Abstract: A howling detection device capable of detecting the occurrence of howling with a higher degree of accuracy is provided. The howling detection device includes a signal level calculating unit calculating, from the input signal, an input signal level being the signal level of an input signal at each given time, a level fluctuation estimated value calculating unit calculating, from the input signal level, a level fluctuation estimated value being a value gradually increasing or decreasing by a given amount with time, a threshold value calculating unit calculating, from the level fluctuation estimated value, a level threshold value changing in accordance with the level fluctuation estimated value, and a howling determination unit which determines that howling occurs in an input signal under the condition that the input signal level being higher than the level threshold value continues for a given time.

Abstract: A howling suppression device includes a subtractor which subtracts a pseudo feedback signal from an input signal; an adaptive filter which produces a pseudo feedback signal for a next input signal; and a coefficient update control unit which controls an update rate of a filter coefficient of the adaptive filter and includes: a level calculation unit which calculates a signal level of the input signal; a signal-rising-edge detection unit which detects a rising-edge point; a reverberation section detection unit which detects a reverberation section; and an update rate control unit which sets the update rate to a first rate in the reverberation section and to a second rate in other sections. The adaptive filter updates the filter coefficient at the update rate set by the update rate control unit.

Abstract: There is provided a hearing aid that reduces a possibility of loss. The hearing aid of the present invention includes a microphone 101 configured to collect sound; a hearing aid processing unit 102 configured to perform hearing aid processing to an input signal from the microphone 101; a speaker 103 configured to output a signal processed by the hearing aid processing unit 102 to the outside; and a drop detection unit 104 configured to detect drop by reference to the input signal from the microphone 101.

Abstract: A howling suppression device includes: a subtractor which generates an error signal; an adaptive filter which applies filtering to the error signal; and a coefficient update control unit which controls an update rate of a filter coefficient and includes: a convergence analysis unit which determines whether or not a condition that the degree of convergence of filter characteristics is higher than a criterion value is satisfied; a change amount analysis unit which determines whether or not a condition that the degree of convergence has turned out to be higher is satisfied; and an update rate control unit which sets the update rate to a first rate when both the conditions are satisfied and to a second rate when at least one of the conditions is not satisfied. The adaptive filter updates the filter coefficient at the update rate.

Abstract: A howling suppression device includes a subtractor which subtracts a pseudo feedback signal from an input signal; an adaptive filter which produces a pseudo feedback signal for a next input signal; and a coefficient update control unit which controls an update rate of a filter coefficient of the adaptive filter and includes: a level calculation unit which calculates a signal level of the input signal; a signal-rising-edge detection unit which detects a rising-edge point; a reverberation section detection unit which detects a reverberation section; and an update rate control unit which sets the update rate to a first rate in the reverberation section and to a second rate in other sections. The adaptive filter updates the filter coefficient at the update rate set by the update rate control unit.

Abstract: A howling suppression device includes: a subtractor which generates an error signal; an adaptive filter which applies filtering to the error signal; and a coefficient update control unit which controls an update rate of a filter coefficient and includes: a convergence analysis unit which determines whether or not a condition that the degree of convergence of filter characteristics is higher than a criterion value is satisfied; a change amount analysis unit which determines whether or not a condition that the degree of convergence has turned out to be higher is satisfied; and an update rate control unit which sets the update rate to a first rate when both the conditions are satisfied and to a second rate when at least one of the conditions is not satisfied. The adaptive filter updates the filter coefficient at the update rate.

Abstract: A howling suppression device that can reduce quality deterioration of processed sound includes: a delay unit delaying the input signal to output the delayed input signal as a reference signal; a signal separation unit including an adaptive filter extracting a periodic signal component from the reference signal by adaptively updating a filter coefficient; a howling detection unit detecting an occurrence of howling using at least a signal of the periodic signal component output from the adaptive filter; and a howling suppression unit. The howling suppression unit includes: a suppression filter obtaining the updated filter coefficient from the adaptive filter with timing when the howling detection unit detects the occurrence of the howling, to extract the periodic signal component from the reference signal based on the filter coefficient; and a subtractor subtracting the periodic signal component from the input signal so as to output a signal obtained by the subtraction.

Abstract: The present invention provides a howling detection device capable of detecting the occurrence of howling with a higher degree of accuracy. A howling detection device (300) is provided with a signal level calculating unit (310) calculating, from the input signal, an input signal level being the signal level of an input signal at each given time, a level fluctuation estimated value calculating unit (320) calculating, from the input signal level, a level fluctuation estimated value being a value gradually increasing or decreasing by a given amount with time, a threshold value calculating unit (330) calculating, from the level fluctuation estimated value, a level threshold value changing in accordance with the level fluctuation estimated value, and a howling determination unit (340); which determines that howling occurs in an input signal under the condition that the input signal level being higher than the level threshold value continues for a given time.

Abstract: It is an object of the present invention to provide a howling suppressing apparatus and an acoustic apparatus which can suppress the howling component effectively without suppressing a periodic component other than the howling component. The howling control apparatus comprises a signal separating unit 23 operable to separate an input signal into two components including a periodic component and a nonperiodic component, a howling detecting unit 24 operable to detect a howling component from the input signal on the basis of signals selected from among the input signal and periodic and nonperiodic component signals from the signal separating unit 23, a howling suppressing unit 25 operable to suppress the howling component of the input signal on the basis of detection information from the howling detecting unit 24, and a signal synthesizing unit 26 operable to synthesize a signal from signals from the howling suppressing unit 25.

Abstract: There is provided a hearing aid that reduces a possibility of loss. The hearing aid of the present invention includes a microphone 101 configured to collect sound; a hearing aid processing unit 102 configured to perform hearing aid processing to an input signal from the microphone 101; a speaker 103 configured to output a signal processed by the hearing aid processing unit 102 to the outside; and a drop detection unit 104 configured to detect drop by reference to the input signal from the microphone 101.

Abstract: To provide a howling suppression device which can reduce quality deterioration of processed sound involved in howling suppression in an acoustic feedback loop environment.

Abstract: A howling detector is provided which can discriminate between howling and a signal having a strong narrow-band component, thereby detecting howling with higher accuracy. The howling analyzer includes a frequency analyzing section for analyzing a frequency of a time signal, a level calculating section for calculating a level of a signal output from the frequency analyzing section, a howling detecting section for deciding whether howling occurs or not by analyzing the level having been calculated by the level calculating section, a periodic signal detecting section for deciding whether or not time progression of the level having been calculated by the level calculating section has periodicity, and a howling deciding section for finally deciding whether howling occurs or not based on decision results of the howling detecting section and the periodic signal detecting section.

Abstract: It is an object of the present invention to provide an echo suppressor which is simple in construction in comparison with the conventional echo suppressor, and which can suppress echoes corresponding to the spatial transfer paths, and reduce the amount of calculations necessary to suppress echoes. The echo suppressor is operative under the condition that transfer functions corresponding to spatial transfer paths between two or more loudspeakers (105, 106) and one or more microphones (107, 108) are estimated on the basis of symmetrical arrangement of the loudspeakers (105, 106) and the microphones (107, 108).

Abstract: It is an object of the present invention to provide a howling suppressing apparatus and an acoustic apparatus which can suppress the howling component effectively without suppressing a periodic component other than the howling component. The howling control apparatus comprises a signal separating unit 23 operable to separate an input signal into two components including a periodic component and a nonperiodic component, a howling detecting unit 24 operable to detect a howling component from the input signal on the basis of signals selected from among the input signal and periodic and nonperiodic component signals from the signal separating unit 23, a howling suppressing unit 25 operable to suppress the howling component of the input signal on the basis of detection information from the howling detecting unit 24, and a signal synthesizing unit 26 operable to synthesize a signal from signals from the howling suppressing unit 25.

Abstract: A howling detector is provided which can discriminate between howling and a signal having a strong narrow-band component, thereby detecting howling with higher accuracy. The howling analyzer includes a frequency analyzing section for analyzing a frequency of a time signal, a level calculating section for calculating a level of a signal output from the frequency analyzing section, a howling detecting section for deciding whether howling occurs or not by analyzing the level having been calculated by the level calculating section, a periodic signal detecting section for deciding whether or not time progression of the level having been calculated by the level calculating section has periodicity, and a howling deciding section for finally deciding whether howling occurs or not based on decision results of the howling detecting section and the periodic signal detecting section.

Abstract: Herein disclosed a howling detecting and suppressing apparatus for detecting and suppressing howling sound components comprising: a frequency dividing processing section for converting a plurality of sound time signal segments each corresponding to a time segment into a plurality of sound frequency signal segments each corresponding to a frequency segment; a howling suppressing section for respectively adjusting gains for said sound frequency signal segments converted by said frequency dividing processing section to generate howling-suppressed sound frequency signal segments; a howling detecting section for judging whether a howling sound component is present or not for each of said howling-suppressed sound frequency signal segments generated by said howling suppressing section to detect howling sound frequency signal segments each in which it is judged that said howling sound component is present and non-howling sound frequency signal segments each in which it is judged that said howling sound component is n

Abstract: There are provided a voice switching system and a voice switching method which are capable of carrying out highly accurate voice detection and performing a switching action properly even in the presence of an unstationary noise or under circumstances where the S/N ratio is low.

Abstract: Herein disclosed is a microphone-speaker apparatus, comprising: audio signal dividing means for dividing the audio signal into a plurality of raw component signals each indicative of the raw wave components; coherent component signal extracting means for extracting a plurality of coherent component signals respectively indicative of the coherent wave components from the raw component signals divided by the audio signal dividing means; power value calculating means for calculating the raw power value of each of the coherent component signals extracted by the coherent component signal extracting means; power value adjusting means for adjusting the raw power value of each of the coherent component signals calculated by the power value calculating means to produce an adjusted power value of each of the coherent component signals; power value judging means for judging whether or not the adjusted power value of each of the coherent component signals of the current frame exceeds the adjusted power value of each of t

Abstract: Herein disclosed is a microphone-speaker apparatus, comprising: audio signal dividing means for dividing the audio signal into a plurality of raw component signals each indicative of the raw wave components; coherent component signal extracting means for extracting a plurality of coherent component signals respectively indicative of the coherent wave components from the raw component signals divided by the audio signal dividing means; power value calculating means for calculating the raw power value of each of the coherent component signals extracted by the coherent component signal extracting means; power value adjusting means for adjusting the raw power value of each of the coherent component signals calculated by the power value calculating means to produce an adjusted power value of each of the coherent component signals; power value judging means for judging whether or not the adjusted power value of each of the coherent component signals of the current frame exceeds the adjusted power value of each of t

Abstract: Herein disclosed a howling detecting and suppressing apparatus for detecting and suppressing howling sound components comprising: a frequency dividing processing section for converting a plurality of sound time signal segments each corresponding to a time segment into a plurality of sound frequency signal segments each corresponding to a frequency segment; a howling suppressing section for respectively adjusting gains for said sound frequency signal segments converted by said frequency dividing processing section to generate howling-suppressed sound frequency signal segments; a howling detecting section for judging whether a howling sound component is present or not for each of said howling-suppressed sound frequency signal segments generated by said howling suppressing section to detect howling sound frequency signal segments each in which it is judged that said howling sound component is present and non-howling sound frequency signal segments each in which it is judged that said howling sound component is n