CN109618276B

CN109618276B - Sound field reconstruction method, device, storage medium and device based on non-central point

Info

Publication number: CN109618276B
Application number: CN201811415550.4A
Authority: CN
Inventors: 王松; 张聪
Original assignee: Wuhan Polytechnic University
Current assignee: Wuhan Polytechnic University
Priority date: 2018-11-23
Filing date: 2018-11-23
Publication date: 2020-08-07
Anticipated expiration: 2038-11-23
Also published as: CN109618276A

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. The method comprises the steps of calculating the distance between a non-center point and a reconstruction loudspeaker, constructing a virtual spherical surface based on the distance, mapping a position point of the reconstruction loudspeaker to a spherical point on the virtual spherical surface to serve as a virtual point to be selected, determining a virtual sound signal to be selected at the virtual point to be selected, selecting a target virtual sound signal according to a sound field of an initial non-center area, and determining the reconstruction sound signal to be output according to the target virtual sound signal. Therefore, the target virtual sound signals are selected from the multiple virtual sound signals to be selected according to the initial non-central area sound field, and the quality of the finally obtained sound field can be better in the screening link. Therefore, the sound field can be constructed by using the non-central point, namely the non-spherical center, aiming at the loudspeakers which are not positioned on the same spherical surface, the quality of the sound field is improved, and the technical problem that the 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

Conventionally, sound signals may be output to reconstruct a specific sound field and to set a sound source perceived by human ears in a specific orientation, which may bring a better sound localization feeling and an immersive listening experience to a user.

As for the way of reconstructing the sound field, there are many ways, for example, the sound field can be reconstructed based on Vector based amplitude phase shift (VBAP) technology, specifically, the sound field can be reconstructed by 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.

Of course, sound field reconstruction can also be completed based on a derivative technology of VBAP technology, specifically, a virtual sound source is synthesized by a plurality of 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 plurality of speakers at the center listening point, so that the sound field quality at the center listening point is ensured.

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 initial position information of a preset initial loudspeaker 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 listening point 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;

respectively constructing a virtual spherical surface to be selected by taking the distance as a radius, and mapping the position point of the preset reconstruction loudspeaker to be a spherical surface point on the virtual spherical surface to be selected as a virtual point to be selected;

determining a virtual sound signal to be selected output at the virtual point to be selected according to the preset initial sound image position information under the preset initial sound field;

selecting a target virtual sound signal from the virtual sound signals to be selected according to an initial non-central area sound field constructed by the preset initial loudspeaker in a preset non-central area in a sound pressure error selection model, wherein the preset non-central area is a spherical area with the non-central point as a center;

and determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the target virtual sound signal in a 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, the sound pressure error selection model comprises a preset initial sound pressure calculation formula, a preset area sound pressure calculation formula and a preset mean square error calculation formula;

selecting a target virtual sound signal from the virtual sound signals to be selected in the sound pressure error selection model according to an initial non-central area sound field constructed by the preset initial loudspeaker in a preset non-central area, wherein the selecting comprises the following steps:

determining initial sound pressure in a preset non-central area according to initial position information of the preset initial loudspeaker in the preset initial sound pressure calculation formula, and determining an initial non-central area sound field corresponding to the initial sound pressure;

determining the sound pressure of the non-central area to be selected in the preset non-central area according to the virtual point to be selected and the virtual sound signal to be selected in the preset area sound pressure calculation formula, and determining each sound field of the non-central area to be selected corresponding to the sound pressure of the non-central area to be selected;

determining a corresponding error value to be selected according to the initial non-central area sound field and the non-central area sound field to be selected in the preset mean square error calculation formula;

and selecting a target error value from the error values to be selected, and determining a target virtual sound signal corresponding to the target error value.

Preferably, the respectively constructing a virtual sphere to be selected by using the distance as a radius, and mapping the position point of the preset reconstructed speaker to be a spherical point on the virtual sphere to be selected as a virtual point to be selected includes:

constructing a virtual spherical surface to be selected by taking the non-central point as a spherical center and the distance as a radius;

and taking an intersection point between the virtual spherical surface to be selected and a preset straight line as a virtual point to be selected, wherein the preset straight line is a straight line connecting the non-central point and the 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 initial position information of a preset initial speaker in a preset initial sound field, includes:

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

before determining the virtual sound signal to be selected output at the virtual point to be selected according to the preset initial sound image position information in the preset initial sound field, the sound field reconstruction method based on the non-central point further includes:

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 determining, according to the preset initial sound image position information in the preset initial sound field, the to-be-selected virtual sound signal output at the to-be-selected virtual point includes:

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

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

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

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

determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the target virtual sound signal in a 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, wherein the method comprises the following steps:

determining the virtual sound pressure of the target 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 initial position information of a preset initial loudspeaker 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 listening point 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 virtual point determining module is used for respectively constructing virtual spherical surfaces to be selected by taking the distance as a radius, and mapping the position points of the preset reconstruction loudspeaker to spherical points on the virtual spherical surfaces to be selected as virtual points to be selected;

the virtual sound signal generation module is used for determining a virtual sound signal to be selected output at the virtual point to be selected according to the preset initial sound image position information in the preset initial sound field;

the virtual sound signal selection module is used for selecting a target virtual sound signal from the virtual sound signals to be selected in a sound pressure error selection model according to an initial non-central area sound field constructed by the preset initial loudspeaker in a preset non-central area, wherein the preset non-central area is a spherical area with the non-central point as the center;

and the sound field reconstruction module is used for determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the target virtual sound signal in a 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.

In the invention, the distance between a non-central point and each preset reconstruction loudspeaker is calculated firstly, and a plurality of virtual spherical surfaces to be selected are constructed on the basis of the distance; then, mapping the position point of a preset reconstruction loudspeaker to a spherical point on a virtual sphere to be selected as a virtual point to be selected, and finally determining a virtual sound signal to be selected at the virtual point to be selected according to the preset initial sound image position information; and selecting a target virtual sound signal from the virtual sound signals to be selected by taking the initial non-central area sound field as a basis, and determining a reconstructed sound signal to be output at a preset reconstructed loudspeaker according to the target virtual sound signal so as to reconstruct the sound field. Different from a reconstruction mode of reconstructing a sound field by using a central listening point, the invention not only realizes the construction of the sound field aiming at a non-central point, namely a non-spherical center, but also improves the sound field quality of the reconstructed sound field and solves the technical problem of poor sound field quality of the sound field reconstructed at the non-central listening point.

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:

accordingly, the following operations are also performed:

In this embodiment, the distance between the non-center point and each preset reconstruction speaker is calculated first, and a plurality of virtual spheres to be selected are constructed based on the distance; then, mapping the position point of a preset reconstruction loudspeaker to a spherical point on a virtual sphere to be selected as a virtual point to be selected, and finally determining a virtual sound signal to be selected at the virtual point to be selected according to the preset initial sound image position information; and selecting a target virtual sound signal from the virtual sound signals to be selected by taking the initial non-central area sound field as a basis, and determining a reconstructed sound signal to be output at a preset reconstructed loudspeaker according to the target virtual sound signal so as to reconstruct the sound field. Different from a reconstruction mode of reconstructing a sound field by using a center listening point, the embodiment not only realizes the construction of the sound field aiming at a non-central point, namely a non-spherical center, but also improves the sound field quality of the reconstructed sound field, and solves the technical problem that the sound field quality of the sound field reconstructed at the non-central listening point is poor.

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 initial position information of a preset initial loudspeaker 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 listening point position information in the preset initial sound field.

It is understood that considering that the VBAP technique reconstructs a sound field to reconstruct the sound field with a center listening point as a center, the center listening point, i.e., the center of sphere, can be recorded as O. 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 a sound field reconstruction instruction is received, a reconstruction operation of reconstructing a sound field at a non-central listening point may be performed, for example, location information of a non-central point and initial location information of a preset initial speaker in a preset initial sound field may be determined, where the location information of the non-central point is location information of the non-central point, the non-central point is recorded as L, the preset initial sound field is an original sound field constructed by the preset initial speaker for the central listening point O, and the initial location information of the preset initial speaker records a location point of the preset initial speaker.

It can be understood that, referring to fig. 3, the number of preset initial speakers is M, where M is a positive integer, and the initial 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, the distance between the preset reconstruction loudspeakers and the non-central point L can be respectively calculated, and the distance can be recorded as d_n。

Step S30: and respectively constructing a virtual spherical surface to be selected by taking the distance as a radius, and mapping the position point of the preset reconstruction loudspeaker to be a spherical surface point on the virtual spherical surface to be selected as a virtual point to be selected.

It will be appreciated that the plurality of stand-off distances d are such that the reconstruction speakers are not all on the same spherical surface centered at L, taking into account that they are not all on the same spherical surface_nThe values of (a) are not equal. For example, see FIG. 3, d in FIG. 3_nIs d₁＜d₂＜d₃。

It should be understood that, considering that there is a certain error between the preset initial sound field as a reference and the finally constructed reconstructed sound field, the distance d at which the sound field quality of the finally reconstructed sound field is optimal is selected_jJ is more than or equal to 1 and less than or equal to N, and j is a positive integer. Therefore, a plurality of virtual spherical surfaces can be constructed for subsequent preference.

It will be understood that if d is used₁I.e. L with the preset reconstruction loudspeaker lspr₁The distance between the two spherical surfaces is used as a radius to construct a virtual spherical surface, and the obtained virtual spherical surface can be recorded as L₁. By analogy, d will also be obtained₂As a radius to be selected virtual sphere L₂And with d₃As a radius to be selected virtual sphere L₃Total 3 virtual spherical surfaces L to be selected_j。

It should be understood that the virtual sphere L is to be selected upon completion_jIf the virtual sphere L is to be selected after construction₁For example, all the preset reconstruction speakers lspr may also be used_nAre all mapped to the virtual sphere L₁To obtain the corresponding derivatives with lspr₂Corresponding virtual point and corresponding lspr₃The corresponding virtual point. Due to lspr₁Falls on the sphere itself, so it is equal to lspr₁The corresponding virtual point is lspr₁Itself.

It is understood that a virtual point may be noted as

If expressed in the form of polar coordinates,

is composed of

The distance from the non-center point L,

means that

The angle between the projection of the line connecting the non-center point L on the x-axis and the x-axis,

means that

And the line connecting the non-center point L with the xOy plane, if expressed in rectangular coordinates,

obviously, since then d will be given₁As a radius to be selected virtual sphere L₁For example, therefore, the corresponding virtual point is

As can be seen, each virtual sphere L to be selected_jAll willA group of 3 virtual points to be selected

Step S40: and determining the virtual sound signal to be selected output at the virtual point to be selected according to the preset initial sound image position information in the preset initial sound field.

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 listening point O. In determining virtual points to be selected

The speaker assumed to be at the virtual point to be selected may be referred to as a virtual speaker, and the acoustic signal emitted by the virtual speaker may be referred to as a virtual acoustic signal. Therefore, the virtual sound signal to be selected emitted by the corresponding virtual speaker can be determined by taking the preset initial sound image position information as a reference.

Step S50: and selecting a target virtual sound signal from the virtual sound signals to be selected in a sound pressure error selection model according to an initial non-central area sound field constructed by the preset initial loudspeaker in a preset non-central area, wherein the preset non-central area is a spherical area taking the non-central point as a center.

It is understood that there are a plurality of virtual spheres L to be selected_jThen correspond to multiple groups of virtual points to be selected

And then there are a plurality of corresponding virtual sound signals to be selected, and in order to select the optimal virtual sound signal from the virtual sound signals to reconstruct the reconstructed sound field with the minimum error, the virtual sound signals can be screened.

In a specific implementation, an initial non-central area sound field generated by a preset initial speaker at a preset non-central area is used as a reference, an area sound field closer to the initial non-central area sound field is selected from a plurality of area sound fields constructed by virtual sound signals to be selected, and the virtual sound signals to be selected corresponding to the closer area sound field are used as target virtual sound signals, wherein the preset non-central area is a spherical area with a non-central point L as a center, and specifically, the preset non-central area is a non-central listening area with a non-central point L as a center and a human head radius of 8.5 centimeters as a radius.

It should be understood that, in order to select the target virtual sound signal, the filtering criterion in this embodiment will be the initial non-central region sound field.

Step S60: and determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the target virtual sound signal in a 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 target virtual sound signal emitted by the virtual speakers on the same sphere, the virtual speakers at the virtual points can be converted to actually exist in lspr in the preset sound field reconstruction model_nTo finally determine the reconstructed acoustic signal that the preset reconstructed speaker actually outputs, and to construct a sound field centered on the non-center point L from the reconstructed acoustic 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, the sound pressure error selection model includes a preset initial sound pressure calculation formula, a preset area sound pressure calculation formula, and a preset mean square error calculation formula;

It can be understood that, because there are multiple sets of virtual sound signals to be selected, in order to select the optimal virtual sound signal from the virtual sound signals to reconstruct a sound field with the smallest error compared with the sound field in the initial non-central area, the initial non-central area sound field can be used as a screening basis to screen the virtual sound signals.

In a specific implementation, initial position information lspo of a preset initial loudspeaker is obtained_mThen, the preset initial speaker can be calculatedSpecifically, initial sound pressure may be determined first from the initial position information, and then the sound field may be determined based on the initial sound pressure, the initial sound pressure may be obtained based on a preset initial sound pressure calculation formula,

wherein, p (β)_x,β_y,β_z) At point β ═ (β)_x,β_y,β_z) Initial sound pressure of (β) ═ β_x,β_y,β_z) For presetting arbitrary listening points, lspo, in non-central regions_mThe initial position information of the initial speaker is preset, S is an initial sound signal generated by the initial speaker when the initial sound field is constructed, and S is a frequency domain signal.

It should be understood that, after obtaining the initial sound pressure of any listening point in the preset non-center region, the initial sound pressure may be summed in the range of the preset non-center region to obtain an initial non-center region sound field S corresponding to the preset non-center region_d。

It will be appreciated that the sound field S is obtained in the initial non-central region_dAnd then, the sound field of each non-central area to be selected can be calculated. Specifically, the sound pressure of the non-central area to be selected is determined through the virtual point to be selected and the virtual sound signal to be selected, and then the sound field is determined based on the sound pressure of the non-central area to be selected. As for the sound pressure of the non-central area to be selected, it is obtained based on a preset area sound pressure calculation formula, which is,

wherein p is_j(β_x,β_y,β_z) At point β ═ (β)_x,β_y,β_z) To-be-selected non-center region sound pressure of (β) ═ β_x,β_y,β_z) To preset any listening point in the non-central region,

in order to have a virtual point to be selected,

a virtual sound signal generated for a virtual speaker.

It should be understood that, after obtaining the sound pressure of the to-be-selected non-central region of any listening point in the preset non-central region, the sound pressure of the to-be-selected non-central region may be summed within the range of the preset non-central region to obtain each to-be-selected non-central region sound field corresponding to the preset non-central region

It will be appreciated that the initial non-central region sound field S is obtained_dWith a plurality of sound fields of non-central areas to be selected

Then, in order to select the sound field of the non-central area from a plurality of sound fields to be selected

Middle screening out sound field S most close to initial non-central region_dThe non-central region sound field of (2) may be calculated based on a predetermined mean square error calculation formula. As for the predetermined mean square error calculation formula,

wherein E is_jIn order to have an error value to be selected,

to select a non-center region sound field, S_dIs the initial non-central region sound field.

It should be understood that the error value E may be selected from a plurality of values to be selected_jSelecting an error value as a target error value, and further selecting a virtual sound signal corresponding to the target error value

As a target virtual sound signal. Specifically, the error values to be selected may be sorted in order from small to large to obtain an error value sorting result, the error value to be selected in the error value sorting result in the first order in the forward direction is taken as a target error value, and a target virtual sound signal corresponding to the target error value is determined. Obviously, according to the error value sorting result generated in the above manner, if the error value to be selected in the forward first order is the error value with the smallest value, the finally determined target virtual sound signal will be closest to the sound field in the central area, and may be regarded as the optimal virtual speaker signal.

Of course, for recording convenience, the finally confirmed target virtual sound signal can be recorded as

b is a value within the range of j.

Further, the respectively constructing a virtual sphere to be selected by using the distance as a radius, and mapping the position point of the preset reconstructed speaker to be a spherical point on the virtual sphere to be selected as a virtual point to be selected includes:

In particular implementations, to determine the virtual point mapped to a virtual sphere, a connection may be established between the non-center point L and a plurality of preset reconstructed speakers lspr_nReferring to fig. 3, the predetermined straight lines are dottedThe lines are shown in form. Intersecting a preset straight line with the virtual spherical surface, wherein an intersection point intersected on the virtual spherical surface is a virtual point to be selected

Due to the existence of multiple virtual spherical surfaces L_jThat is, there will be multiple sets of virtual points

For example, as a virtual sphere L₁For example, there is also a virtual sphere L that intersects₁A set of virtual points on

Virtual point

Not labeled in FIG. 3, lspr_nAnd lspo_mMarked as a filled circle.

Further, the step S10 includes:

step S101: when a sound field reconstruction instruction is received, determining non-central point position information, initial position information of a preset initial loudspeaker under a preset initial sound field, an initial sound signal output by the preset initial loudspeaker and central listening point position information according to 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, where M ═ 3, there is lspo₁、lspo₂And lspo₃There are 3 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.

Before the step S40, the non-center point based sound field reconstruction method further includes:

step S401: 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 initial sound in the frequency domainA signal.

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 which may be on a spherical surface centered on the non-center point L.

Further, the step S40 includes:

step S402: and calculating the distance between the center listening point and the non-center point as a translation distance.

It can be understood that, in order to obtain the virtual sound signal emitted by the virtual speaker at the virtual point to be selected, the position information of the virtual sound image to be selected may be determined based on the preset initial sound image position information, and then the virtual sound signal to be selected at the virtual point to be selected may be determined based on the position information of the virtual sound image to be selected.

It should be understood that the translation distance between the center listening point O and the non-center point L can be calculated, and if the center listening point O is located at the origin (0, 0, 0) of the coordinate system, the non-center point L can be recorded 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 in rectangular coordinates other than as (x)_L,y_L,z_L) In addition, the non-center point L may also be represented in polar coordinate form as

Wherein R is_LIs the distance, θ, between the non-center point L and the origin O_LRefers to the angle between the x-axis projection and the x-axis of the line connecting the non-center point L and the origin O,

refers to the angle between the line connecting the non-center point L and the origin O and the xOy plane.

Step S403: and determining virtual sound image position information to be selected corresponding to the non-central point according to the preset initial sound image position information and the translation distance under a preset sound image azimuth translation formula.

It can be understood that, in a preset virtual sound field reconstruction model, a to-be-selected virtual sound signal output at a to-be-selected virtual point is determined according to preset initial sound image position information in the preset initial sound field, where the preset virtual sound field reconstruction model includes a preset sound image azimuth translation formula and a preset virtual sound signal determination formula.

In a specific implementation, 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, the preset initial sound image position information may be recorded as Do, and the sound image position information generated by the virtual speaker at the non-center point L may be obtained by translating the Do.

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 to be selected generated by the virtual loudspeaker at the non-central point L can be determined through the sound image orientation panning formula.

Step S404: and determining the virtual sound signal to be selected at the virtual point to be selected according to the position information of the virtual sound image to be selected and the position information of the virtual point to be selected under a preset virtual sound signal determination formula.

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

wherein D is_vRepresenting the position information of the virtual sound image,

virtual point position information representing a virtual point,

while

Representing a virtual sound signal emitted by a loudspeaker at a virtual point, e.g.,

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 sound image azimuth translation formula and the preset virtual sound signal determination formula, the virtual sound signal to be selected at the virtual point is determined with 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 the virtual sound image position information D to be selected_vSo that the initial loudspeaker lspo is preset_mThe sound source localization experience brought about at the central listening point O will be at the virtual loudspeaker

The sound source positioning experience brought by the generated sound field at the non-central point L is similar, and 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 preset sound field reconstruction model includes a preset virtual sound pressure calculation formula and a preset reconstruction sound pressure calculation formula;

the step S60 includes:

step S601: and determining the virtual sound pressure of the target virtual sound signal at the non-central point through the preset virtual sound pressure calculation formula.

It will be appreciated that after the target virtual sound signal is acquired, the target virtual sound signal may be represented as

In addition, since there are N speakers actually present and N virtual sound signals are also present, the speakers are slave speakers respectively

To

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

Is transformed into

Are respectively slave

To

As for the preset virtual sound pressure calculation formula,

wherein,

target virtual point expressed as determined virtual sphere

The virtual speaker at (a) generates a sound pressure at a non-center point L,

for the target virtual sound signal in the time domain, L represents the position information of the non-central point,

position information of the target virtual point is shown, and c is a sound velocity.

Step S602: 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 of the virtual speaker at the non-center point at the target virtual point is obtained

The virtual sound pressure may then be realistically realized based on the reconstructed acoustic signal output by the preset reconstruction speaker. Specifically, the preset reconstruction sound pressure calculation formula is,

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

It will be understood that by combining

Is given as pr_n(L, t), i.e., g can be determined_n(t) of (d). Obviously, the to-be-output reconstructed acoustic signals corresponding to the preset reconstructed loudspeakers can be obtained by adjusting the emission time t of the reconstructed acoustic signals, and the sound field can be reconstructed at the non-central point by outputting the reconstructed acoustic signals.

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 introduction

Then the reconstructed sound pressure pr that the preset reconstructed speaker constructed at the non-center point L may 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,

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

The reconstructed sound signal to be finally output in this embodiment may reconstruct a reconstructed sound field, and the reconstructed sound field has a sound field quality at the non-central point L similar to that of the original sound field constructed by the original sound signal at the central listening point O.

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:

accordingly, the following operations are also implemented:

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 initial position information of a preset initial speaker in a preset initial sound field, where the non-central point position information is different from central listening point position information in the preset initial sound field;

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

the virtual point determining module 30 is configured to respectively construct a virtual spherical surface to be selected by using the distance as a radius, and map the position point of the preset reconstructed speaker to a spherical point on the virtual spherical surface to be selected as a virtual point to be selected;

the virtual sound signal generating module 40 is configured to determine, according to preset initial sound image position information in the preset initial sound field, a to-be-selected virtual sound signal output at the to-be-selected virtual point;

a virtual sound signal selection module 50, configured to select, in a sound pressure error selection model, a target virtual sound signal from the to-be-selected virtual sound signal according to an initial non-central area sound field, where the preset initial speaker is constructed in a preset non-central area, where the preset non-central area is a spherical area with the non-central point as a center;

a sound field reconstruction module 60, configured to determine, in a preset sound field reconstruction model, a reconstructed sound signal to be output at the preset reconstruction speaker according to the target 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 virtual sound signal selecting module 50 is further configured to determine, in the preset initial sound pressure calculation formula, an initial sound pressure in a preset non-center region according to the initial position information of the preset initial speaker, and determine an initial non-center region sound field corresponding to the initial sound pressure; determining the sound pressure of the non-central area to be selected in the preset non-central area according to the virtual point to be selected and the virtual sound signal to be selected in the preset area sound pressure calculation formula, and determining each sound field of the non-central area to be selected corresponding to the sound pressure of the non-central area to be selected; determining a corresponding error value to be selected according to the initial non-central area sound field and the non-central area sound field to be selected in the preset mean square error calculation formula; and selecting a target error value from the error values to be selected, and determining a target virtual sound signal corresponding to the target error value.

In an embodiment, the virtual point determining module 30 is further configured to construct a virtual sphere to be selected, which uses the non-central point as a sphere center and the distance as a radius; and taking an intersection point between the virtual spherical surface to be selected and a preset straight line as a virtual point to be selected, wherein the preset straight line is a straight line connecting the non-central point and the position point of the preset reconstruction loudspeaker.

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

the instruction initiating module 10 is further configured to, when a sound field reconstruction instruction is received, determine, according to the sound field reconstruction instruction, non-central point position information, initial position information of a preset initial speaker in a preset initial sound field, an initial sound signal output by the preset initial speaker, and central listening point position information, where the central listening point position information is used to represent position information of a central listening point;

and the sound image construction module is used for constructing preset initial sound image position information with the central sound 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 40 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 to be selected corresponding to the non-central point according to the preset initial sound image position information and the translation distance under a preset sound image azimuth translation formula; and determining the virtual sound signal to be selected at the virtual point to be selected according to the position information of the virtual sound image to be selected and the position information of the virtual point to be selected under a preset virtual sound signal determination formula.

In an embodiment, the sound field reconstructing module 60 is further configured to determine a virtual sound pressure of the target 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 60 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:

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

determining a reconstructed sound signal to be output at the preset reconstruction loudspeaker according to the target virtual sound signal in a 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;

the sound pressure error selection model comprises a preset initial sound pressure calculation formula, a preset area sound pressure calculation formula and a preset mean square error calculation formula;

the preset initial sound pressure calculation formula is as follows,

wherein, p (β)_x,β_y,β_z) At point β ═ (β)_x,β_y,β_z) Initial sound pressure of (β) ═ β_x,β_y,β_z) For presetting arbitrary listening points, lspo, in non-central regions_mSetting initial position information of a preset initial loudspeaker, setting S as an initial sound signal generated when the preset initial loudspeaker constructs a preset initial sound field, and setting S as a frequency domain signal;

the sound pressure calculation formula of the preset area is as follows,

in order to have a virtual point to be selected,

a virtual sound signal generated for a virtual speaker;

the preset mean square error calculation formula is as follows,

wherein E is_jIn order to have an error value to be selected,

to select a non-center region sound field, S_dIs an initial non-central area sound field;

selecting a target error value from the error values to be selected, and determining a target virtual sound signal corresponding to the target error value;

the determining, according to the preset initial sound image position information in the preset initial sound field, a virtual sound signal to be selected output at the virtual point to be selected includes:

the preset sound image azimuth translation formula is that,

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 translation distance is represented, and the position information of the virtual sound image to be selected, which is generated by the virtual loudspeaker at the non-central point L, can be determined through the sound image azimuth translation formula;

determining a virtual sound signal to be selected at the virtual point to be selected according to the virtual sound image position information to be selected and the virtual point position information of the virtual point to be selected under a preset virtual sound signal determination formula;

the preset virtual sound signal determination formula is that,

wherein D is_vRepresenting the position information of the virtual sound image,

to representVirtual point position information of the virtual point,

while

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

is lspv₂A virtual sound signal emitted by a speaker at a point;

the preset sound field reconstruction model comprises a preset virtual sound pressure calculation formula and a preset reconstruction sound pressure calculation formula;

the preset virtual sound pressure calculation formula is as follows,

wherein,

target virtual point expressed as determined virtual sphere

The virtual speaker at (a) generates a sound pressure at a non-center point L,

position information indicating a target virtual point, c represents a sound velocity;

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;

the preset reconstruction sound pressure calculation formula is as follows,

wherein, pr_n(L, t) represents the sound pressure, g, produced by the intended reconstruction speaker at the off-center point L_n(t) for the reconstructed acoustic signal to be output by the preset reconstruction loudspeaker, L indicates the position information of the non-center point, lspr_nRepresenting the position information of the preset reconstruction speaker, and c is the sound velocity.

2. The non-center point-based sound field reconstruction method according to claim 1, wherein the steps of constructing virtual spheres to be selected respectively by using the distance as a radius and mapping the position points of the preset reconstruction speakers to spherical points on the virtual spheres to be selected as virtual points to be selected comprise:

3. 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 initial position information of a preset initial speaker in a preset initial sound field according to the sound field reconstruction instruction comprises:

when a sound field reconstruction instruction is received, determining non-central point position information, initial position information of a preset initial loudspeaker under a preset initial sound field, an initial sound signal output by the preset initial loudspeaker and central listening point position information according to the sound field reconstruction instruction, wherein the central listening point position information is used for representing the position information of a central listening point.

4. The non-center-point-based sound field reconstruction method according to claim 3, 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:

5. 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 4.

6. 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 4.

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