The invention includes a method, apparatus, and computer program to selectively suppress wind noise while preserving narrow-band signals in acoustic data. Sound from one or several microphones is digitized into binary data. A time-frequency transform is applied to the data to produce a series of spectra. The spectra are analyzed to detect the presence of wind noise and narrow band signals. Wind noise is selectively suppressed while preserving the narrow band signals. The narrow band signal is interpolated through the times and frequencies when it is masked by the wind noise. A time series is then synthesized from the signal spectral estimate that can be listened to. This invention overcomes prior art limitations that require more than one microphone and an independent measurement of wind speed. Its application results in good-quality speech from data severely degraded by wind noise.

Method and apparatus for suppressing wind noise

A voice enhancement logic improves the perceptual quality of a processed signal. The voice enhancement system includes a noise detector and a noise attenuator. The noise detector detects and models the noise associated with rain. The noise attenuator dampens or reduces the rain noise from a signal to improve the intelligibility of an unvoiced, a fully voiced, or a mixed voice segment.

System for suppressing rain noise

A system improves the perceptual quality of a speech signal by dampening undesired repetitive transient noises. The system includes a repetitive transient noise detector adapted to detect repetitive transient noise in a received signal. The received signal may include a harmonic and a noise spectrum. The system further includes a repetitive transient noise attenuator that substantially removes or dampens repetitive transient noises from the received signal. The method of dampening the repetitive transient noises includes modeling characteristics of repetitive transient noises; detecting characteristics in the received signal that correspond to the modeled characteristics of the repetitive transient noises; and substantially removing components of the repetitive transient noises from the received signal that correspond to some or all of the modeled characteristics of the repetitive transient noises.

Repetitive transient noise removal

A speech enhancement system improves the perceptual quality of a processed voice signal. The system improves the perceptual quality of a voice signal by removing unwanted noise components from a voice signal. The system removes undesirable signals that may result in the loss of information. The system receives and analyzes signals to determine whether an undesired random or persistent signal corresponds to one or more modeled noises. When one or more noise components are detected, the noise components are substantially removed or dampened from the signal to provide a less noisy voice signal.

Signature noise removal

A system for, and method of, increasing sample rate converter filter coefficient derivation and running speed and a digital signal processor incorporating the system or the method. In one embodiment, the system includes: (1) a coefficient table containing a matrix of predefined filter coefficients for each of a plurality of alpha intervals and (2) an intra-range interpolator that adjusts the predefined filter coefficients for a specific alpha within the alpha interval to yield filter coefficients specific to the alpha.

System and method for increasing sample rate converter filter coefficient derivation speed

Using stored discrete samples of filter coefficients at each of a plurality of discrete operating points, a filter control (e.g., CPU) provides dynamic control of a digital filter through an interpolator in accordance with a variable input indicative of a desired operating point (e.g., cutoff frequency) of the digital filter. In response to a large change in the desired operating point, the control produces a succession of operating point subgoals progressively approaching the changed desired operating point and a corresponding succession of filter coefficient subgoals. Each filter coefficient subgoal is calculated as a function of stored discrete filter coefficient samples near each operating point subgoal. In response to a new parameter set from the filter control, containing a new subgoal of the coefficients, the interpolator starts coefficient interpolating to smoothly move the operating point of the digital filter toward the new subgoal. By starting the interpolating operations after the updating of the parameter set has been completed, synchronization may be established among the interpolating operations on the coefficients.

Digital filter system with changeable cutoff frequency

Filter coefficients corresponding to a plurality of discrete cutoff frequencies are stored in advance in a memory and a filter coefficient corresponding to a specified cutoff frequency is generated by performing an interpolation referring to the filter coefficients stored in the memory, thereby saving the capacity of the memory. When a resonance index is to be specified in addition to the cutoff frequency, filter coefficients corresponding to two difference resonance indexes are acquired by the interpolation, then a new filter coefficient is acquired by executing the interpolation referring to these two filter coefficients.

Digital filter with dynamically variable filter characteristics

A sensor obtains an angular rate of a stick member. A sound source map includes plural areas disposed in a virtual space. CPU presumes a direction of a turning axis of the stick member based on the angular rate obtained by the sensor, while a user is operating the stick member, calculates an angular rate of a top of the stick member based on the angular rate obtained by the sensor with the angular rate in the longitudinal direction of the stick member removed, calculates a position of the holding member in the virtual space after a predetermined time, based on the recent direction of the turning axis of the stick member and recent angular rate of the top of the stick member, and sends a sound generating unit a note-on event of a musical tone assigned to an area corresponding to the calculated position among the plural areas.

Playing apparatus, method, and program recording medium

An electronic musical instrument includes: a contact sensor that generates lip detection information from an operation by a performer; and a controller that derives a lip contact area from the lip detection information generated by the contact sensor, and performs musical note control of an electronic sound source in accordance with the derived lip contact area.

Electronic wind instrument

In the preset invention, in an initial stationary state of a drumstick section, a CPU stores acceleration that occurs due to gravity and is obtained by an acceleration sensor in a RAM, obtains, at every predetermined timing, acceleration that occurs due to a motion provided to the drumstick section and is obtained by the acceleration sensor at a predetermined timing, accumulates the accelerations each obtained at the predetermined timing for each predetermined interval, and conforms the accelerations obtained by accumulation to the acceleration stored in the RAM

Ryutaro Hayashi

Papers

Digital filter system with changeable cutoff frequency

Digital filter with dynamically variable filter characteristics

Playing apparatus, method, and program recording medium

Electronic wind instrument

Orientation detection device, orientation detection method and program storage medium