Partition control method and equipment of sound field, medium and product

Abstract

The invention provides a sound field partition control method and device, a medium and a product, the method is applied to a target device configured with a loudspeaker array, the loudspeaker array is used for forming a sound field capable of being controlled in a partition mode in a specific physical space, and the sound field can be controlled in the partition mode by determining a bright area and a dark area in the sound field. Any control point in the listening area in the bright area is a target control point; constructing a constraint condition according to a first target sound field corresponding to the target control point, and solving a target function of the sound field to obtain a control filter vector for driving the loudspeaker array; and generating a driving signal for driving the loudspeaker array according to the control filter vector, and performing partition control on the sound field. The partition control effect of the sound field can be improved.

Description

Technical Field

[0001] This application relates to the field of audio processing, and more particularly to a method, device, medium, and product for zoning control of a sound field. Background Technology

[0002] Achieving high-quality sound field zoning control within specific acoustic spaces has become one of the key technologies for enhancing the user's audiovisual experience. For example, achieving high-quality sound field zoning control inside vehicles (such as smart cars) can improve the user's driving and riding experience.

[0003] Currently, mainstream sound field zoning control methods typically aim to maximize the sound energy ratio between bright and dark areas and minimize the sound field reconstruction error in the bright area. Weighting parameters are introduced to balance these two objectives, aiming to improve acoustic isolation between bright and dark areas while reducing sound quality distortion in the bright area. However, this approach heavily relies on manual adjustment of the weighting parameters, requiring significant time for repeated testing and optimization.

[0004] To reduce the complexity of parameter tuning, some solutions transform the bright-area sound field reconstruction error into a strong constraint objective, forcing the bright-area sound field to be strictly equal to the target sound field, with the optimization objective being solely "maximizing the sound energy ratio between the bright and dark areas." However, this strategy significantly compresses the feasible solution space, resulting in poor acoustic isolation performance. Furthermore, when the target sound field changes with the usage scenario, it produces a noticeable audio fragmentation, leading to poor control over sound field zoning. Summary of the Invention

[0005] Based on the above-mentioned technological status, this application provides a method, device, medium, and product for zoning control of sound field, which can improve the control effect of sound field zoning.

[0006] To achieve the above-mentioned technical objectives, this application proposes the following technical solution: According to a first aspect of the present application, a method for zoned control of a sound field is provided, applied to a target device configured with a loudspeaker array, the loudspeaker array being used to form a zoned controllable sound field in a specific physical space. The method includes: determining a bright area region and a dark area region in the sound field, and a target control point in the bright area region; the target control point characterizing a key listening position in the bright area region; determining a first target sound field corresponding to the target control point, and constructing constraints for zoned control of the sound field based on the first target sound field; solving an objective function corresponding to the sound field under the constraints to obtain a control filter vector for driving the loudspeaker array; generating a driving signal based on the control filter vector, and using the driving signal to drive the loudspeaker array to perform zoned control of the sound field.

[0007] In some implementations, determining the target control point in the visible area includes: obtaining the user's head position in the visible area; and determining any preset control point among the user's head positions as the target control point in the visible area.

[0008] In some implementations, the specific physical space includes the vehicle space; determining the first target sound field corresponding to the target control point includes: determining the current scene type of the vehicle space, the current scene type representing whether each seat in the vehicle space is occupied by a user, and the user's sitting posture when the user is occupied; and determining the first target sound field corresponding to the target control point under the current scene type based on the current scene type and a preset mapping relationship between the scene type and the target sound field corresponding to the control point.

[0009] In some implementations, the step of constructing the constraints for partitioned control of the sound field based on the first target sound field includes: determining the sound transfer function from the loudspeaker array to the target control point; determining the actual sound pressure vector of the target control point based on the sound transfer function and the control filter vector; and constructing the constraints for partitioned control of the sound field based on the condition that the actual sound pressure vector of the target control point is equal to the first target sound field.

[0010] In some implementations, the constraint condition includes: the actual sound pressure vector of the target control point is equal to the first target sound field.

[0011] In some implementations, the objective function is used to solve for a control filter vector that minimizes the weighted sum of the reconstruction error of the bright area and the acoustic energy of the dark area. The objective function is constructed using the following steps: determining the second target sound field corresponding to the bright area; determining the actual sound field of the bright area based on the sound transfer function matrix of the bright area and the control filter vector; constructing the reconstruction error of the bright area based on the difference between the actual sound field of the bright area and the second target sound field; constructing the acoustic energy of the dark area based on the sound transfer function matrix of the dark area and the control filter vector; and constructing the objective function based on the reconstruction error of the bright area, the acoustic energy of the dark area, and their respective weight parameters.

[0012] In some implementations, the specific physical space includes an in-vehicle space; determining the second target sound field corresponding to the bright area includes: determining the current scene type of the in-vehicle space, the current scene type representing whether each seat in the in-vehicle space is occupied by a user, and the user's sitting posture when the user is occupied; and determining the second target sound field corresponding to the bright area under the current scene type based on the current scene type and a preset mapping relationship between the scene type and the target sound field corresponding to the bright area.

[0013] According to a second aspect of the present application, an electronic device is provided, including a memory and a processor; the memory is connected to the processor and is used to store a program; the processor is used to implement the sound field partitioning control method as described in the first aspect by running the program in the memory.

[0014] According to a third aspect of the embodiments of this application, a storage medium is provided, on which a computer program is stored, and when the computer program is run by a processor, it implements the sound field partitioning control method as described in the first aspect.

[0015] According to a fourth aspect of the embodiments of this application, a computer program product is provided, including computer program instructions that, when executed by a processor, cause the processor to perform: a sound field partitioning control method as described in the first aspect.

[0016] This application provides a method, device, medium, and product for zoned control of a sound field, applied to a target device equipped with a loudspeaker array. The loudspeaker array is used to form a zoned and controllable sound field in a specific physical space. The method involves determining a bright area, a dark area, and a target control point within the bright area. The target control point is any control point within the listening area of ​​the bright area. A first target sound field corresponding to the target control point is determined, and constraints for zoned control of the sound field are constructed based on the first target sound field. Under these constraints, an objective function corresponding to the sound field is solved to obtain a control filter vector for driving the loudspeaker array. A driving signal is generated based on the control filter vector, and the loudspeaker array is driven using the driving signal to achieve zoned control of the sound field. Because constraints are constructed for the target control point in the bright area during the objective function optimization process, compared to traditional ACC-PM methods that rely on weighted adjustments, there is no need to further adjust this term, thus avoiding a large amount of trial-and-error parameter tuning based on experience and significantly reducing the complexity of system parameter tuning. Furthermore, it can ensure a balanced control of sound quality and isolation in the low frequencies without sacrificing the degrees of freedom in the resolution space, and avoid any abrupt changes or disjointedness in the listening experience when the target sound field switches scenes in the high frequencies, thus ensuring the continuity of the listening experience. Therefore, it can improve the zonal control effect of the sound field. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this application. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0018] Figure 1 A flowchart illustrating a sound field zoning control method provided in this application embodiment.

[0019] Figure 2 This is a schematic diagram of the structure of a sound field zoning control device provided in an embodiment of this application.

[0020] Figure 3 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Detailed Implementation

[0021] The technical solutions provided in this application can be applied, by way of example, to hardware devices such as processors, electronic devices, and servers (including cloud servers), or packaged as software programs and run. When the hardware device executes the processing procedure of the technical solutions in this application, or when the aforementioned software program is run, the target task can be automatically split and the application programming interfaces required by the task can be automatically invoked to achieve the purpose of the target task. This application only provides illustrative descriptions of the specific processing procedure of the technical solutions in this application and does not limit the specific implementation form of the technical solutions in this application. Any technical implementation form that can execute the processing procedure of the technical solutions in this application can be adopted by this application.

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0023] Before introducing the solution proposed in this application, the relevant technologies will first be introduced: As transportation gradually transforms into "intelligent mobile spaces," the cockpit is no longer merely a driving platform, but has evolved into a multifunctional space integrating travel, entertainment, and work. Under this trend, the audio system it carries has also upgraded from a traditional "single playback tool" to the "core of contextualized acoustic services," and sound field zoning control technology, as a key enabling technology supporting this upgrade, is becoming increasingly important.

[0024] Taking automobiles as an example, the so-called vehicle sound field zoning control refers to the use of acoustic signal processing algorithms and multi-channel speaker arrays to divide the physical space inside the vehicle into multiple independent acoustic zones (including bright zones and dark zones). Each bright zone can play audio content independently and supports personalized volume adjustment and sound effect settings. At the same time, it effectively suppresses sound leakage to other areas (dark zones), thereby ensuring that the audio experience of users in different seats does not interfere with each other and meets the differentiated auditory needs of drivers and passengers in diverse scenarios.

[0025] In terms of application scenarios, in-vehicle sound field zoning technology has covered a variety of travel scenarios: In family travel scenarios, the driver in the front row needs to clearly receive navigation instructions and driving assistance prompts, while the rear children's area can play animated audio, avoiding auditory confusion caused by the traditional all-area playback mode; In business travel scenarios, the driver and passenger can conduct separate conference calls or access voice files to ensure the privacy of their communication. During long-distance driving or rest, you can also set exclusive sleep-inducing white noise, natural sound effects or light music for different seats, which can significantly improve the comfort of driving and riding.

[0026] In the multimodal interaction system of the smart cockpit, sound field zoning technology can also be linked with the voice assistant to achieve "directional voice feedback," which only provides feedback in the seat area where the voice command is initiated, avoiding disturbing other passengers and further optimizing the human-computer interaction experience.

[0027] At the same time, users' requirements for in-car sound quality have upgraded from "being able to hear clearly" to "sounding well," which is specifically reflected in three dimensions: 1. Increased requirements for audio fidelity: Not only do we pursue clear vocals and accurate instrument reproduction, but we also pay attention to the spatial positioning of stereo sound, the fullness of low frequencies and the delicacy of high frequencies. 2. Increased demand for personalized acoustic environments: Expectations to dynamically adjust acoustic parameters based on seating position, personal preferences, and even real-time states (such as relaxation or focused work). 3. Reduced tolerance for acoustic interference; even slight crosstalk (such as navigation sounds infiltrating the rear music area) can significantly disrupt the immersive experience and user experience.

[0028] In the current automotive sound field zoning technology system, algorithm research focusing on single sound source isolation and regionalized playback is the core direction. Among them, the Acoustic Contrast Control (ACC), Sound Pressure Matching (PM), and their fusion improvement scheme ACC-PM algorithm are the most typical, as detailed below: At the basic algorithm level, Acoustic Contrast Control (ACC) aims to maximize the sound energy ratio between bright and dark areas. By adjusting the speaker output signal, it enhances the sound energy in the target area (bright area) while suppressing the sound energy in non-target areas (dark areas), thus achieving audio isolation between regions. This algorithm is simple in principle and can quickly build basic zone effects in single-source scenarios. However, its suppression accuracy in dark areas is limited, and it is prone to crosstalk problems in complex acoustic environments (such as seat reflections or confined spaces), making it difficult to meet high isolation requirements. Sound pressure matching (PM) focuses on minimizing the reconstruction error in bright areas. It calculates the optimal filter parameters by pre-measuring the sound transfer function from the loudspeaker to a reference point in the bright area, making the actual sound field in the bright area as close as possible to the preset target sound field. Compared to AAC, PM performs better in terms of sound quality fidelity in bright areas, effectively reducing audio distortion introduced by sound energy adjustment. However, this algorithm does not explicitly constrain the sound energy in dark areas, and its isolation effect relies on the natural diffusion and attenuation of the sound field in the bright area, resulting in weaker isolation in scenarios with concurrent sound generation from multiple areas.

[0029] To balance isolation and sound quality, the improved ACC-PM algorithm was developed. This algorithm integrates the core objectives of ACC and PM, balancing the "sound energy ratio between bright and dark areas" and "sound reconstruction error in the bright area" by introducing weight parameters. This improves acoustic isolation while reducing sound quality distortion in the bright area. Its general objective function coordinates the relationship between the bright area transfer function, the dark area transfer function, and the target sound field through weight parameters, achieving an optimized balance between the two objectives. This has made it the mainstream algorithm choice for single-source sound zoning scenarios.

[0030] However, sound field zoning schemes, represented by ACC-PM and its variants, have significant limitations: First, since there is no clear mapping relationship between the weight parameters and the actual sound field zoning control effect (i.e., isolation improvement and sound quality distortion), their values ​​are highly dependent on empirical parameter tuning. Furthermore, different parameters are required for different vehicle platforms in different frequency bands, resulting in a large workload for parameter tuning.

[0031] Secondly, to simplify the parameter tuning process, some solutions attempt to transform the bright-area sound field reconstruction error into a strong equality constraint, that is, to force the bright-area sound field to be strictly equal to the target sound field, and to use "maximizing the sound energy ratio between the bright and dark areas" as the optimization objective. Although this method reduces the workload of parameter tuning, it significantly compresses the feasible solution space of the optimization problem, severely sacrifices the system's degrees of freedom, and results in a significant loss of isolation performance.

[0032] More importantly, when the target sound field dynamically switches with the usage scenario (such as switching from navigation voice to stereo music), the constraints must also switch accordingly. This can lead to sudden changes in the listening experience in the bright area and fluctuations in isolation, resulting in a noticeable audio disconnect when switching scenarios and poor overall sound field zoning control.

[0033] In view of this, the embodiments of this application aim to provide a method, device, medium, and product for zoned control of sound field. This method selects a single control point within the user's listening area in the bright zone and imposes strong constraints on its sound field reconstruction error. In the overall ACC-PM objective function, minimizing the reconstruction error of the remaining control points and sound quality is used as a joint optimization objective. On the one hand, since only a single control point is strongly constrained, sufficient degrees of freedom in the solution space can still be retained. On the other hand, in the low-frequency band (longer wavelength, stronger spatial coherence), this single-point constraint can effectively drive the sound field fidelity of adjacent areas, thereby achieving a good balance between sound quality reproduction and dark zone isolation. In the high-frequency band or in scenarios with dynamic switching of the target sound field, the spatial influence range of the single-point constraint is significantly reduced due to the shortened wavelength, and the optimization process naturally tilts towards minimizing the sound energy in the dark zone, thereby ensuring a smooth transition and continuity in the listening experience of the bright zone. These will be described in detail in the following embodiments.

[0034] Exemplary methods Figure 1 This is a flowchart illustrating a sound field zoning control method provided in an embodiment of this application. Figure 1 As shown, the sound field zoning control method provided in this embodiment can be applied to a target device configured with a loudspeaker array. The loudspeaker array is used to form a zoned and controllable sound field in a specific physical space. The method includes the following steps S101-S104: S101. Determine the bright area and dark area in the sound field, as well as the target control point in the bright area; the target control point is any control point within the listening area of ​​the bright area.

[0035] In this embodiment, the target device can be a vehicle (such as a smart car or an autonomous taxi), an airplane cabin, a high-speed train carriage, or other means of transportation with enclosed or semi-enclosed interior spaces, or it can be an audio control device. This audio control device can be deployed in various acoustically confined environments, such as enclosed or semi-enclosed areas like train carriages, concert halls, conference rooms, and multi-functional meeting rooms.

[0036] Accordingly, a specific physical space can be the acoustic environment area inside the target equipment where passengers can sit or stay (such as a cabin or passenger compartment), or it can be a closed or semi-closed space located outside the target equipment but covered by its acoustic regulation (such as the aforementioned carriage, concert hall, or meeting room). For ease of understanding, the following will use the vehicle space as an example: A sound field refers to the spatial region in which sound waves propagate and form a perceptible sound pressure distribution within a medium (such as air). The bright area is the region within this physical space where the target audio content is expected to be produced; that is, the location where the user needs to hear the sound clearly. The dark area, on the other hand, is the region where the target audio content is suppressed or eliminated as much as possible to avoid sound interference or protect privacy. The division of bright and dark areas can be dynamically adjusted according to the actual application scenario. They do not overlap spatially, and their location, number, and range can be flexibly set, not limited to fixed seats or preset areas.

[0037] Taking business travel scenarios as an example, if the driver and passenger need to conduct independent conference calls or review voice files, the driver and passenger areas can be set as two separate bright areas, while the rear seat area can be set as a dark area, thereby achieving private audio interaction between the two people in the front row and avoiding sound interference to the rear passengers.

[0038] The target control point is any control point within the user's hearing area in the bright area. The hearing area can be the area where the user's head is located, or the area around the user's ears. In some embodiments, determining the target control point in the bright area includes: obtaining the position of the user's head area in the bright area, and determining any preset control point within the user's head area as the target control point in the bright area. For example, the head centroid and the projection point of the nose tip can be used as target control points.

[0039] In other embodiments, determining the target control point in the illuminated area includes: acquiring the location of the user's ear region in the illuminated area, and determining any preset control point within the user's ear region location as the target control point in the illuminated area. For example, the center of the ear canal entrance and the auricle reference point can be used as target control points.

[0040] Taking intelligent vehicles as an example, the location of a user's head and ears can be obtained through visual sensors installed inside the vehicle. Specifically, these visual sensors (such as infrared cameras, depth cameras, or RGB cameras) can collect facial images or 3D point cloud data of the user in the cabin, and perform target detection and key point localization on the user image using a pre-trained head region recognition model or ear key point detection model (such as architectures based on convolutional neural networks like YOLO, HRNet, or MediaPipe), thereby accurately outputting spatial information such as head pose and ear coordinates.

[0041] S102. Determine the first target sound field corresponding to the target control point, and construct the constraint conditions for partitioning the sound field based on the first target sound field.

[0042] When the specific physical space is a vehicle-mounted space, the first target sound field corresponding to the target control point is determined, including the following steps a1-a2: Step a1: Determine the current scene type of the vehicle space. The current scene type indicates whether each seat in the vehicle space is occupied by a user, and the user's sitting posture when the user is occupied.

[0043] The current scenario type can be determined based on multimodal sensor data within the target device. Taking a smart car as an example, pressure sensors installed on the seats can collect seat cushion pressure distribution data to determine whether there are occupants in each seat, or image sensors deployed in the cabin can collect visual images of the cabin area and identify whether a user is sitting in each seat based on human detection algorithms.

[0044] Furthermore, the user's sitting posture can be determined by collecting parameters such as the backrest tilt angle and seat cushion pitch angle from the seat angle sensor, or by using human posture estimation algorithms (such as OpenPose, HRNet, etc.) based on the visual images of the cabin area collected by the image sensor to locate key points of the user's torso, head and limbs, thereby accurately identifying their current sitting posture.

[0045] Step a2: Based on the current scene type and the preset mapping relationship between the scene type and the target sound field corresponding to the control point, determine the first target sound field corresponding to the target control point under the current scene type.

[0046] The target sound field corresponding to the control point refers to the expected frequency domain sound pressure vector at the control point within the bright area, which is used to characterize the ideal audio response that the user should receive at that location under a specific usage scenario.

[0047] This mapping relationship can be constructed in the following ways: for different scene types, perform acoustic simulation (such as based on boundary element method or ray tracing) at the control point location in the bright area, calibrate the sound field of the actual vehicle (measure the actual sound pressure response through microphone array), or conduct listening tests (invite users to evaluate the listening experience under different sound source layouts) to determine the target sound field that best meets the listening requirements for each scene type.

[0048] The primary target sound field can be obtained by setting a series of audio tuning-related acoustic parameters to ensure that the user has a good listening experience at that location. These parameters include: frequency response balance, low-frequency fullness and extension, mid-high frequency clarity and detail, dynamic range and distortion control, sound image positioning and spatial sense, etc.

[0049] Among them, frequency response uniformity is characterized by the fact that within the audible frequency range (20 Hz – 20 kHz), the sound pressure level should conform to the preset listening curve (such as the Harman curve, ITU-R BS.1116 standard, or brand-customized tuning style) to avoid excessive prominence or attenuation of certain frequency bands, thereby ensuring clear vocals and natural instrument reproduction.

[0050] Low-frequency fullness and extension capability indicate that there is enough energy support in the low-frequency range (usually 60–250 Hz) to bring out the sense of rhythm and atmosphere; for ultra-low frequencies (<60 Hz), the extension depth is reasonably set according to the physical capabilities of the speaker to avoid distortion or hollowness.

[0051] Clarity and detail in the mid and high frequencies indicate that the mid-frequency range (300 Hz – 2 kHz) needs to accurately reproduce the voice and main instruments, while the high-frequency range (2–20 kHz) should be delicate and extended without being harsh, ensuring a sense of space, airiness and presence. Dynamic range and distortion control characterize the ability to maintain a good linear response at different volumes, with total harmonic distortion (THD) and intermodulation distortion (IMD) controlled within acceptable thresholds to avoid distortion, compression, or blurriness. Sound image localization and spatial sense (if applicable) characterize the target sound field for stereo or multi-channel content. This can further include spatial audio parameters such as the direction, width, and sense of envelopment of virtual sound sources to create an immersive listening experience.

[0052] The relationship between the obtained scene type and the corresponding target sound field is stored in the storage unit of the vehicle system, forming a callable acoustic strategy database.

[0053] During runtime, the corresponding first target sound field can be retrieved from the mapping relationship based on the real-time identified current scene type, and then used by the subsequent sound field zoning control algorithm.

[0054] For example, in the scenario of "single driver, sitting upright", the first target sound field can be configured to simulate a mono navigation voice coming from directly in front of the dashboard to ensure clear instructions and precise positioning; while in the scenario of "single driver, half-lying down and resting", the first target sound field can be adjusted to surround white noise with spatial diffusion characteristics to create an immersive and relaxing acoustic atmosphere.

[0055] After determining the first target sound field, constraints for partitioning and controlling the sound field can be constructed based on the first target sound field. The constraints include: the actual sound pressure vector of the target control point is equal to the first target sound field.

[0056] This constraint is designed to force the actual sound pressure vector at the target control point to be constant equal to the desired first target sound field, thereby ensuring audio fidelity.

[0057] The process of determining the constraint conditions includes: determining the sound transfer function from the loudspeaker array to the target control point; determining the actual sound pressure vector of the target control point based on the sound transfer function and the control filter vector; and constructing the constraint conditions for partitioned control of the sound field based on the condition that the actual sound pressure vector of the target control point is equal to that of the first target sound field.

[0058] The sound transfer function, denoted Z1, characterizes the frequency-domain acoustic propagation characteristics from all loudspeaker units (assuming L units) in the loudspeaker array to the target control point. Each element describes the complex sound pressure response of the l-th loudspeaker unit at frequency f to the target control point, including amplitude attenuation and phase delay. This transfer function can be obtained as follows: In some implementations, a measuring microphone can be precisely placed at the target control point (such as the left ear coordinate of the driver) inside the target device (such as a smart car) to sequentially excite each speaker and record its impulse response. The frequency domain transfer function can then be obtained through Fourier transform.

[0059] In other implementations, the transfer function can be simulated and calculated based on the three-dimensional geometric model of the cockpit and the acoustic parameters of the materials (such as sound absorption coefficient and reflectivity) using the boundary element method (BEM), finite element method (FEM), or geometric acoustic methods (such as ray tracing).

[0060] Here, the control filter vector is denoted as q, representing the frequency domain drive filter coefficients applied to each channel of the loudspeaker array. Its function is to pre-filter the original audio signal, so that the desired sound field distribution is formed in space after the multi-louds cooperatively radiate. In the frequency domain, the actual sound pressure at the target control point can be expressed as the inner product of the two: Z1q.

[0061] By making the actual sound pressure vector at the target control point equal to the sound pressure vector of the target sound field, the sound pressure equality constraint condition can be constructed as shown in the following formula (1): Z1q = D1; (1) In the formula, Z1 is the sound transfer function from the loudspeaker array to the target control point; q is the control filter vector; and D1 is the first target sound field of the target control point.

[0062] S103. Under the constraints, the objective function corresponding to the sound field is solved to obtain the control filter vector used to drive the loudspeaker array.

[0063] In this embodiment, the objective function is used to solve for the control filter vector that minimizes the weighted sum of the reconstruction error in the bright area and the acoustic energy in the dark area. The objective function is constructed using the following steps b1-b4: Step b1: Determine the second target sound field corresponding to the bright area.

[0064] Here, the second target sound field corresponding to the bright area refers to the expected frequency domain sound pressure vector at control points other than the target control point in the bright area, used to characterize the ideal audio response that should be received at these locations under the current scene type. This second target sound field will serve as a reference benchmark for the bright area reconstruction error term and participate in the subsequent construction of the objective function. Specifically, step b1 includes the following steps b11 and b12: Step b11: Determine the current scene type of the vehicle space. The current scene type indicates whether each seat in the vehicle space is occupied by a user, and the user's sitting posture when the user is occupied.

[0065] The current scenario type can be determined based on multimodal sensor data within the target device. Taking a smart car as an example, pressure sensors installed on the seats can collect seat cushion pressure distribution data to determine whether there are occupants in each seat, or image sensors deployed in the cabin can collect visual images of the cabin area and identify whether a user is sitting in each seat based on human detection algorithms.

[0066] Furthermore, the user's sitting posture can be determined by collecting parameters such as the backrest tilt angle and seat cushion pitch angle from the seat angle sensor, or by using human posture estimation algorithms (such as OpenPose, HRNet, etc.) based on the visual images of the cabin area collected by the image sensor to locate key points of the user's torso, head and limbs, thereby accurately identifying their current sitting posture.

[0067] Step b12: Based on the current scene type and the preset mapping relationship between the scene type and the target sound field corresponding to the bright area, determine the second target sound field corresponding to the bright area under the current scene type.

[0068] The second target sound field is a vector containing the desired sound pressure levels of M non-target control points, where each element corresponds to the ideal sound pressure response of a non-target control point in the bright area in the frequency domain. The second target sound field can be obtained by setting a series of audio tuning-related acoustic parameters to ensure a good listening experience for the user at other control point locations within the bright area. These parameters include: frequency response balance, low-frequency fullness and extension, mid-high frequency clarity and detail, dynamic range and distortion control, sound image localization and spatial perception, etc.

[0069] Therefore, this mapping relationship can be constructed in the following way: For different scene types, based on the 3D model of the cockpit, the boundary element method (BEM), finite element method (FEM) or geometric acoustic methods (such as ray tracing) are used to simulate the sound field distribution of different audio content in various scenes, thereby obtaining the mapping relationship.

[0070] Alternatively, in a real vehicle, the above mapping relationship can be obtained by placing a microphone array at at least one non-target control point in the bright area and playing a standard test signal to measure the actual sound pressure response.

[0071] Using the above method, a set of second target sound fields that best match the auditory experience can be determined for each scene type, and the relationship between "scene type → second target sound field" can be stored in the storage unit of the vehicle system to form an acoustic strategy database that can be dynamically called.

[0072] During runtime, the controller retrieves the corresponding second target sound field from the database based on the real-time identified current scene type, and uses it to construct the bright area reconstruction error term, thereby participating in the optimization and solution of the overall sound field zoning control algorithm.

[0073] Step b2: Determine the actual sound field of the bright area to be calculated based on the sound transfer function matrix and control filter vector of the bright area, and construct the reconstruction error of the bright area based on the difference between the actual sound field of the bright area and the second target sound field.

[0074] The reconstruction error of the bright area can be expressed as: Z b qD;Z b Let be the sound transfer function matrix of the bright area, q be the control filter vector, and their inner product represent the actual sound field of the bright area. D is the second target sound field.

[0075] Step b3: Construct the acoustic energy of the dark region based on the sound transfer function matrix and control filter vector of the dark region.

[0076] The acoustic energy in the dark region can be represented by the acoustic transfer function matrix Z of the dark region. d The inner product of the control filter vector q.

[0077] Step b4: Based on the reconstruction error of the bright area, the acoustic energy of the dark area, and their respective weight parameters, construct the objective function.

[0078] The objective function can be expressed as follows: (2) (2) After constructing the objective function and its constraints, the objective function can be minimized under the constraints to obtain the control filter vector q to be solved.

[0079] In the aforementioned objective function, by imposing strong constraints on individual target control points, the sound field reconstruction error of each target control point is made zero, forcing its actual sound field to be constant equal to the first target sound field. Thus, in the low-frequency range, due to the longer wavelength of sound waves, the sound field changes slowly in space, exhibiting strong spatial coherence. At this point, precisely controlling the sound pressure of a single target control point can effectively constrain the sound field distribution in its surrounding neighborhood. Therefore, even with strong constraints on only a single control point, the overall sound quality fidelity in the bright area can be guaranteed. Simultaneously, since the reconstruction error of the control points in the bright area still participates in the minimization of the objective function as an optimization term, sufficient degrees of freedom in the solution space are preserved for optimizing the sound quality of the remaining control points in the bright area and suppressing sound energy in the dark area, achieving a balanced control of sound quality and isolation.

[0080] In the high-frequency range, as the wavelength becomes shorter, the spatial variation of the sound field becomes greater, and the area that the target control point can influence becomes smaller. At this time, the effect of the first term in the objective function (bright area reconstruction error) on the overall sound field naturally weakens, and the optimization objective will shift towards the second term (dark area sound energy suppression), prioritizing acoustic isolation performance. More importantly, since the strong constraint of the target control point at high frequencies has a limited global impact, when the target sound field changes with the scene, the constraint of the first term in the formula for sound quality optimization is relatively weak. Therefore, it is possible to avoid abrupt changes or disjointed listening experiences, ensuring the continuity of the listening experience.

[0081] Furthermore, since only a single target control point is strongly constrained, it is equivalent to performing a lossless projection along a specific direction in the solution space of the traditional weighted optimization (reconstruction error + dark area energy): there is always a scaling factor (which can be regarded as an implicit weight) that makes the actual sound pressure of the target control point equal to the first target sound field after adjustment, while this operation has minimal impact on the relative sound pressure distribution of other control points. Therefore, this strong constraint does not compress the feasible solution space and still retains sufficient degrees of freedom to optimize the overall performance. By deriving formula (2), it can be seen that the general solution that satisfies the constraint condition is a deterministic solution that can be represented by the bright and dark area transfer function and the target sound field. Therefore, as the state inside the vehicle changes, the second target sound field can adapt to change, and the control filter can also track the change in real time, i.e., q∝f(Z b Z d D).

[0082] Furthermore, since there is no need to manually adjust the explicit weight parameters between reconstruction error and dark area suppression, the complexity of algorithm parameter tuning is greatly reduced, and the deployment efficiency and robustness of the system under different vehicle models and scenarios are improved.

[0083] In summary, this application can reduce the workload of parameter tuning, ensure a balanced control of sound quality and isolation at low frequencies without sacrificing the degrees of freedom of the solution space, and ensure that when the target sound field changes with the scene at high frequencies, there is no abrupt change or sense of separation in the listening experience, thus ensuring the continuity of the listening experience.

[0084] S104. Based on the control filter vector, generate a driving signal and use the driving signal to drive the speaker array to perform zoned control of the sound field.

[0085] Specifically, after obtaining the optimal control filter vector q in the frequency domain, it is weighted with the original audio signal to be played in the frequency domain on a frequency-by-frequency basis to obtain the frequency domain drive signal of each speaker channel. Subsequently, the frequency domain drive signal is converted back to the time domain by time-frequency synthesis techniques such as inverse fast Fourier transform (IFFT) or overlap-add to generate the corresponding multi-channel time domain drive signal.

[0086] The multi-channel drive signal is amplified and impedance matched by the vehicle-mounted audio power amplifier before being output to each physical speaker unit in the speaker array. Each speaker synchronously plays pre-filtered audio content, and the sound waves coherently superimpose within the cabin space, ultimately forming a reconstructed sound field close to the target sound field in the bright areas, while achieving significant sound energy suppression in the dark areas, thus completing the zonal control of the sound field.

[0087] Exemplary device Corresponding to the above-mentioned sound field zoning control method, this application embodiment also provides a sound field zoning control device. Figure 2 This is a schematic diagram of the structure of a sound field zoning control device provided in an embodiment of this application. Figure 2 As shown, the sound field partitioning control device provided in this application embodiment is applied to a target device configured with a loudspeaker array. The loudspeaker array is used to form a partitioned and controllable sound field in a specific physical space. The device includes: a determining unit 201, a constructing unit 202, a solving unit 203, and a controlling unit 204. The determining unit 201 is used to determine the bright area region, the dark area region, and the target control point in the bright area region of the sound field. The target control point is any control point within the listening area of ​​the bright area region. The constructing unit 202 is used to determine the first target sound field corresponding to the target control point and construct constraints for partitioning the sound field based on the first target sound field. The solving unit 203 is used to solve the objective function corresponding to the sound field under the constraints to obtain a control filter vector for driving the loudspeaker array. The controlling unit 204 is used to generate a driving signal based on the control filter vector and use the driving signal to drive the loudspeaker array to perform partitioned control of the sound field.

[0088] In some embodiments, the determining unit 201 determines the target control point in the bright area, including: obtaining the head position of the user in the bright area; and determining any preset control point among the user's head positions as the target control point in the bright area.

[0089] In some embodiments, the specific physical space includes an in-vehicle space; the construction unit 202 determines the first target sound field corresponding to the target control point, including: determining the current scene type of the in-vehicle space, the current scene type representing whether each seat in the in-vehicle space is occupied by a user, and the user's sitting posture when the user is occupied; and determining the first target sound field corresponding to the target control point under the current scene type according to the current scene type and the preset mapping relationship between the scene type and the target sound field corresponding to the control point.

[0090] In some embodiments, the construction unit 202 constructs constraints for partitioned control of the sound field based on the first target sound field, including: determining the sound transfer function from the loudspeaker array to the target control point; determining the actual sound pressure vector of the target control point based on the sound transfer function and the control filter vector; and constructing constraints for partitioned control of the sound field based on the condition that the actual sound pressure vector of the target control point is equal to the first target sound field.

[0091] In some embodiments, the constraint condition includes: the actual sound pressure vector of the target control point is equal to the first target sound field.

[0092] In some embodiments, the objective function is used to solve for a control filter vector that minimizes the weighted sum of the reconstruction error of the bright area and the acoustic energy of the dark area. The objective function is constructed using the following steps: determining the second target sound field corresponding to the bright area; determining the actual sound field of the bright area based on the sound transfer function matrix of the bright area and the control filter vector; constructing the reconstruction error of the bright area based on the difference between the actual sound field of the bright area and the second target sound field; constructing the acoustic energy of the dark area based on the sound transfer function matrix of the dark area and the control filter vector; and constructing the objective function based on the reconstruction error of the bright area, the acoustic energy of the dark area, and their respective weight parameters.

[0093] In some embodiments, the specific physical space includes an in-vehicle space; determining the second target sound field corresponding to the bright area includes: determining the current scene type of the in-vehicle space, the current scene type representing whether each seat in the in-vehicle space is occupied by a user, and the user's sitting posture when the user is occupied; and determining the second target sound field corresponding to the bright area under the current scene type based on the current scene type and a preset mapping relationship between the scene type and the target sound field corresponding to the bright area.

[0094] The sound field zoning control device provided in this embodiment belongs to the same concept as the sound field zoning control method provided in the above embodiments of this application. It can execute the sound field zoning control method provided in any of the above embodiments of this application and has the corresponding functional modules and beneficial effects for executing the sound field zoning control method. Technical details not described in detail in this embodiment can be found in the specific processing content of the sound field zoning control method provided in the above embodiments of this application, and will not be repeated here.

[0095] The functions implemented by the determining unit 201, the constructing unit 202, the solving unit 203, and the control unit 204 can be implemented by the same or different processors, and this application embodiment does not limit them.

[0096] It should be understood that the units in the above device can be implemented by a processor calling software. For example, the device includes a processor connected to a memory containing instructions. The processor calls the instructions stored in the memory to implement any of the above methods or to implement the functions of each unit in the device. The processor can be a general-purpose processor, such as a CPU or microprocessor, and the memory can be internal or external to the device. Alternatively, the units in the device can be implemented as hardware circuits. By designing the hardware circuits, some or all of the unit functions can be implemented. The hardware circuits can be understood as one or more processors. For example, in one implementation, the hardware circuit is an ASIC, and the functions of some or all of the above units are implemented by designing the logical relationships between the components within the circuit. In another implementation, the hardware circuit can be implemented using a PLD, such as an FPGA, which can include a large number of logic gates. The connection relationships between the logic gates are configured through configuration files to implement the functions of some or all of the above units. All units in the above device can be implemented entirely by a processor calling software, entirely by hardware circuits, or partially by a processor calling software with the remaining parts implemented by hardware circuits.

[0097] In this application embodiment, a processor is a circuit with signal processing capabilities. In one implementation, the processor can be a circuit with instruction reading and execution capabilities, such as a CPU, microprocessor, GPU, or DSP. In another implementation, the processor can implement certain functions through the logical relationships of hardware circuits. These logical relationships are fixed or reconfigurable. For example, the processor may be a hardware circuit implemented as an ASIC or PLD, such as an FPGA. In a reconfigurable hardware circuit, the process of the processor loading a configuration document and configuring the hardware circuit can be understood as the processor loading instructions to implement the functions of some or all of the above units. Furthermore, it can also be a hardware circuit designed for artificial intelligence, which can be understood as an ASIC, such as an NPU, TPU, or DPU.

[0098] As can be seen, each unit in the above device can be one or more processors (or processing circuits) configured to implement the above methods, such as: CPU, GPU, NPU, TPU, DPU, microprocessor, DSP, ASIC, FPGA, or a combination of at least two of these processor forms.

[0099] Furthermore, the units in the above devices can be integrated in whole or in part, or they can be implemented independently. In one implementation, these units are integrated together and implemented in the form of a System-on-Chip (SoC). The SoC may include at least one processor for implementing any of the above methods or implementing the functions of the units in the device. The at least one processor may be of different types, such as CPU and FPGA, CPU and artificial intelligence processor, CPU and GPU, etc.

[0100] Exemplary electronic devices This application provides an electronic device, see [link to relevant documentation] Figure 3 As shown, the electronic device includes: Memory 200 and processor 210; The memory 200 is connected to the processor 210 and is used to store programs; The processor 210 is configured to implement the sound field partitioning control method disclosed in any of the above embodiments by running the program stored in the memory 200.

[0101] Specifically, the aforementioned electronic device may also include: a bus, a communication interface 220, an input device 230, and an output device 240.

[0102] The processor 210, memory 200, communication interface 220, input device 230, and output device 240 are interconnected via a bus. Among them: A bus can include a pathway for transmitting information between various components of a computer system.

[0103] Processor 210 can be a general-purpose processor, such as a general-purpose central processing unit (CPU), a microprocessor, etc., or an application-specific integrated circuit (ASIC), or one or more integrated circuits used to control the execution of the program of the present invention. It can also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), an off-the-shelf programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0104] Processor 210 may include a main processor, as well as a baseband chip, modem, etc.

[0105] The memory 200 stores a program that executes the technical solution of this invention, and may also store an operating system and other key business functions. Specifically, the program may include program code, which includes computer operation instructions. More specifically, the memory 200 may include read-only memory (ROM), other types of static storage devices capable of storing static information and instructions, random access memory (RAM), other types of dynamic storage devices capable of storing information and instructions, disk storage, flash memory, etc.

[0106] Input device 230 may include a device for receiving user input data and information, such as a keyboard, mouse, camera, scanner, light pen, voice input device, touch screen, pedometer, or gravity sensor.

[0107] Output device 240 may include devices that allow information to be output to a user, such as a display screen, printer, speaker, etc.

[0108] The communication interface 220 may include a device that uses any transceiver to communicate with other devices or communication networks, such as Ethernet, Radio Access Network (RAN), Wireless Local Area Network (WLAN), etc.

[0109] The processor 210 executes the program stored in the memory 200 and calls other devices, which can be used to implement the various steps of any of the sound field partitioning control methods provided in the above embodiments of this application.

[0110] This application also proposes a chip including a processor and a data interface. The processor reads and runs a program stored in a memory through the data interface to execute the sound field zoning control method described in any of the above embodiments. For the specific processing procedure and its beneficial effects, please refer to the embodiments of the sound field zoning control method described above.

[0111] Exemplary computer program products and storage media In addition to the methods and devices described above, embodiments of this application may also be computer program products, which include computer program instructions that, when executed by a processor, cause the processor to perform the steps in the sound field zoning control method according to various embodiments of this application as described in any of the above embodiments of this specification.

[0112] The computer program product can be written in any combination of one or more programming languages ​​to perform the operations of the embodiments of this application. The programming languages ​​include object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can be executed entirely on the user's computing device, partially on the user's computing device, as a standalone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server.

[0113] Furthermore, embodiments of this application may also be storage media storing a computer program, which is executed by a processor of the steps in the sound field zoning control method according to various embodiments of this application described in any of the foregoing embodiments of this specification.

[0114] For the foregoing method embodiments, in order to simplify the description, they are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, because according to this application, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0115] It should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For apparatus embodiments, since they are basically similar to method embodiments, the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0116] The steps in the methods of the various embodiments of this application can be adjusted, merged, or deleted in order according to actual needs, and the technical features described in each embodiment can be replaced or combined.

[0117] The modules and sub-modules in the various embodiments of the present application's devices and terminals can be merged, divided, and deleted according to actual needs.

[0118] It should be understood that the disclosed terminals, devices, and methods can be implemented in other ways, given the several embodiments provided in this application. For example, the terminal embodiments described above are merely illustrative. For instance, the division of modules or sub-modules is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple sub-modules or modules may be combined or integrated into another module, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or modules, and may be electrical, mechanical, or other forms.

[0119] The modules or submodules described as separate components may or may not be physically separate. The components that constitute a module or submodule may or may not be physical modules or submodules; that is, they may be located in one place or distributed across multiple network modules or submodules. Some or all of the modules or submodules can be selected to achieve the purpose of this embodiment's solution, depending on actual needs.

[0120] Furthermore, the functional modules or sub-modules in the various embodiments of this application can be integrated into one processing module, or each module or sub-module can exist physically separately, or two or more modules or sub-modules can be integrated into one module. The integrated modules or sub-modules described above can be implemented in hardware or in the form of software functional modules or sub-modules.

[0121] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0122] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software unit executed by a processor, or a combination of both. The software unit can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0123] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0124] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for zoned control of a sound field, characterized in that, The method, applied to a target device configured with a loudspeaker array for forming a zone-controllable sound field in a specific physical space, includes: Identify the bright area and dark area in the sound field, and the target control point in the bright area; the target control point is any control point within the listening area of ​​the bright area. Determine the first target sound field corresponding to the target control point, and construct the constraint conditions for partitioning the sound field based on the first target sound field; Under the constraints, the objective function corresponding to the sound field is solved to obtain the control filter vector used to drive the loudspeaker array; Based on the control filter vector, a drive signal is generated, and the drive signal is used to drive the speaker array to perform zoned control of the sound field.

2. The method according to claim 1, characterized in that, Determining the target control point in the bright area includes: Obtain the user's head position in the bright area; Any preset control point in the user's head position is determined as the target control point in the bright area.

3. The method according to claim 1, characterized in that, The specific physical space includes the vehicle space; determining the first target sound field corresponding to the target control point includes: Determine the current scene type of the vehicle space, wherein the current scene type represents whether each seat in the vehicle space is occupied by a user, and the user's sitting posture when the user is occupied; Based on the current scene type and the preset mapping relationship between the scene type and the target sound field corresponding to the control point, the first target sound field corresponding to the target control point under the current scene type is determined.

4. The method according to claim 1, characterized in that, The constraint conditions for partitioning and controlling the sound field based on the first target sound field include: Determine the sound transfer function from the loudspeaker array to the target control point; The actual sound pressure vector of the target control point is determined based on the sound transfer function and the control filter vector. Based on the condition that the actual sound pressure vector of the target control point is equal to that of the first target sound field, constraints for partitioning and controlling the sound field are constructed.

5. The method according to any one of claims 1-4, characterized in that, The constraint condition includes: the actual sound pressure vector of the target control point is equal to the first target sound field.

6. The method according to any one of claims 1-4, characterized in that, The objective function is used to solve for the control filter vector that minimizes the weighted sum of the reconstruction error in the bright area and the acoustic energy in the dark area. The objective function is constructed using the following steps: Determine the second target sound field corresponding to the bright area; The actual sound field of the bright area is determined based on the sound transfer function matrix of the bright area and the control filter vector. Based on the difference between the actual sound field of the bright area and the sound field of the second target, the reconstruction error of the bright area is constructed. The acoustic energy of the dark region is constructed based on the sound transfer function matrix of the dark region and the control filter vector. The objective function is constructed based on the reconstruction error of the bright area, the acoustic energy of the dark area, and their respective weight parameters.

7. The method according to claim 6, characterized in that, The specific physical space includes the vehicle space; determining the second target sound field corresponding to the bright area includes: Determine the current scene type of the vehicle space, wherein the current scene type represents whether each seat in the vehicle space is occupied by a user, and the user's sitting posture when the user is occupied; Based on the current scene type and the preset mapping relationship between the scene type and the target sound field corresponding to the bright area, the second target sound field corresponding to the bright area under the current scene type is determined.

8. An electronic device, characterized in that, Including memory and processor; The memory is connected to the processor and is used to store programs; The processor is configured to implement the method as described in any one of claims 1 to 7 by running a program in the memory.

9. A storage medium, characterized in that, The storage medium stores a computer program, which, when executed by a processor, implements the method as described in any one of claims 1 to 7.

10. A computer program product, characterized in that, It includes computer program instructions that, when executed by a processor, cause the processor to perform the method as described in any one of claims 1 to 7.

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