Leland Stanford Junior University

Ceribell, Inc.

Christopher D Chafe

Josef Parvizi

Xingjuan Chao

Ronald C Eddington, Jr

A handheld device for sonifying electrical signals obtained from a subject is provided. The device can utilize at least one of several operations including (but not limited) digitizing signals from electrodes, adjusting the signals based on accelerometer input, filtering the signals, conditioning the signals according to conditioning parameters, modulating the signal according to sound synthesis parameters, and generating sound from the representations of the signals to accomplish sonification. The device can include an analog-to-digital (A/D) converter to digitize the one or more electrical signals and a processor that receives the one or more digitized electrical signals and produces a representation of an acoustic signal. The device further includes a speaker system that sonifies the representation of the acoustic signal.

Handheld or wearable device for recording or sonifying brain signals

A digital processor system having one or more processors and memory obtains a time-domain signal representing brain activity, the time-domain signal having a time varying signal value. The system concurrently generates a set of acoustic parameters, including a plurality of time-varying acoustic parameters, where one or more of the plurality of time-varying acoustic parameters is modulated in accordance with at least the signal value of the time-domain signal. The system combines the concurrently generated set of acoustic parameters to produce a representation of an acoustic signal corresponding to the time-domain signal, where the acoustic signal, in audible form, manifests one or more audibly discernible variations across a plurality of stages of a brain activity event.

Method of sonifying brain electrical activity

A digital processor system obtains at least one time-domain signal representing brain activity and at least one time-domain signal representing heart activity, each having a time-varying signal value. The system produces representations of a plurality of acoustic signals, each of which corresponds to a respective time-domain signal and is produced by concurrently generating a plurality of acoustic parameters, including a plurality of time-varying acoustic parameters. One or more of the plurality of time-varying acoustic parameters is modulated in accordance with at least the signal value of the respective time-domain signal. Each representation of an acoustic signal of the plurality of acoustic signals is further produced by combining the concurrently generated plurality of acoustic parameters to produce the representation of the acoustic signal corresponding to the respective time-domain signal. The system combines the representations of each of the plurality of acoustic signals to produce a combined acoustic signal.

Method of sonifying signals obtained from a living subject

A method of determining locations of microseismic events caused by a hydrofracking process is disclosed. The method includes: measuring audio signals using an array of geophones deployed in a monitoring well during hydraulic fracturing; modifying the audio signals according to a predefined nonlinear distortion operator to generate a modified audio signal, wherein the modified audio signal has audible components in a predefined frequency range beyond a cutoff frequency defined by a sampling rate of the respective measured audio signals; and playing the modified audio signals through a stereo or multi-channel speaker system, wherein a user of the stereo or multi-channel speaker system is able to determine the locations of the microseismic events from listening to the modified audio signals.

Determining location information of microseismic events during hydraulic fracturing

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.

Glitch-free frequency modulation synthesis of sounds

A distributed acoustic reverberator including a network audio connection between at least two separated locations is provided. When a sound is emitted at one of the locations, the reverberator provides a reverberation signal to that location with a procedure. An algorithm implemented by the distributed reverberator includes such a procedure for each location. The delay of the network connection is an input to the procedures. Thus, a shared and acoustically consistent space including the separated locations is provided. The reverberator may include procedures for providing a reverberation signal to one location responsive to sound at another location.

Distributed acoustic reverberation for audio collaboration

A technique for measuring, evaluating, and presenting virtual network connection latency and virtual network connection stability information allows users to easily evaluate the quality of internet connections in real time. The technique uses audible sounds to represent the round trip time (RTT) of an end-to-end network path as well as other connection qualities. This can be either by sounding tones that depend on momentary measurements obtained by &ldquo;pinging&rdquo; a remote host, or by driving the internet connection as the delay loop of a musical tone synthesis process. The synthesized tone is presented to a user in an audio, tactile, and/or visual manner. In a preferred embodiment, the synthesized tone is played to the user. Because the internet connection delay is used in the tone synthesis process, the pitch of the synthesized tone is a direct indicator of the real-time network connection latency. Changes in pitch indicate changes in connection latency.

Method for evaluating quality of service of a digital network connection

A music synthesizer simulates the musical tones of wind instruments. The synthesizer includes a vopex noise generator, an edge tone nonlinearity function driven by the differential between a blowing pressure signal and a feedback signal from the resonator. The vopex noise generator feeds its noise output signal back into itself so as to generate a noise 'votex'. The vopex noise generator furthermore modulates the spectral content of the generated noise fluctuates in a manner that is period synchronous with the resonator output signal. As a result, the noise vopex signals mimic the turbulence associated with air blown into wind instruments by switching between structured and chaotic modes of operation in a manner that is period synchronous with the resonator output signal. The transfer characteristic of the edge tone nonlinearity function is dynamically controlled by the noise signal so as to change the operating point of the edge tone nonlinearity. Since the noise signal is changing in a manner that is period synchronous with the resonator output signal, the transfer characteristic of the edge tone nonlinearity function is also dynamically modulated in a manner that is period synchronous with the resonator output signal. The resulting period synchronously modulated edge tone signal is injected into the resonator, creating microvariations in the amplitude and frequency of the output signal generated by the resonator, thereby mimicking the noise component of the sounds produced by acoustic wind instruments.

Music synthesizer and method for simulating period synchronous noise

A music synthesizer simulates the musical tones of bowed string and wind instruments. The synthesizer includes a noise generator which generates pulsed noise signals, as well as a resonant system or signal generator which generates deterministic or periodic signals. In one embodiment, the pulsed noise signals are combined with the periodic signals to generate an improved synthesized musical sound. In another embodiment, pulsed noise is added to an excitation signal for energizing a resonating system, which may or may not be dynamically coupled to the excitation generator, resulting in the generation of synthesized sound having appropriate noise characteristics for bowed string and wind instruments.

Growing community of inventors

Palo Alto, CA, United States of America

Christopher D Chafe