Virtual Positioning Patents (Class 381/310)
  • Publication number: 20020051548
    Abstract: An acoustic signal reproduction device includes a reproduction speaker and a signal processing section for generating an acoustic signal for causing a listener to recognize a reference speaker. The signal processing section includes a compensation data input section for receiving compensation data from the outside of the acoustic signal reproduction device and a calculation section for calculating the acoustic signal based on the audio signal and the compensation data and outputting the acoustic signal to the reproduction speaker. The compensation data has a value H/C, where H is a transfer function from the reference speaker to a control point located in the vicinity of an ear of the listener, and C is a transfer function from the reproduction speaker to the control point located in the vicinity of the ear of the listener.
    Type: Application
    Filed: September 19, 2001
    Publication date: May 2, 2002
    Inventors: Kenichi Terai, Hiroyuki Hashimoto, Isao Kakuhari
  • Patent number: 6370256
    Abstract: An apparatus for implementing a Head Related Transfer Function on an input audio signal in a headtracked listening environment comprising: a series of principle component filters attached to the input audio signal and each outputting a predetermined simulated sound arrival; a series of delay elements each attached to a corresponding one of the principle component filters and delaying the output of the filter by a variable amount depending on a delay input so as to produce a filter delay output; a summation means interconnected to the series of delay elements and summing the filter delay outputs to produce an audio speaker output signal; headtrack parameter mapping unit having a current orientation signal input and interconnected to each of the series of delay elements so as to provided the delay inputs.
    Type: Grant
    Filed: March 31, 1999
    Date of Patent: April 9, 2002
    Assignee: Lake DSP Pty Limited
    Inventor: David Stanley McGrath
  • Publication number: 20020034307
    Abstract: M (M is in the plural) sound source signals T1, T2, T3, T4, each having at least one information of position information, movement information and localization information, are synthesized to N sound source signals SL, SR based on this information where N is smaller than the number (M) of the sound source signals and N synthesized sound source signals SL, SR having this synthesized information are localized in virtual sound image An amount of data to be processed can be reduced while virtual reality can be realized by sounds.
    Type: Application
    Filed: August 1, 2001
    Publication date: March 21, 2002
    Inventor: Kazunobu Kubota
  • Publication number: 20020025054
    Abstract: An object is to enable accurate calculation of angles and displacements, and to enable reduction of circuit scales. An audio signal processing device, having a digital signal processing circuit (31) which performs virtual acoustic image localization processing such that an acoustic image is localized at an arbitrary position in the vicinity of the listener, by reproducing, using headphones (2) or a plurality of speakers, output signals obtained by signal processing of input audio signals, is characterized in that analog detection signals from a sensor (1) which detects the state of action of the listener are input to the digital signal processing circuit (31) via an A/D converter (30), and the transmission characteristics of these audio signals are modified in realtime, according to values derived by processing the values of analog detection signals from the sensor (1), or by processing the analog detection signals.
    Type: Application
    Filed: July 24, 2001
    Publication date: February 28, 2002
    Inventors: Yuji Yamada, Hirofumi Kurisu
  • Publication number: 20020025047
    Abstract: The invention relates to a system for generating sounds with a left front loudspeaker which converts an electric signal of a left audio channel and with a right front loudspeaker which converts an electric signal of a right audio channel. Such a system for generating sounds in a room is known. The electric signals are processed such that spatial rear loudspeakers are dispensed with and the front loudspeakers generate a surround or spatial sound. According to the invention, a virtual filter generates virtual sound bodies laterally of a listener in a region between 80 and 100 degrees. Experiments have shown that the human ear is most sensitive to surrounding sound when sound sources are arranged laterally of a listener's head or when spatial sound is generated laterally of a listener.
    Type: Application
    Filed: August 27, 2001
    Publication date: February 28, 2002
    Inventor: Stefan Marghuerite Jean Willems
  • Patent number: 6343130
    Abstract: A stereophonic sound processing system for localizing a sound image at desired locations using devices including a headphone and a speaker, includes a processing unit for generating stereophonic sound on the basis of an input signal. The processing unit includes: a plurality of stereophonic filter units each including an FIR filter for processing an input signal; a selecting unit for selecting one of the plurality of stereophonic filter units in accordance with a desired factor; wherein the processing unit controls the selected stereophonic filter unit so as to generate stereophonic sound on the basis of a processed result supplied by the selected stereophonic filter unit.
    Type: Grant
    Filed: February 25, 1998
    Date of Patent: January 29, 2002
    Assignee: Fujitsu Limited
    Inventor: Yasushi Yamazaki
  • Patent number: 6343131
    Abstract: A virtual acoustic environment comprises surfaces which reflect, absorb and transmit sound. Parametrisized filters are used to represent the surfaces, and parameters defining the transfer function of the filters are presented in order to represent the parametrisized filters.
    Type: Grant
    Filed: October 19, 1998
    Date of Patent: January 29, 2002
    Assignee: Nokia OYJ
    Inventor: Jyri Huopaniemi
  • Publication number: 20020006206
    Abstract: The present invention disclosed and claimed herein, in one aspect thereof, comprises a method for enhancing the front sound image during reproduction in a listening space of a stereo sound program, comprising the steps of receiving left and right channels of the stereo sound program; generating a virtual center channel signal from the left and right channels of the stereo sound program; and driving a center channel speaker with the virtual center channel signal, the center channel speaker disposed at a central location in a front portion of the listening space.
    Type: Application
    Filed: June 1, 2001
    Publication date: January 17, 2002
    Applicant: SONICS ASSOCIATES, INC.
    Inventor: William Clayton Scofield
  • Patent number: 6330486
    Abstract: A system and method for correcting discrepancies in the apparent location of audio sources in a computer representation of a three-dimensional environment is provided. The system and method compensate for distortions created by disparities between the virtual camera field of view and the observer's field of view. The system and method further provide for appropriate adjustments to audio sources outside of the observer's field of view.
    Type: Grant
    Filed: July 16, 1997
    Date of Patent: December 11, 2001
    Assignee: Silicon Graphics, Inc.
    Inventor: Thomas J. Padula
  • Publication number: 20010040968
    Abstract: A sound apparatus is constructed for directing a sound image of a virtual sound source at a designated source point to a listener in a virtual sound field. In the sound apparatus, a database provisionally memorizes acoustic transfer characteristics of the virtual sound field in correspondence to reference source points distributed radially around a center point of the listener. Left and right filters respectively filter audio signals of left and right channels according to the acoustic transfer characteristics loaded from the database. A processor computes a leftward acoustic direction from the designated source point to a left ear of the listener, and computes a rightward acoustic direction from the designated source point to a right ear of the listener.
    Type: Application
    Filed: December 10, 1997
    Publication date: November 15, 2001
    Inventor: MASAHIRO MUKOJIMA
  • Publication number: 20010031057
    Abstract: An apparatus and method for producing spatially distributed sound into a set of headphones having left and right ear-cups. An input receives a sound signal including a left channel signal, a right channel signal, a front channel signal and optionally a rear channel signal. The left and right are directly outputted by corresponding transducers in either the left or right ear-cup. The front and rear channels are each divided in two, so that they can be fed to transducers on both the left and right ear-cups. A set of headphones provided with such an apparatus is also provided.
    Type: Application
    Filed: December 26, 2000
    Publication date: October 18, 2001
    Inventor: Martin Pineau
  • Publication number: 20010021257
    Abstract: In the stereophonic sound field reproducing apparatus for reproducing a stereophonic sound field, at the time of using, a signal processing unit (4) executes a process on signals to reproduction-use minispeakers (6L1 through 6LN, 6R1 through 6RN) so as to simultaneously correct characteristics between the reproduction-use minispeakers (6L1 through 6LN, 6R1 through 6RN) and a head of a user (5) and characteristics between the reproduction-use minispeakers (6L1 through 6LN, 6R1 through 6RN), and the reproduction-use minispeakers (6L1 through 6LN, 6R1 through 6RN) arranged around the head of the user (5) input signals and output sound waves.
    Type: Application
    Filed: April 16, 2001
    Publication date: September 13, 2001
    Inventor: Toru Ishii
  • Patent number: 6269166
    Abstract: To provide a three-dimensional acoustic effect to a listener in a reproduction field, via a headphone in particular, a three-dimensional acoustic apparatus is formed by a linear synthesis filter having filter coefficients that are the linear predictive coefficients obtained by performing a linear predictive analysis on an impulse response which represents the acoustic characteristics to be added to the original signal to achieve this effect. By passing the signal through this acoustic characteristics adding filter, the desired acoustic characteristics are added to the original signal, and by dividing the power spectrum of the impulse response of these acoustic characteristics into critical bandwidths and performing this linear predictive analysis based on impulse signal determined based from power spectrum signals representing the signal sound of each of these critical bandwidths, the filter coefficients of the linear synthesis filter are determined.
    Type: Grant
    Filed: June 11, 1999
    Date of Patent: July 31, 2001
    Assignee: Fujitsu Limited
    Inventors: Naoshi Matsuo, Kaori Suzuki
  • Patent number: 6259795
    Abstract: A method for distribution multiple users of a soundfield having positional spatial components is disclosed including inputting a soundfield signal having the desired positional spatial components in a standard reference frame; applying at least one head related transfer function to each spatial component to produce a series of transmission signals; transmitting the transmission signals to the multiple users; for each of the multiple users, determining a current orientation of a current user and producing a current orientation signal indicative thereof; utilising the current orientation signal to mix the transmission signals so as to produce sound emission source output signals for playback to the user. The soundfield signal can comprise a B-format signal which is suitably processed.
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: July 10, 2001
    Assignee: Lake DSP Pty Ltd.
    Inventor: David Stanley McGrath
  • Patent number: 6225900
    Abstract: A buoyant accessory device 10 for use in a spa 100 and in conjunction with a remote piece of audio equipment 200 to produce a stereophonic effect within the spa 100. The device 10 comprises a buoyant housing member 20 containing a receiver unit 15 which is coupled in a wireless fashion to a remote transmitting unit 16 directly connected to the remote piece of audio equipment 200.
    Type: Grant
    Filed: March 24, 1997
    Date of Patent: May 1, 2001
    Inventors: David Keon, Susan Keon
  • Patent number: 6181800
    Abstract: A head related transfer function (HRTF) is used to simulate positional three-dimensional sound. The HRTF accounts for the frequency response, delays and reflections of the human body. The HRTF is unique to each individual and is affected by the shape and size of the head, the shape and size of the pinnae, the characteristics of the ear canal and the relationships of the shoulder to the ear. An HRTF for an individual is interactively approximated by first choosing a generalized HRTF. A computer, or other device, outputs audio signals from fixed locations using the generalized HRTF. Although the sound is output from fixed positions, a user may be expected to perceive the sound from a position different than the fixed position from which the sound is output. The user inputs the actual perceived position of the sound to the computer. The computer calculates positional errors between the expected perceived position of the sound and the actual perceived position of the sound.
    Type: Grant
    Filed: March 10, 1997
    Date of Patent: January 30, 2001
    Assignee: Advanced Micro Devices, Inc.
    Inventor: J. Andrew Lambrecht
  • Patent number: 6178245
    Abstract: A system produces, based on samples of a single-channel input audio signal and an indication of a particular orientation of the listener relative to a source of the audio signal, a multi-channel output audio signal that emulates an audio signal as emanating from the source having the particular orientation to the listener. Interaural time delay (ITD) circuitry generates, from the single-channel input audio signal, a first left channel audio signal and a first right channel audio signal, wherein the first left channel audio signal and the first right channel audio signal are each based on the single-channel input audio signal but differ from each other at least with respect to phase based on the indication of the particular orientation. Azimuth frequency compensating (AFC) circuitry modifies the first left channel audio signal and the first right channel audio signal based on an azimuth, relative to the listener's left ear and right ear, respectively, of the particular orientation.
    Type: Grant
    Filed: April 12, 2000
    Date of Patent: January 23, 2001
    Assignee: National Semiconductor Corporation
    Inventors: David Thomas Starkey, Anthony Martin Sarain
  • Patent number: 6175631
    Abstract: A system and method are described for rendering a left rear surround input signal at a left rear virtual speaker location and rendering a right rear surround input signal at a right rear virtual speaker location. The method includes phase shifting the left rear surround input signal by a first phase shift. The right rear surround input signal is phase shifted by a second phase shift. The phase shifted left rear surround input signal is phase shifted using an HRTF selected to render the left rear surround input signal at the left rear virtual speaker location. The phase shifted right rear surround input signal is transformed using an HRTF selected to render the right rear surround input signal at the right rear virtual speaker location.
    Type: Grant
    Filed: July 9, 1999
    Date of Patent: January 16, 2001
    Inventors: Stephen A. Davis, Martin Walsh, David Berners
  • Patent number: 6169806
    Abstract: A computer including an extraction unit for extracting source signals of surround sound from data received via a medium, and a processor for decoding and converting the source signals into audio signals of a plurality of channels. The processor includes the function of correction a sound field of a plurality of speakers which are arranged approximately concentrically together with a display unit about an operating position of a user operating the computer.
    Type: Grant
    Filed: February 4, 1997
    Date of Patent: January 2, 2001
    Assignee: Fujitsu Limited
    Inventors: Shinta Kimura, Yasuo Sato
  • Patent number: 6144747
    Abstract: A head mounted surround sound virtual positioning system that includes a video recorder (200), which is operable to have disposed therein a tape (202), having a surround sound audio track associated therewith. The surround sound system is encoded on two channels, which are output to a Dolby.RTM. decoder (204), which is operable to extract the five surround sound system channels therefrom. The left front, left rear, right front and right rear channels are input to a virtual positioning system (264), which is operable to virtually position each of the speakers relative to the head of the listener (26). These signals are then combined with a combining circuit (268) to provide the virtual positioning of only two speaker lines (58) and (60), disposed adjacent the right and left ears of the listener (26). The speakers (58) and (60) are disposed on the head mounted system such that they are fixed relative to, the ear of the listener and slightly forward of the ears and adjacent the head.
    Type: Grant
    Filed: November 24, 1998
    Date of Patent: November 7, 2000
    Assignee: Sonics Associates, Inc.
    Inventors: William Clayton Scofield, Stevan Otha Saunders
  • Patent number: 6125115
    Abstract: A computer network teleconferencing system is provided in which audio signals are coupled to or associated with source indicators, such as source addresses in TCP protocol packets. Three-dimensional spatialization transforms are applied to audio data according to the source of such data so that, upon reproduction, a listener perceives different participants as being located in different spaced-apart locations within a 3-D spatialization region. Preferably, the user may select or modify the apparent location of the teleconference participants.
    Type: Grant
    Filed: February 12, 1998
    Date of Patent: September 26, 2000
    Assignee: QSound Labs, Inc.
    Inventor: Gerard Dirk Smits
  • Patent number: 6118875
    Abstract: A method and apparatus for simulating the transmission of sound from sound sources to the ear canals of a listener encompasses novel head-related transfer functions (HTFs), novel methods of measuring and processing HTFs, and novel methods of changing or maintaining the directions of the sound sources as perceived by the listener. The measurement methods enable the measurement and construction of HTFs for which the time domain descriptions are surprisingly short, and for which the differences between listeners are surprisingly small. The novel HTFs can be exploited in any application concerning the simulation of sound transmission, measurement, simulation, or reproduction. The invention is particularly advantageous in the field of binaural synthesis, specifically, the creation, by means of two sound sources, of the perception in the listener of listening to sound generated by a multichannel sound system.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: September 12, 2000
    Inventors: Henrik M.o slashed.ller, Dorte Hammersh.o slashed.i, Clemen Boje Jensen, Michael Friis S.o slashed.rensen
  • Patent number: 6108430
    Abstract: A signal processing circuit for performing predetermined signal processes to input audio signals of four channels, headphones to which an output signal of the signal processing circuit is supplied, and detecting method for detecting a rotation of the head of the listener are provided. Digital filters for convoluting impulse responses obtained by converting head portion transfer functions from sound sources to the right and left ears into time regions to the input audio signals of four channels, time-difference adding circuits, and level-difference adding circuits are provided in the signal processing circuit. In the adding circuits, a time difference and a level difference of the signals which are transmitted through the adding circuits are controlled in accordance with detection outputs of the detecting method.
    Type: Grant
    Filed: September 30, 1999
    Date of Patent: August 22, 2000
    Assignee: Sony Corporation
    Inventor: Hirofumi Kurisu
  • Patent number: 6021206
    Abstract: The invention relates to an apparatus for sound reproduction of a sound information signal having spatial components, the apparatus includes:sound input means adapted to input the sound information signal;headtracking means for tracking a current head orientation of a listener listening to the sound information signal via sound emission sources and to produce a corresponding head orientation signal;sound information rotation means connected to the sound input means and the headtracking means and adapted to rotate said sound information signal to a substantially opposite degree to the degree of orientation of said current head orientation of the listener to produce a rotated sound information signal; andsound conversion means connected to the sound information rotation means for converting the rotated sound information signal to corresponding sound emission signals for outputting by the sound emission sources such that the spatial components of the sound information signal are substantially maintained in the p
    Type: Grant
    Filed: October 2, 1996
    Date of Patent: February 1, 2000
    Assignee: Lake DSP Pty Ltd
    Inventor: David Stanley McGrath
  • Patent number: 6021205
    Abstract: A headphone device having the function of detecting the head turning angle, in which attempts to realize sound image localization in the forward direction and that in the rear direction simultaneously does not result in the impulse response processing becoming voluminous. If a headphone 7 experiences a rotary movement, a rotational angular velocity sensor 8, mounted on a headband 7a, outputs a voltage proportionate to the angular velocity. The output voltage is filtered by a bandwidth limiting filter 9 and encoded by an A/D converter 10 to enter a micro-processor 11. The output signal of the A/D converter 10, entering the micro-processor 11, is sampled at a pre-set time interval and integrated so as to be converted into angular data. A rotational angle for actually localizing the sound image is calculated from the angular data and corresponding signal processing data is transmitted to a digital signal processing circuit 4.
    Type: Grant
    Filed: August 20, 1996
    Date of Patent: February 1, 2000
    Assignee: Sony Corporation
    Inventors: Yuji Yamada, Kiyofumi Inanaga
  • Patent number: 5987142
    Abstract: A sound spatialization including, for each monophonic channel to be spatialized, a binaural processor with two paths of convolution filters linearly combined in each path, this processor or these processors being connected to an orienting device for the computation of the spatial localization of the sound sources, the device itself being connected to at least one localizing device. The convolution is done between the monophonic signal and the user's <<left ear>> and <<right ear>> transfer functions, these transfer functions being proper to this user. This improves the efficiency of the system in localizing the monophonic sound source.
    Type: Grant
    Filed: February 11, 1997
    Date of Patent: November 16, 1999
    Assignee: Sextant Avionique
    Inventors: Maite Courneau, Christian Gulli, Gerard Reynaud
  • Patent number: 5974152
    Abstract: A sound image localization control device reproduces an acoustic signal on the basis of a plurality of simulated delay times and a plurality of simulated filtering characteristics as if a sound image ware located on an arbitrary position other than positions of separately arranged transducers. A convolver which is main device of the sound image localization control device comprise of a plurality of delay elements having the plurality of simulated delay times for delaying an audio signal to constitute a direct sound signal and a plurality of reflection sound signals. And the convolver includes a plurality of Infinite Impulse Response filters for filtering the direct sound signal and the plurality reflection sound signals on the basis of the plurality of simulated filtering characteristics respectively.
    Type: Grant
    Filed: February 13, 1997
    Date of Patent: October 26, 1999
    Assignee: Victor Company of Japan, Ltd.
    Inventor: Yoshihisa Fujinami
  • Patent number: 5949894
    Abstract: A sound reproduction system comprises a plurality of loudspeakers (S1, S2) spaced from a listener at a location (M1, M2), and a loudspeaker drive means (H) for driving the loudspeakers (S1, S2) in response to a plurality of channels of a sound recording (x) of the type being suitable for playing normally through a plurality of reference speakers that are optimally positioned at locations that are displaced from the actual positions of the loudspeakers (S1, S2). The loudspeaker drive includes a filter (H), having a filter characteristic selected by minimising the difference between a desired sound field that would be created by playing the unfiltered sound recording (x) through the reference speakers and sound field reproduced at the listener location (M1, M2) by playing the recording through the speakers (S1, S2).
    Type: Grant
    Filed: March 18, 1997
    Date of Patent: September 7, 1999
    Assignee: Adaptive Audio Limited
    Inventors: Philip Arthur Nelson, Felipe Orduna-Bustamante, Hareo Hamada
  • Patent number: 5870481
    Abstract: A method and apparatus to enhance or improve the sound localization properties of hearing aids determines the interaural level differences required for localizing sounds to a specific point of origin. These determined interaural level differences are then used in the adjusting and fitting of the hearing aids. A number of hearing tests at different frequencies with a sound source that apparently moves relative to the test subject are performed, and by adjusting the response of the hearing aid in the left ear relative to the right ear, for example by attenuating the left ear, the amount of attenuation or gain can be found that causes the test subject to perceive that the sound source is located at a specific point of origin. These determined interaural level differences are then used to design a new hearing aid or to modify the existing hearing aid.
    Type: Grant
    Filed: September 25, 1996
    Date of Patent: February 9, 1999
    Assignee: QSound Labs, Inc.
    Inventors: Robin Norman Dymond, Abram Gamer
  • Patent number: 5841879
    Abstract: A sound system has a receiver (204) for receiving individual decoded speaker signals comprised of three independent speaker signals (226) for driving associated speakers (208-214) disposed in predetermined relative positions about the listener. Head mounted speakers (58, 50) are fixed in position relative to the head (26) of the listener. A virtual positioning system (264) receives and then positions the three individual decoded signals (226) from the receiver (204) relative to the listener as virtually positioned speaker signals (266) representative of the predetermined relative positions of the associated speakers. The virtually positioned speaker signals (266) are transmitted proximate to the right and left ears (66, 68) of the listener through the right and left head mounted speakers (58, 60), but are actually perceived by the listener as being at the predetermined relative positions of the three independent speaker signals and their associated speakers (208-214).
    Type: Grant
    Filed: April 2, 1997
    Date of Patent: November 24, 1998
    Assignee: Sonics Associates, Inc.
    Inventors: William Clayton Scofield, Stevan Otha Saunders