Discrete dynamic positioning of audio signals in a 360.degree. environment

• US 5,850,455 A
• Filed: 06/18/1996
• Issued: 12/15/1998
• Est. Priority Date: 06/18/1996
• Status: Expired due to Fees

• Current Assignee: Extreme Audio Reality Incorporated
• Original Assignee: Extreme Audio Reality Incorporated
• Inventors: Bates, Daniel, Arnold, Glenn
• Primary Examiner(s): CHIN, VIVIAN C
• Application Number:
  US08/665,515
• Time in Patent Office: 910 Days
• Field of Search: 381/17, 381/18, 381/104, 381/24, 381/1, 381/19, 381/20
• US Class Current: 381/17
• CPC Class Codes: G11B 2220/2537 Optical discs
• CPC Class Codes: H04S 2400/11 Positioning of individual sound objects, e.g. moving airplane, within a sound field H04S2420/13 takes precedence
• CPC Class Codes: H04S 3/00 Systems employing more than two channels, e.g. quadraphonic H04S5/00, H04S7/00 take precedence
• CPC Class Codes: H04S 7/301 Automatic calibration of stereophonic sound system, e.g. with test microphone
• CPC Class Codes: H04S 7/302 Electronic adaptation of stereophonic sound system to listener position or orientation H04S7/301 takes precedence
• CPC Class Codes: H04S 7/40 Visual indication of stereophonic sound image

Abstract

A software algorithm is disclosed which allows audio signals to be positioned discretely and dynamically in a 360° environment, the center of which is assumed to be the position of the user-listener. The algorithm includes: a) proprietary knowledge of the sound sources (such as a synthesizer chip); b) proprietary knowledge of the number of independently addressable couplers (i.e. how many speakers are employed); and c) a software driver incorporated on a host, computer, or a stand-alone device which includes the algorithm for routing the sound sources to the transducers at the proper volume levels. In a preferred embodiment of the invention, the algorithm functions by controlling the amplitude attenuation of each source as it is coupled to the transducers, and the relationship of the amplitudes sent to each transducer by means of reference values contained in a matrix table native to the algorithm. By changing the amplitude attenuations in accordance with the table of values, the perceptual location of each source can be changed within the 360° environment, such that the listener is immersed within the audio environment. The method of the invention, and the matrix operating therewith, will be seen to simplify computer programming for a surround sound environment, and with user-listener interaction thereof.

Claims

1. A method for dynamically positioning audio signals in an environment comprising the steps of:

receiving audio coordinate values for the outputs of a given sound source;

providing a matrix of values defining individual spatial positions within said environment;

comparing said coordinate values with said matrix of values to provide attenuated amplitude levels for sound source outputs; and

mixing signals from said sound source outputs through a coupler to four transducers to be reproduced thereat, wherein different attenuated amplitude levels apply to each of said four transducers.

2. The method of claim 1, also including the step of:

locating a user-listener within said environment, with said transducers around said user-listener.

3. The method of claim 2, wherein said step of providing a matrix of values provides a matrix of values to include a table of attenuation values for each of said sound source outputs.

4. The method of claim 2, wherein said step of receiving audio coordinate values receives audio coordinate values for a minimum of 4 outputs of a given sound source simultaneously, and at varying levels.

5. The method of claim 2, wherein said steps of receiving audio coordinate values, providing a matrix of values, comparing said coordinate values, and mixing signals are performed in a software program.

6. The method of claim 2, wherein said step of receiving audio coordinate values receives audio coordinate values as provided by a computer program.

7. The method of claim 2, wherein said step of receiving audio coordinate values receives audio coordinate values as provided by a computer program in which each coordinate value can be continuously adjusted by said user-listener.

8. The method of claim 2, wherein said step of providing a matrix of values provides a matrix of values from 0 to N-1, where "0" represents a location on a circle behind a listener of said reproduced audio output signals and where 1/2N represents a location on said circle in front of said listener.

9. The method of claim 2, wherein said step of receiving audio coordinate values receives audio input signals as a data stream, where said step of comparing said coordinate values separates said data stream into separate component streams, attenuates the amplitude parameters of each component stream, adds any additional sound information into the appropriate streams, and re-combines the amplitude attenuated component streams along with the added information, into a single data stream, and wherein said step of mixing signals includes a step of surround sound processing in coupling said output signals to said transducers.

10. A method for discretely and dynamically positioning audio signals in a 360°

environment comprising the steps of;

First, receiving audio coordinate values for the outputs of a given sound source;

Second, providing a matrix of values defining individual spatial positions within said 360°

environment;

Third, comparing said coordinate values with said matrix of values to provide attenuated amplitude levels for sound source outputs; and

Fourth, mixing signals from said sound source outputs through independently controllable couplers to a plurality of transducers to be reproduced thereat;

Fifth, locating a user-listener within said 360°

environment, at the center of said plurality of transducers, wherein said first step receives audio input signals as a data stream, where said third step separates said data stream into separate component streams, attenuates the amplitude parameters of each component stream, adds any additional sound information into the appropriate streams, and re-combines the amplitude attenuated component streams along with the added information, into a single data stream, and wherein said fourth step includes a sixth step of surround sound processing in coupling said output signals to said transducers.

11. An apparatus for dynamically positioning sound sources about a field comprising:

a matrix of N values, which corresponds to levels of amplitude attenuation for coordinate values, in providing audio output signals to a coupler for signal processing to dynamically and individually spatially position sound sources about a field surrounding a user-listener, wherein said coordinate values are compared with said matrix of N values to provide said levels of amplitude attenuation, wherein four transducers are provided with individually processed audio output signals for reproducing sound thereat, wherein different attenuated amplitude levels apply to each of said four transducers.

12. The matrix of claim 11 where N=128.

13. The matrix of claim 11 for spatially positioning said sound sources about said field equidistant from assumed position of said user-listener.

14. The matrix of claim 11 for spatially positioning said sound sources about said field, and of pre-selected distance from said assumed position of said user-listener.

15. The matrix of claim 11 wherein said matrix is incorporated in a software program.

16. The matrix of claim 11 wherein said field is a 360°

field.

17. The matrix of claim 16 wherein said coupler comprises at least 4 couplers.

18. The matrix of claim 17 wherein said user-listener is located at a center of said field.