifts according to installation positions of the microphone arrays. The phase shift circuit 211A makes the shift 0 degree, the phase shift circuit 211B makes the shift 45 degrees, the phase shift circuit 211C makes the shift 90 degrees, and sequentially to the phase shift circuit 211H, the shifts are made according to rotational angles.

Abstract: To provide an audio conference apparatus and an audio conference system which can smoothly proceed with the audio conference by removing a recursion sound of the conference voice is achieved. An audio conference apparatus 1 outputs ring tones from corresponding channels before a communication control unit 12 outputs audio signals from the unused channels (S1 to S3). Speakers SP1 to SP16 emits the ring tone from predetermined sound source positions corresponding to the respective channels. Microphones MIC1A to MIC16A and microphones MIC1B to MIC16B collect audio signals including a recursion sound of the ring tone. The echo cancel unit 20 generates a pseudo-recursion sound signal on the basis of an input signal, and subtracts the pseudo-recursion sound signal from the collected audio signals. An audio conference system is configured to connect a plurality of the audio conference apparatuses to each other.

Abstract: A audio conference device capable of detecting a talker's direction exactly and collecting a sound emitted from this direction at a high signal S/N ratio is provided. A detecting beam generating portion 811 applies a delay-sum process to sound collecting signal SS104 to SS113 of microphones MIC104 to MIC113 that are aligned densely in a center portion in the alignment direction, and generates detecting sound collecting beam signals MB101 to MB114. A outputting beam generating portion 812 applies a delay-sum process to sound collecting signals SS101 to SS116 of all microphones MIC101 to MIC116 that are aligned in the alignment direction to generate outputting collecting beam signals MB101? to MB114?. A sound collecting beam selecting portion 19 detects direction data MS corresponding to a sound collecting beam signal, which has the highest signal density, out of the detecting sound collecting beam signals MB101 to MB114, and feeds the sound collecting beam signal to an outputting beam selecting portion 813.