Virtual meeting rooms with spatial audio
View Patent ↗A system for conducting a virtual audio-visual conference between two or more users comprising two or more client stations each acting as a signal source and destination for each respective user, having a user interface for audio-visual input and output including audio signal reception and generation means for receiving and generating audio signals, one or more servers, and a network coupling the client stations and the servers, wherein each user is represented as a corresponding movable visual symbol displayed on the user interfaces of all coupled client stations and the audio signal of all users is generated at each client station with an attenuation according to the spatial position of the respective symbols on the user interfaces and according to the direction in which each movable visual symbol of each signal source is oriented on the user interface.
1. A system for conducting a virtual audio-visual conference between two or more users comprising:
two or more client stations each acting as a signal source and destination for each respective said user, having a user interface for audio-visual input and output including audio signal reception and generation means for receiving and generating audio signals,
one or more servers; and
a network coupling said client stations and said servers; wherein each said user is represented as a corresponding movable visual symbol displayed on said user interfaces of all coupled said client stations, and said audio signal of all said users is generated at each said client station with an attenuation according to the spatial position of respective said symbols on said user interfaces and according to the direction in which each movable visual symbol of each signal source is oriented on the user interface,
wherein said attenuation of said audio signal according to spatial position is determined according to the formula:
1
λ
(
(
x
R
-
x
S
)
2
+
(
y
R
-
y
S
)
2
)
+
1
where (X S , Y S ) is the spatial position of said signal source and (X R , Y R ) is the spatial position of said signal destination and λ is the parameter of how fast the signal decays.
2. The system of claim 1 wherein said attenuation according to the direction is further approximated by an ellipse defined by an original of said sound source at a point a which coincides with a focus of said ellipse, a forward range max, a backward range min and said direction in which said movable visual symbol of each said signal source is oriented is the unit vector u a as measured from the (x, y).
3. A system for conducting a virtual audio-visual conference between two or more users comprising:
two or more client stations each acting as a signal source and destination for each respective said user, having a user interface for audio-visual input and output including audio signal reception and generation means for receiving and generating audio signals,
one or more servers; and
a network coupling said client stations and said servers; wherein each said user is represented as a corresponding movable visual symbol displayed on said user interfaces of all coupled said client stations, and said audio signal of all said users is generated at each said client station with an attenuation according to the spatial position of respective said symbols on said user interfaces and according to the direction in which each movable visual symbol of each signal source is oriented on the user interface,
wherein said attenuation according to the direction is further approximated by an ellipse defined by an original of said sound source at a point a which coincides with a focus of said ellipse, a forward range max, a backward range min and said direction in which said movable visual symbol of each said signal source is oriented is the unit vector u a as measured from the (x, y).
4. The system of claim 3 wherein said attenuation according to the direction is further determined according to the formula:
1
1
+
(
N
a
-
1
)
(
b
-
a
)
(
b
-
a
)
r
(
max
a
,
min
a
,
π
-
ω
)
2
where:
b is said sound destination point,
u a forms an angle φ with the vector (−1,0),
N a is the parameter on how fast the signal decays,
ω
=
arccos
(
b
-
a
)
u
A
(
b
-
a
)
(
b
-
a
)
,
and
r
(
max
,
min
,
ϕ
)
=
2
max
min
max
+
min
+
(
max
+
min
)
cos
ϕ
.
5. A method of conducting a virtual audio-visual conference between two or more users, each user having a user interface for audio-visual input or output including audio signal reception and generation means for receiving and generating audio signals, said method comprising the steps of:
representing each user as a movable symbol displayed on said user interface;
locating the position of a sound generating participant in said virtual conference;
locating the position of a listening participant in said virtual conference;
calculating the signal strength of said signal received from said generating participant at the position of said listening participant in said virtual conference based upon the distance between said sound generating participant and said listening participant in said virtual conference and upon the direction in which the sound generating participant is oriented in said virtual conference; and
generating an output signal corresponding to said calculated signal strength,
wherein said calculated signal strength based upon distance is determined with a uniform attenuation from said sound generating participant in said virtual conference, and
wherein said attenuation is determined according to the formula:
1
λ
(
(
x
R
-
x
S
)
2
+
(
y
R
-
y
S
)
2
)
+
1
where (X S , Y S ) is said position of said sound generating participant and (X R , Y R ) is said position of said listening participant and λ is the parameter on how fast said signal strength decays.
6. The method of claim 5 wherein said calculated signal strength based upon direction is determined with an attenuation that is approximated by an ellipse defined by an origin of said sound generating participant in said virtual conference at a point a which coincides with a focus of said ellipse, a forward range max, a backward range min and said direction in which said sound generating participant is oriented in said virtual conference is the unit vector u a as measured from the (x,y) axis of said virtual conference.
7. A method of conducting a virtual audio-visual conference between two or more users, each user having a user interface for audio-visual input or output including audio signal reception and generation means for receiving and generating audio signals said method comprising the steps of:
representing each user as a movable symbol displayed on said user interface;
locating the position of a sound generating participant in said virtual conference;
locating the position of a listening participant in said virtual conference;
calculating the signal strength of said signal received from said generating participant at the position of said listening participant in said virtual conference based upon the distance between said sound generating participant and said listening participant in said virtual conference and upon the direction in which the sound generating participant is oriented in said virtual conference; and
generating an output signal corresponding to said calculated signal strength,
wherein said calculated signal strength based upon direction is determined with an attenuation that is approximated by an ellipse defined by an origin of said sound generating participant in said virtual conference at a point a which coincides with a focus of said ellipse, a forward range max, a backward range min and said direction in which said sound generating participant is oriented in said virtual conference is the unit vector u a as measured from the (x,y) axis of said virtual conference.
8. The method of claim 7 wherein said attenuation that is approximated by an ellipse is further determined according to the formula:
1
1
+
(
N
a
-
1
)
(
b
-
a
)
(
b
-
a
)
r
(
max
a
,
min
a
,
π
-
ω
)
2
where:
b is said position of said sound generating participant,
u a forms an angle φ with the vector (−1,0),
N a is the parameter on how fast the signal decays,
ω
=
arccos
(
b
-
a
)
u
A
(
b
-
a
)
(
b
-
a
)
,
and
r
(
max
,
min
,
ϕ
)
=
2
max
min
max
+
min
+
(
max
+
min
)
cos
ϕ
.
9. A method for generating a spatial audio signal in a virtual conference presented on a audio-visual device comprising the steps of:
locating the position of a sound generating participant in said virtual conference;
locating the position of a listening participant in said virtual conference;
calculating the signal strength of said signal received from said generating participant at the position of said listening participant in said virtual conference based upon the distance between said sound generating participant and said listening participant in said virtual conference and based upon the direction in which said sound generating participant is oriented in said virtual conference, and
generating an output signal corresponding to said calculated signal strength,
wherein said calculated signal strength based upon distance is determined with a uniform attenuation from said position of said sound generating participant in said virtual conference, and
wherein said attenuation is determined according to the formula:
1
λ
(
(
x
R
-
x
S
)
2
+
(
y
R
-
y
S
)
2
)
+
1
where (X S , Y S ) is said position of said sound generating participant and (X R , Y R ) is said position of said listening participant and λ is the parameter of how fast said signal strength decays.
10. A method for generating a spatial audio signal in a virtual conference presented on a audio-visual device comprising the steps of:
locating the position of a sound generating participant in said virtual conference;
locating the position of a listening participant in said virtual conference;
calculating the signal strength of said signal received from said generating participant at the position of said listening participant in said virtual conference based upon the distance between said sound generating participant and said listening participant in said virtual conference and based upon the direction in which said sound generating participant is oriented in said virtual conference, and
generating an output signal corresponding to said calculated signal strength,
wherein said calculated signal strength based upon direction is determined with an attenuation that is approximated by an ellipse defined by an origin of said sound generating participant in said virtual conference at a point a which coincides with a focus of said ellipse, a forward range max, a backward range min and said direction in which said sound participant is oriented in said virtual conference is the unit vector u a as measured from the (x, y) axis.
11. The method of claim 10 wherein said attenuation that is approximated by an ellipse is further determined according to the formula:
1
1
+
(
N
a
-
1
)
(
b
-
a
)
(
b
-
a
)
r
(
max
a
,
min
a
,
π
-
ω
)
2
where:
b is said position of said generating participant,
u a forms an angle φ with the vector (−1,0),
N a is the parameter on how fast the signal decays,
ω
=
arccos
(
b
-
a
)
u
A
(
b
-
a
)
(
b
-
a
)
,
and
r
(
max
,
min
,
ϕ
)
=
2
max
min
max
+
min
+
(
max
+
min
)
cos
ϕ
.
12. A system for conducting a virtual audio-visual conference between two or more users comprising:
two or more client stations each acting as a signal source and destination for each respective said user, having a user interface for audio-visual input and output including audio signal reception and generation means for receiving and generating audio signals,
one or more servers; and
a network coupling said client stations and said servers; wherein each said user is represented as a corresponding movable visual symbol displayed on said user interfaces of all coupled said client stations, and said audio signal of all said users is generated at each said client station with an attenuation according to the spatial position of respective said symbols on said user interfaces and according to the direction in which each movable visual symbol of each signal source is oriented on the user interface,
wherein said attenuation of said audio signal according to spatial position is determined uniformly from said spatial position of each said signal source, and
wherein said attenuation according to the direction is further approximated by an ellipse defined by an original of said sound source at a point a which coincides with a focus of said ellipse, a forward range max, a backward range min and said direction in which said movable visual symbol of each said signal source is oriented is the unit vector u a as measured from the (x, y).
13. A method of conducting a virtual audio-visual conference between two or more users each user having a user interface for audio-visual input or output including audio signal reception and generation means for receiving and generating audio signals, said method comprising the steps of:
representing each user as a movable symbol displayed on said user interface;
locating the position of a sound generating participant in said virtual conference;
locating the position of a listening participant in said virtual conference;
calculating the signal strength of said signal received from said generating participant at the position of said listening participant in said virtual conference based upon the distance between said sound generating participant and said listening participant in said virtual conference and upon the direction in which the sound generating participant is oriented in said virtual conference; and
generating an output signal corresponding to said calculated signal strength,
wherein said calculated signal strength based upon distance is determined with a uniform attenuation from said sound generating participant in said virtual conference, and
wherein said calculated signal strength based upon direction is determined with an attenuation that is approximated by an ellipse defined by an origin of said sound generating participant in said virtual conference at a point a which coincides with a focus of said ellipse, a forward range max, a backward range min and said direction in which said sound generating participant is oriented in said virtual conference is the unit vector u a as measured from the (x,y) axis of said virtual conference.