JP2022125686A - Object-based acoustic rendering device and program - Google Patents

Abstract

To generate a driving signal expressing the perspective of the distance of a sound source based on WFS without expanding the scale of the system.SOLUTION: A signal amplifier 9-l of an object-based acoustic rendering device 1 amplifies a sound source signal S, and HPF 10-l performs filtering processing on the amplified signal by using HPFh(rl,rS). An attenuation addition unit 11-l multiplies the filtered signal by an attenuation coefficient 1/||rl-rS||2. An area element adder 12-l multiplies the signal multiplied by the attenuation adder 11-l by an area element ΔSl. An angle weight adder 13-l sets an angle weight wC(θl) based on an intersection angle θl between a vector (rl-rS) connecting the position of a virtual sound source 104 to the position of a speaker 106-1 and a boundary surface inward normal vector n(rl), and multiplies the signal multiplied by the area element adder 12-l by the angle weight wC(θl) to generate a driving signal d(rl).SELECTED DRAWING: Figure 1

Description

The present invention relates to an object-based sound reproduction device, and more particularly to an object-based sound rendering device and program for calculating speaker drive signals based on the concept of WFS (Wave Field Synthesis).

In recent years, object-based sound technology has been attracting attention, mainly for movie sound. In the past, channel-based audio, in which multiple audio materials were mixed down into a specified channel format and recorded, was the mainstream.

In object-based audio, each audio material is separately recorded as an audio object, and rendering is performed based on audio metadata describing the level and coordinates of the audio object.

Hereinafter, such an object-based audio system reproducing apparatus will be referred to as an object-based audio rendering apparatus. An object-based acoustic rendering device renders an acoustic object based on acoustic metadata and the positions of a plurality of arranged speakers, and generates drive signals corresponding to the positions of the respective speakers. Acoustic reproduction according to the environment is performed. Therefore, even when the content is reproduced with a speaker arrangement different from that at the time of production, reproduction adapted to it is possible.

[VBAP]
Conventionally, an algorithm called VBAP (Vector Based Amplitude Panning) is often used for object-based audio rendering (see Non-Patent Document 1, for example).

In VBAP, the reproduction space is divided into triangular regions composed of three speakers, and weights are calculated for the speakers positioned at each vertex of the triangle containing the sound source coordinates. Then, amplitude panning is performed by distributing the sound source signal with the calculated weight.

However, in VBAP, processing is performed assuming that the loudspeakers are arranged on a spherical surface with a certain radius and the sound sources are arranged on the spherical surface. Therefore, it is not possible to express perspective based on the distance of the sound source.

When expressing a sound field including perspective using VBAP, distance attenuation and reverberation are sometimes added (see, for example, Non-Patent Document 2), which are based on psychoacoustics. It is a method, not a method for the purpose of physically reproducing a sound field.

Further, according to the VBAP weight calculation algorithm, weights are calculated assuming listening at the sweet spot, so reproduction quality is not guaranteed when auditioning at a position away from the sweet spot.

[WFS]
On the other hand, a technique called WFS is known as a method of representing a sound field based on wave acoustics. WFS is a sound field reproduction technique that is wave-acoustically backed by the Kirchhoff-Helmholtz integral equation expressed by the following equation (see, for example, Non-Patent Document 3).

where p(r) denotes the sound pressure at an arbitrary point r within some region V enclosed by the boundary ∂V, and G(r|r _o ) is the sound pressure from the point r _o on the boundary ∂V Denote the Green's function up to any point r within the boundary ∂V. n(r _o ) denotes the normal inward unit vector of the boundary ∂V at point r _o . p(r _o ) indicates the sound pressure at point r _o on boundary ∂V, and ∂p(r _o )/∂n is the direction of unit vector n(r _o ) at point r _o on boundary ∂V. Shows the sound pressure gradient vector. dS _O is the infinitesimal area on the boundary ∂V.

Also, here, when the boundary has an arbitrary shape, the Green's function assuming the Neumann condition of ∂G(r|r _o )/∂n=0 is set as the boundary condition on the boundary ∂V. We then introduce the following window function a(r _o ) determined by the average sound intensity I(r _o ) at the point r _o and the unit vector n(r _o ).

This gives the following equality:

G _o (r|r _o ) denotes the free-field Green's function from point r _o to point r. The Kirchhoff-Helmholtz integral equation shows the fact that if a sound source exists outside a region, the sound field inside that region is determined by the sound pressure gradient distribution normal to the boundary surface.

In WFS, speakers are arranged densely on the boundary surface of the area where the sound field is to be reproduced, and the coordinates of the sound source (assuming a point sound source) are given, and the speaker drive signal is determined based on the Kirchhoff-Helmholtz integral equation. do.

VlLLE PULKKI, “Virtual Sound Source Positioning Using Vector Base Amplitude Panning”, J. Audio Eng. Soc., Vol. 45, No.6, June 1997 Recommendation ITU-R. BS.2127-0 Ahrens Jens, Rabenstein Rudolph, Spors Sascha, “The Theory of wave field synthesis revisited”, in 124th Conv. Audio Eng. Soc., 2008

Thus, by using WFS, the wavefront can be resynthesized inside the reproduction region, so unlike VBAP, there is no problem that reproduction quality deteriorates at points away from the sweet spot.

However, in order to precisely synthesize wavefronts using WFS, it is necessary to place speakers densely on the boundary surface, and to add elements such as filters and delays with predetermined frequency characteristics. Therefore, when WFS is used, there is a problem that the scale of the system becomes larger than that of VBAP.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made to solve the above problems. An object of the present invention is to provide an acoustic rendering device and program.

In order to solve the above problem, the object-based acoustic rendering device according to claim 1 renders a sound source object placed at a position described in acoustic metadata, thereby rendering a plurality of speakers placed in a listening environment. In an object-based acoustic rendering device that generates drive signals for each of the plurality of speakers, L is the number of the plurality of speakers, l (= 1, ..., L) is the number of the speakers, and the l-th speaker is the l-th speaker The coordinates of the virtual sound source from which the sound source signal of the 1-th speaker is output are virtual sound source coordinates _rs , the coordinates of the 1-th speaker are speaker coordinates rl, and the inward normal vector of the boundary surface at the position of the ₁ -th speaker is With n(r _l ), ΔS _l being an area element centered on the position of the l-th speaker, and d(r _l ) being the drive signal for the l-th speaker, the virtual The angle θ _l between the vector from the position of the sound source coordinate r _S to the position of the speaker coordinate r _l of the l-th speaker and the inward normal vector n(r _l ) of the boundary surface of the l-th speaker an angle calculation unit for calculating the , the sound source signal is amplified by a constant, the HPF sets HPFh(r _l , r _s ) based on the virtual sound source coordinate r _s and the speaker coordinate r _l of the first speaker, and The signal amplified by the signal amplifying unit is filtered using the _HPFh (r _l , r _s ), and the attenuation addition unit performs the above-mentioned The absolute value of the vector up to the position of the speaker coordinate r _l is obtained, and the reciprocal of the result obtained by squaring the absolute value is set as the attenuation coefficient 1/||r _l −r _S || ² , and the filtering process is performed. multiplies the signal multiplied by the attenuation coefficient ₁ /||r _l −r _S || ² , the area element addition unit multiplies the signal multiplied by the attenuation addition unit by the area element Based on the angle _θl formed by the first speaker calculated by the angle calculation unit, the first angle weighting unit determines that the absolute value of the angle _θl is 0° in the range from 0 to 1. takes a value closer to 1, and the absolute value of the angle θ _l formed is 90° is closer to 0, and the angle weight w _C (θ _l ) that takes a value of 0 when the absolute value of the formed angle θ _l is 0° or less or 90° or more is set, and the area element addition The drive signal d(r _l ) for the l-th speaker is generated by multiplying the signal multiplied by the unit by the angle weight w _C (θ _l ).

Further, the object-based acoustic rendering device of claim 2 is the object-based acoustic _rendering device of claim 1, further comprising: Based on the unit vector of the speaker direction to r _l , the three speakers including the virtual sound source inside are specified as the three VBAP (Vector Based Amplitude Panning) target speakers, and the unit vectors of the three VBAP target speakers r _n1 , r _n2 , r _n3 are obtained, and based on the unit vector of the virtual sound source direction to the virtual sound source coordinate r _S and the unit vectors r _n1 , r _n2 , r _n3 of the three speakers targeted for VBAP, Obtain the coefficients g _l =g _n1 , g _n2 , g _n3 corresponding to the three VBAP target speakers, and set the coefficient g _l = 0 corresponding to the speakers other than the three VBAP target speakers out of all the speakers. a VBAP coefficient calculator for setting and outputting the coefficient g _l ; The signal multiplied by the area element addition unit is multiplied by the coefficient g _l output by the VBAP coefficient calculation unit, and the second angle weight addition unit calculates the l-th calculated by the angle calculation unit. Based on the angle θ _l formed by the th speaker, in the range from 0 to 1, the closer the absolute value of the formed angle θ _l is to 0°, the closer the value is to 0, and the absolute value of the formed angle θ _l is 90°. An angle weight w _S (θ _l ) that takes a value closer to 1 as the angle is closer to ° and takes a value of 0 when the absolute value of the formed angle θ _l is 0° or less or 90° or more is set, and the VBAP coefficient A second drive signal is generated by multiplying the signal multiplied by the multiplication unit by the angle weight w _S (θ _l ), and the first angle weight adding unit adds the angle weight w _C (θ _l ) is set, and the signal multiplied by the area element addition unit is multiplied by the angle weight w _C (θ _l ) to generate a first drive signal, and the addition unit generates the first drive signal and The drive signal d(r _l ) for the l-th speaker is generated by adding the second drive signal.

Further, the object-based acoustic rendering apparatus of claim 3 is the object-based acoustic rendering apparatus of claim 2, wherein the VBAP coefficient multiplying section replaces the signal multiplied by the area element adding section with the sound source signal is input, and the sound source signal is multiplied by the coefficient _gl .

にて、ＨＰＦ係数ｈ_n（ｒ_l，ｒ_S）を設定し、
ｘ［ｔ］及びｙ［ｔ］を時刻ｔにおける当該ＨＰＦの入力及び出力として、入出力特性が以下の式：

となるように、前記信号増幅部により増幅された信号に対し、前記ＨＰＦ係数ｈ_n（ｒ_l，ｒ_S）を用いてフィルタ処理を施す、ことを特徴とする。 Further, the object-based acoustic rendering device of claim 4 is the object-based acoustic rendering device of any one of claims 1 to 3, wherein the HPF has a preset parameter α With filter order N and n=0, 1, . . . , N, the following equation:

to set the HPF coefficient h _n (r _l , r _s ),
Letting x[t] and y[t] be the input and output of the HPF at time t, the input/output characteristics are:

The signal amplified by the signal amplifying section is filtered using the HPF coefficient h _n (r _l , r _s ) so that:

にて減衰係数ｇ（ｒ_l，ｒ_S）を求め、前記フィルタ処理が施された信号に対し前記減衰係数ｇ（ｒ_l，ｒ_S）を乗算する、ことを特徴とする。 Further, the object-based acoustic rendering device of claim 5 is the object-based acoustic rendering device of any one of claims 1 to 4, wherein the attenuation addition unit sets preset parameters to β ₁ and β ₂ , the formula below:

and multiplying the _{filtered signal by the attenuation coefficient g(r l , r s )} .

Furthermore, a program according to claim 6 causes a computer to function as the object-based acoustic rendering device according to any one of claims 1 to 5.

As described above, according to the present invention, it is possible to generate a driving signal that expresses the distance of a sound source based on WFS without increasing the scale of the system.

1 is a block diagram showing a configuration example of an object-based acoustic rendering device of Example 1; FIG. 4 is a pseudo code showing a processing example of the object-based acoustic rendering device of Example 1; It is a block diagram which shows the structural example of an angle calculation part. It is a figure explaining the case where a speaker is sparsely arranged. FIG. 11 is a block diagram showing a configuration example of an object-based acoustic rendering device of Example 2; 10 is a pseudo code showing a processing example of the object-based acoustic rendering device of Example 2; 3 is a block diagram showing a configuration example of a VBAP coefficient calculator; FIG. FIG. 11 is a block diagram showing a configuration example of an object-based acoustic rendering device of Example 3; FIG. 11 is pseudo code showing a processing example of the object-based acoustic rendering device of Example 3; FIG. FIG. 2 is a conceptual diagram for explaining VBAP; 1 is a conceptual diagram for explaining WFS; FIG.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention is demonstrated in detail using drawing. The object-based acoustic rendering apparatus according to the first embodiment of the present invention simplifies the configuration of the WFS by approximation, thereby generating a driving signal that expresses the distance of the sound source based on the WFS without increasing the scale of the system. do. Further, the object-based acoustic rendering apparatuses of the second and third embodiments incorporate the VBAP configuration into the configuration of the first embodiment, thereby solving the problem that the drive signal becomes small when the speakers are sparsely arranged.

Before describing the object-based acoustic rendering apparatuses of the first, second, and third embodiments of the present invention, an overview of sound field reproduction techniques using VBAP and WFS will be described.

[Overview of VBAP]
First, an outline of VBAP will be described. As described above, VBAP divides the reproduction space into triangular regions consisting of three speakers, calculates weights for the speakers located at each vertex of the triangle containing the sound source coordinates, and distributes the sound source signals. This is an amplitude panning method that performs amplitude panning.

FIG. 10 is a conceptual diagram for explaining VBAP. In the xyz space, the sound receiving point 100 is the origin, and the unit vector in the direction of the virtual sound source 101 is r _nS =(x _nS , y _nS , z _nS ) ^T . In addition, among the divided triangular areas, the unit vectors in the directions of the three speakers 102-1, 102-2, and 102-3 containing the virtual sound source 101 are r _n1 =(x _n1 , y _n1 , z _n1 ) ^T ,r _n2 =(x _n2 ,y _n2 ,z _n2 ) ^T ,r _n3 =(x _n3 ,y _n3 ,z _n3 ) ^T .

ここで、Ｒ＝[ｒ_n1 ｒ_n2 ｒ_n3]^Tとする。 At this time, the unit vector r _nS in the direction of the virtual sound source 101 is the unit vector r _n1 , r _n2 , r _n3 in the directions of the speakers 102-1, 102-2, and 102-3, and the coefficient vector g=(g _n1 , g _n2 , g _n3 ) ^T is expressed as follows.

Here, let R=[r _n1 r _n2 r _n3 ] ^T .

Ｒ^-1はＲの逆行列である。 The coefficient vector g can be calculated by the following formula.

R ⁻¹ is the inverse matrix of R.

Weighting is performed using the coefficient vector g=(g _n1 , g _n2 , g _n3 ) ^T calculated by the above equation (5). By reproducing the weighted signals from the three speakers 102-1, 102-2 and 102-3, the listener can localize the sound image in the direction of the unit vector r _nS . It should be noted that the weights of all triangular speakers that do not contain the virtual sound source 101 are set to zero.

[Overview of WFS]
Next, an outline of WFS will be described. As described above, in WFS, speakers are arranged densely on the boundary surface of the area where the sound field is to be reproduced, and based on the Kirchhoff-Helmholtz integral equation of formula (1) above, the sound field is the sound field to be reproduced at the speaker position. This is a sound field reproduction method that reproduces the sound field inside the boundary surface by reproducing the normal direction sound pressure gradient of the boundary surface in the original sound field.

FIG. 11 is a conceptual diagram for explaining WFS, where (1) shows an original sound field and (2) shows a reproduced sound field.

ここで、ｋは波数である。尚、図１１の座標ｒ₁は、ｌ＝１の場合を示している。 The original sound field of (1) is formed by sound waves radiated from the sound source 103 located at a point with coordinates r _S =(x _S , y _S , z _S ) ^T outside the region C1 in the xyz space. . Sound pressure p at coordinate r _l =(x _l , y _l , z _l ) ^T on the boundary surface of region C1 at this time is represented by the following equation. l (L) indicates the number of the point of coordinate r _l and corresponds to the number (system number) of speaker 106-l, which will be described later.

where k is the wavenumber. Note that the coordinate r ₁ in FIG. 11 indicates the case of l=1.

Furthermore, the inward unit vector in the boundary normal direction (boundary surface inward normal vector) at the point of coordinates r _l =(x _l , y _l , z _l ) ^T on the boundary surface of the region C1 is n(r _l ). Let θ _l be the angle between the vector (r _l −r _s ) connecting the point with coordinates r _S and the point with coordinates r _l and the inward normal vector n(r _l ) of the boundary surface. The sound pressure gradient vector in the normal direction at the point of coordinate r _l is expressed by the following equation.

Therefore, according to the Kirchhoff-Helmholtz integral equation, the speaker array 105 discretely arranged in the reproduced sound field of (2) is driven _by the drive signal d(r _l ), a sound field in which the point sound source of the virtual sound source 104 is arranged at the point of the coordinate r _S can be reproduced inside the region C2.

Here, ΔS _l is the area (area element) of the l-th element when the boundary surface of the region C2 is divided into area elements centered on the speaker position. It takes a small value, and the more sparsely arranged, the larger the value.

In the xyz space, r _S is the coordinates (virtual sound source coordinates) of the virtual sound source 104 and r _l is the coordinates (speaker coordinates) of the l-th speaker element forming the speaker array 105 .

Also, w _C (θ _l ) is a function defined by the following equation.

[Object-based sound rendering device]
Next, the object-based acoustic rendering apparatuses of Examples 1, 2, and 3 will be described.

In the first embodiment, the virtual sound source 104 arranged _{at the position of the virtual sound source coordinate r S and} the speaker coordinate By ignoring the term e ^-jk||rl-rs|| , which represents the time delay due to the distance to the loudspeaker placed at the position r _l , we trade off an exact wavefront reproduction, , to simplify the system.

Further, in Example 1, the term jk||r _l −r _S ||+1 in the above equation (8) has a high-pass characteristic that varies depending on the distance between the virtual sound source 104 and the speaker, and this characteristic is expressed as It is approximated by a low-order high-pass filter h(r _l , r _s ) (HPF) that depends on the distance.

As a result, in the first embodiment, by simplifying the structure of the WFS by approximation, it is possible to generate a driving signal that expresses the distance of the sound source based on the WFS without increasing the scale of the system.

Moreover, in the second and third embodiments, by incorporating the VBAP configuration into the configuration of the first embodiment, in addition to the effect of the first embodiment, the problem that the drive signal becomes small when the speakers are arranged sparsely is solved. do.

[Example 1]
First, the object-based acoustic rendering device of Example 1 will be described. As described above, the first embodiment ignores the term e ^−jk||rl-rs _|| The term |r _l −r _S ||+1 is treated as an HPF, and the high-pass characteristics that change depending on the distance between the virtual sound source 104 and the loudspeaker are replaced by a low-order high-pass filter h(r _l , r _S ) (HPF).

FIG. 1 is a block diagram showing a configuration example of the object-based acoustic rendering device of the first embodiment, and FIG. 2 is pseudocode showing a processing example of the object-based acoustic rendering device of the first embodiment.

This object-based acoustic rendering device 1 includes signal amplification units 9-1 to 9-L, HPFs (high pass filters) 10-1 to 10-L, attenuation addition units 11-1 to 11-L, area element addition units 12- 1 to 12-L, angle weighting units 13-1 to 13-L, and an angle calculation unit 20. FIG. L is the number of speakers 106-1 to 106-L and also the number of systems.

Hereinafter, in the object-based acoustic rendering device 1, the configuration units corresponding to the l-th speaker 106-l (l-th system) are respectively the signal amplification unit 9-l, the HPF 10-l, the attenuation addition unit 11 -l, an area element addition unit 12-l and an angle weight addition unit 13-l. That is, the object-based acoustic rendering device 1 includes L-system signal amplifiers 9-l, HPFs 10-l, attenuation adders 11-l, area element adders 12-l, and angle weight adders 13-l, and further An angle calculator 20 is provided. l=1, . . . , L.

The overall processing of the object-based acoustic rendering device 1 will be described with reference to FIG. The object-based acoustic rendering device 1 receives the sound source signal S and the virtual sound source coordinates r _S (step S201).

For each of the speakers 106-1 to 106-L (for the system of the speaker 106-l), the object-based acoustic rendering device 1 provides the speaker coordinates r _l of the speaker 106-l, the area element ΔS _l of the speaker 106-l, and Input the boundary surface inward normal vector n(r _l ) at the position of speaker 106-l (step S202).

Here, the subscript “l” in the speaker coordinates r _l , the area element ΔS _l and the boundary surface inward normal vector n(r _l ) is the number of the speakers 106-1 to 106-L (system number).

Also, the sound source signal S is, for example, a signal broadcast from a broadcasting station, and the virtual sound source coordinates r _S are, for example, data included in acoustic metadata broadcast from the broadcasting station. The speaker coordinates r _l , area element ΔS _l and boundary surface inward normal vector n(r _l ) are, for example, data included in speaker layout information set in advance by the user who operates the object-based acoustic rendering apparatus 1. .

In this case, the object-based acoustic rendering device 1 receives the sound source signal S and the virtual sound source coordinates r _S transmitted from the broadcasting station, and the speaker coordinates r _l , the area element ΔS _l and the inward bounding plane Input the normal vector n(r _l ).

The object-based acoustic rendering apparatus 1 generates the HPF 10-l having a coefficient of a predetermined order for the speaker 106-l based on the virtual sound source coordinates r _s input in step S201 and the speaker coordinates r _l input in step S202. HPFh (r _l , r _s ) of is set (step S203).

Based on the virtual sound source coordinates r _S input in step S201 and the speaker coordinates r _l input in step S202, the object-based acoustic rendering apparatus 1 creates a relationship between the virtual sound source 104 and the speaker 106-l for the speaker 106-l. The attenuation coefficient 1/||r ₁ −r _s || ² of the attenuation adding unit 11-l is set according to the distance between them (step S204).

That is, the object-based acoustic rendering apparatus 1 obtains the absolute value ||r _l −r _S || of the vector from the position of the virtual sound source 104 to the position of the speaker 106-l, and squares the absolute value ||r _l Set the reciprocal of −r _S || ² as the damping factor 1/||r _l −r _S || ² .

For the speaker 106-l, the object-based acoustic rendering apparatus 1 uses the virtual sound source coordinate r _S input in step S201, and the speaker coordinate r _l and boundary plane inward normal vector n(r _l ) input in step S202. _{Based on} the angle _{θ l} is calculated (step S205). The formed angle θ _l is calculated by the angle calculator 20 .

The object-based acoustic rendering apparatus _{1 determines whether or not the absolute value |θ l |} , the angle weight w _C (θ _l ) is set according to the above equation (9) (step S206).

Specifically, when the object-based acoustic rendering device ₁ determines that the formed angle |θ _l | , set the angular weights w _C (θ _l )=cos θ _l . On the other hand, when the object-based acoustic rendering device ₁ determines that the angle |θ _l | Set the angle weight w _C (θ _l )=0. This angle weight w _C (θ _l ) is used in the angle weight adding section 13-l.

The angle weight w _C (θ _l ) takes a value in the range from 0 to 1. When the angle |θ _l | is 0°<|θ _l |<90°, the angle |θ _l | The closer the _angle is to ₉₀ °, the closer the value is to ₁ , and the closer to 90° is, the closer the value is to 0. takes the value of

＊は畳み込みを表す。この駆動信号ｄ（ｒ_l）は、信号増幅部９－ｌ、ＨＰＦ１０－ｌ、減衰付加部１１－ｌ、面積要素付加部１２－ｌ及び角度重み付加部１３－ｌにより算出される。 For the speaker 106-l, the object-based acoustic rendering apparatus 1 obtains a constant u (for example, u=1/2π, which may be a different value for each system), the sound source signal S input in step S201, and the virtual sound source coordinates r _S , speaker coordinates r _l and area element ΔS _l input in step S202, HPFh (r _l , r _S ) set in step S203, attenuation coefficient 1/||r _l −r set in step S204 Using _S || ² and the angle weight w _C (θ _l ) set in step S206, the drive signal d(r _l ) is calculated and output according to the following equation (step S207).

* represents convolution. This drive signal d(r _l ) is calculated by the signal amplifier 9-l, HPF 10-l, attenuation adder 11-l, area element adder 12-l, and angle weight adder 13-l.

Next, referring to FIG. 1, processing of the components of the object-based acoustic rendering apparatus 1 will be described. The signal amplifier 9-l (9-1 to 9-L) receives the sound source signal S, multiplies the sound source signal S by a constant u (eg, 1/2π), amplifies the sound source signal S, and amplifies the sound source signal S. The resulting signal is output to HPF 10-l.

The HPF 10-l (10-1 to 10-L) inputs virtual sound source coordinates r _S and speaker coordinates r _l . Then, the HPF 10-l sets HPFh(r ₁ , r _s ) having coefficients of a predetermined order, as in step S203, based on the virtual sound source coordinates r _s and the speaker coordinates r ₁ . Then, the HPF 10-l receives the amplified signal from the signal amplifier 9-l, performs filtering on the signal using HPFh(r _l , r _s ), and outputs the filtered signal. Output to the attenuation adding section 11-l.

The attenuation adding unit 11-l (11-1 to 11-L) inputs the virtual sound source coordinates r _S and the speaker coordinates r _l , and based on the virtual sound source coordinates r _S and the speaker coordinates r _l , as in step S204, Set the damping factor 1/||r _l −r _S || ² . Then, the attenuation adding unit 11-l receives the filtered signal from the HPF 10-l and multiplies the signal by an attenuation coefficient ¹ /||r _l −r _S || The signal is attenuated according to the distance between the sound source 104 and the speaker 106-l. The attenuation adder 11-l outputs the attenuated signal (attenuated signal) to the area element adder 12-l.

The area element addition unit 12-l (12-1 to 12-L) inputs the area element ΔS _l . The area element ΔS _l takes a small value when the speakers 106-l are densely arranged, and takes a large value when the speakers 106-l are sparsely arranged.

Then, the area element addition unit 12-l receives the signal to which attenuation is added from the attenuation addition unit 11-l, and multiplies the signal by the area element ΔS _l to obtain the degree of discreteness of the speaker 106-l. A signal to which an area element is added is generated accordingly. The area element adder 12-l outputs the signal with the area element added to the angle weight adder 13-l.

The angle calculator 20 inputs virtual sound source coordinates r _S , speaker coordinates r ₁ to r _L , and boundary plane inward normal vectors n(r ₁ ) to n(r _L ). Then, as in step S205, the angle calculation unit 20 calculates a vector (r _l −r _S ) is obtained, and the angle θ _l between the vector (r _l −r _S ) and the boundary surface inward normal vector n(r _l ) at the position of the speaker 106-l is calculated. The angle calculator 20 outputs the formed angles θ _l (θ ₁ to θ _L ) to the corresponding angle weight adders 13-l (13-1 to 13-L).

FIG. 3 is a block diagram showing a configuration example of the angle calculator 20. As shown in FIG. The angle calculator 20 includes calculators 30-1 to 30-L. Calculation unit 30-1 is a component that calculates angle θ ₁ formed about speaker 106-1, virtual sound source coordinate r _S , l-th speaker coordinate r ₁ and boundary surface inward normal vector Enter n(r ₁ ). Calculation unit 30-1 obtains a vector (r ₁ −r _s ) connecting the position of virtual sound source 104 and the position of speaker 106-l, and calculates the vector (r ₁ −r _s ) at the position of speaker 106-1. Calculate the angle θ ₁ formed with the inward normal vector n(r ₁ ) of the boundary surface. The calculation unit 30-1 outputs the formed angle θ ₁ to the angle weight addition unit 13-1.

Similarly, the calculation unit 30-L is a component that calculates the angle θ _L formed with respect to the speaker 106-L, and includes the virtual sound source coordinate r _S , the l=Lth speaker coordinate r _L and the boundary plane inward Input the normal vector n(r _L ). Then, the calculation unit 30-L obtains a vector (r _L −r _S ) connecting the position of the speaker 106-l from the position of the virtual sound source 104, and calculates the vector (r _L −r _S ) at the position of the speaker 106-L. Calculate the angle θ _L formed with the inward normal vector n(r _L ) of the boundary surface. The calculator 30-L outputs the formed angle θ _L to the angle weighting unit 13-L.

Similar processing is performed for the calculation units 30-2 to 30-(L-1), and a vector (r ₂ to r _L-1 −r _S ) and the inward normal vectors n(r ₂ ) to n(r _L-1 ) of the boundary planes at the positions of the speakers 106-2 to 106-(L-1) form angles θ ₂ to θ _L-1 are calculated respectively.

Returning to FIG. 1, the angle weighting unit 13-l (13-1 to 13-L) inputs the angle θ _l (θ ₁ to θ _L ) formed from the angle calculation unit 20, and based on the formed angle θ _l Then, in step S206, the angle weight w _C (θ _l ) is set using the above equation (9). Then, the angle weight addition unit 13-l receives the signal to which the area element is added from the area element addition unit 12-l, and multiplies the signal by the angle weight w _C (θ _l ) to obtain the formed angle Generate a signal reflecting _θl .

The signal reflecting the formed angle θ _l becomes closer to the signal to which the area element is added as the formed angle θ _l is closer to 0°. On the other hand, the signal reflecting the formed angle θ _l approaches 0 as the formed angle θ _l approaches 90°.

The angle weighting unit 13-l outputs a signal reflecting the formed angle θ _l to the speaker 106-l as the driving signal d(r _l ).

1 and 2 show the configuration and processing of object-based acoustic rendering for the sound source signal S of one acoustic object, but in reality, processing is performed on the sound source signals S of a plurality of acoustic objects. . In this case, the drive signal d(r _l ) generated for each sound object is added for each speaker 106-l, and the drive signal resulting from the addition is output to the speaker 106-l. The same applies to FIGS. 5 and 6 (Example 2) and FIGS. 8 and 9 (Example 3) which will be described later.

As described above, according to the object-based acoustic rendering apparatus ₁ of the first embodiment, e ^{−jk ||} Ignore the term ^rl−rs|| and replace the term jk||r _l −r _S ||+1 with a low-order high-pass filter h(r _l , r _s ) (HPF).

Specifically, the signal amplification unit 9-l amplifies the sound source signal S by multiplying the sound source signal S by a constant u (which may be a different value for each system). The HPF 10-l sets HPFh(r ₁ , r _s ) having coefficients of a predetermined order based on the virtual sound source coordinates r _s and the speaker coordinates r ₁ . Then, the HPF 10-l filters the signal amplified by the signal amplifier 9-l using HPFh(r _l ,r _s ).

The attenuation addition unit 11-l sets an attenuation coefficient 1/||r ₁ −r _s || ² based on the virtual sound source coordinates r _S and the speaker coordinates r ₁ . Then, attenuation adding section 11-l multiplies the filtered signal by attenuation coefficient ¹ /||r _l −r _S || generates a signal that is attenuated according to the distance of

The area element addition unit 12-l multiplies the attenuated signal by the area element ΔS _l of the speaker 106-l to generate a signal with an area element added.

The angle calculation unit 20 calculates a vector (r _l −r _S ) connecting the position of the virtual sound source 104 to the position of the speaker 106-l and the inward normal vector n(r _l ) of the boundary surface at the position of the speaker 106-l. Calculate the angle _θl .

The angle weight adding section 13-l sets the angle weight w _C (θ _l ) in the above equation (9) based on the formed angle θ _l . Then, the angle weight adding unit 13-l multiplies the signal to which the area element is added by the angle weight w _C (θ _l ), thereby generating a signal reflecting the formed angle θ _l as the drive signal d(r _l ). is output to the speaker 106-l.

As a result, since the term e ^-jk||rl-rs|| representing the time delay in the above equation (8) is ignored, the system can be simplified. Also, the system can be simplified by using the HPF 10-l of HPFh(r _l ,r _s ) that approximates the term jk||r _l −r _s ||+1.

Therefore, by simplifying the configuration of the WFS by approximation, it is possible to generate the drive signal d(r _l ) that expresses the distance of the virtual sound source 104 based on the WFS without increasing the scale of the system.

(Other examples of HPF10-l)
The HPF 10- _l (10-1 to 10- _L ) of the object-based acoustic rendering device 1 shown in FIG. Using HPFh(r _l , r _s ), the signal amplified by the signal amplifier 9-l (9-1 to 9-L) is filtered.

For example, the term jk||r ₁ −r _s ||+1 in the above equation (8) is replaced with a high-pass filter expressed by the following equation.

αは、フィルタの特性を決定するためのパラメータであり、正の実数である。Ｎはフィルタ次数である。これらのパラメータα及びフィルタ次数Ｎの値は、ユーザが任意に決定するものとする。 x[t] and y[t] are the input and output of the HPF 10-l at time t. The HPF coefficient h _n (r _l , r _s ) shall be represented by the following equation. n=0, 1, .

α is a parameter for determining filter characteristics and is a positive real number. N is the filter order. The values of these parameter α and filter order N are arbitrarily determined by the user.

That is, the HPF 10-l inputs the virtual sound source coordinates r _S and the speaker coordinates r _l as well as the parameter α and the filter order N preset by the user. Then, the HPF 10-l sets HPF coefficients having equation (12) as coefficients based on the virtual sound source coordinates r _s , the speaker coordinates r _l , the parameter α and the filter order N.

Then, the HPF 10-l receives the signal amplified by the signal amplifier 9-l (9-1 to 9-L), and calculates the HPF coefficient h _n (r l , r _l , r _s ), filter processing is performed so that the input/output characteristics of the HPF 10-1 are as shown in the above equation (11). In other words, the HPF 10-l is composed of an HPF that has the input/output characteristics of the above equation (11).

As a result, the object-based acoustic rendering device 1 as a whole can be simplified without increasing the scale of the system.

(Another example of attenuation adding section 11-l)
Further, the attenuation addition unit 11- _l (11-1 to 11- _L ) of the object-based acoustic rendering apparatus 1 shown in FIG. 1 calculates the attenuation coefficient 1/| By setting |r _l −r _S || ² and multiplying the filtered signal by an attenuation factor of ¹ /||r _l −r _S || A signal attenuated according to the distance between l.

However, the attenuation coefficient ¹ / _|| r _l - r _{S ||} I can't. Therefore, the attenuation adding unit 11-l uses an attenuation coefficient g(r _l , r _s ) represented by the following equation that approximates the attenuation coefficient 1/||r _l −r _s || ² .

β ₁ is a positive real number for adjusting the signal amplitude, and β ₂ is a positive real number for suppressing the divergence of the damping coefficients g(r _l , r _s ). The values of these parameters β ₁ and β ₂ are arbitrarily determined by the user. In particular, the value of the parameter β ₂ is set by the user to a very small value so as to suppress the divergence of the attenuation coefficients g(r _l , r _s ).

That is, the attenuation adding unit 11-l obtains the absolute value ||r _l −r _S || of the vector from the position of the virtual sound source 104 to the position of the speaker 106-l, and squares the absolute value to obtain the parameter β ₂ is added to obtain the addition result (||r _l −r _S || ² +β ₂ ), and the parameter β ₁ is divided by the addition result (||r _l −r _S || ² +β ₂ ) to obtain the attenuation Determine the coefficient g(r _l ,r _s ).

Then, the attenuation addition unit 11-l multiplies the filtered signal by g(r _l ,r _s ), so that according to the distance between the virtual sound source 104 and the speaker 106-l Generates an attenuated signal.

The smaller the value of the parameter β ₂ , the closer the behavior of the damping coefficient g(r ₁ , r _s ) to the damping coefficient 1/||r ₁ −r _s || ² . On the other hand, as the virtual sound source coordinate r _S approaches the speaker coordinate r ₁ , the signal amplitude increases extremely.

As a result, the divergence of the signal can be suppressed, and the user can adjust the fluctuation of the signal amplitude when the position of the acoustic object changes according to the values of the parameters β ₁ and β ₂ set by the user. can.

Further, when the user sets the values of the parameters β ₁ and β ₂ to β ₁ =β ₂ , when the virtual sound source coordinates r _S and the speaker coordinates r _l match (r _S =r _l ), the attenuation coefficient g (r _l , r _S )=1.

Therefore, the user can use the values of these parameters β ₁ and β ₂ as a reference for adjustment so as not to increase or attenuate the signal unnecessarily.

Further, when the user sets the values of the parameters β ₁ and β ₂ to β ₁ =β ₂ /ΔS ₁ , when the virtual sound source coordinates r _s and the speaker coordinates r ₁ match (r _s =r ₁ ), The damping coefficient g(r _l , r _s )ΔS _l =1, and h(r _l ,r _s )g(r _l ,r _s )ΔS _{l wc} (θ _l )=1. This is because h(r _l ,r _s )=1 and w _C (θ _l )=1.

Therefore, when the virtual sound source coordinates r _S and the speaker coordinates r _l match, the driving signal d(r _l ) output from the angle weighting unit 13-l to the speaker 106-l is equal to the signal amplification unit 9-l. is the same as the signal amplified by In other words, a signal amplified with respect to the sound source signal S input by the object-based acoustic rendering apparatus 1 is reproduced from the speaker 106- _l located at the speaker coordinate r 1 .

In this way, when the virtual sound source coordinate r _S and the speaker coordinate r _l match by the attenuation adding unit 11-l using the attenuation coefficient g(r _l , r _S ) represented by the above equation (13) However, the signal never diverges infinitely. Therefore, it is possible to solve the problem that the signal cannot be reproduced.

[Example 2]
Next, the object-based acoustic rendering device of Example 2 will be described. As described above, in the second embodiment, by incorporating the VBAP configuration into the configuration of the first embodiment, in addition to the effects of the first embodiment, the drive signal d (r _l ) to solve the problem of becoming smaller. More specifically, according to the second embodiment, the configuration of a part of the simplified WFS shown in the first embodiment and the configuration of the VBAP are seamlessly switched in accordance with the angle weight, so that the drive signal d(r _l ) to generate

In general, when using the WFS sound field reproduction method, it is assumed that a large number of speakers 106-l are densely arranged. However, in home audio, it is difficult to arrange many speakers 106-l densely, and the speakers 106-l are normally arranged sparsely.

FIG. 4 is a diagram for explaining a case where the speakers 106-l are sparsely arranged. As shown in FIG. 4, when the speakers 106-l are sparsely arranged in the reproduced sound field and the position of the virtual sound source 104 (virtual sound source coordinates r _S ) is close to the boundary surface of the area where the sound field is desired to be reproduced, assume.

In this case, for all speakers 106-l (106-1 to 106-L), the vector (r _l −r _S ) connecting the position of the virtual sound source 104 and the position of the speaker 106-l and the boundary at the position of the speaker 106-l The angle θ _l formed with the in-plane normal vector n(r _l ) becomes a value close to 90° or a value exceeding 90°.

Therefore, the angle weight w _C (θ _l ) used in the angle weight adding section 13-l is a value close to 0 or 0 from the above equation (9). Then, the value of the drive signal d(r _l ) for all the speakers 106-1 becomes a small value or 0, and the reproduced signal becomes small even though the virtual sound source 104 is close to the boundary surface. A problem arises.

In order to solve this problem, in the second embodiment, in the object-based acoustic rendering apparatus ₁ of the first embodiment shown in FIG. Add VBAP configuration to seamlessly switch to the distributive law.

Here, in the object-based acoustic rendering apparatus 1 of the first embodiment, which is the simplified WFS shown in FIG. 1, HPFh(r _l , r _s ) of HPF 10-l is a term related to frequency correction. Also, the attenuation coefficient ¹ /||r _l −r _{S ||} It is interpreted as a term related to correction by discretizing speaker 106-l. Further, the angle weight w _C (θ _l ) of the angle weight adding section 13-l is interpreted as a term relating to the signal distribution side for each speaker 106-l.

In the second embodiment, the term regarding the signal distribution rule for each speaker 106-l based on the angle weight w _C (θ _l ) of the angle weight adding unit 13-l in WFS includes the signal for each speaker 106-l determined by VBAP. Concatenate the distributive law terms of .

FIG. 5 is a block diagram showing a configuration example of the object-based acoustic rendering device of the second embodiment, and FIG. 6 is pseudocode showing a processing example of the object-based acoustic rendering device of the second embodiment.

This object-based acoustic rendering device 2 includes signal amplification units 9-1 to 9-L, HPFs 10-1 to 10-L, attenuation addition units 11-1 to 11-L, and area element addition units 12-1 to 12-L. , angle weight addition units 13-1 to 13-L, VBAP coefficient multiplication units 14-1 to 14-L, angle weight addition units 15-1 to 15-L, addition units 16-1 to 16-L, angle calculation units 20 and a VBAP coefficient calculator 21 .

Hereinafter, in the object-based acoustic rendering device 2, the configuration units corresponding to the l-th speaker 106-l (l-th system) are the signal amplification unit 9-l, the HPF 10-l, the attenuation addition unit 11- 1, an area element adder 12-l, an angle weight adder 13-l, a VBAP coefficient multiplier 14-l, an angle weight adder 15-l, and an adder 16-l. That is, the object-based acoustic rendering device 2 includes L signal amplifiers 9-l, HPFs 10-l, attenuation adders 11-l, area element adders 12-l, angle weight adders 13-l, VBAP coefficients A multiplication unit 14-l, an angle weight addition unit 15-l and an addition unit 16-l are provided, and an angle calculation unit 20 and a VBAP coefficient calculation unit 21 are provided.

The signal amplifier 9-l, HPF 10-l, attenuation adder 11-l, area element adder 12-l, and angle weight adder 13-l are components of the WFS. The VBAP coefficient multiplier 14-l and the angle weighting unit 15-l are components of the VBAP, and are connected in parallel to the WFS angle weighting unit 13-l.

Comparing the object-based acoustic rendering device 1 of the first embodiment and the object-based acoustic rendering device 2 of the second embodiment shown in FIG. They are common in that they include an HPF 10-l, an attenuation addition section 11-l, an area element addition section 12-l, an angle weight addition section 13-l, and an angle calculation section 20. FIG.

On the other hand, the object-based acoustic rendering device 2 includes a VBAP coefficient multiplier 14-l, an angle weight adder 15-l, an adder 16-l, and a VBAP coefficient calculator 21. It differs from the object-based acoustic rendering device 1 which does not have it.

The overall processing of the object-based acoustic rendering device 2 will be described with reference to FIG. The object-based acoustic rendering device 2 inputs the sound source signal S and the virtual sound source coordinates r _S of the virtual sound source 104 (step S601), as in step S201 of FIG.

Similar to step S202 in FIG. 2, the object-based acoustic rendering device 2 inputs the speaker coordinates r _l , the area element ΔS _l and the boundary surface inward normal vector n(r _l ) for the speaker 106-l (step S602).

Similar to step S203 in FIG. 2, the object-based acoustic rendering device 2 sets HPFh (r _l , r _s ) for the speaker 106-l based on the virtual sound source coordinate r _S and the speaker coordinate r _l (step S603). ).

Similar to step S204 in FIG. 2, the object-based acoustic rendering device ² calculates the attenuation coefficient _{1/||r l −r S ||} is set (step S604).

_Similar to step _S205 in FIG. 2, the object-based acoustic rendering device 2 _creates a The angle _θl is calculated (step S605).

The object-based acoustic rendering device 2 determines whether or not the absolute value |θ _l | of the angle θ _l formed by the speaker 106-l is larger than 0° and smaller than 90°. , and the _{VBAP angle weight w S (} θ _l ) is set by the _following equation (14) (step S606).

Specifically, when the object-based acoustic rendering device 2 determines that the formed angle |θ _l | is larger than 0° and smaller than 90° (cos θ _l >0 ), set the angle weight w _C (θ _l )=cos θ _l and the angle weight w _S (θ _l )=|1−cos θ _l |. On the other hand, when the object-based acoustic _rendering device 2 determines that the formed angle |θ _l | case), set the angle weight w _C (θ _l )=0 and the angle weight w _S (θ _l )=0. This angle weight w _C (θ _l ) is used by the angle weight adding section 13-l, and the angle weight w _S (θ _l ) is used by the angle weight adding section 15-l.

The angle weight w _C (θ _l ) takes a value in the range from 0 to 1. When the angle |θ _l | is 0°<|θ _l |<90°, the angle |θ _l | The closer the angle is to °, the closer the value is to ₁ ( _cos θ _l ), and the closer to 90° is, the closer the value is to 0 _. Takes a value of 0 in the range.

The angle weight w _S (θ _l ) takes a value closer to 0 as the angle |θ _l | _approaches 0° in the range of 0°<|θ _l |<90°, The closer the angle is to 90°, the closer the value is to 1 (|1-cos θ _l |), and the angle |θ _l | is 0 in the range of |θ _l |≦0° or 90°≦|θ _l |. Take.

The object-based acoustic rendering device 2 generates a unit vector of the virtual sound source direction from a predetermined sound receiving point (listener's position) to the virtual sound source coordinate r _S and all the speakers 106-l from the predetermined sound receiving point to the speaker coordinate r Based on the speaker direction unit vector to _l , the three speakers containing the virtual sound source 104 are identified as the three VBAP target speakers 106-n1, 106-n2, and 106-n3.

Then, the object-based acoustic rendering device 2 acquires speaker direction unit vectors r _n1 , r _n2 , and r _n3 for the three VBAP target speakers 106-n1, 106-n2, and 106-n3 (step S607). The unit vectors r _n1 , r _n2 and r _n3 can be obtained based on the predetermined sound receiving point and the coordinates (speaker coordinates) of the speakers 106-n1, 106-n2 and 106-n3. n1, n2, n3 are the indices of the three speakers 106-n1, 106-n2, 106-n3 for VBAP.

前記式（１５）のｒ_nSは、仮想音源座標ｒ_Sへの仮想音源方向の単位ベクトルである。 Based on the unit vector of the virtual sound source direction to the virtual sound source coordinate r _S and the unit vectors of the speaker directions r _n1 , r _n2 , r _n3 , the object-based acoustic rendering device 2 uses the following equations to generate the speaker 106-n1, 106 −n2, 106−Calculate coefficients g _l =g _n1 , g _n2 , g _n3 corresponding to n3 (step S608).

r _nS in the above equation (15) is the unit vector of the virtual sound source direction to the virtual sound source coordinate r _S .

Also, the object-based acoustic rendering device 2 sets the coefficient g _l =0 for the speaker 106-l other than the speakers 106-n1, 106-n2, and 106-n3 among the speakers 106-1 to 106-L. These coefficients g _l =g _n1 , g _n2 , g _n3 , 0 are calculated and set by the VBAP coefficient calculator 21 .

The object-based acoustic rendering device 2 uses a constant u (for example, u=1/2π) for the speakers 106-n1, 106-n2, and 106-n3 with indices l=n1, n2, and n3, and the sound source input in step S601. Signal S and virtual sound source coordinates r _S , speaker coordinates r _l and area element ΔS _l input in step S602, HPFh (r _l , r _S ) set in step S603, attenuation coefficient 1/ ||r _l −r _S || ² and based on the angle weight w _C (θ _l ) and angle weight w _S (θ _l ) set in step S606, drive signal d (r _l ) is calculated by the following equation: Calculate and output (step S609).

In this equation, the coefficients g _l =g _n1 , g _n2 , g _n3 . Also, * represents convolution. The drive signal d(r _l ) is applied to the signal amplifier 9-l, the HPF 10-l, the attenuation adder 11-l, the area element adder 12-l, the angle weight adder 13-l, and the VBAP coefficient multiplier 14-l. , is calculated by the angle weighting unit 15-l and the addition unit 16-l.

この式（１７）は、前記式（１０）と同じである。 On the other hand, the object-based acoustic rendering device 2 calculates constant u, sound source signal S, Based on virtual sound source coordinates r _S , speaker coordinates r _l and area element ΔS _l , HPFh(r _l ,r _S ), damping coefficient 1/||r _l −r _S || ² and angle weight w _C (θ _l ) , the drive signal d(r _l ) is calculated and output by the following equation (step S610).

This formula (17) is the same as the above formula (10).

This drive signal d(r _l ) is calculated by the signal amplifier 9-l, HPF 10-l, attenuation adder 11-l, area element adder 12-l, and angle weight adder 13-l.

Next, the processing of the components of the object-based acoustic rendering device 2 will be described with reference to FIG. Signal amplification unit 9-l (9-1 to 9-L), HPF 10-l (10-1 to 10-L), attenuation addition unit 11-l (11-1 to 11-L), area element addition unit 12 -l (12-1 to 12-L), angle weighting unit 13-l (13-1 to 13-L), and angle calculation unit 20 are the same as the components shown in FIG. omitted.

Here, the angle weighting unit 13- _l outputs the WFS drive signal reflecting the formed angle θl as the first drive signal to the corresponding addition unit 16-l. The angle calculator 20 outputs the formed angle θ _l to the corresponding angle weight adder 13-l and angle weight adder 15-l.

The VBAP coefficient calculator 21 inputs the virtual sound source coordinate r _S and the speaker coordinates r ₁ to r _L . Then, as in steps S607 and S608, the VBAP coefficient calculation unit 21 calculates the unit vector of the virtual sound source direction from the predetermined sound receiving point to the virtual sound source coordinate r _S and the predetermined reception at all the speakers 106-1 to 106-L. Coefficient g corresponding to the three speakers 106-n1, 106-n2, 106-n3 of the VBAP target including the virtual sound source 104 inside, based on the unit vector of the speaker direction from the sound point to the speaker coordinates r ₁ to r _L Calculate _n1 , _gn2 and _gn3 .

The VBAP coefficient calculator 21 multiplies the coefficients g _l =g _n1 , g _n2 , g _n3 by the VBAP coefficient multipliers 14-n1, 14-n2, 14-n3 corresponding to the speakers 106-n1, 106-n2, 106-n3. output to n3 respectively. The VBAP coefficient calculator 21 also outputs the coefficient g _l =0 to the VBAP coefficient multipliers 14-l corresponding to the speakers 106-l other than the speakers 106-n1, 106-n2, and 106-n3.

FIG. 7 is a block diagram showing a configuration example of the VBAP coefficient calculator 21. As shown in FIG. The VBAP coefficient calculator 21 includes a speaker determiner 31 and a calculator 32 . The speaker determination unit 31 inputs the virtual sound source coordinates r _S and the speaker coordinates r ₁ to r _L of all the speakers 106-1 to 106-L. Then, the speaker determining unit 31 selects three VBAP target speakers 106-n1, 106-n2, and 106-n3 containing the virtual sound source 104 based on the virtual sound source coordinate r _S and the speaker coordinates r ₁ to r _L . Identify.

The speaker determination unit 31 acquires the speaker direction unit vectors r _n1 , r _n2 , and r _n3 of the three VBAP target speakers 106-n1, 106-n2, and 106-n3, and determines the virtual sound source coordinate r _S and the speaker direction. The unit vectors r _n1 , r _n2 and r _n3 are output to the calculator 32 .

The calculation unit 32 receives the virtual sound source coordinates r _S and the speaker direction unit vectors r _n1 , r _n2 , and r _n3 from the speaker determination unit 31 . Then, the calculation unit 32 _calculates the _{speaker 106} - _n1 , Calculate coefficients g _n1 , g _n2 and g _n3 corresponding to 106-n2 and 106-n3. The calculator 32 then outputs the coefficients g _n1 , g _n2 and g _n3 to the corresponding VBAP coefficient multipliers 14-n1, 14-n2 and 14-n3.

Calculation unit 32 also sets coefficient g _l =0 corresponding to speaker 106-l other than speakers 106-n1, 106-n2, and 106-n3, and outputs it to corresponding VBAP coefficient multiplication unit 14-l.

Returning to FIG. 5, the VBAP coefficient multiplier 14-l (14-1 to 14-L) receives the coefficient g _l (one of g _n1 , g _n2 , g _n3 , 0) from the VBAP coefficient calculator 21. value). Then, the VBAP coefficient multiplier 14-l receives the signal to which the area element is added from the area element adding unit 12-l and multiplies the signal by the coefficient g _l to obtain a signal reflecting the coefficient g _l . to generate

The VBAP coefficient multiplier 14-l outputs a signal reflecting the coefficient g _l to the angle weight adder 15-l.

The angle weight addition unit 15-l (15-1 to 15-L) inputs the angle θ _l (θ ₁ to θ _L ) formed from the angle calculation unit 20, and based on the formed angle θ _l , as in step S606 , the angle weight w _S (θ _l ) is set by the above equation (14). Then, the angle weight addition unit 15-l receives the signal reflecting the coefficient g _l from the VBAP coefficient multiplication unit 14-l, and multiplies the signal by the angle weight w _S (θ _l ) to form an angle Generate a signal reflecting _θl .

The signal reflecting the angle _θl formed by the angle weighting units 15-n1, 15-n2, and 15-n3 corresponding to the three speakers 106-n1, 106-n2, and 106-n3 including the virtual sound source 104 is , the closer the angle θ _l to 90°, the closer to the signal reflecting the coefficient g _l . On the other hand, the sound source signal S reflecting the formed angle _θl becomes a signal closer to 0 as the formed angle _θl approaches 0°. In addition, in the angle weight addition unit 15-l corresponding to the speaker 106-l other than the three speakers 106-n1, 106-n2, and 106-n3 including the virtual sound source 104 inside, the signal reflecting the angle θ _l formed is is 0.

The angle weight addition section 15-l outputs a signal reflecting the formed angle θ _l to the addition section 16-l as a second drive signal.

The adders 16-l (16-1 to 16-L) receive the first drive signal reflecting the angle θ _l formed by the angle weight addition unit 13-l, and the angle θ l formed by the angle weight addition unit 15-l. A second drive signal reflecting _θl is input. Then, the adder 16-l adds the first drive signal reflecting the formed angle θ _l and the second drive signal reflecting the formed angle θ _l , and the addition result is used as the drive signal d(r _l ) for the speaker 106-l. output to l.

As described above, according to the object-based acoustic rendering apparatus 2 of the second embodiment, the configuration of the VBAP is incorporated into the configuration of the WFS of the first embodiment, and the configuration of a part of the WFS and the configuration of the VBAP are combined with the angle weights. The drive signal d(r _l ) is generated by seamlessly switching according to

Specifically, the VBAP coefficient calculation unit 21, based on the unit vector of the virtual sound source direction from a predetermined sound receiving point to the virtual sound source coordinate r _S and the unit vector of the speaker direction to the speaker coordinates r ₁ to r _L , Coefficients g _n1 , g _n2 , g _n3 corresponding to the three speakers 106-n1, 106-n2, 106-n3 containing the virtual sound source 104 are calculated.

The VBAP coefficient multiplier 14-l receives the coefficient g _l (one of g _n1 , g _n2 , g _n3 and 0) from the VBAP coefficient calculator 21 . Then, the VBAP coefficient multiplier 14-l multiplies the signal obtained by the signal amplifier 9-l, HPF 10-l, attenuation adder 11-l, and area element adder 12-l by the coefficient g _l . , to produce a signal reflecting the coefficient g _l .

The angle weight adding unit 15-l sets the angle weight w _S (θ _l ) in the above equation (14) based on the formed angle θ _l . Then, the angle weight adding section 15-l multiplies the signal reflecting the coefficient g _l by the angle weight w _S (θ _l ) to generate a second drive signal reflecting the formed angle θ _l .

The adder 16-l is composed of the signal amplifier 9-l, the HPF 10-l, the attenuation adder 11-l, the area element adder 12-l, and the angle weight adder 13-l. The first drive signal reflecting the formed angle θ _l and the second drive signal reflecting the formed angle θ _l are added, and the addition result is output to the speaker 106-l as the drive signal d(r _l ).

Thus, the angle weighting unit 15-l using the angle weight w _S (θ _l ) is connected in series to the VBAP coefficient multiplier 14-l using the coefficient g _l , and the VBAP coefficient multiplier 14 of VBAP -l and the angle weighting unit 15-l are connected in parallel to the WFS angle weighting unit 13-l. The angle weight w _C (θ _l ) used in the angle weight addition unit 13-l and the angle weight w _S (θ _l ) used in the angle weight addition unit 15-l have a trade-off relationship in the range of 0 to 1. It is in.

Therefore, when the position of the virtual sound source 104 (virtual sound source coordinates r _S ) is away from the boundary surface of the speaker 106-l and the formed angle θ _l approaches 0°, the angle weight w _C (θ _l ) takes a large value close to 1, but the angle weight w _S (θ _l ) takes a small value close to 0. In this case, the drive signal d(r _l ) is dominant on the distribution side by WFS.

On the other hand, when the position of the virtual sound source 104 (virtual sound source coordinates r _S ) is close to the boundary surface of the speaker 106-l and the formed angle θ _l approaches 90°, the angle weight w _C (θ _l ) is Although it becomes a small value close to 0, the angle weight w _S (θ _l ) becomes a large value close to 1. In this case, the drive signal d(r _l ) is dominant on the distribution side by VBAP.

That is, the distribution side by WFS and the distribution side by VBAP are continuously and seamlessly switched according to the position of the virtual sound source 104 with respect to the speaker 106-l.

Therefore, the object-based acoustic rendering device 2 of the second embodiment can achieve the same effects as those of the first embodiment. Further, in an environment where the speakers 106- _l are sparsely arranged, the _WFS angle The weight is small, the VBAP angle weight is large, and the rendering rule switches continuously. Therefore, even if the reproduced signal becomes small due to the decrease in the angle weight of the WFS, the problem that the reproduced signal becomes extremely small can be solved by compensating for it with the angle weight of the VBAP.

Note that the _HPF 10-1 (10-1 to 10- _L ) of the object-based acoustic rendering device 2 of the second embodiment is similar to the first embodiment shown in FIG. may be replaced with the high-pass filter of the above equation (11) using the HPF coefficient h _n (r _l , r _s ) of the above equation (12).

Further, the attenuation adding unit 11-l (11-1 to 11-L) of the object-based acoustic rendering apparatus 2 of the second embodiment has an attenuation coefficient of 1/||r _{l Instead} of ^-r _{S ||} That is, attenuation adding section 11-l uses attenuation coefficient g(r _l , r _s ) to generate a signal that is attenuated according to the distance between virtual sound source 104 and speaker 106-l.

[Example 3]
Next, Example 3 will be described. As described above, in Example 3, similar to Example 2, by incorporating the VBAP configuration into the configuration of Example 1, in addition to the effect of Example 1, the speakers 106-l are sparsely arranged. To solve the problem that the drive signal d(r _l ) becomes small when More specifically, in the third embodiment, the driving signal d(r _l ) is changed to Generate.

FIG. 8 is a block diagram showing a configuration example of the object-based acoustic rendering device of Example 3, and FIG. 9 is pseudo code showing a processing example of the object-based acoustic rendering device of Example 3. In FIG.

This object-based acoustic rendering device 3 includes signal amplification units 9-1 to 9-L, HPFs 10-1 to 10-L, attenuation addition units 11-1 to 11-L, and area element addition units 12-1 to 12-L. , angle weight addition units 13-1 to 13-L, VBAP coefficient multiplication units 14-1 to 14-L, angle weight addition units 15-1 to 15-L, addition units 16-1 to 16-L, angle calculation units 20 and a VBAP coefficient calculator 21 .

The signal amplification unit 9-l, the HPF 10-l, the attenuation addition unit 11-l, the area element addition unit 12-l, and the angle weight addition unit 13-l are components of the WFS, and the VBAP coefficient multiplication unit 14-l and The angle weighting unit 15-l is a component of VBAP. The WFS component and the VBAP component are connected in parallel as the object-based acoustic rendering device 3 as a whole.

Comparing the object-based acoustic rendering device 2 of the second embodiment and the object-based acoustic rendering device 3 of the third embodiment shown in FIG. have in common.

On the other hand, in the object-based acoustic rendering device 3, the VBAP coefficient multiplier 14-l and the angle weighting unit 15-l, which are the components of the VBAP, are connected in parallel with the overall components of the WFS. is connected in parallel with only a part of the angle weighting unit 13-l.

The overall processing of the object-based acoustic rendering device 3 will be described with reference to FIG. Since the processing of steps S901 to S908 shown in FIG. 9 is the same as the processing of steps S601 to S608 by the object-based acoustic rendering apparatus 2 of the second embodiment shown in FIG. 6, description thereof is omitted here.

When the index of the speaker coordinates r _l acquired in step S907 is l=n1, n2, n3, the object-based acoustic rendering device 3 sets a constant u (for example, u = 1/2 π), the sound source signal _S and the virtual sound source coordinates r s input in step S901, the speaker coordinates r _l and the area element ΔS _l input in step S902, and the HPFh (r _l , r _S ), based on the attenuation coefficient 1/||r _l −r _S || ² set in step S904 and the angle weight w _C (θ _l ) and angle weight w _S (θ _l ) set in step S906, A drive signal d(r _l ) is calculated and output by the following equation (step S909).

In this equation, the coefficients g _l =g _n1 , g _n2 , g _n3 . Also, * represents convolution. The drive signal d(r _l ) is applied to the signal amplifier 9-l, the HPF 10-l, the attenuation adder 11-l, the area element adder 12-l, the angle weight adder 13-l, and the VBAP coefficient multiplier 14-l. , is calculated by the angle weighting unit 15-l and the addition unit 16-l.

この式（１９）は、前記式（１０）及び前記式（１７）と同じである。 On the other hand, when the index is other than l=n1, n2, n3, the object-based acoustic rendering device 3, for the speaker 106-l other than the speakers 106-n1, 106-n2, 106-n3, Based on virtual sound source coordinates r _S , speaker coordinates r _l and area element ΔS _l , HPFh(r _l ,r _S ), damping coefficient 1/||r _l −r _S || ² and angle weight w _C (θ _l ) , the driving signal d(r _l ) is calculated and output by the following equation (step S910).

This formula (19) is the same as the formula (10) and the formula (17).

This drive signal d(r _l ) is calculated by the signal amplifier 9-l, HPF 10-l, attenuation adder 11-l, area element adder 12-l, and angle weight adder 13-l.

In the calculation of the above equation (18), a delay occurs due to filtering between the calculation result of the WFS configuration, which is the first term on the right side, and the calculation result of the VBAP configuration, which is the second term. Therefore, it is necessary to add a delay for adjusting the phase on the VBAP side in the angle weighting units 13-l and 15-l, but the notation thereof is omitted here.

Further, in the formulas (18) and (19), the convolution * may be obtained by inversely transforming the product in the frequency domain using FFT (Fast Fourier Transform). The same applies to the formulas (16) and (17).

Referring to FIG. 8, the processing of each component included in the object-based acoustic rendering device 3 is the same as the processing of each component included in the object-based acoustic rendering device 2 of the second embodiment shown in FIG. Therefore, the description of the processing of the configuration unit is omitted.

The input data of the VBAP coefficient multipliers 14-l (14-1 to 14-L) differ between the object-based acoustic rendering devices 2 and 3. FIG. The VBAP coefficient multiplier 14-l of the object-based acoustic rendering apparatus 2 shown in FIG. 5 receives the signal added with the area element from the area element adding unit 12-l. On the other hand, the VBAP coefficient multiplier 14-l of the object-based acoustic rendering device 3 shown in FIG. 8 receives the sound source signal S as input.

Specifically, the _{VBAP coefficient} multiplier 14- _l of the object-based acoustic rendering device ₃ shown in FIG. value). Then, the VBAP coefficient multiplier 14-l receives the sound source signal S and multiplies the sound source signal S by the coefficient g _l to generate a signal reflecting the coefficient g _l .

As described above, according to the object-based acoustic rendering apparatus 3 of the third embodiment, the configuration of the VBAP is incorporated into the configuration of the WFS of the first embodiment, and the overall configuration of the WFS and the configuration of the VBAP are combined into angle weights. The driving signal d(r _l ) is generated by switching seamlessly according to the demand.

Specifically, the VBAP coefficient multiplier 14-l receives the coefficient g _l (one of g _n1 , g _n2 , g _n3 , and 0) from the VBAP coefficient calculator 21 . Then, the VBAP coefficient multiplier 14-l multiplies the sound source signal S by the coefficient g _l to generate a signal reflecting the coefficient g _l .

The angle weight adding unit 15-l sets the angle weight w _S (θ _l ) in the above equation (14) based on the formed angle θ _l . Then, the angle weight adding section 15-l multiplies the signal reflecting the coefficient g _l by the angle weight w _S (θ _l ) to generate a second drive signal reflecting the formed angle θ _l .

The adder 16-l is composed of the signal amplifier 9-l, the HPF 10-l, the attenuation adder 11-l, the area element adder 12-l, and the angle weight adder 13-l. The first drive signal reflecting the formed angle θ _l and the second drive signal reflecting the formed angle θ _l are added, and the addition result is output to the speaker 106-l as the drive signal d(r _l ).

Thus, the angle weight adding section 15-l using the angle weight w _S (θ _l ) is connected in series to the VBAP coefficient multiplying section -l using the coefficient g _l . In addition, the VBAP coefficient multiplier 14-l and the angle weight addition unit 15-l of the VBAP are the signal amplification unit 9-l of the WFS, the HPF 10-l, the attenuation addition unit 11-l, the area element addition unit 12-l, and the angle It is connected in parallel to the weight adding section 13-l. The angle weight w _C (θ _l ) used in the angle weight addition unit 13-l and the angle weight w _S (θ _l ) used in the angle weight addition unit 15-l have a trade-off relationship in the range of 0 to 1. It is in.

Therefore, as in the second embodiment, when θ _l approaches 0°, the drive signal d(r _l ) is dominated by the WFS distribution side, and when θ _l approaches 90°, the drive signal d (r _l ) is dominated by the VBAP distribution side.

In other words, the distribution side of WFS and VBAP is continuously switched seamlessly according to the position of the virtual sound source 104 with respect to the speaker 106-l.

Therefore, the object-based acoustic rendering device 3 of the third embodiment can achieve the same effects as those of the first embodiment. Also, as in the second embodiment, in an environment where the speakers 106-l are sparsely arranged, when the virtual sound source 104 is placed close to the boundary surface during rendering by WFS, rendering by VBAP continuously and seamlessly. Therefore, it is possible to solve the problem that the reproduced signal becomes small.

Note that the HPF 10-1 (10-1 to 10-L) of the object-based acoustic rendering device 3 of the third embodiment is similar to the first embodiment shown in FIG. 1 and the second embodiment shown in FIG. |r _l −r _s ||+1 may be replaced with the high-pass filter of the above equation (11) using the HPF coefficient h _n (r _l , r _s ) of the above equation (12).

Further, the attenuation adding unit 11-l (11-1 to 11-L) of the object-based acoustic rendering device 3 of the third embodiment is similar to the first embodiment shown in FIG. 1 and the second embodiment shown in FIG. , the damping coefficient g(r _l , r _s ) of the above equation (13) may be used instead of the damping coefficient 1/||r ₁ −r _s || ² . That is, attenuation adding section 11-l uses attenuation coefficient g(r _l , r _s ) to generate a signal that is attenuated according to the distance between virtual sound source 104 and speaker 106-l.

However, when the virtual sound source 104 is placed close to the speaker 106-l, the simplified WFS configuration (HPF 10-l to angle weighting unit 13-l) and the VBAP configuration (VBAP coefficient multiplier 14- 1 and the angle weighting unit 15-l) may have significantly different signal amplitudes. Therefore, the parameters β1 and β2 used to calculate the attenuation coefficient g(r _l , r _s ) of the above equation (13) need to be adjusted appropriately so that the signal amplitudes do not differ significantly.

Although the present invention has been described above with reference to Examples 1, 2, and 3, the present invention is not limited to Examples 1, 2, and 3, and can be variously modified without departing from the technical idea thereof. be.

A normal computer can be used as the hardware configuration of the object-based acoustic rendering apparatuses 1, 2, and 3 according to the first, second, and third embodiments of the present invention. The object-based acoustic rendering apparatuses 1, 2, and 3 are configured by a computer having a CPU, a volatile storage medium such as RAM, a non-volatile storage medium such as ROM, and an interface.

HPFs 10-1 to 10-L, attenuation addition units 11-1 to 11-L, area element addition units 12-1 to 12-L, and angle weight addition units 13-1 to 13- provided in the object-based acoustic rendering device 1 Each function of L and the angle calculation unit 20 is realized by causing the CPU to execute a program describing these functions.

Also, HPFs 10-1 to 10-L, attenuation addition units 11-1 to 11-L, area element addition units 12-1 to 12-L, angle weight addition unit 13- 1 to 13-L, VBAP coefficient multipliers 14-1 to 14-L, angle weight adders 15-1 to 15-L, adders 16-1 to 16-L, angle calculator 20 and VBAP coefficient calculator 21 Each function of is realized by causing the CPU to execute a program describing these functions.

These programs are stored in the storage medium and are read and executed by the CPU. In addition, these programs can be stored and distributed in storage media such as magnetic disks (floppy (registered trademark) disks, hard disks, etc.), optical disks (CD-ROM, DVD, etc.), semiconductor memories, etc., and distributed via networks. You can also send and receive

1, 2, 3 Object-based acoustic rendering device 9 Signal amplifier 10 HPF (high pass filter)
11 attenuation addition unit 12 area element addition units 13, 15 angle weight addition unit 14 VBAP coefficient multiplication unit 16 addition unit 20 angle calculation unit 21 VBAP coefficient calculation units 30, 32 calculation unit 31 speaker determination unit 100 sound receiving points 101, 104 virtual Sound sources 102, 106 Speaker 103 Sound source 105 Speaker array r _nS unit vector in virtual sound source direction r _n1 , r _n2 , r _n3 unit vector in speaker direction g _l , g _n1 , g _n2 , g _n3 coefficient r _S virtual sound source coordinate r _l Speaker coordinates C1, C2 Region S Sound source signal L Number of speakers l Speaker number (system number)
ΔS _l speaker area element _n ( _{r l} ) speaker boundary surface inward normal vector _k wave number angle with in-plane normal vector n(r _l ))
h(r _l , r _s ) HPF
w _C (θ _l ), w _S (θ _l ) Angle weight 1/||r _l −r _S || ² , g (r _l , r _S ) Attenuation coefficient d (r _l ) Drive signal

Claims (6)

An object-based acoustic rendering device that generates drive signals for each of a plurality of speakers placed in a listening environment by rendering a sound source object placed at a position described in acoustic metadata,
L is the number of the plurality of speakers, l (=1, . The sound source coordinates are r _s , the coordinates of the first speaker are the speaker coordinates r _l , the boundary surface inward normal vector at the position of the first speaker is n(r _l ), and the position of the first speaker is the center. _Let ΔS _l be the area element for
For each of the plurality of speakers, a vector from the position of the virtual sound source coordinate r _S to the position of the speaker coordinate r _l of the l-th speaker and the inward normal vector n ( r _l ), and an angle calculator for calculating the angle θ _l formed with
A signal amplification unit, an HPF (high pass filter), an attenuation addition unit, an area element addition unit, and a first angle weight addition unit corresponding to each of the plurality of speakers,
The signal amplification unit is
amplifying the sound source signal by a constant;
The HPF is
Based on the virtual sound source coordinates r _S and the speaker coordinates r _l of the first speaker, HPFh (r _l , r _S ) is set, and the HPFh (r _l , r _S ), and
The attenuation adding section is
The absolute value of the vector from the position of the virtual sound source coordinate r _S to the position of the speaker coordinate r _l of the l-th speaker is obtained, and the reciprocal of the result obtained by squaring the absolute value is the attenuation coefficient 1/||r _l −r _S || ² and multiplying said filtered signal by said attenuation factor 1/||r _l −r _S || ² ;
The area element adding section includes:
Multiplying the signal multiplied by the attenuation addition unit by the area element ΔS _l ,
The first angle weighting unit
Based on the angle θ _l formed by the first speaker calculated by the angle calculation unit, the closer the absolute value of the formed angle θ _l is to 0° in the range from 0 to 1, the closer the value is to 1. , an angle weight w _C that takes a value closer to 0 as the absolute value of the formed angle θ _l approaches 90°, and takes a value of 0 when the absolute value of the formed angle θ _l is 0° or less or 90° or more. By setting (θ _l ) and multiplying the signal multiplied by the area element addition unit by the angle weight w _C (θ _l ), the driving signal d(r _l ) for the l-th speaker is An object-based acoustic rendering device, characterized by: An object-based acoustic rendering apparatus according to claim 1, comprising:
Further, based on the unit vector of the virtual sound source direction to the virtual sound source coordinate r _S and the unit vector of the speaker direction to the speaker coordinate r _l in all the speakers, the three speakers including the virtual sound source inside are set to VBAP ( Vector Based Amplitude Panning), the unit vectors r _n1 , r _n2 , and r _n3 of the three VBAP target speakers are obtained, and the unit vector of the virtual sound source direction to the virtual sound source coordinate r _S And based on the unit vectors r _n1 , r _n2 , and r _n3 of the three VBAP target speakers, the coefficients g _l =g _n1 , g _n2 , and g _n3 corresponding to the three VBAP target speakers are obtained, and all of the above a VBAP coefficient calculation unit that sets a coefficient g _l =0 corresponding to a speaker other than the three VBAP target speakers and outputs the coefficient g _l ;
A VBAP coefficient multiplication unit, a second angle weighting unit and an addition unit corresponding to each of the plurality of speakers,
The VBAP coefficient multiplier is
multiplying the signal multiplied by the area element addition unit by the coefficient g _l output by the VBAP coefficient calculation unit;
The second angle weighting unit
Based on the angle θ _l formed by the first speaker calculated by the angle calculation unit, the closer the absolute value of the formed angle θ _l is to 0°, the closer the value is to 0 in the range from 0 to 1. , an angle weight w _S that takes a value closer to 1 as the absolute value of the formed angle θ _l approaches 90°, and takes a value of 0 when the absolute value of the formed angle θ _l is 0° or less or 90° or more. (θ _l ) is set, and the signal multiplied by the VBAP coefficient multiplier is multiplied by the angle weight w _S (θ _l ) to generate a second drive signal,
The first angle weighting unit
By setting the angle weight w _C (θ _l ) and multiplying the signal multiplied by the area element addition unit by the angle weight w _C (θ _l ), a first drive signal is generated, and the addition A unit for generating the driving signal d(r _l ) for the l-th speaker by adding the first driving signal and the second driving signal. 3. An object-based acoustic rendering apparatus according to claim 2, wherein
The VBAP coefficient multiplier is
An object-based acoustic rendering apparatus, wherein the sound source signal is input instead of the signal multiplied by the area element adding unit, and the sound source signal is multiplied by the coefficient _gl . An object-based acoustic rendering device according to any one of claims 1 to 3,
The HPF is
With a preset parameter α, a preset filter order N, and n=0, 1, . . . , N, the following equation:

to set the HPF coefficient h _n (r _l , r _s ),
Letting x[t] and y[t] be the input and output of the HPF at time t, the input/output characteristics are:

An object-based acoustic rendering apparatus, wherein the signal amplified by the signal amplifying section is filtered using the HPF coefficient h _n (r _l , r _s ) such that: An object-based acoustic rendering device according to any one of claims 1 to 4,
The attenuation adding section is
With preset parameters β ₁ and β ₂ , the following equation:

and multiplying the _{filtered signal by the attenuation coefficient g(r l , r s )} . . A program for making a computer function as an object-based acoustic rendering device according to any one of claims 1-5.

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