摘要:
An interrupt sensitive extract byte instruction scheme is presented herein. The interrupt sensitive extract by instruction extracts bytes from data, depending on the presence of an interrupt. The extract byte instruction extracts bytes from data in the absence of the interrupt and does not extract bytes in the presence of the interrupt. The interrupt can be triggered by a set of counters that count the number of extracted bytes. By loading the counters with a particular number, the interrupt can be generated when the particular number of data bytes is extracted.
摘要:
An apparatus carries out an adaptive pulse code modulation process on voice data and records them in a solid memory which is detachably attached to the apparatus. The code bit number is switched, depending on the selected recording mode. A filter for suppressing a high-voice region of the frequency band of the voice data is used, and there is provided a selector for applying this filter at the time of voice reproduction selectively either always or according to the code bit number.
摘要:
A vocoder according to the present invention includes an analyzer portion and a synthesizer portion. The analyzer portion encodes an input frame of speech on the basis of a candidate excitation selected from a group of candidate excitations stored in memory. Instead of transmitting the actual candidate excitation to the synthesizer portion, the analyzer portion generates and provides to the synthesizer portion a variable length index code that identifies the selected candidate excitation. The synthesizer portion stores in memory the same plurality of candidate excitations as the analyzer portion. The synthesizer portion uses the variable length index code to obtain from its memory the candidate excitation originally selected by the analyzer portion. The synthesizer portion reconstructs the input frame of speech on the basis of the obtained candidate excitation.
摘要:
A speech signal input from a microphone is distributed by a distribution amplifier. Using output signals of a filter group of cos phase having cut-off frequency moderate on low frequency side and steep on high frequency side and of similar filter group of sin phase, stability index is calculated based on magnitude of amplitude modulation and magnitude of frequency modulation of the signals, by stability index calculating portion and fundamental frequency extracting portion. Based on the result of calculation, approximate value of fundamental frequency is calculated based on an output of a channel indicating maximum stability, and based on the approximate value of fundamental frequency, instantaneous frequency extracting portion extracts precise instantaneous frequency as fundamental frequency, interpolating value of instantaneous frequency from adjacent frequency channels.
摘要:
Apparatus for processing acoustic features extracted from a sample of speech data forming a feature vector signal every frame period includes a first linear prediction analyzer, a vector quantizer, at least one partitioned vector quantizer and a scalar quantizer. The first linear prediction analyzer performs a linear prediction analysis on the feature vector signal to generate a first error vector signal. Next, the vector quantizer performs a vector quantization on the first error signal thereby generating a first index corresponding to a first prestored vector signal which is an approximation of the first error vector signal. The vector quantizer also generates a residual vector signal which is the difference between the first error vector signal and the first prestored approximation vector signal. Next, the at least one partitioned vector quantizer performs a partitioned vector quantization on a first portion of the residual vector signal thereby generating at least one second index corresponding to a second prestored vector signal which is an approximation of the first portion of the residual vector signal. Next, the scalar quantizer performs a scalar quantization on a second portion of the residual vector signal thereby generating a third index corresponding to a prestored scalar signal which is an approximation of the second portion of the residual vector signal. The first, second and third indices are combined to form an encoded vector signal which is a compressed representation of the feature vector signal. The encoded vector signal may be transmitted and/or stored as desired. The feature vector signal may be reconstructed from the encoded vector signal by adding the corresponding prestored signals to the encoded vector signal to form a decompressed representation of the feature vector signal.
摘要:
A reproduction speed of speech sound changing apparatus which reproduces speech data at a speed in which essential part thereof can be caught so that the outline of the speech sound can be grasped even when changing the reproduction speed, besides remarkably reduces the whole reproducing time wherein a reproducing speed in each predetermined period is calculated according to a parameter value in every predetermined period of speech data in accordance with such a manner that a part having a high parameter value such as high power, high pitch or the like of speech data is judged to be the part, where important contents are involved, and such part of important contents is reproduced at such a speed that the contents can be caught, while the parts other than that described above are reproduced either at such a speed that the whole reproduction of speech data can be completed within a required time, or reproduced by skipping over the parts if at thus determined reproduction speed, reproduced speech sound cannot be caught, as a result of paying attention to such fact that voice is louder or pitch of voice becomes higher in the part containing important contents in speech data.
摘要:
A method and apparatus for distributing audio signals from one of a plurality of audio sources to an output connect compressed audio signals from each one of the plurality of audio sources to an audio processor. Uncompressed audio signals are derived from the compressed audio signals. The compressed audio signal from one of the plurality of audio sources is selectively coupled to the output based upon the uncompressed audio signals. In a preferred embodiment, the compressed audio signal from one of the plurality of audio sources is coupled to the output selectively in accordance with speech information detected in the uncompressed audio signals from the plurality of audio sources. The method and apparatus include mixing, selectively, the uncompressed audio signals from the plurality of audio sources into a composite uncompressed audio signal; compressing the uncompressed composite signal into a corresponding compressed composite signal; and connecting the compressed composite signal or the selected one of the compressed audio signals to the output selectively in accordance with the uncompressed audio signals. In a preferred embodiment of the invention, the compressed composite signal is fed to the output when speech audio signals are detected from more than one source and the selected one of the compressed audio signals is coupled to the output when speech is detected from only one of the sources.
摘要:
To overcome the problem of poor representation of the background noise, the present invention includes a noise parameter generator (40) which uses a weighted average of auto-correlation values of the input signal generated during the noise-analysis phase. The weighting function gives less weight to the auto-correlations during the first few frames (as they may contain speech) and more weight to frames towards the end of this phase. Also included, to overcome the bursty nature of comfort noise, is a comfort noise generator (50) which gradually changes the nature of the signal from speech to pseudo-random noise after the speech-burst The comfort noise generator (50) of the present invention excites the auto-regressive filter corresponding to the noise model with a weighted combination of the past excitation and pseudo-random noise.
摘要:
Apparatus for expanding the bandwidth of speech signals such that a narrowband speech signal is input and digitized, the spectral envelope information and residual information are extracted from the digitized signal by linear predictive coding analysis, the spectral envelope information is expanded into wideband information by a spectral envelope converter, the residual information is expanded into wideband information by a residual converter, the converted spectral envelope information and residual information are combined to produce a wideband speech signal, frequency information not contained in the input signal is extracted from the obtained wideband speech signal by a filter, and the resulting signal is added to the original digitized input signal, and the obtained signal is converted into an analog signal as the output signal of the apparatus. The apparatus comprises a linear mapping function codebook used for converting spectral parameters, and a weights calculator and an adder for weighing and summing function outputs.
摘要:
A first vector quantizer generates output codevectors corresponding in number to a number determined by a predetermined number of bits through linear coupling of integer coefficients of a predetermined number of base vectors stored in a base vector memory. A second vector quantizer determines coefficients of the base vectors according to at least one of output indexes of the output codevectors.