CN109462811B

CN109462811B - Sound field reconstruction method, device, storage medium and device based on non-central point

Info

Publication number: CN109462811B
Application number: CN201811415607.0A
Authority: CN
Inventors: 王松; 张聪; 刘宇; 阳傲傲; 朱华东
Original assignee: Wuhan Polytechnic University
Current assignee: Wuhan Polytechnic University
Priority date: 2018-11-23
Filing date: 2018-11-23
Publication date: 2020-11-17
Anticipated expiration: 2038-11-23
Also published as: CN109462811A

Abstract

The invention discloses a sound field reconstruction method, a sound field reconstruction device, a sound field storage medium and a sound field reconstruction device based on a non-central point. In the invention, the distance between the non-center point and a preset reconstruction loudspeaker is calculated, the absolute value of the difference between the distance and a preset reference distance is calculated, the absolute values are sorted from small to large, the distance corresponding to the minimum absolute value is selected from the sorting result as the target distance, a virtual sphere taking the target distance as the radius is constructed, a virtual sound signal at the virtual point on the virtual sphere is determined, and the reconstruction sound signal to be output is determined according to the virtual sound signal. In the invention, the distance corresponding to the minimum absolute value is used as the spherical radius to construct the virtual spherical surface, and the sound field is reconstructed according to the virtual spherical surface, so that not only is the reconstruction error reduced, but also the sound field quality of the reconstructed sound field is ensured, and the technical problem that the sound field quality of the sound field reconstructed at the non-central listening point is poor is solved.

Description

Sound field reconstruction method, device, storage medium and device based on non-central point

Technical Field

The invention relates to the technical field of three-dimensional audio, in particular to a sound field reconstruction method, equipment, a storage medium and a device based on a non-central point.

Background

The sound can form a certain sound field in a certain space, and particularly for a three-dimensional (3D) audio technology, the sound source sensed by human ears can be arranged in a specific direction by reconstructing a specific sound field, so that better immersion experience and sound positioning feeling are brought to a user.

For example, the sound field may be reconstructed Based on a Vector Based Amplitude Panning (VBAP) technique, specifically, the sound field may be reconstructed using two or three speakers, and the positions of the speakers need to be on the same spherical surface, and the center of sphere is the central listening point. By using two or three loudspeakers to reconstruct the sound field, a virtual sound source can be synthesized for sound localization purposes.

The VBAP technology has a derivative technology based on this, for example, the VBAP technology can be combined with a three-dimensional translation technology based on sound pressure and particle velocity, specifically, a virtual sound source can be synthesized by three speakers to ensure that the sound pressure and particle velocity generated by the virtual sound source at the center listening point are equal to those generated by the three speakers at the center listening point, thereby ensuring the sound field quality at the center listening point.

Obviously, when the sound field is reconstructed by the VBAP technique or its derivative techniques, the reconstruction of the sound field at the center of the sphere, i.e. the center listening point, is limited due to the limitations of the techniques themselves, and if the sound field is reconstructed at the non-center listening point, the quality of the reconstructed sound field is poor. Therefore, it is considered that there is a technical problem that the sound field quality of the sound field reconstructed at the non-center listening point is poor.

The above is only for the purpose of assisting understanding of the technical aspects of the present invention, and does not represent an admission that the above is prior art.

Disclosure of Invention

The invention mainly aims to provide a sound field reconstruction method, a device, a storage medium and a device based on a non-central point, and aims to solve the technical problem that the sound field quality of a sound field reconstructed at a non-central listening point is poor.

In order to achieve the above object, the present invention provides a sound field reconstruction method based on a non-central point, which includes the following steps:

when a sound field reconstruction instruction is received, determining non-central point position information and preset initial sound image position information under a preset initial sound field according to the sound field reconstruction instruction, wherein the non-central point position information is different from the central sound image position information in the preset initial sound field;

calculating the distance between the non-central point pointed by the non-central point position information and each preset reconstruction loudspeaker;

calculating a difference value between the distance and a preset reference distance, and sequencing absolute values of the difference values in a descending order to obtain an absolute value sequencing result;

determining a target absolute value in a forward first order in the absolute value sorting result, and taking a distance corresponding to the target absolute value as a target distance;

constructing a virtual spherical surface which takes the non-central point as a spherical center and the distance between the targets as a radius, and mapping the position point of the preset reconstruction loudspeaker to a spherical surface point on the virtual spherical surface as a virtual point;

determining a virtual sound signal at the virtual point according to the preset initial sound image position information in a first preset sound field reconstruction model;

and determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the virtual sound signal in a second preset sound field reconstruction model, so as to reconstruct a sound field taking the non-central point as a center by outputting the reconstructed sound signal.

Preferably, before calculating the difference between the distance and a preset reference distance and sorting the absolute values of the differences in descending order to obtain an absolute value sorting result, the non-center point-based sound field reconstruction method further includes:

sorting the distance sorting results in a descending order to obtain distance sorting results, taking the distance in the forward first order in the distance sorting results as a first reference distance, and taking the distance in the reverse first order in the distance sorting results as a second reference distance;

and calculating the mean value of the distance between the first reference distance and the second reference distance, and taking the mean value as a preset reference distance.

Preferably, the constructing a virtual spherical surface with the non-central point as a spherical center and the target distance as a radius, and mapping the position point of the preset reconstruction speaker to a spherical point on the virtual spherical surface as a virtual point includes:

and constructing a virtual spherical surface which takes the non-central point as a spherical center and the distance between the targets as a radius, and taking an intersection point between the virtual spherical surface and a preset straight line as a virtual point, wherein the preset straight line is a straight line connecting the non-central point and a position point of the preset reconstruction loudspeaker.

Preferably, when the sound field reconstruction instruction is received, determining, according to the sound field reconstruction instruction, non-central point position information and preset initial sound image position information in a preset initial sound field, includes:

when a sound field reconstruction instruction is received, extracting non-central point position information, initial position information of a preset initial loudspeaker, an initial sound signal output by the preset initial loudspeaker and central listening point position information from the sound field reconstruction instruction, wherein the central listening point position information is used for representing the position information of a central listening point;

and constructing preset initial sound image position information with the central listening point as the center according to the initial position information and the initial sound signal.

Preferably, the first preset sound field reconstruction model comprises a preset sound image azimuth translation formula and a preset virtual sound signal determination formula;

the determining, in the first preset sound field reconstruction model, the virtual sound signal at the virtual point according to the preset initial sound image position information includes:

calculating the distance between the center listening point and the non-center point as a translation distance;

determining virtual sound image position information corresponding to the non-central point according to the preset initial sound image position information and the translation distance under the preset sound image azimuth translation formula;

and determining the virtual sound signal at the virtual point according to the virtual sound image position information and the virtual point position information of the virtual point under the preset virtual sound signal determination formula.

Preferably, the second preset sound field reconstruction model includes a preset virtual sound pressure calculation formula and a preset reconstruction sound pressure calculation formula;

determining, in a second preset sound field reconstruction model, a reconstructed sound signal to be output at the preset reconstruction speaker according to the virtual sound signal, so as to reconstruct a sound field centered on the non-central point by outputting the reconstructed sound signal, including:

determining the virtual sound pressure of the virtual sound signal at the non-central point through the preset virtual sound pressure calculation formula;

and determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the virtual sound pressure at the non-central point under the preset reconstruction sound pressure calculation formula, so as to reconstruct a sound field taking the non-central point as a center by outputting the reconstructed sound signal.

Preferably, the determining, according to the virtual sound pressure at the non-central point, a reconstructed sound signal to be output at the preset reconstruction speaker under the preset reconstruction sound pressure calculation formula, so as to reconstruct a sound field centered on the non-central point by outputting the reconstructed sound signal, includes:

determining reconstructed sound pressure constructed by the preset reconstructed loudspeaker at the non-central point according to the virtual sound pressure at the non-central point;

and determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the reconstructed sound pressure constructed at the non-central point under the preset reconstruction sound pressure calculation formula, so as to reconstruct a sound field taking the non-central point as a center by outputting the reconstructed sound signal.

Furthermore, to achieve the above object, the present invention also proposes an audio apparatus comprising a memory, a processor and a non-center point based sound field reconstruction program stored on the memory and executable on the processor, the non-center point based sound field reconstruction program being configured to implement the steps of the non-center point based sound field reconstruction method as described above.

Furthermore, to achieve the above object, the present invention also proposes a storage medium having stored thereon a non-center point based sound field reconstruction program which, when executed by a processor, implements the steps of the non-center point based sound field reconstruction method as described above.

In addition, to achieve the above object, the present invention further provides a non-center point based sound field reconstruction apparatus, including:

the instruction initiating module is used for determining non-central point position information and preset initial sound image position information under a preset initial sound field according to a sound field reconstruction instruction when the sound field reconstruction instruction is received, wherein the non-central point position information is different from the central sound image position information in the preset initial sound field;

the distance calculation module is used for calculating the distance between the non-central point pointed by the non-central point position information and each preset reconstruction loudspeaker;

the sorting module is used for calculating a difference value between the distance and a preset reference distance and sorting the absolute values of the difference values from small to large to obtain an absolute value sorting result;

a distance determining module, configured to determine, in the absolute value sorting result, a target absolute value in a forward first order, and take a distance corresponding to the target absolute value as a target distance;

the virtual point determining module is used for constructing a virtual spherical surface which takes the non-central point as a spherical center and the distance between the targets as a radius, and mapping the position point of the preset reconstruction loudspeaker to a spherical point on the virtual spherical surface as a virtual point;

the virtual sound signal generation module is used for determining a virtual sound signal at the virtual point according to the preset initial sound image position information in a first preset sound field reconstruction model;

a sound field reconstruction module, configured to determine, in a second preset sound field reconstruction model, a reconstructed sound signal to be output at the preset reconstruction speaker according to the virtual sound signal, so as to reconstruct, by outputting the reconstructed sound signal, a sound field centered on the non-central point.

The method comprises the steps of firstly calculating the distance between a non-central point and each preset reconstruction loudspeaker, then calculating the absolute value of the difference between the distance and a preset reference distance, sequencing the absolute values from small to large, taking the distance corresponding to the absolute value in the forward first sequence in the sequencing result as the target distance, constructing a virtual sphere taking the target distance as the radius, then mapping the position point of the preset reconstruction loudspeaker to a spherical point on the virtual sphere as a virtual point, finally determining a virtual sound signal at the virtual point according to the preset initial sound image position information, and determining the reconstruction sound signal to be output at the preset reconstruction loudspeaker according to the virtual sound signal so as to reconstruct the sound field. Obviously, the invention maps the position points of the preset reconstruction loudspeakers which are not on the same spherical surface to the virtual spherical surface, the virtual spherical surface takes the distance corresponding to the minimum absolute value as the spherical radius, and further the preset initial sound image position information is taken as the initial sound image reference and the virtual sound signal to determine the actually output reconstruction sound signal, which is different from the reconstruction mode of reconstructing the sound field by using the central sound listening point, and the invention realizes the construction of the sound field aiming at the non-central point, namely the non-spherical center. In addition, because the virtual spherical surface of the virtual point to be mapped is constructed by taking the preset reference distance as a reference, the possible error between the reconstructed sound field and the preset initial sound field in the actual operation scene is reduced, the sound field quality of the reconstructed sound field is ensured, and the technical problem that the sound field quality of the sound field reconstructed at the non-central listening point is poor is solved.

Drawings

FIG. 1 is a schematic diagram of an audio device in a hardware operating environment according to an embodiment of the present invention;

FIG. 2 is a schematic flow chart of a first embodiment of a non-center point-based sound field reconstruction method according to the present invention;

FIG. 3 is an orientation diagram of sound field reconstruction in an embodiment of the present invention;

FIG. 4 is a flowchart illustrating a sound field reconstruction method based on a non-center point according to a second embodiment of the present invention;

FIG. 5 is a flowchart illustrating a sound field reconstruction method based on a non-center point according to a third embodiment of the present invention;

fig. 6 is a block diagram illustrating a first embodiment of a non-center point based sound field reconstruction apparatus according to the present invention.

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an audio device in a hardware operating environment according to an embodiment of the present invention.

As shown in fig. 1, the audio device may include: a processor 1001, such as a CPU, a communication bus 1002, a user interface 1003, a network interface 1004, and a memory 1005. Wherein a communication bus 1002 is used to enable connective communication between these components. The user interface 1003 may include a Display screen (Display), and the optional user interface 1003 may further include a standard wired interface and a wireless interface, and the wired interface for the user interface 1003 may be a USB interface in the present invention. The network interface 1004 may optionally include a standard wired interface, a wireless interface (e.g., WI-FI interface). The memory 1005 may be a high-speed RAM memory or a non-volatile memory (e.g., a magnetic disk memory). The memory 1005 may alternatively be a storage device separate from the processor 1001.

Those skilled in the art will appreciate that the configuration shown in fig. 1 does not constitute a limitation of the audio device and may include more or fewer components than those shown, or some components may be combined, or a different arrangement of components.

As shown in fig. 1, a memory 1005, which is a kind of computer storage medium, may include therein an operating system, a network communication module, a user interface module, and a non-center point-based sound field reconstruction program.

In the audio device shown in fig. 1, the network interface 1004 is mainly used for connecting to a backend server and performing data communication with the backend server; the user interface 1003 is mainly used for connecting peripheral equipment; the audio apparatus calls, through the processor 1001, a non-center point-based sound field reconstruction program stored in the memory 1005, and performs the following operations:

Further, the processor 1001 may call a non-center point based sound field reconstruction program stored in the memory 1005, and further perform the following operations:

In this embodiment, the distance between the non-center point and each preset reconstruction speaker is calculated, then the absolute value of the difference between the distance and the preset reference distance is calculated, the absolute values are sorted from small to large, the distance corresponding to the absolute value in the forward first order in the sorting result is used as the target distance, a virtual sphere with the target distance as the radius is constructed, then, the position points of the preset reconstruction speakers are mapped to spherical points on the virtual sphere as virtual points, finally, the virtual sound signal at the virtual point is determined according to the preset initial sound image position information, and the reconstruction sound signal to be output at the preset reconstruction speakers is determined according to the virtual sound signal to reconstruct the sound field. Obviously, in the present embodiment, the position points of the preset reconstruction speakers that are not on the same spherical surface are mapped onto the virtual spherical surface, and the virtual spherical surface uses the distance corresponding to the minimum absolute value as the spherical radius, and further uses the preset initial sound image position information as the initial sound image reference and the virtual sound signal to determine the actually output reconstruction sound signal, which is different from the reconstruction method of reconstructing the sound field with the center sound listening point, the present embodiment implements the construction of the sound field with respect to the non-center point, i.e., the non-spherical center. In addition, because the virtual spherical surface of the virtual point to be mapped is constructed by taking the preset reference distance as a reference, the possible error between the reconstructed sound field and the preset initial sound field in the actual operation scene is reduced, the sound field quality of the reconstructed sound field is ensured, and the technical problem that the sound field quality of the sound field reconstructed at the non-central listening point is poor is solved.

Based on the hardware structure, the embodiment of the sound field reconstruction method based on the non-central point is provided.

Referring to fig. 2, fig. 2 is a schematic flow chart of a sound field reconstruction method based on a non-center point according to a first embodiment of the present invention.

In a first embodiment, the non-center point based sound field reconstruction method comprises the following steps:

step S10: when a sound field reconstruction instruction is received, determining non-central point position information and preset initial sound image position information under a preset initial sound field according to the sound field reconstruction instruction, wherein the non-central point position information is different from the central sound image position information in the preset initial sound field.

It is to be understood that the center listening point, i.e., the center of sphere, may be denoted as O, considering that when a sound field is reconstructed by the VBAP technique or its derivative technique, the sound field is reconstructed centering on the center listening point. However, when the VBAP technology is actually applied, the quality of the reconstructed sound field is poor in terms of the representation of the sound field reconstructed at an off-center listening point, i.e., an off-center position. However, by the technical solution described in this embodiment, the sound field quality of the sound field reconstructed at the non-center listening point can be greatly improved. Further, the non-center listening point may be referred to simply as a non-center point.

It should be understood that the execution subject of the present embodiment is an audio device, and the audio device may include a plurality of preset reconstruction speakers, or may not include the preset reconstruction speakers and be connected with the preset reconstruction speakers by wire or wirelessly.

In a specific implementation, when the sound field reconstruction instruction is received, a reconstruction operation for reconstructing the sound field at the non-center listening point may be performed, for example, the non-center point position information and the preset initial sound image position information in the preset initial sound field may be determined first. The non-central point position information is position information of a non-central point, the non-central point is marked as L, the preset initial sound field is an original sound field which is constructed by the preset initial loudspeaker aiming at the central listening point O, and the preset initial sound image position information is sound image azimuth information which is generated by the preset initial loudspeaker at the central listening point O.

It can be understood that, referring to fig. 3, the number of the preset initial speakers is M, where M is a positive integer, and the position information of the mth preset initial speaker can be denoted as lspo_mM is more than or equal to 1 and less than or equal to M, and M is a positive integer. Moreover, the preset initial speakers are different from the preset reconstruction speakers, and all the preset initial speakers fall on the same spherical surface, but all the preset reconstruction speakers do not necessarily fall on the same spherical surface.

Step S20: and calculating the distance between the non-central point pointed by the non-central point position information and each preset reconstruction loudspeaker.

It can be understood that, referring to fig. 3, if the number of the preset reconstructed speakers is N, and N is a positive integer, the position information of the nth preset reconstructed speaker can be recorded as lspr_nN is more than or equal to 1 and less than or equal to N, and N is a positive integer. Furthermore, the position information in the present embodiment may be expressed in the form of polar coordinates,

wherein,

is referred to as lspr_nThe distance from the central listening point O,

is referred to as lspr_nThe included angle between the projection of the connecting line of the central listening point O and the x axis,

is referred to as lspr_nAnd the connecting line with the central listening point O forms an included angle with the xOy plane. Of course, it can also be expressed in rectangular coordinates,

it should be understood that in FIG. 3, where N is 3, there is lspr₁、lspr₂And lspr₃3 preset reconstruction loudspeakers in total can respectively calculate the distance between the preset reconstruction loudspeakers and the non-central point L, and each distance can be recorded as

Step S30: and calculating the difference between the distance and a preset reference distance, and sequencing the absolute values of the difference from small to large to obtain an absolute value sequencing result.

It will be appreciated that the reconstruction speakers may be arranged at a distance apart, taking into account that they do not necessarily all lie on the same sphere centered on L

The numerical values of the spherical surface are reordered to complete the construction of the virtual spherical surface.

In a specific implementation, the reordering may be performed by first calculating the distance between the two adjacent antennas

The difference between the reference distance and a predetermined reference distance, for example, the predetermined reference distance can be recorded as R_LAnd then may be at a plurality of stand-off distances

In the searching and the preset reference distance R_LThe distance at which the value of (a) is closest is taken as the radius of the virtual sphere. For example, referring to fig. 3, if the preset reference distance R is preset_LIs exactly equal to the preset reconstruction loudspeaker lspr₂Distance from non-central point L

Then

It should be understood that in order to find the distance R from the preset reference distance R_LThe distance of the closest value of (a) can be calculated

Is away from a preset reference distance R_LThe difference between them, and the absolute value of the difference is obtained and can be recorded as

Referring to FIG. 3, the sum can be calculated

Corresponding to

And

corresponding to

And with

Corresponding to

As is apparent from the above description of the preferred embodiment,

the obtained set of absolute value ordering results is

Furthermore, as can be seen from FIG. 3, since

Therefore, the first and second electrodes are formed on the substrate,

the value of (b) is actually 0.

Step S40: and determining a target absolute value in a forward first order in the absolute value sorting result, and taking a distance corresponding to the target absolute value as a target distance.

It should be understood that, considering that there may be a certain error between the preset initial sound field as a reference and the finally constructed reconstructed sound field, and the preset initial sound field and the finally constructed reconstructed sound field are not necessarily completely fit with each other, the distance with the minimum calculated absolute value may be selected

As the spherical radius for constructing the virtual sphere. Obviously, a predetermined preset reference distance R is set_LThe spherical radius is used as the selection basis, so that the error property can be greatly reduced.

In particular implementations, the distance of separation in the forward first order in the set of absolute value sorted results may be

Corresponding distance of separation

A virtual sphere is constructed as a radius.

Step S50: and constructing a virtual spherical surface which takes the non-central point as a spherical center and the distance between the targets as a radius, and mapping the position point of the preset reconstruction loudspeaker to a spherical surface point on the virtual spherical surface as a virtual point.

It should be understood that the same applies if

I.e. L and preset reconstruction loudspeaker lspr₂The distance between the two speakers is used as a radius to construct a virtual sphere, and all the preset reconstructed speakers lspr can be used_nAre mapped into the virtual sphere to obtain the corresponding lspr₁Corresponding virtual point and corresponding lspr₃Corresponding virtual points, all three of which are shown in FIG. 3, andfalling on the sphere depicted in fig. 3. Due to the fact that

lspr₂Falls on the sphere itself, so it is equal to lspr₂The corresponding virtual point is lspr₂Itself.

It will be appreciated that the virtual point can be denoted as lspv_nAnd, if expressed in polar coordinate form,

is lspv_nThe distance between the non-central point L,

refers to lspv_nThe included angle between the projection of the line connecting the non-central point and the x-axis,

refers to lspv_nAnd a clip between a line connecting the non-center point L and the xOy plane; if expressed in the form of rectangular coordinates,

step S60: and determining a virtual sound signal at the virtual point according to the preset initial sound image position information in a first preset sound field reconstruction model.

It will be appreciated that in determining the virtual point lspv_nThe speaker assumed to be at the virtual point may be referred to as a virtual speaker, and the sound signal emitted by the virtual speaker may be referred to as a virtual sound signal. Therefore, the virtual sound signal emitted by the corresponding virtual speaker can be determined by the first preset sound field reconstruction model using the preset initial sound image position information as a reference.

Step S70: and determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the virtual sound signal in a second preset sound field reconstruction model, so as to reconstruct a sound field taking the non-central point as a center by outputting the reconstructed sound signal.

It should be understood that after determining the virtual sound signals emitted by the virtual loudspeakers on the same sphere, the virtual point lspv can be reconstructed in a second predetermined sound field reconstruction model_nThe virtual loudspeaker at (a) is transformed to be actually present in lspr_nAnd the preset reconstruction loudspeaker is used for finally determining a reconstruction sound signal to be actually output by the preset reconstruction loudspeaker, and constructing a sound field taking the non-central point L as the center through the reconstruction sound signal.

Referring to fig. 4, fig. 4 is a flowchart illustrating a sound field reconstruction method based on a non-center point according to a second embodiment of the present invention, and the sound field reconstruction method based on a non-center point according to the second embodiment of the present invention is proposed based on the first embodiment illustrated in fig. 2.

In a second embodiment, before calculating a difference between the distance and a preset reference distance and sorting absolute values of the difference in descending order to obtain an absolute value sorting result, the non-center point-based sound field reconstruction method further includes:

It can be understood that, for the preset reference distance, the maximum distance and the minimum distance may be considered together to determine the value of the preset reference distance, so as to further reduce the error that may occur between the reconstructed sound field and the preset initial sound field, and improve the sound field quality of the reconstructed sound field.

In a specific implementation, see FIG. 3, there is lspr₁、lspr₂And lspr₃3 preset reconstruction loudspeakers in total, and the corresponding distance

Are respectively as

And

obviously, according to the illustration in FIG. 3, the obtained distance sorting result set is

The distance between the first cis position and the second cis position in the forward direction is the shortest distance

The distance between the first and second forward directions is the longest distance

The arithmetic mean of the two can be calculated

The arithmetic mean shown in FIG. 3 happens to be

By setting the mean value to a preset reference distance R_LMeanwhile, the longest distance and the shortest distance in a real scene are considered, so that the error possibly occurring can be greatly reduced, and the reconstructed sound field can be closer to the preset initial sound field.

Further, the constructing a virtual sphere with the non-center point as a sphere center and the target distance as a radius, and mapping the position point of the preset reconstruction speaker to a spherical point on the virtual sphere as a virtual point includes:

In a specific implementation, in order to determine the virtual point mapped on the virtual sphere, a connection between the non-central point L and a plurality of preset reconstructed speakers lspr may be established_nAs can be seen in fig. 3, the predetermined straight lines are shown in the form of dashed lines. By presettingThe straight line intersects with the virtual spherical surface, and the intersection point intersected with the virtual spherical surface is the virtual point lspv_nVirtual point lspv_nMarked as a hollow circle, lspr, in FIG. 3_nAnd lspo_mMarked as a filled circle.

Further, the step S10 includes:

step S101: when a sound field reconstruction instruction is received, extracting non-central point position information, initial position information of a preset initial loudspeaker, an initial sound signal output by the preset initial loudspeaker and central listening point position information from the sound field reconstruction instruction, wherein the central listening point position information is used for representing the position information of a central listening point.

It will be appreciated that the initial loudspeaker is preset as shown in figure 3, with the initial loudspeaker lspo being preset_mMay be expressed in polar coordinates,

point lspo_mThe distance from the central listening point O,

is pointing at lspo_mThe included angle between the projection of the connecting line of the central listening point O and the x axis,

is pointing at lspo_mAnd the angle between the line connecting the center listening point O and the xOy plane. Of course, it can also be expressed in rectangular coordinates,

it should be understood that in fig. 3, M ═ 4, there is lspo₁、lspo₂、lspo₃And lspo₄There are 4 preset initial speakers.

It will be appreciated that the initial loudspeaker lspo is preset_mThe output initial sound signal is recorded as S, and the position information of the center listening point is the position information of the center listening point O.

Step S102: and constructing preset initial sound image position information with the central listening point as the center according to the initial position information and the initial sound signal.

It is understood that the preset initial sound image position information is sound image azimuth information generated by the preset initial speaker at the center sound listening point O, and in order to obtain the preset initial sound image position information, the preset initial sound image position information may be based on the initial position information lspo_mThe preset initial sound image position information is obtained with the initial sound signal S.

In a specific implementation, the preset initial sound image position information may be calculated by a preset initial sound image calculation formula, which is,

wherein D is_oIn order to preset the initial sound image position information,

m is more than or equal to 1 and less than or equal to M, M is a positive integer, and S is an initial acoustic signal in a frequency domain.

Furthermore, the azimuth represented by the initial position information is located on a spherical surface with the center listening point as a sphere center.

It will be appreciated that the initial position information characterizes the square point lspo_mOn a spherical surface centered on the central listening point O, but with the location point lspr of the reconstruction speaker preset_nNot all of them are on a spherical surface centered on the non-center point L.

Further, the first preset sound field reconstruction model comprises a preset sound image azimuth translation formula and a preset virtual sound signal determination formula.

The step S60 includes:

step S601: and calculating the distance between the center listening point and the non-center point as a translation distance.

It is to be understood that, in order to acquire the virtual sound signal at the virtual point, the virtual sound image position information may be determined based on the preset initial sound image position information, and then the virtual sound signal at the virtual point may be determined based on the virtual sound image position information.

It should be understood that the translation distance between the central listening point O and the non-central point L can be calculated, and if the central listening point O is located at the origin (0, 0, 0) of the coordinate system, the non-central point L can be marked as (x)_L,y_L,z_L) Then the calculated translation distance between two points is also (x)_L,y_L,z_L)。

Of course, the non-center point L may be expressed as (x) in rectangular coordinates other than_L,y_L,z_L) In addition, the non-center point L can also be expressed in polar coordinate form as

Wherein R is_LIs the distance, θ, between the non-center point L and the origin O_LIs the included angle between the projection of the connecting line of the non-central point L and the origin O on the x axis and the x axis,

is the angle between the connecting line of the non-central point L and the origin O and the xOy plane.

Step S602: and determining virtual sound image position information corresponding to the non-central point according to the preset initial sound image position information and the translation distance under the preset sound image azimuth translation formula.

It can be understood that the preset initial sound image position information is sound image azimuth information generated by the preset initial loudspeaker at the central sound listening point O, and the preset initial sound image position information can be recorded as D_oThrough the pair D_oThe panning may result in sound image position information generated by the virtual speaker at a non-center point L.

In a specific implementation, the preset sound image azimuth translation formula is,

D_v＝D_o-(x_L,y_L,z_L)，

D_vrepresenting virtual sound-image position information, D_oRepresenting preset initial sound image position information, (x)_L,y_L,z_L) The panning distance is expressed, and the virtual sound image position information generated by the virtual loudspeaker at the non-central point L can be determined through the sound image azimuth panning formula.

Step S603: and determining the virtual sound signal at the virtual point according to the virtual sound image position information and the virtual point position information of the virtual point under the preset virtual sound signal determination formula.

It will be appreciated that the preset virtual sound signal determination formula is,

wherein D is_vRepresenting virtual sound image position information, lspv_nVirtual point position information representing a virtual point,

while

Representing a virtual sound signal emitted by a loudspeaker at a virtual point,

is lspv₁A virtual sound signal emitted by a loudspeaker at a point,

is lspv₂Virtual sound signals emitted by loudspeakers at points, etc.

It will be appreciated that the resulting virtual sound signal may be represented as,

obviously, by combining the preset acoustic image azimuth panning formula with the preset virtualAnd the sound signal determination formula is used for determining a virtual sound signal at the virtual point by taking the sound image position information as a reference. Specifically, the initial sound image position information D is preset under the preset sound image azimuth translation formula_oTo define virtual sound image position information D_vAnd the sound field quality is ensured.

In this embodiment, the virtual sound signal at the virtual point can be better determined by combining the preset sound image azimuth translation formula and the preset virtual sound signal determination formula, so as to indirectly ensure the sound field quality of the sound field reconstructed by the reconstructed sound signal to be output at the final preset reconstructed speaker.

Referring to fig. 5, fig. 5 is a flowchart illustrating a sound field reconstruction method based on a non-center point according to a third embodiment of the present invention, and the sound field reconstruction method based on a non-center point according to the third embodiment of the present invention is proposed based on the first embodiment shown in fig. 2.

In a third embodiment, the second preset sound field reconstruction model includes a preset virtual sound pressure calculation formula and a preset reconstruction sound pressure calculation formula.

The step S70 includes:

step S701: determining a virtual sound pressure of the virtual sound signal at the non-center point by the preset virtual sound pressure calculation formula.

It will be appreciated that after the virtual sound signal has been acquired, the virtual sound signal may be represented as

And, the number of the virtual sound signals is N, so that they are respectively slave

To

。

It should be understood that, in order to facilitate the application of the preset virtual sound pressure calculation formula, the virtual sound signal in the frequency domain may be transformed into the time domain to obtain the virtual sound signal in the time domain, so that the virtual sound signal in the time domain may be obtained

Is transformed into s_n(t) are each independently from s₁(t) to s_N(t) of (d). As for the preset virtual sound pressure calculation formula,

wherein, pv_n(L, t) is expressed as a virtual point lspv_nSound pressure, s generated by the virtual loudspeaker at the non-central point L_n(t) is a virtual sound signal in the time domain, L represents position information of a non-central point, lspv_nPosition information of the virtual point is shown, and c represents a sound velocity.

Step S702: and determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the virtual sound pressure at the non-central point under the preset reconstruction sound pressure calculation formula, so as to reconstruct a sound field taking the non-central point as a center by outputting the reconstructed sound signal.

In a particular implementation, the virtual sound pressure pv at the non-center point of the virtual speaker at the virtual point is obtained_nAfter (L, t), the virtual sound pressure may be realistically realized based on the reconstructed acoustic signal output from the preset reconstruction speaker. Specifically, the preset reconstruction sound pressure calculation formula is,

wherein, pr_n(L, t) is expressed as the sound pressure generated by the preset reconstruction speaker at the non-central point L, g_n(t) for the reconstructed acoustic signal to be output by the preset reconstruction loudspeaker, L represents the position information of the non-central point, lspr_nRepresenting the position information of the preset reconstruction speaker, and c is the sound velocity.

It will be appreciated that by mixing pv_nThe value of (L, t) is given pr_n(L, t), i.e. g can be determined_n(t) of (d). Obviously, the time t for emitting the reconstructed acoustic signal is adjusted to obtain the to-be-output signals corresponding to the preset reconstructed loudspeakersThe sound field can be reconstructed at a non-central point by outputting the reconstructed sound signal.

Further, the determining, according to the virtual sound pressure at the non-central point, a reconstructed sound signal to be output at the preset reconstruction speaker under the preset reconstruction sound pressure calculation formula, so as to reconstruct a sound field centered on the non-central point by outputting the reconstructed sound signal, includes:

It will be appreciated that the introduction of pv_n(L,t)＝pr_n(L, t), then the reconstructed sound pressure pr of the preset reconstructed loudspeaker constructed at the non-central point L can be determined_n(L,t)。

It should be understood that the preset virtual sound pressure calculation formula, the preset reconstruction sound pressure calculation formula and pv are combined_n(L,t)＝pr_n(L, t) is obtained by,

obviously, the reconstructed acoustic signal g outputtable at the preset reconstructed loudspeaker can be finally determined_n(t)。

In this embodiment, the reconstructed sound field can be reconstructed from the reconstructed sound signal to be finally output, and the reconstructed sound field has a sound field quality close to that of the initial sound field constructed from the initial sound signal at the central listening point O at the non-central point L.

Furthermore, an embodiment of the present invention further provides a storage medium, on which a non-center point based sound field reconstruction program is stored, where the non-center point based sound field reconstruction program, when executed by a processor, implements the following operations:

Further, the non-center point based sound field reconstruction program when executed by the processor further performs the following operations:

In addition, referring to fig. 6, an embodiment of the present invention further provides a sound field reconstruction apparatus based on a non-central point, where the sound field reconstruction apparatus based on a non-central point includes:

the instruction initiating module 10 is configured to, when a sound field reconstruction instruction is received, determine, according to the sound field reconstruction instruction, non-central point position information and preset initial sound image position information in a preset initial sound field, where the non-central point position information is different from center sound image position information in the preset initial sound field.

And the distance calculating module 20 is configured to calculate a distance between the non-center point pointed by the non-center point position information and each preset reconstruction speaker.

And the sorting module 30 is configured to calculate a difference between the distance and a preset reference distance, and sort the absolute values of the differences in a descending order to obtain an absolute value sorting result.

A distance determining module 40, configured to determine, in the absolute value sorting result, a target absolute value in the forward first order, and take a distance corresponding to the target absolute value as a target distance.

And a virtual point determining module 50, configured to construct a virtual spherical surface with the non-central point as a spherical center and the target distance as a radius, and map the position point of the preset reconstruction speaker to a spherical point on the virtual spherical surface as a virtual point.

A virtual sound signal generating module 60, configured to determine, in a first preset sound field reconstruction model, a virtual sound signal at the virtual point according to the preset initial sound image position information.

A sound field reconstruction module 70, configured to determine, in a second preset sound field reconstruction model, a reconstructed sound signal to be output at the preset reconstruction speaker according to the virtual sound signal, so as to reconstruct a sound field centered on the non-central point by outputting the reconstructed sound signal.

In an embodiment, the non-center point based sound field reconstruction apparatus further includes:

a reference distance determining module, configured to sort the distance distances in a descending order to obtain distance sorting results, take a distance in a forward first order in the distance sorting results as a first reference distance, and take a distance in a reverse first order in the distance sorting results as a second reference distance; and calculating the mean value of the distance between the first reference distance and the second reference distance, and taking the mean value as a preset reference distance.

In an embodiment, the virtual point determining module 50 is further configured to construct a virtual spherical surface with the non-center point as a spherical center and the target distance as a radius, and use an intersection point between the virtual spherical surface and a preset straight line as a virtual point, where the preset straight line is a straight line connecting the non-center point and the position point of the preset reconstructed speaker.

In an embodiment, the instruction initiating module 10 is further configured to, when a sound field reconstruction instruction is received, extract non-central point position information, initial position information of a preset initial speaker, an initial sound signal output by the preset initial speaker, and center listening point position information from the sound field reconstruction instruction, where the center listening point position information is used to represent position information of a center listening point; and constructing preset initial sound image position information with the central listening point as the center according to the initial position information and the initial sound signal.

In an embodiment, the virtual sound signal generating module 60 is further configured to calculate a distance between the center listening point and the non-center point as a translation distance; determining virtual sound image position information corresponding to the non-central point according to the preset initial sound image position information and the translation distance under the preset sound image azimuth translation formula; and determining the virtual sound signal at the virtual point according to the virtual sound image position information and the virtual point position information of the virtual point under the preset virtual sound signal determination formula.

In an embodiment, the sound field reconstructing module 70 is further configured to determine a virtual sound pressure of the virtual sound signal at the non-central point through the preset virtual sound pressure calculation formula; and determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the virtual sound pressure at the non-central point under the preset reconstruction sound pressure calculation formula, so as to reconstruct a sound field taking the non-central point as a center by outputting the reconstructed sound signal.

In an embodiment, the sound field reconstructing module 70 is further configured to determine a reconstructed sound pressure, which is constructed by the preset reconstructing loudspeaker at the non-central point, according to the virtual sound pressure at the non-central point; and determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the reconstructed sound pressure constructed at the non-central point under the preset reconstruction sound pressure calculation formula, so as to reconstruct a sound field taking the non-central point as a center by outputting the reconstructed sound signal.

Other embodiments or specific implementation manners of the sound field reconstruction apparatus based on the non-central point may refer to the above method embodiments, and are not described herein again.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or system. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or system that comprises the element.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments. In the unit claims enumerating several means, several of these means may be embodied by one and the same item of hardware. The use of the words first, second, third, etc. do not denote any order, but rather the words first, second, third, etc. are to be interpreted as names.

Through the above description of the embodiments, those skilled in the art will clearly understand that the method of the above embodiments can be implemented by software plus a necessary general hardware platform, and certainly can also be implemented by hardware, but in many cases, the former is a better implementation manner. Based on such understanding, the technical solutions of the present invention may be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling a terminal device (such as a mobile phone, a computer, a server, an air conditioner, or a network device) to execute the method according to the embodiments of the present invention.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by using the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A sound field reconstruction method based on a non-central point is characterized by comprising the following steps:

2. The non-center point based sound field reconstruction method according to claim 1, wherein before calculating the difference between the distance and a preset reference distance and sorting the absolute values of the difference from small to large to obtain an absolute value sorting result, the non-center point based sound field reconstruction method further comprises:

3. The method for reconstructing a sound field based on an un-centered point as claimed in claim 1, wherein said constructing a virtual sphere with the un-centered point as a center of the sphere and the target distance as a radius, and mapping the location points of the preset reconstructed speakers to spherical points on the virtual sphere as virtual points comprises:

4. The non-center point-based sound field reconstruction method according to claim 1, wherein the determining, when receiving a sound field reconstruction instruction, non-center point position information and preset initial sound image position information under a preset initial sound field according to the sound field reconstruction instruction comprises:

5. The non-center point-based sound field reconstruction method according to claim 4, wherein the first predetermined sound field reconstruction model comprises a predetermined sound image azimuth panning formula and a predetermined virtual sound signal determination formula;

6. The non-center point based sound field reconstruction method according to claim 1, wherein the second predetermined sound field reconstruction model includes a predetermined virtual sound pressure calculation formula and a predetermined reconstruction sound pressure calculation formula;

7. The non-center-point-based sound field reconstruction method according to claim 6, wherein the determining a reconstructed sound signal to be output at the preset reconstruction speaker according to the virtual sound pressure at the non-center point under the preset reconstruction sound pressure calculation formula to reconstruct the sound field centered on the non-center point by outputting the reconstructed sound signal comprises:

8. An audio device, characterized in that the audio device comprises: memory, a processor and a non-center point based sound field reconstruction program stored on the memory and executable on the processor, the non-center point based sound field reconstruction program when executed by the processor implementing the steps of the non-center point based sound field reconstruction method according to any one of claims 1 to 7.

9. A storage medium having stored thereon a non-center point based sound field reconstruction program, which when executed by a processor implements the steps of the non-center point based sound field reconstruction method according to any one of claims 1 to 7.

10. A non-center point based sound field reconstruction apparatus, the non-center point based sound field reconstruction apparatus comprising: