摘要:
A time-varying formant is generated at a formant frequency by generating first and second harmonic phase signals having first and second harmonic numbers, respectively, in relation to a modulation frequency. The first and second harmonic phase signals are generated in proportion to a master phase signal, which varies at the modulation frequency, modulo a factor corresponding to their harmonic numbers. First and second sound signals, based on the first and second harmonic phase signals, are frequency modulated to create an arbitrarily rich harmonic spectrum, depending on an FM index. The time-varying formant is generated by generating a time-varying combination of the first and second harmonic sound signals, weighting the first and second harmonic sound signals in accordance with their spectral proximities to the formant frequency. One or more of the harmonic numbers are updated when the time-varying formant frequency passes the frequency of either sound signal.
摘要:
A method and system of audio synthesis capable of reducing CPU load is disclosed, which establishes a parameter look-up table in a read-only memory (ROM). When a computer system synthesizes audio signals, the required coefficients are obtained from the table, which relatively reduces the amount of parameter transferred between an audio chip and a central processing unit (CPU). Thus, the load of the CPU can be reduced.
摘要:
A frequency modulation (FM) tone signal generator for generating a FM tone signal is disclosed. The tone signal generator includes a waveform generator having a plurality of wave tables, a selector and an enveloper. The waveform generator furnishes a waveform signal in response to a phase angle address signal. Each wave table stores a different waveform. The selector selects one of the wave tables in response to a plurality of selection signals such that the selected wave table largely provides the waveform signal upon being addressed largely by the phase angle address signal. Selection of the selected wave table varies with each selection signal. The enveloper impresses an envelope signal on the waveform signal. The envelope signal is used as a carrier or modulator for generating the FM tone signal.
摘要:
A musical instrument employing probabilistic wavetable-modification method of producing musical sound. A randomly initialized wavetable which is periodically accessed to provide an output signal which determines the musical sound. The output signal from the wavetable is probabilistically modified and stored back into the wavetable as modified data. The modified data, after a delay, is accessed from the wavetable and thereby becomes a new output signal. This process is periodically repeated whereby each new output signal is stored (after possibly being modified) back into the wavetable to produce rich and natural musical sound.
摘要:
A content data generating device includes a first storage configured to store content data including at least either video information or audio information, a second storage configured to store variation data representing change of a parameter on the content data, a designator configured to designate a portion of the variation data, and a content data generator configured to process the content data according to a value of the parameter of the portion of the variation data designated by the designator to generate processed content data.
摘要:
A system and method are disclosed for emulating a frequency modulation sound chip with minimal hardware and utilizing the excess capacity of current computer systems. In one embodiment, the frequency modulation emulation apparatus includes a frequency modulation emulator suitable to communicate with a computer system. The frequency modulation emulator provides an addressable memory space, substantially similar to an emulated addressable memory space of the emulated frequency modulation sound chip, such that a frequency modulation application implemented on the computer system can communicate with the frequency modulation emulator. The emulator chip receives audio data through the addressable memory space from the frequency modulation application and, the frequency modulation application is unaware that the frequency modulation emulator is receiving the audio data rather than the emulated frequency modulation sound chip. A frequency modulation generator is implemented on the computer system. The frequency modulation generator receives the audio data from the frequency modulation generator. The frequency modulation generator processes the audio data to produce an audio signal in a manner that is substantially similar to the operation of the emulated frequency modulation sound chip. Thus, minimal hardware is used to emulate a frequency modulation sound chip, and utilizing the excess capacity of current computer systems.
摘要:
A plurality of digital signal processors are provided in parallel relation to each other, and a series of operations for desired sound signal synthesis or processing is divided into a plurality of operation groups to be allocated to the signal processors. First and second buses are connected to each of the signal processors so that parameters necessary for the operations are distributively supplied to the signal processors via the first bus and the operation result of each of the signal processors is transferred to another digital signal processor or an output port via the second bus. One digital signal processor receives the output data from another digital signal processor via the second bus so as to perform a predetermined operation using the received data. The desired sound signal processing is thus executed by combinations of the operations performed by such signal processors. Where sound signal processing is executed in a plurality of channels on a time-divisional basis, the time-divisional channel timing of each digital signal processor is set independently of that of other digital signal processors. By setting synchronized tone generation designating data for each channel, synchronized tone generation is controllably performed in selected channels.
摘要:
A method and apparatus for applying a musical feedback signal to the human brain, or any other brain, to induce controllable psychological and physiological responses. A signal representing the ongoing electroencephalographic (EEG) signal of a brain preferably is obtained from the electrode location on the scalp known as CZ or P3 in clinical notation. A signal processor converts the ongoing EEG into electrical signals which are converted into music by synthesizers. The music is acoustically fed back to the brain after a time delay calculated to shift the phase of the feedback in order to reinforce specific or desired ongoing EEG activity from the scalp position of interest. The music is comprised of at least one voice that follows the moment-by-moment contour of the EEG in real time to reinforce the desired EEG activity. The music drives the brain into resonance with the music to provide a closed loop or physiological feedback effect. Preferably, the musical feedback comprises additional voices that embody psychoacoustic principles as well as provide the content and direction normally supplied by the therapist in conventional biofeedback. The invention contemplates numerous applications for the results obtained.
摘要:
A musical instrument for producing musical sound including a wavetable for storing a plurality of samples in wavetable locations. An address generator addresses wavetable locations for selecting stored samples to provide audio output signals and for selecting stored samples to be modified and restored. New addresses for specifying wavetable locations are provided employing a modification operation independent from an output operation.
摘要:
A new, performer played, real time, multitonal, multimbral musical instrument consists of speed and force sensitive keys in which time domain multiplexing is used to find and associate one and only one tone generator, not otherwise busy, with any key that is depressed. The sound generator disclosed can provide very realistic simulations of the flute, oboe, trumpet, French horn, trombone through the provision of various types of modulations in amplitude and frequency of the various partials, as is characteristic of each instrument simulated, and filtered noise. Glissandi are provided from one note to another and are controlled from the pair of keys involved by the relative pressure with which they are depressed. For the nonpercussive tonalities, the speed with which a key is depressed, which is determined by differentiating the force, may be used to cause the attack transient to behave in a manner very characteristic of the instrument being simulated. The force with which a key is depressed is determined from the rate of rise of the potential across a capacitive keying system excited through a resistor. Percussive sound generators are provided also; the intensity of the note generated by these generators is determined by the speed with which the associated key is depressed. The force with which the associated key is depressed can be used to determine the rate of automatic repetition of the note. The speed with which a key is depressed can also be used for nonpercussive instruments to alter the character of the attack transient.