94 results about "Pitch Frequency" patented technology

Successive pitch periods / frequencies are accurately determined in an audio equivalent signal. Using a suitable conventional pitch detection technique, an initial value of the pitch frequency / period is determined for so-called pitch detection segments of the audio equivalent signal. Based on the determined initial value, a refined value of the pitch frequency / period is determined. To this end, the signal is divided into a sequence of pitch refinement segments. Each pitch refinement segment is associated with at least one of the pitch detection segments. The pitch refinement segments are filtered to extract a frequency component with a frequency substantially corresponding to an initially determined pitch frequency of an associated pitch detection segment. The successive pitch periods / frequencies are determined in the filtered signal.

An apparatus and method for deciding an adaptive noise level for bandwidth extension are provided. The apparatus includes a noise level decider for deciding a high-band noise level for bandwidth extension according to tonality of an input signal, a pitch frequency analyzer for detecting a pitch frequency of the input signal and analyzing correlation between the detected pitch frequency and a frequency channel, and a noise level controller for adaptively controlling the decided high-band noise level based on the analyzed correlation of the pitch frequency and the frequency channel.

The invention relates to a speaker recognition method for filtering the emotional tone by using pitch envelop. In the test for speaker recognition, the mutually corresponding cepstrum features and pitch frequency which are firstly extracted from a segment of tone; the gender information is obtained by testing on the gender model which is trained in advance according to the cepstrum features; the thresholds adopted in the method for filtering the emotional tone are determined by gender information; the pitch envelope is picked out according to the thresholds, and then the cepstrum features are filtered according to the serial number of each frame in pitch envelope, thus acquiring the processed cepstrum features; finally, the GMM system test is carried out on the processed cepstrum features.The beneficial effects of the invention are as follows: the inconvenience to the system which needs providing the emotional tone of the speaker in the training or the emotion information of the speech in the test in a traditional method is eliminated, and the recognition performance is increased by 8% compared with traditional ASR system.

The invention relates to a method for separating monaural overlapping speeches based on fractional Fourier transform (FrFT), which belongs to the technical field of audio signal processing. The method comprises the following steps: firstly, preprocessing overlapping speech signals so as to remove mute-section signals of the overlapping speech signals and find out sonant frames; then, carrying out pitch detection on sonant-frame signals based on FrFT so as to separate the fundamental frequencies of the overlapping speeches; and finally, integrating the fundamental frequencies with a sinusoidal model of speech signals so as to synthesize speeches, thereby obtaining each speech signal subjected to separation. The method provided by the invention has the advantages that the fundamental frequencies of a plurality of overlapping speeches can be separated and extracted effectively, and finally, the effective separation of the overlapping speeches can be realized; and the pitch frequencies are extracted based on FrFT instead of traditional fast Fourier transform (FFT), thereby reducing the extension of a harmonic frequency spectrum and then obtaining more accurate fundamental frequencies of original signals. The method provided by the invention is especially suitable for the separation of monaural overlapping speeches containing speeches of two persons.

A system and method of generating electrode stimulation signals for an implanted multi-channel electrode array of a cochlear implant includes processing an acoustic audio signal with a bank of filters. Each filter in the bank of filters is associated with at least one channel having an electrode. The bank of filters includes a first band pass filter that produces a broadband signal b(t) with frequencies that substantially cover at least one of a pitch frequency range of 100 Hz to 400 Hz and a first format range of 400 Hz-1000 Hz. At least one electrode associated with the first band pass filter is activated with electrode stimulation signals based, at least in part, on the broadband signal b(t). The filter bank may include at least one electrode associated with one or more filters other than the first band pass filter, the one or more filters producing signals having only higher frequencies than broadband signal b(t).

There is provided a low-frequency-band voice reconstructing device. A voice signal from which a signal in a low-frequency band is removed is inputted to the device and the device reconstructs the signal in the low frequency band based on the input voice signal. The device comprises a first portion for extracting part of harmonic components of a pitch signal of voice from the input voice signal, a second portion for squaring a signal extracted by the first portion, a third portion for extracting a signal of a pitch frequency and harmonic signals of a lower limit frequency or below of the input voice signal, from the signal obtained by the second portion, and a fourth portion for correcting an amplitude level of the signal extracted by the third portion.

In an automotive system (300), a knock detection scheme is provided for detecting knock events in an internal combustion engine that are sensed by a transducer structure, such as a non-intrusive acoustic accelerometer sensor (310) to generate sensor signal information which is processed by a signal processing structure (312, 316, 318, 326) which extracts digital signal parameters from the sensor signal information to identify a predetermined pitch frequency (330) and any short-term energy increase (328) in the digital signal information which in combination are used to provide a positive indication of engine knock behavior. When a short term Fourier transform (324) is used to extract the digital signal parameters, time frequency resolution may be improved by appropriately windowing the digital signal being transformed.

A pitch frequency estimation device capable of estimating a pitch frequency precisely while reducing the computational complexity required for the estimation of the pitch frequency. In this device, a spectrum extraction unit (104) extracts a pitch-harmonized spectrum from a voice spectrum. A spectral average calculation unit (106) calculates the average of the power of the pitch-harmonized spectra extracted by the spectrum extraction unit (104), in a manner to individually correspond to a plurality of pitch frequency candidates. An estimation unit estimates the pitch frequency by using the average valve calculated by the spectral average calculation unit (106).

An improved method and arrangement for altering musical dynamics of a sound S included in a sound signal is disclosed. The altering of the musical dynamics is performed by filtering and amplification of the sound signal. The filtering is performed by the use of a parametric equalizer, the parametric equalizer having a first gain G1 and a resonance frequency f, being related to a pitch frequency fp of said sound S. The amplification is performed by an amplifier amplifying the sound signal with a second gain G2, the second gain G2 being dependent on the first gain G1.

The invention discloses a distance blur clutter suppression method based on pitch frequency diversity STAP. The method comprises the steps that down-conversion and matched filtering are sequentially carried out on a detected received signal to sequentially acquire the pitch-azimuth-time three-dimensional clutter snapshot model of each range gate, the pitch frequency expression of each range gate and the corresponding clutter compensation item; an appropriate clutter compensation item is used to separate distance blur clutters of different distance rings; due to the fact that pitch frequencies of different distance blur clutters are separated from each other, the distance blur clutter of each distance ring needs a filter with corresponding coefficients for filtering, and then all distance blur clutters are inhibited to solve the problem of distance blur; and finally, after the pitch distance blur clutters are separated, pitch frequency spectrum distribution and digital frequency periodicity are used to acquire the selection criteria of frequency increment. According to the invention, the freedom of a system and the operation complexity are not increased.

The invention discloses a voice conversion method based on convolutive nonnegative matrix factorization. The method comprises the following steps: (1) training a transformation model through training data: carrying out time calibration and parameter decomposition of training voice data, analyzing STRAIGHT spectrum by using a convolutive nonnegative matrix factorization method, and analyzing pitch frequency of source voice and object voice; (2) converting new input voice based on a training model: carrying out parameter decomposition on source voice data A[c] to be converted by employing a STRAIGHT model, realizing sound channel frequency spectrum parameter conversion based on convolutive nonnegative matrix factorization, realizing conversion of the pitch frequency based on obtained mean value and variance in a training phase, and synthesizing voice after conversion, wherein the voice is voice after synthesis and conversion of the STRAIGHT spectrum S[Bc] which is obtained through conversion, the pitch frequency f[Bc] and original aperiodic component ap[Ac]. According to the invention, training effect of voice conversion is improved, and voice quality of conversion voice is improved.

Estimating a speech signal pitch frequency by determining a speech signal frame line spectrum including spectral lines having respective line amplitudes and frequencies, selecting a predefined number of spectral lines having highest amplitudes, fewer then the total number of the spectral lines, calculating a preliminary utility function over a pitch frequency range to provide a preliminary utility function value for each pitch frequency in the range measuring the compatibility of the selected spectral lines with the pitch frequency, identifying a predefined number of preliminary pitch frequency candidates at least partly responsive to the preliminary utility function, where each candidate is a local maximum of the preliminary utility function, calculating a final utility score for each of the candidates, and selecting any of the candidates to be an estimated pitch frequency of the speech signal at least partly responsive to any of the final utility scores.

Apparatus and method for generating high quality synthesized speech having smooth waveform concatenation. The apparatus includes a pitch frequency calculation section, a pitch synchronization position calculation section, a unit waveform storage, a unit waveform selection section, a unit waveform generation section, and a waveform synthesis section. The unit waveform generation section includes a conversion ratio calculation section, a sampling rate conversion section, and a unit waveform re-selection section. The conversion ratio calculation section calculates a sampling rate conversion ratio from the pitch information and the position of pitch synchronization, and the sampling rate conversion section converts the sampling rate of the unit waveform, delivered as input, based on the sampling rate conversion ratio. The unit waveform re-selection section selects, from the sampling-rate-converted unit waveform, the unit waveform having a phase necessary to obtain a synthesized speech waveform which will exhibit smooth waveform concatenation.

Apparatus and methods for its use are provided that relate to an octave / register key for musical wind instruments that combines (i) a vent formed by alignment of an opening of a core and a sidewall aperture of a sleeve, wherein the core is slidably and coaxially mounted within the sleeve, or a vent formed by alignment of sidewall apertures on an inner chamber slidably mounted within an outer chamber, and (ii) the mechanism to open and close such a vent. The device, upon actuation, vents the wind instrument air column to remove the fundamental pitch frequency, and can be mounted anywhere on the body of a musical wind instrument or onto any existing tone hole key of the instrument.

The invention provides a voice extracting method and system and a voice audio playing method and device. The voice extracting method comprises the steps of extracting sound signals where voice and background sound exist jointly from the beginning position of original acoustical signals as a sample, detecting tonic tone from the sample, using the tonic tone as the reference frequency, and comparing the pitch frequency of sound belonging to the same sound source in the sound portion, except the sample, of the original acoustical signals with the reference frequency to determine whether the sound source is voice. The voice extracting method can conveniently extract voice from mixed voice frequency.

The invention discloses a variable pitch control system, a variable pitch control method and a wind generating set. The variable pitch control system comprises a main controller, a variable pitch frequency converter component, variable pitch motors, variable pitch reducers and variable pitch bearings, wherein one variable pitch bearing corresponds to each blade; the plurality of variable pitch reducers are respectively driven by a plurality of variable pitch motor shafts; the plurality of variable pitch reducers are respectively meshed with one variable pitch bearing so as to drive the variable pitch bearing to rotate; and the variable pitch frequency converter component which corresponds to each blade comprises a plurality of frequency converters which comprise a master frequency converter and the rest of slave frequency converters and respectively drive the plurality of variable pitch motors. The variable pitch control on blades of a large or an extra-large wind generating set is realized on the basis of not adding electric and mechanical loads of the variable pitch motors and the variable pitch reducers.

The invention discloses a method and device for extracting a pitch frequency of a sound and a readable storage medium. The method comprises a step of obtaining a sound signal to be detected and transforming the sound signal to be detected from time domain to frequency domain by a short-time Fourier transform, a step of determining a frequency band range of the sound signal to be detected from thefrequency domain and determining a maximum number of harmonics of the sound signal to be detected according to the frequency band range, a step of carrying out energy intensity detection on each frequency point within the frequency band range, and determining a frequency point a with a highest energy intensity according to an intensity detection result, and a step of judging whether a frequency point to be detected with a maximum point exists according to the frequency point a and the maximum number of harmonics, wherein the frequency point to be detected may be a pitch frequency of the soundsignal to be detected or a harmonic component of the pitch frequency if the frequency point to be detected with a maximum point exists, and finally extracting the pitch frequency from the sound signalto be detected. According to the method for extracting a pitch frequency of a sound provided by the invention, the high accuracy can be realized by using low algorithm complexity.

In a speech coding apparatus, a band-pass filter unit separates a residual signal generated by a predictive analyzer into band by band components. Then, a gain calculation unit and a voiced / unvoiced discrimination and pitch extraction unit acquire information on an intensity characterizing each band, information on a result of discrimination as to whether each band-by-band component is a voiced sound or unvoiced sound, and information on a pitch frequency when it is a voiced sound. The acquired information is coded together with a predictive coefficient and is transmitted to a speech decoding apparatus. The speech decoding apparatus generates an excitation signal while reflecting the feature of each band of the original residual signal. This makes the excitation signal an efficient replica of the original residual signal.

The invention provides a control method and a control system of a wind turbine generator. The control method comprises the steps as follows: the wind speed and the rotation speed of a generator are detected; when the wind outlet speed reaches a first wind speed threshold value and the rotation speed of the generator does not reach a first rotation speed threshold value, a variable pitch control instruction for controlling and changing a blade angle is output to a variable pitch frequency converter of the wind turbine generator; and when the rotation speed of the generator is judged to reach the first rotation speed threshold value, a control instruction for executing grid-connected operation is output to a generator frequency converter. According to the control method and the control system of the wind turbine generator, the wind speed and the rotation speed of the generator are detected, the variable pitch is controlled before grid-connected generation of the generator, and an optimal attack angle is tracked furthest, so that the utilization rate of wind energy is improved.

A personal care implement comprises a head and a handle, the head being repeatedly attachable to and detachable from the handle. The personal care implement exhibits a sound when the head gets attached to or detached from the handle, thereby providing a signal of secure attachment or detachment. The sound is characterized by a tonal component of about 4000 Hz to about 6000 Hz, preferably over a time length of about 0.1 s to about 0.3 s, on a tonality frequency vs. time analysis.

A spectrum modifying method and the like wherein the efficiencies of the signal estimation and prediction can be improved and the spectrum can be more efficiently encoded. According to this method, the pitch period is calculated from an original signal, which serves as a reference signal, and then a basic pitch frequency (f0) is calculated. Thereafter, the spectrum of a target signal, which is a target of spectrum modification, is divided into a plurality of partitions. It is specified here that the width of each partition be the basic pitch frequency. Then, the spectra of bands are interleaved such that a plurality of peaks having similar amplitudes are unified into a group. The basic pitch frequency is used as an interleave pitch.

Apparatus and methods for its use are provided that relate to an octave / register key for musical wind instruments that combines (i) a vent formed by alignment of an opening of a core and a sidewall aperture of a sleeve, wherein the core is slidably and coaxially mounted within the sleeve, or a vent formed by alignment of sidewall apertures on an inner chamber slidably mounted within an outer chamber, and (ii) the mechanism to open and close such a vent. The device, upon actuation, vents the wind instrument air column to remove the fundamental pitch frequency, and can be mounted anywhere on the body of a musical wind instrument or onto any existing tone hole key of the instrument.

The read-back signal from a HDD head is demodulated to find the pitch frequency of the head, which can be compared to a baseline value to determine if it has increased, indicating a possible failure due to contamination or lubricants pick up. Or, the pitch frequency can be used during manufacturing of a burnished pad head to determine when burnishing has been completed.

In a speech coding apparatus, a band-pass filter unit separates a residual signal generated by a predictive analyzer into band by band components. Then, a gain calculation unit and a voiced / unvoiced discrimination and pitch extraction unit acquire information on an intensity characterizing each band, information on a result of discrimination as to whether each band-by-band component is a voiced sound or unvoiced sound, and information on a pitch frequency when it is a voiced sound. The acquired information is coded together with a predictive coefficient and is transmitted to a speech decoding apparatus. The speech decoding apparatus generates an excitation signal while reflecting the feature of each band of the original residual signal. This makes the excitation signal an efficient replica of the original residual signal.

The invention discloses a detection platform for a variable pitch frequency converter of a variable pitch system. The detection platform comprises a PC operation part and a testing part which are connected with the variable pitch frequency converter, wherein the testing part comprises a beckhoff module group, an enabling relay, a direct-current power supply, a direct-current voltmeter, an alternating current power supply, an alternating current voltmeter, a discharge resistor, another direct-current voltmeter connected with the discharge resistor in parallel, a motor and an alternating current ammeter, wherein the beckhoff module group and the enabling relay are connected with the frequency converter; the discharge resistor is used for discharging electric energy of a direct-current bus; the motor is connected with the variable pitch frequency converter; the alternating current ammeter is connected with the motor in parallel. The invention further discloses a detection device comprising the detection platform and a detection method for the variable pitch frequency converter of the variable pitch system. By simulating the normal situation and the special situation of the variable pitch system in a wind generator set in the practical operation process, the detection platform, the detection device and the detection method can be used for detecting the property of the variable pitch frequency converter comprehensively; the working state of the frequency converter is displayed through a triggering signal and a feedback signal; the electric characteristics of the frequency converter are detected through data measured by using digital voltmeters / ammeters, and further hidden dangers can be eliminated and the repairing quality of a product is improved.

The invention discloses a power limiting control method for a variable speed constant frequency wind turbine generator and capable of reducing the variable pitch frequency. According to the method, a rotation speed critical decrease variable is introduced into a variable pitch controller, characteristics of a wind turbine are fully utilized, the unbalanced power is adjusted through kinetic energy of a wind wheel preferably, the action mechanism of a variable pitch system is optimized, and the problem that a variable pitch mechanism acts frequently in the high-air-speed stage is effectively solved. According to the method, by changing the decrease action value of the variable pitch system, the unbalanced kinetic energy is released or absorbed through the wind wheel of the wind turbine preferably, the action frequency and action amplitude of the variable pitch system can be effectively reduced on the premise that the target power output of the wind turbine is met, and accordingly the mechanical fatigue of the variable pitch system is relieved, and the service life of the variable pitch system is prolonged.