摘要:
A low complexity howling suppression system and method for portable karaoke system are provided. In the howling suppression, at least one infinite impulse response (IIR) filters are introduced for estimating the acoustic feedback picked up by the microphone from the real environment, and thereby to cancel out the acoustic feedback from the microphone input signal.
摘要:
Amplitude, phase and frequency of a sine wave to be generated are calculated on the basis of feature quantity s1 delivered to feature quantity detecting means (2), and are sent to initialization means (3). The initialization means (3) calculates first two points of the sine wave to send the points thus calculated to oscillator (sine wave generating means) (4) as initial value s4. The oscillator (4) sequentially calculates values of respective sample points of waveform by using recurrence formula in accordance with initial value or values instructed from the initialization means (3) to thereby generate a sine wave signal. Thus, sine wave generation is performed without performing modulo-addressing.
摘要:
A song-matching system, which provides real-time, dynamic recognition of a song being sung and providing an audio accompaniment signal in synchronism therewith, includes a song database having a repertoire of songs, each song of the database being stored as a relative pitch template, an audio processing module operative in response to the song being sung to convert the song being sung into a digital signal, an analyzing module operative in response to the digital signal to determine a definition pattern representing a sequence of pitch intervals of the song being sung that have been captured by the audio processing module, a matching module operative to compare the definition pattern of the song being sung with the relative pitch template of each song stored in the song database to recognize one song in the song database as the song being sung, the matching module being further operative to cause the song database to download the unmatched portion of the relative pitch template of the recognized song as a digital accompaniment signal; and a synthesizer module operative to convert the digital accompaniment signal to the audio accompaniment signal that is transmitted in synchronism with the song being sung.
摘要:
Digital signal processing (e.g. filtering) apparatus comprises pipelined digital signal processing means for generating each output sample of an output digital signal from input samples of an input digital signal by combining the input samples with a plurality of subsets of a set of filter coefficients associated with that output sample during a respective plurality of sample periods of the input digital signal; and coefficient generating means for supplying sets of filter coefficients to the signal processing means in response to the current state of a filter control signal. The coefficient generating means is operable to supply the plurality of subsets of each set of filter coefficients to the signal processing means during the respective plurality of sample periods of the input digital signal.
摘要:
In a filter device, a filter coefficient calculation circuit has a parameter table. The parameter table stores a plurality of sets of filter coefficients associated with a first parameter based on a frequency and a second parameter based on respective plurality of levels representing a degree of attenuation or enhancement of a gain of a filter in filter characteristics. The filter coefficient calculation circuit extracts a set of filter coefficients from a parameter table with the use of the first parameter and the second parameter determined according to a frequency and a strength of a musical sound signal, and outputs the extracted set of filter coefficients to the filter. The filter circuit performs filter processing for the musical sound signal, based on the filter characteristics determined by the set of filter coefficients.
摘要:
Efficient recursive audio processing of one or more input data streams using a multistage processor for performing one or more predetermined functions and programmable audio effects. A first stage performs a first predetermined function, such as frequency shifting function. Intermediate results are preferably mixed. The second stage applies programmable audio effects to the mixed data, such as a reverberation effect, and stores the second stage output in a destination mix bin. The second stage output is preferably transferred to a main memory accessible to a primary processor. The second stage output is directed back to the first stage of the multistage processor to perform a second predetermined function, such as three dimensional spatialization. The primary processor modifies parameters of the first predetermined function to efficiently perform dynamic operations, such as Doppler shifts and volume transitions between multiple sound sources and a mixture of those sounds as a single point source.
摘要:
A percussive sound contains both harmonic and non-harmonic frequency spectral content. To reproduce a particular percussive sound, such as the sound of a drum or cymbal or hand clap, for example, the harmonic and non-harmonic content are determined empirically. Also, and tendency of the harmonic content to change over time, and the temporal aspects of attack, sustain, and decay are likewise determined empirically. These attributes are represented in the invention in a percussive sound file which includes a harmonic content profile (502), noise shape filter (504), Doppler shift profile (506), and a time wave shaping profile (508). The harmonic content profile is used by an FM generator (114) to generate a frequency modulated signal (116). The noise shape profile is used by a noise generator (134) to generate and shape the non-harmonic spectral content. While the sound is being generated, the Doppler shift profile is used to adjust the base frequency of the FM signal. The harmonic and non-harmonic signals are scaled (142, 144) and summed (146). The summed signal is then shaped (150) in time to substantially simulate the attack, sustain, and decay properties of the sound. The shaped, summed signal is then played by an audio circuit and converted to an acoustic signal.
摘要:
Digital signal processing (e.g. filtering) apparatus comprises pipelined digital signal processing means for generating each output sample of an output digital signal from input samples of an input digital signal by combining the input samples with a plurality of subsets of a set of filter coefficients associated with that output sample during a respective plurality of sample periods of the input digital signal; and coefficient generating means for supplying sets of filter coefficients to the signal processing means in response to the current state of a filter control signal. The coefficient generating means is operable to supply the plurality of subsets of each set of filter coefficients to the signal processing means during the respective plurality of sample periods of the input digital signal.
摘要:
Disclosed herein is a digital audio signal processing apparatus of a type wherein a graphic equalizer including a plurality of filters connected in series to one another is subjected to arithmetic operation processing to be defined to thereby output the result of its processing as data therefrom. When a change-over command is generated, one filter out of the plurality of filters except for filters positioned at both ends is supplied to one of two output terminals with output data of a filter immediately before said one filter, the stored data is applied to the input of a filter immediately after said one filter and output data of a final filter is applied to the other of said two output terminals so as to define two graphic equalizers. Thus, where it is desired to carry out a change in the mode from arithmetic operation processing which defines a graphic equalizer comprising a plurality of bands to arithmetic operation processing which defines two-separated graphic equalizers comprising a plurality of bands or to the contrary, where it is desired to carry out a change in the mode contrary to the mode referred to above, the change in the arithmetic operation processing can be completed in a relatively short time.
摘要:
In a filter device, a filter coefficient calculation circuit has a parameter table. The parameter table stores a plurality of sets of filter coefficients associated with a first parameter based on a frequency and a second parameter based on respective plurality of levels representing a degree of attenuation or enhancement of a gain of a filter in filter characteristics. The filter coefficient calculation circuit extracts a set of filter coefficients from a parameter table with the use of the first parameter and the second parameter determined according to a frequency and a strength of a musical sound signal, and outputs the extracted set of filter coefficients to the filter. The filter circuit performs filter processing for the musical sound signal, based on the filter characteristics determined by the set of filter coefficients.