A method and system for generating a normalized volume control policy

Abstract

The application relates to the fields of intelligent traffic and public broadcasting, and specifically discloses a standardized volume control strategy generation method and system, which comprises the following steps: obtaining three-dimensional space constraint information and safety early warning event information of a target sound column; calculating space compliance sound power based on the information, and generating a fusion reference acoustic target by combining early warning scenes and point information; mapping the target into a differentiated gain parameter set of a sound column capable of forming a directional sound field; finally, dynamically weighting the parameter set based on the event emergency level and time period identifier, generating and issuing a space-time event joint optimization strategy; the system comprises four functionally corresponding modules. Through intelligent fusion of digital map environment analysis, physical sound field modeling and multi-source business rules, the application realizes the leap of volume control from simple gain adjustment to three-dimensional sound field adaptation and space-time dynamic optimization, effectively solving the core problems of accurate coverage, noise disturbance and automatic execution of standardized standards.

Description

Technical Field

[0001] This invention relates to the field of intelligent transportation and public address technology, specifically to a standardized volume control strategy generation method and system. Background Technology

[0002] In areas such as road safety warnings, loudspeakers are often deployed to provide real-time voice alerts for traffic violations. Existing systems' volume control strategies have the following limitations:

[0003] First, the strategy lacks scenario-specificity, usually only providing fixed levels such as "low, medium, and high", and cannot distinguish the different needs of different scenarios such as "non-motorized vehicles running red lights" and "gas station reminders" for volume, urgency, and interference tolerance.

[0004] Secondly, the strategy lacks environmental adaptability and cannot dynamically adjust according to real-time changes in environmental noise, resulting in it being difficult to hear in noisy places and appearing abrupt in quiet places.

[0005] More fundamentally, existing technologies treat the sound column as a single point source, only adjusting the global gain, completely ignoring the propagation characteristics of sound in three-dimensional space, installation geometry, and the actual impact of reflective barriers such as buildings on the sound field. Although there are guiding documents such as standardized volume control standards, in practice, they rely heavily on manual table lookups and experience-based judgments, making it difficult to achieve standardized and precise implementation in massive and frequent broadcasts.

[0006] Therefore, there is an urgent need for a method that can deeply integrate scene semantics, physical sound field and environmental perception, and automatically generate compliant and intelligent strategies. Summary of the Invention

[0007] The purpose of this invention is to provide a standardized volume control strategy generation method and system to solve the fundamental problem in the existing road safety broadcasting system that the volume control strategy is rigid and lacks the ability to perceive and model the three-dimensional physical sound field environment, thus failing to intelligently suppress interference to the surrounding environment while ensuring effective sound coverage of the target area.

[0008] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution:

[0009] A method for generating a standardized volume control strategy includes the following steps:

[0010] S1. Obtain the scene identifier and emergency level of the safety warning event, the three-dimensional spatial constraints of the sound column, the point type, and the environmental noise data;

[0011] S2. Obtain the baseline volume by querying the standard mapping table based on scene identifier and point type, calculate the spatial compliance sound power based on three-dimensional spatial constraints, and fuse them to generate a fusion baseline acoustic target;

[0012] S3. Noise compensation correction is performed by combining the fusion reference acoustic target with environmental noise data, which is mapped to a set of differentiated gain parameters to generate an environmentally adaptive sound field strategy;

[0013] S4. Dynamically weight the set of differentiated gain parameters based on emergency level and time period to generate a spatiotemporal event joint optimization strategy and issue it.

[0014] As a preferred embodiment of the present invention, S1 specifically includes:

[0015] S11. Receive security alert event information from the video analytics platform through the message queue, and parse the predefined specific alert scenario identifier and event urgency level from its structured data fields;

[0016] S12. Based on the target device ID associated with the security warning event information, query and obtain the installation height, pitch angle, preset effective coverage sector angle, and location type information of the speaker column from the resource management database;

[0017] S13. Based on the geographic coordinates associated with the target device ID, query the digital map model, analyze whether there are acoustic reflectors within the spatial range corresponding to the preset effective coverage sector angle, generate acoustic reflection barrier existence information, and together with the aforementioned information, constitute complete three-dimensional spatial constraint information;

[0018] S14. Obtain current environmental noise data through the real-time data stream transmitted back from the target sound column or noise sensor at the same location.

[0019] As a preferred embodiment of the present invention, S13 specifically includes:

[0020] S131. Obtain the precise geographic coordinates and installation orientation angle of the target device from the resource database based on the target device ID;

[0021] S132. Taking the geographic coordinates as the center and the installation orientation angle as the starting direction, and combining the preset effective coverage sector angle, a three-dimensional sector spatial analysis area is defined in the digital map model;

[0022] S133. Call the spatial geometry analysis interface of the digital map model to query whether there are any entity models marked with predefined labels as having significant acoustic reflection characteristics within the sector-shaped spatial analysis area. The entity models include at least building facade models, large fixed billboard models, and sound barrier models.

[0023] S134. If one or more such entity models are found, it is determined that a sound reflection barrier exists, and the type, average distance relative to the sound column, and main orientation information of each model are extracted and combined to generate structured sound reflection barrier existence information; if no such model is found, empty information indicating non-existence is generated.

[0024] As a preferred embodiment of the present invention, S2 specifically includes:

[0025] S21. Using the specific warning scenario identifier and location type information as the joint input key, query the preset scenario-location volume standard mapping table and retrieve the corresponding standardized reference volume value;

[0026] S22. Based on the effective coverage sector angle and installation height in the three-dimensional spatial constraint information, calculate the actual propagation distance of the sound wave to the farthest edge of the sector; and using the actual propagation distance and the existence information of the sound reflection barrier as input, calculate the spatial compliance sound power required to meet the standard sound pressure level of the target point according to the sound wave attenuation model.

[0027] S23. A weighted fusion algorithm is used to fuse the normalized reference volume value and the spatial compliance sound power to generate a unified fusion reference acoustic target; the weighted fusion algorithm is: fusion reference acoustic target = α * normalized reference volume value + β * spatial compliance sound power, where α and β are weight coefficients preset according to the point priority.

[0028] As a preferred embodiment of the present invention, S22 specifically includes:

[0029] S221. Based on the installation height and pitch angle, calculate the actual propagation distance of the sound from the position of the sound column to the farthest ground edge point defined by the effective coverage sector angle through geometric projection relationship;

[0030] S222. Based on the location type information of the target sound column, query the volume control standardization standard, and determine the standard sound pressure level value of the corresponding location as the expected sound pressure level of the target point;

[0031] S223. Calculate the free field path loss based on the actual propagation distance according to the spherical wave attenuation model;

[0032] S224. Analyze the existence information of the sound reflection barrier, and evaluate the additional attenuation caused by the acoustic reflectors therein based on their type, average distance and orientation, and determine an environmental additional loss compensation value.

[0033] S225. Add the standard sound pressure level value, free field path loss, and environmental additional loss compensation value to calculate the spatial compliance sound power required for the column source to achieve compliance coverage.

[0034] As a preferred embodiment of the present invention, S221 specifically includes:

[0035] Establish a three-dimensional spatial coordinate system with the sound column installation point as the origin, where the Z-axis is perpendicular to the ground and pointing upwards, and the XOY plane is parallel to the ground;

[0036] Based on the installation height H and pitch angle θ, calculate the projection radius R on the XOY plane when the main axis of the sound wave is projected onto the ground. When θ > 0, the calculation formula is: R = H / tanθ; if θ ≤ 0, then set R to a preset maximum value or directly calculate the horizontal distance based on the sector.

[0037] Based on the projection radius R and the effective coverage sector angle Φ, determine the point on the ground projection profile of the outer edge of the sector that is farthest from the origin, and calculate the horizontal distance D from the origin of the farthest point on the XOY plane. horizontal ;

[0038] Based on the formula for the distance between two points in three-dimensional space, combined with the installation height H and the horizontal distance D... horizontal The actual propagation distance D of the sound from the position of the sound column to the farthest point on the ground is calculated.

[0039] As a preferred embodiment of the present invention, S224 specifically includes:

[0040] Based on the type of acoustic reflector in the acoustic reflection barrier information, query the preset acoustic material reflection loss benchmark table to obtain the benchmark reflection loss value corresponding to the material type.

[0041] Based on the average distance and orientation of the acoustic reflector, combined with the installation position of the sound column and the effective coverage sector, the proportion of acoustic shadowing area or effective reflection enhancement caused by the reflector to the target coverage area is evaluated by geometric calculation.

[0042] Based on the proportion of the acoustic shadow area or the effective reflection enhancement proportion, the reference reflection loss value is adjusted accordingly or its sign is inverted, and the environmental additional loss compensation value is finally calculated and determined; where a positive value represents a reduction in the equivalent loss after considering reflection enhancement, and a negative value represents an increase in the additional loss after considering shading.

[0043] As a preferred embodiment of the present invention, S3 specifically includes:

[0044] S31. Based on a preset noise compensation algorithm, the ambient noise data is used to dynamically correct the fusion reference acoustic target, generating a noise-corrected acoustic target; the noise compensation algorithm is: Noise-corrected acoustic target = Fusion reference acoustic target + k * (Ambient noise data - N) ref） Where k is the compensation coefficient, Nref This is a preset environmental noise reference value;

[0045] S32. Based on the hardware performance parameters of the target sound column, convert the noise-corrected acoustic target into a reference total gain value required for the sound column to achieve the noise-corrected acoustic target under rated operating conditions;

[0046] S33. Based on the effective coverage sector angle in the three-dimensional spatial constraint information, determine N horizontal directional angle partitions and obtain the directional radiation efficiency parameter corresponding to each partition;

[0047] S34. Combine the reference total gain value with the directional radiation efficiency parameter of each partition to calculate and generate an independent gain value for each partition. All N independent gain values ​​constitute the differentiated gain parameter set.

[0048] S35. Encapsulate the differentiated gain parameter set with the target sound column identifier and parameter effective time to generate the environment adaptive sound field strategy.

[0049] As a preferred embodiment of the present invention, S4 specifically includes:

[0050] S41. Based on the current system time and referring to the preset social work and rest time division rules, determine the current time period identifier, wherein the time period identifier includes at least daytime, nighttime and rest time;

[0051] S42. Using the event urgency level and time period identifier as the joint input key, query the preset dynamic weighting coefficient mapping table to obtain the corresponding dynamic weighting coefficient;

[0052] S43. Multiply the dynamic weighting coefficients by each independent gain value in the differentiated gain parameter set in the environmental adaptive sound field strategy to generate an optimized gain parameter set;

[0053] S44. Update the environmental adaptive sound field strategy with the optimized gain parameter set to generate the final spatiotemporal event joint optimization strategy;

[0054] S45. The spatiotemporal event joint optimization strategy is encoded into a control command in a specific protocol format and sent to the target speaker hardware for execution through a message middleware, thereby realizing dynamic volume enhancement or suppression based on event urgency and time period sensitivity.

[0055] A standardized volume control strategy generation system, used to implement a standardized volume control strategy generation method, includes:

[0056] The information acquisition and analysis module is used to acquire the three-dimensional spatial constraint information and safety warning event information of the target sound column; the three-dimensional spatial constraint information includes at least the installation height, pitch angle, preset effective coverage sector angle, and information on the existence of sound reflection barriers;

[0057] The fusion computing and decision-making module is used to calculate the spatial compliance acoustic power based on the three-dimensional spatial constraint information, and combine the early warning events and location information received from the information acquisition and analysis module to generate a fusion reference acoustic target.

[0058] The strategy mapping and generation module is used to map the fusion baseline acoustic target from the fusion computing and decision module into a set of differentiated gain parameters that can drive the sound column to form a directional sound field, and generate an environment-adaptive sound field strategy.

[0059] The dynamic optimization and execution module is used to dynamically weight the set of differentiated gain parameters from the strategy mapping and generation module based on the event urgency level and time period identifier, generate a spatiotemporal event joint optimization strategy, and issue it for execution.

[0060] Compared with the prior art, the present invention has the following advantages:

[0061] 1. By introducing three-dimensional spatial constraint information and using digital map models to analyze sound reflection barriers, and combining sound wave attenuation models to calculate spatial compliance sound power, a set of differentiated gain parameters that can drive hardware to shape directional sound fields is finally generated; this fundamentally solves the contradiction between accurate sound coverage and suppression of environmental interference, and realizes a leap from single volume adjustment to three-dimensional sound field adaptation.

[0062] 2. The business specification values ​​and physical model calculation values ​​are weighted and fused together, and the event urgency level and time period identifier are introduced as dual factors. The strategy is modulated through a dynamic weighted coefficient mapping table. A multi-source information fusion intelligent decision-making mechanism is constructed, which enables the strategy to simultaneously meet compliance requirements and dynamic social context needs, and achieves a balance between security effectiveness and humanistic care.

[0063] 3. By digitizing complex specification documents into built-in mapping tables and calculation logic, and establishing a fully automated decision-making chain from environmental perception to strategy generation, the inefficient and inconsistent manual judgment has been replaced, thus automating and digitizing the execution of standardized procedures. This not only significantly improves management efficiency and standardization, but also provides complete digital logs, laying the foundation for system optimization. Attached Figure Description

[0064] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0065] Figure 1 This is a flowchart illustrating the method described in Embodiment 1 of the present invention.

[0066] Figure 2 This is a framework diagram of the system described in Embodiment 2 of the present invention. Detailed Implementation

[0067] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0068] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0069] Example 1

[0070] like Figure 1 As shown, the present invention provides a standardized volume control strategy generation method, comprising the following steps:

[0071] S1. Obtain the scene identifier and emergency level of the safety warning event, the three-dimensional spatial constraints of the sound column, the location type, and the environmental noise data; specifically including:

[0072] S11. Receiving and parsing security alert event information, specifically:

[0073] The system subscribes to and receives real-time security alerts from the video analytics platform via a message queue middleware deployed on the backend. This information is transmitted in structured data messages. The system parses these messages using a protocol to extract predefined fields: a specific alert scenario identifier, such as a red-light violation warning for non-motorized vehicles or an alert at a vehicle depot entrance / exit, and an event urgency level, indicating the severity of the security event. These parsed scenario identifiers and urgency levels serve as key input parameters for subsequent policy decisions.

[0074] S12. Querying basic attribute information of the sound column, specifically:

[0075] The system accesses the resource management database based on the target device ID carried in the S11 parsing result, which is the unique identifier of the specific speaker column device that needs to perform the broadcast warning. In this database, the static configuration parameters of the speaker column device are queried through the device ID index: including the physical installation height, i.e., the vertical installation distance of the speaker column unit relative to the ground; the pitch angle, i.e., the tilt angle of the speaker's main sound axis relative to the horizontal plane; the preset effective coverage sector angle, i.e., the angle value of the designed effective sound wave coverage range of the speaker column in the horizontal direction; and the location type information of the installation point, according to the classification in the volume control standard table, such as intersection type, enterprise gate type, entrance and exit type, etc., and further subdivided into subcategories such as whether there is a residential area and whether it is open to the public.

[0076] S13. Construction of 3D Spatial Constraint Information and Identification of Sound Reflection Barriers: Based on a digital map model, the acoustic environment geometry of the physical space surrounding the sound column is analyzed. Information on the existence of sound reflection barriers is generated through spatial calculations and model retrieval. Specifically, the following sub-processes are executed:

[0077] S131. Acquisition of basic spatial parameters, specifically:

[0078] Based on the target device ID used by S12, the system re-accesses the device file record of the speaker column in the resource database to extract the precise geographic coordinates and installation orientation angle. The precise geographic coordinates are represented using a latitude and longitude coordinate system or a Cartesian coordinate system to determine the absolute position of the speaker column in physical space. The installation orientation angle is expressed using an azimuth angle, which is the clockwise rotation angle of the speaker column's main acoustic axis relative to true north or the coordinate system's reference direction on the horizontal plane, used to determine the main direction of sound wave propagation.

[0079] S132. Delineation of the sector-shaped spatial analysis region, specifically:

[0080] The system uses the precise geographic coordinates obtained in S131 as the center point and the installation orientation angle as the starting boundary direction of the sector area. Combined with the preset effective coverage sector angle obtained in S12, i.e. the central angle of the sector, a three-dimensional sector spatial analysis area is delineated in the three-dimensional urban spatial dataset constructed by the digital map model.

[0081] The area appears horizontally as a fan-shaped planar projection with a preset effective coverage sector angle as its expansion range. Vertically, based on the installation height and pitch angle parameters obtained in S12, combined with the vertical diffusion characteristics of the sound column's sound waves, it forms a three-dimensional spatial volume with a specific height range. This area covers the main physical propagation path of the sound column's sound waves radiating outward from the sound source.

[0082] S133. Acoustic reflector spatial query, specifically:

[0083] The system calls the spatial geometry analysis interface provided by the digital map model to perform entity model collision detection and attribute query within the three-dimensional sector spatial analysis area defined by S132.

[0084] The search targets are physical models marked with predefined tags as having significant acoustic reflection characteristics, specifically including three categories: building facade models, which refer to 3D models of the vertical facade of buildings with flat, hard surfaces and surface material reflectance coefficients higher than preset thresholds; large fixed billboard models, which refer to 3D models of outdoor fixed billboards constructed with metal sheets or hard composite materials and with a single-sided area exceeding preset standards; and sound barrier models, which refer to 3D models of sound barrier facilities specifically designed for traffic or industrial noise control.

[0085] The system determines whether a model falls within the analysis range by calculating the spatial intersection between the spatial bounding boxes of these entity models and the sector-shaped spatial analysis region.

[0086] S134. Sound reflection barriers generate information, specifically:

[0087] If S133 finds one or more entity models with acoustic reflection characteristics within the sector-shaped spatial analysis area, the system determines that a sound-reflecting barrier exists in the installation environment of the sound column. At this point, the system extracts the type identifier of each entity model, clearly distinguishing them into three categories: building facade, large fixed billboard, or sound barrier; relative to the average distance of the sound column, it calculates the Euclidean distance or horizontal projection distance between the geometric center point or nearest surface point of the entity model and the geographical coordinates of the sound column; and it extracts the normal direction of the reflecting surface of the entity model or the dominant direction of the model's long side based on the main orientation information; combining the above data generates structured information on the existence of sound-reflecting barriers, which stores the attribute set of each reflector in the form of a list or array.

[0088] If no matching entity model is found in S133, an empty message or a zero-length list is generated indicating that the acoustic reflection barrier does not exist.

[0089] Finally, step S13 integrates the installation height, pitch angle, preset effective coverage sector angle, and the existence information of the generated acoustic reflection barrier to form complete three-dimensional spatial constraint information, which serves as the input parameters for subsequent spatial compliance acoustic power calculation.

[0090] S14. Real-time acquisition of environmental noise data, specifically:

[0091] The system receives real-time data streams from noise sensors integrated into the target sound column or from independent noise monitoring devices located at the same or adjacent geographical coordinates. This data stream contains ambient noise sound pressure level data at the current monitoring moment, in decibels. The system performs protocol parsing and validity verification on this data stream to obtain the current ambient noise data, which serves as the dynamic input parameters for subsequent noise compensation algorithms.

[0092] S2. Obtain the baseline volume by querying the standard mapping table based on scene identifiers and point types, calculate the spatial compliance acoustic power based on three-dimensional spatial constraints, and fuse them to generate a fusion baseline acoustic target; specifically including:

[0093] S21. Normalized reference volume value decision, specifically:

[0094] S211. The system uses the specific warning scenario identifier obtained from S11 parsing and the location type information obtained from S12 querying as the joint input key to access the preset scenario-location volume specification mapping table. This mapping table is constructed according to the volume control standardization standard and stores standardized reference volume values, in decibels, for different combinations of warning scenarios and location types. The mapping logic of this mapping table is explained as follows:

[0095] a. Scene urgency correction: For high-urgency scenes, such as fighting and drunk driving, the value is increased by 0-10dB from the baseline, but not exceeding the upper limit of 90dB; for general reminder scenes, such as not wearing a helmet, the value is decreased by 5-10dB in sensitive locations in residential areas.

[0096] b. Coverage radius mapping: Strictly follow the volume gradient corresponding to the three radii of 3-5 meters, 5-8 meters, and 8-10 meters. For example, in the case of intersections without residential areas, the three levels are 50 / 60 / 90dB or 40 / 60 / 80dB, depending on the width of the intersection.

[0097] c. Special constraint marking: When the location type includes residential areas or corporate dormitories, the standardized reference volume value is automatically applied to the lower level of the corresponding category, such as the 30-50dB range, to ensure compliance with noise control regulations.

[0098] Table 1 below is an excerpt of a typical mapping example table:

[0099] Table 1: Scene-Point Volume Specification Mapping Table (Excerpt)

[0100]

[0101] S212. The system uses a joint index query mechanism to retrieve entries in the mapping table that perfectly match the current specific warning scenario identifier and location type information, and extracts the corresponding normalized reference volume value. This volume value represents a reference sound pressure level set under standard environmental conditions to meet the broadcast clarity requirements of a specific scenario and comply with noise control regulations, serving as the input for the normalized constraint formula in subsequent fusion calculations.

[0102] S22. Spatial Compliance Sound Power Calculation: Based on physical acoustic propagation theory, and combining the geometric parameters and acoustic environment characteristics in the three-dimensional spatial constraint information of the sound column, the required sound source output power to meet the standard sound pressure level requirements of the target coverage area is derived through spatial geometric calculation and acoustic attenuation modeling. The following sub-processes are specifically executed:

[0103] S221. Geometric Calculation of Actual Propagation Distance: Based on the installation height and pitch angle parameters in the three-dimensional spatial constraint information, the system accurately calculates the actual path length of the sound wave propagating from the acoustic center of the sound column to the farthest edge of the effective coverage sector through spatial geometric projection relationships; specifically:

[0104] a. Establish a three-dimensional spatial coordinate system with the sound column installation point as the origin, where the Z-axis is perpendicular to the ground and upwards, and the XOY plane is parallel to the ground;

[0105] b. Based on the installation height H, i.e., the vertical distance of the acoustic center of the column loudspeaker relative to the horizontal ground, and the pitch angle θ, i.e. the upward tilt angle of the main sound axis of the loudspeaker relative to the horizontal plane, calculate the projection radius R of the main sound axis on the XOY plane when the sound wave is projected onto the ground: When θ> 0, the calculation formula is: R = H / tanθ; if θ≤0, then set R to a preset maximum value to represent horizontal infinite propagation, or directly use the horizontal distance calculation mode based on sector geometry;

[0106] c. Based on the projection radius R and the effective coverage sector angle Φ, i.e., the central angle of the effective sound wave coverage range on the horizontal plane, determine the position of the edge point farthest from the sound column installation point on the ground projection outline of the outer edge of the sector, and calculate the horizontal distance D of this farthest edge point relative to the sound column installation point, i.e., the origin, on the XOY plane. horizontal ;

[0107] d. Based on the formula for the distance between two points in three-dimensional space, combined with the installation height H and the horizontal distance D horizontal The actual propagation distance D of sound from the acoustic center of the sound column to the farthest ground edge of the sector is calculated, i.e., D = √(H 2 + D horizontal 2 ).

[0108] S222. The standard sound pressure level at the target point is determined as follows:

[0109] Based on the location type information obtained from S12, including major categories and subcategories such as intersections, businesses, entrances / exits, rivers, and reservoirs, the system queries the standard sound pressure level requirements defined for different location types in the volume control standardization. An excerpt from the volume control standardization is shown in Table 2 below. The volume values ​​listed in the table are all measured with the front-facing speaker as the reference, corresponding to the equivalent continuous A-weighted sound level at a height of 1.2-1.5 meters above the ground. When the speaker installation involves the rear radiation area, such as two-way intersections or squares with opposing installations, the volume of the rear speaker is calculated at 50% of the volume of the front speaker to ensure compliance with noise control requirements.

[0110] Table 2: Standardized Table for Volume Control (Excerpt)

[0111]

[0112] The standard sound pressure level value represents the expected sound pressure level target value set at a specific location type to ensure that the broadcast warning content still has sufficient clarity and intelligibility at the edge of the target coverage, while meeting the environmental noise control regulations for the protection of the surrounding acoustic environment. It serves as the acoustic benchmark target for subsequent inverse calculation of sound power.

[0113] S223. Free-field path loss calculation, specifically:

[0114] The system uses the actual propagation distance calculated by S221 as the core input parameter, based on the physical model of ideal spherical wave diffusion and attenuation, to quantify the energy attenuation caused by wavefront geometric diffusion under unobstructed free field propagation conditions. This calculation is based on the principle of energy conservation in acoustic wave theory: when a point source radiates sound waves in a homogeneous isotropic medium, the sound wave energy propagates outward in the form of a spherical wave. As the propagation distance increases, the wavefront surface area expands according to the square law of distance, and the sound energy density per unit area decreases accordingly.

[0115] The specific calculation process is as follows: The system constructs a virtual spherical wavefront with the acoustic center of the loudspeaker as the sound source point and the actual propagation distance determined in S221 as the radius. According to the logarithmic law of sound pressure level attenuation with distance, the free-field path loss is equal to the logarithmic function of the propagation distance ratio multiplied by the directivity index correction coefficient. The propagation distance ratio is defined as the ratio of the actual propagation distance to the sound source reference distance, which is usually taken as 1 meter as the loudspeaker sound power calibration benchmark. The directivity index correction coefficient is based on the directivity characteristics of the loudspeaker and is corrected by the loudspeaker directivity pattern determined by the preset effective coverage sector angle and pitch angle queried in S12, to reflect the degree of sound energy concentration of the loudspeaker relative to the ideal point sound source at a specific radiation angle.

[0116] Through the above calculations, the system derives the sound pressure level attenuation caused purely by geometric diffusion during the propagation of sound waves from the sound column to the farthest edge of the effective coverage sector, i.e., the free-field path loss value. This loss value is measured in decibels and characterizes the theoretical attenuation of the sound pressure level at the target point relative to the sound pressure level at the sound column source in an ideal, non-reflective, and non-absorbent environment. It serves as a key attenuation compensation term in the S225 sound power synthesis calculation.

[0117] S224. Environmental Additional Loss Compensation Value Assessment: The system analyzes the acoustic reflection barrier existence information generated in S13. Based on the type of acoustic reflector included (building facade, large fixed billboard, or sound barrier), and the average distance and main orientation information relative to the sound column, it assesses the additional attenuation or enhancement effect of these physical entities on sound wave propagation, and determines the environmental additional loss compensation value. This compensation value characterizes the amount of correction to the equivalent propagation loss caused by the sound energy gain or attenuation due to the presence of reflectors in the actual physical environment. The specific assessment logic is as follows:

[0118] a. Based on the material type of the acoustic reflector, consult the pre-set acoustic material reflection loss benchmark table to obtain the benchmark reflection loss value corresponding to that type of entity. This benchmark value is in decibels (dB). Negative values ​​represent the potential gain capability of highly reflective surfaces, such as building exterior walls, while positive values ​​represent the inherent loss caused by sound-absorbing or sound-insulating structures, such as sound barriers. The acoustic material reflection loss benchmark table is shown in Table 3 below:

[0119] Table 3: Reference Table for Reflection Loss of Acoustic Materials

[0120]

[0121] b. Based on the average distance and main orientation of the reflector and the sound column, combined with the spatial geometric relationship between the sound column installation location and the effective coverage sector, the system performs a three-dimensional spatial analysis: calculating the incident angle and reflection angle of the reflector surface relative to the main acoustic axis of the sound column; assessing whether the reflected sound waves effectively fall within the preset effective coverage sector (i.e., effective reflection enhancement), or assessing whether the reflector blocks the direct sound path, forming an acoustic shadow area (i.e., obstruction). Through geometric projection calculations, the system quantifies the proportion of the effective reflection enhancement area to the target coverage area (i.e., the effective reflection enhancement ratio) and the proportion of the acoustic shadow area to the target coverage area (i.e., the acoustic shadow area ratio).

[0122] c. Based on the above proportions, the baseline reflection loss value is weighted and its sign is adjusted: When there is effective reflection enhancement, the environmental additional loss compensation value is calculated as the absolute value of the baseline reflection loss value multiplied by the effective reflection enhancement proportion. The result is positive, indicating compensation for free-field path loss, i.e., a reduction in equivalent loss. When there is acoustic shadowing, the environmental additional loss compensation value is calculated as the absolute value of the baseline reflection loss value multiplied by the proportion of the acoustic shadowing area, and the result is negative, indicating an increase in additional propagation loss. For complex cases where both reflection and shadowing exist simultaneously, genus superposition is performed separately to finally determine the environmental additional loss compensation value.

[0123] S225. Spatial compliant acoustic power synthesis, specifically:

[0124] The system performs an algebraic summation of the target point standard sound pressure level value (i.e., the desired sound pressure level) determined in S222, the free field path loss calculated in S223, and the environmental additional loss compensation value determined in S224.

[0125] The summation process essentially involves reverse-engineering the desired sound pressure level at the target point to the required sound pressure level at the sound source of the sound column, and then converting it into the corresponding sound power value based on the electroacoustic conversion efficiency parameter of the sound column loudspeaker, ultimately obtaining the spatial compliance sound power output required by the sound column to achieve compliant coverage.

[0126] S23. Generation of Fusion Reference Acoustic Targets: The system employs a weighted fusion algorithm to perform multi-objective optimization fusion of the normalized reference volume value obtained from the query in S21 and the spatial compliance sound power calculated in S22, generating a unified fusion reference acoustic target. This fusion process aims to balance the potential differences between regulatory constraints and physical accessibility. The specific fusion mechanism is as follows:

[0127] S231. The system determines the point priority attribute based on the point type information obtained in S12. For points located in sensitive areas, such as residential areas, schools, and company dormitories, a first weight coefficient α is set greater than a second weight coefficient β to make the fusion result more inclined towards the standardized baseline volume value, ensuring priority for regulatory compliance. For points located in open areas or main traffic arteries, such as intersections without residential areas, open squares, and elevated tunnels, a first weight coefficient α is set less than or equal to a second weight coefficient β to make the fusion result more inclined towards spatially compliant sound power, ensuring priority for physical coverage effect. The specific values ​​of the weight coefficients are preset and stored in the system configuration according to the point priority classification, such as 0.6 / 0.4, 0.5 / 0.5, or 0.4 / 0.6, etc.

[0128] S232. The system performs a weighted linear fusion calculation: Fusion baseline acoustic target = α * normalized baseline volume value + β * spatial compliance sound power. This target value is a single quantitative indicator that satisfies both the upper limit of volume constraints imposed by regulations on specific scene-location combinations and the power requirements for coverage distance based on the physical laws of acoustic propagation. It serves as the basic input parameter for the subsequent S3 environmental adaptive strategy generation stage, guiding the correction baseline of the noise compensation algorithm under dynamic environmental conditions.

[0129] S3. Noise compensation correction is performed by combining the fused baseline acoustic target with environmental noise data, mapped to a set of differentiated gain parameters, and an environmentally adaptive sound field strategy is generated; specifically including:

[0130] S31. Dynamic correction of noise compensation algorithm, specifically:

[0131] The system invokes a pre-defined noise compensation algorithm, using the fusion baseline acoustic target generated in S23 as the benchmark value, and combining it with the environmental noise data acquired in real time in S14 to perform dynamic correction calculations, generating a noise-corrected acoustic target, expressed in sound pressure level (SPL) decibels. The core logic of the noise compensation algorithm is: Noise-corrected acoustic target = Fusion baseline acoustic target + k * (Environmental noise data - N) ref） Where k is the compensation coefficient, characterizing the strength of the system's compensation for the noise masking effect, and N ref The preset environmental noise reference value is the baseline noise level in a normal quiet environment, such as 40 decibels.

[0132] When real-time ambient noise data is higher than the reference value, the algorithm automatically increases the noise-corrected acoustic target to overcome background noise interference; when ambient noise is lower than the reference value, the target is appropriately lowered to avoid overbroadcasting. Through this linear compensation relationship, the system ensures that the broadcast content still has sufficient signal-to-noise ratio and clarity under the current specific ambient noise level.

[0133] S32. Reference Total Gain Value Conversion: Based on the hardware performance parameter profile of the target speaker column, the system converts the noise-corrected acoustic target generated in S31 into the reference total gain value required for the speaker column to achieve this acoustic target under rated operating conditions. This conversion process is based on the electro-acoustic energy conversion characteristics of the speaker column system and is achieved through reverse engineering calculations. Specifically:

[0134] S321. The system retrieves the hardware performance parameters of the target speaker column from the device resource database, including at least: the sound pressure level sensitivity of the speaker unit, which characterizes the sound pressure level output capability at a specific distance under unit input power, in decibels / watts / meters; the maximum gain capability and linear operating range of the power amplifier, which characterizes the upper limit of voltage / power amplification factor and distortion-free operating range that the power amplifier circuit can provide; and the quantization accuracy and dynamic range of the digital signal processor, which characterize the step accuracy of digital gain adjustment and the noise floor level.

[0135] S322. Based on the above parameters, the system establishes an electro-acoustic conversion characteristic curve model for the speaker column. This model describes the gain transfer function from the digital audio input to the acoustic output via power amplification. Using the noise-corrected acoustic target as the desired output sound pressure level, and combining the speaker column installation height with the actual propagation distance calculated in S221, the system inversely calculates the theoretical sound pressure level that the speaker unit needs to achieve at the sound source reference point, typically at a distance of 1 meter, based on the inverse relationship between free-field sound pressure level and distance.

[0136] S323. The system converts the theoretical sound pressure level value into the electrical power value required by the speaker based on the sound pressure level sensitivity parameter of the speaker unit; then, based on the gain characteristics of the power amplifier, it reversely calculates the required electrical power into the driving voltage or power level required by the power amplifier input terminal; at the same time, the system calculates the inherent gain loss of the entire audio signal link, including line transmission loss, signal attenuation caused by long-distance cables, digital-to-analog conversion loss, quantization error and dynamic loss in the DAC conversion process, as well as non-ideal factors such as power amplifier efficiency loss and heat conversion.

[0137] S324. The system synthesizes the above reverse calculation results and determines the reference total gain value that needs to be applied at the digital gain control terminal, i.e., the digital signal processor or the front-end volume control module, in order to make the speaker output reach the acoustic target after noise correction. This gain value is expressed in decibels or as a linear digital gain coefficient, representing the amplification factor required relative to the digital audio signal reference level, and serves as the basis for the subsequent differential gain allocation in S34.

[0138] S33. Horizontal angular partitioning and directional parameter acquisition, specifically:

[0139] Based on the effective coverage sector angle obtained from the three-dimensional spatial constraint information queried in S12, i.e., the range of the central angle of effective sound wave coverage on the horizontal plane, the system divides the sector angle uniformly or non-uniformly into N horizontal directional angle partitions. For example, a 120-degree sector can be divided into three 40-degree partitions (left, center, and right), or further refined partitions can be created based on the actual road width. For each horizontal directional angle partition, the system queries the directional radiation efficiency parameter library of the target sound column to obtain the corresponding directional radiation efficiency parameter for each partition. This parameter characterizes the relative value of the sound radiation efficiency of the sound column loudspeaker array at a specific horizontal directional angle relative to the main sound axis direction, expressed in decibels. The main sound axis direction is usually 0 dB, and deviations from the main sound axis direction are negative, reflecting the beamforming characteristics and horizontal directivity pattern of the sound column.

[0140] S34. Differentiated Gain Parameter Set Calculation: The system receives the reference total gain value determined in S32 and the directional radiation efficiency parameters corresponding to each horizontal angular zone obtained in S33, performs gain allocation calculation, and generates an independent gain value for each zone. This calculation process is based on the beamforming characteristics of the column loudspeaker array, and achieves sound field homogenization control in the horizontal direction through differentiated gain allocation.

[0141] The specific calculation logic is as follows: The system iterates through the N horizontal angular partitions defined by S33, and for each partition index i (i=1,2,...,N), extracts the directional radiation efficiency parameter D corresponding to that partition. i The system uses the S32 reference total gain value G. total Based on this, according to the directional radiation efficiency parameter D i Perform reverse compensation adjustment: For partitions with high directional radiation efficiency, D i Approximately 0 dB, i.e., close to the main sound axis, with a relatively low independent gain value G. i Because this direction itself has high acoustic radiation efficiency, no additional electrical gain is needed to achieve the acoustic target; for areas with low directional radiation efficiency, D i If the value is negative, meaning it deviates from the direction of the main sound axis, then a relatively high independent gain value G needs to be allocated. i This is to compensate for the sound pressure level loss caused by directional attenuation.

[0142] In mathematics, the independent gain value G of each partition iThe independent gain value is determined through algebraic operations between the baseline total gain value and the directional radiation efficiency parameter. Specifically, the independent gain value equals the baseline total gain value minus the directional radiation efficiency parameter, or the sum of its absolute value. This ensures that, after considering the differences in radiation efficiency of each zone, the final overall acoustic output in that direction tends to be consistent and meets the acoustic target after noise correction. The system sequentially calculates the independent gain values ​​for all N horizontal directional angular zones and arranges these N independent gain values ​​in directional index order to form a differentiated gain parameter set. This set is a numerical sequence containing N elements, each element corresponding to a gain control command for a specific horizontal directional angular zone. This command guides the column digital signal processor to adjust the independent gain of the beams in each direction, achieving fine-grained control of the directional sound field.

[0143] S35. Encapsulation of environment-adaptive sound field strategy, specifically:

[0144] The system structurally encapsulates the differentiated gain parameter set generated in S34 along with the target sound column identifier and parameter effective timestamps to generate an environment-adaptive sound field strategy data package. This strategy data package includes metadata such as: the unique device identifier of the target sound column, the independent gain values ​​for each of the N horizontal angular zones, the strategy generation time, the suggested effective time, and the strategy validity period. The encapsulated environment-adaptive sound field strategy, as the final output of step S3, is passed to S4 for spatiotemporal event joint optimization processing, providing a basic strategy framework for subsequent emergency level and time-period weighted adjustments.

[0145] S4. Dynamically weight the set of differentiated gain parameters based on emergency level and time period to generate and distribute a spatiotemporal event joint optimization strategy; specifically including:

[0146] S41. Time period identification is determined, specifically:

[0147] The system obtains the current system time from the server clock or network time protocol synchronization, and determines the current time period identifier by referring to the preset social work and rest time period division rules.

[0148] This time-segmentation rule is based on the patterns of public activities and noise control regulations, dividing the day into at least three categories: daytime, typically corresponding to peak public activity periods, where higher volume broadcasting is permitted; nighttime, typically from dusk to late at night, where volume must be appropriately reduced to avoid disturbing residents; and rest periods, typically from late at night to early morning or specific periods on statutory holidays, where volume must be strictly limited. The system uses a time interval matching algorithm to map the current time to the corresponding time segment identifier, serving as the time dimension input parameter for subsequent dynamic weighted decision-making.

[0149] S42. Dynamic weighted coefficient lookup, specifically:

[0150] S421. The system extracts the event urgency level obtained from S11 and the time period identifier determined in S41 to construct a two-dimensional joint input key. The system uses this joint input key to access a preset dynamic weighting coefficient mapping table. This mapping table is constructed based on the dual constraints of public safety early warning business priority and social environmental noise sensitivity, and stores dynamic weighting coefficients corresponding to different combinations of urgency levels and time periods. The dynamic weighting coefficient mapping table is shown in Table 4 below:

[0151] Table 4: Dynamic Weighting Coefficient Mapping Table

[0152]

[0153] S422. The system uses an exact match query mechanism to retrieve entries in the mapping table that perfectly correspond to the current event's urgency level and the current time period identifier, and extracts the dynamic weighting coefficient under this combination of conditions. This coefficient represents the allowable volume adjustment range for an event of a specific urgency level within a specific time period. The dynamically weighting coefficient obtained from the query is used as a weight parameter for the spatiotemporal event joint optimization and is passed to S43 for weighted calculation of the differentiated gain parameter set.

[0154] S43. Generation of Optimized Gain Parameter Set: The system performs element-wise multiplication of the dynamic weighting coefficient obtained from S42 with the differentiated gain parameter set in the environmental adaptive sound field strategy generated in S34. Specifically, for the N independent gain values ​​contained in the differentiated gain parameter set, corresponding to N horizontal angular zones, the system multiplies each independent gain value by the dynamic weighting coefficient to generate the optimized gain parameter set. This operation realizes the spatiotemporal event weighted adjustment of the basic environmental adaptive strategy: when the dynamic weighting coefficient is greater than 1, the gain of the corresponding zone is increased, achieving enhanced dynamic effects; when the dynamic weighting coefficient is less than 1, the gain of the corresponding zone is decreased, achieving interference suppression or compliant noise reduction.

[0155] S44. Generation of spatiotemporal event joint optimization strategy, specifically:

[0156] The system replaces the original differentiated gain parameter set in the environmental adaptive sound field strategy with the optimized gain parameter set calculated by S43, while retaining metadata such as target sound column identifiers and parameter effective times, generating the final spatiotemporal event joint optimization strategy. This strategy integrates spatial dimension and horizontal angular partition differentiated gain, time dimension and time period identifier corresponding weighted adjustment, and event dimension and emergency level corresponding weighted adjustment, forming a complete volume control scheme for the current specific spatiotemporal context.

[0157] S45. Strategy issuance and execution, specifically:

[0158] The system encodes the spatiotemporal event joint optimization strategy generated by S44 into control commands in a specific protocol format, such as JSON or binary messages conforming to the speaker hardware communication protocol. These commands are then published to the corresponding target speaker devices via a message middleware deployed within the system architecture. This message queue shares an asynchronous communication bus with the one used by S11 to receive data from the video analytics platform, or employs a parallel reliable message channel. Upon receiving the control command, the target speaker hardware parses the optimized gain parameter set, adjusts the gain configuration of each horizontal angular partition in its digital signal processor, and drives the power amplifier and speaker array to execute corresponding sound outputs. This achieves dynamic volume enhancement or interference suppression based on event urgency and time-sensitivity, while maintaining a compliant physical sound field.

[0159] Example 2

[0160] like Figure 2 As shown, a standardized volume control strategy generation system is used to implement a standardized volume control strategy generation method, including:

[0161] The information acquisition and analysis module is used to acquire the three-dimensional spatial constraint information and safety warning event information of the target sound column; the three-dimensional spatial constraint information includes at least the installation height, pitch angle, preset effective coverage sector angle, and information on the existence of sound reflection barriers; specifically including:

[0162] The event parsing subunit is used to receive and parse security alert event information from the video analytics platform to obtain the specific alert scenario identifier and the event urgency level.

[0163] The spatial information query subunit is used to query and obtain information such as installation height, pitch angle, preset effective coverage sector angle and point type from the resource management database based on the target device ID.

[0164] The digital map analysis subunit is used to query the digital map model based on the geographic coordinates associated with the target device ID, analyze and generate information on the existence of sound reflection barriers;

[0165] The environmental noise acquisition subunit is used to acquire real-time environmental noise data transmitted back by the target sound column or a sensor at the same location.

[0166] The fusion computing and decision-making module is used to calculate the spatial compliance acoustic power based on three-dimensional spatial constraint information, and combine it with the early warning events and location information received from the information acquisition and analysis module to generate a fusion benchmark acoustic target; specifically including:

[0167] The standard query sub-unit is used to query the scenario-location volume standard mapping table using the specific warning scenario identifier and location type information as keys to obtain the standard reference volume value;

[0168] The sound power calculation subunit is used to calculate the spatial compliance sound power based on three-dimensional spatial constraint information and sound wave attenuation model.

[0169] The weighted fusion calculation subunit is used to weight and fuse the normalized reference volume value and the spatially compliant sound power to generate a fused reference acoustic target.

[0170] The strategy mapping and generation module maps the fusion baseline acoustic target from the fusion computing and decision module into a set of differentiated gain parameters that can drive the sound columns to form a directional sound field, generating an environment-adaptive sound field strategy; specifically including:

[0171] The noise correction subunit is used to dynamically correct the fusion reference acoustic target based on environmental noise data and through a noise compensation algorithm.

[0172] The gain conversion subunit is used to convert the corrected acoustic target into a reference total gain value;

[0173] The partition parameter generation subunit is used to calculate and generate a set of differentiated gain parameters by combining the reference total gain value with the directional radiation efficiency parameters of each partition based on the effective coverage sector angle and the sound column hardware parameters.

[0174] The dynamic optimization and execution module is used to dynamically weight the set of differentiated gain parameters from the strategy mapping and generation module based on the event urgency level and time period identifier, generate a spatiotemporal event joint optimization strategy, and issue it for execution; specifically, it includes:

[0175] The time period determination subunit is used to determine the current time period identifier based on the current system time;

[0176] The dynamic weighting subunit is used to query the dynamic weighting coefficient mapping table by event urgency level and time period identifier, obtain the dynamic weighting coefficient, and perform weighted calculation on the set of differentiated gain parameters.

[0177] The instruction encoding and distribution subunit is used to encode the optimized strategy into control instructions and distribute them to the target sound column hardware for execution via message middleware.

[0178] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0179] This invention represents a fundamental leap in volume control, moving from point source adjustment to intelligent adaptation to a three-dimensional sound field, resolving the long-standing conflict between precise coverage and noise pollution. Traditional methods treat the speaker column as a simple point source, adjusting only its global output power and completely ignoring the propagation characteristics of sound in real three-dimensional space. This invention, by introducing three-dimensional spatial constraint information—installation height, pitch angle, and coverage sector—and automatically analyzing sound reflection barriers using a digital map model, achieves, for the first time, precise modeling of the physical boundaries and propagation environment of the broadcast sound field at the strategy generation level. Based on this, it calculates the spatially compliant sound power using a sound wave attenuation model and further maps it to a differentiated set of gain parameters that drive the speaker column hardware. This series of steps enables the system to generate strategies designed to shape a directional sound field, thereby focusing sound energy more precisely on the target road area while effectively suppressing spillover interference to non-target areas such as surrounding residential areas. From a technical principle perspective, this solves the core challenge in public broadcasting: ensuring clear sound while minimizing noise pollution.

[0180] A dynamic fusion decision-making mechanism driven by business rules, physical models, and spatiotemporal context has been created, significantly improving the intelligence, compliance, and social acceptability of strategies. Existing technologies either rely on fixed levels or rely solely on linear compensation based on a single factor, resulting in rigid and one-sided strategies. This invention constructs a multi-source information fusion decision engine: First, business experience and regulatory standards are solidified through a scenario-location volume specification mapping table to ensure the compliance starting point of the strategy; second, a weighted fusion algorithm intelligently harmonizes the business specification value with the spatial compliance sound power calculated based on the physical model, generating a fusion benchmark acoustic target that meets both management requirements and respects acoustic laws, resolving potential conflicts between empirical and theoretical values; finally, the event urgency level and time period identifier are introduced as dual-factor inputs, and the generated spatial sound field strategy is losslessly modulated by querying a dynamic weighted coefficient mapping table. This allows the same physical sound field to be dynamically enhanced during high-risk events in the daytime to strengthen warnings, while being appropriately suppressed at night to reflect humanistic care when handling general events, achieving an optimal balance between safety effectiveness and social tolerance.

[0181] Transforming complex standardization processes and manual judgment into a fully automated, traceable, and standardized decision-making process significantly improves system efficiency and reliability. Traditional volume compliance control heavily relies on manual review of standard documents, on-site assessments, and experience-based judgments, resulting in low efficiency and difficulty in unifying standard implementation. This invention digitizes volume control standardization documents into a built-in scene-location volume specification mapping table and calculation logic, and establishes a complete data link from automatic digital map analysis to automatic acoustic model calculation, achieving full automation from event triggering to optimal strategy generation. Administrators only need to configure high-level rules, such as defining event levels, dividing social time periods, and setting weighting coefficient tables. The system can then instantly generate optimized strategies for each specific event at a specific location from massive, high-frequency daily broadcasts, simultaneously satisfying spatial acoustic compliance, real-time environmental adaptation, and spatiotemporal social norms. This not only significantly reduces operation and maintenance costs and the risk of human error but also provides a complete strategy generation log due to the full digitization of the process, offering a solid data foundation for effect evaluation and audit optimization, and promoting the refined and intelligent upgrading of public address system management.

[0182] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art can make some modifications or alterations to other equivalent embodiments without departing from the scope of the technical means disclosed in the present invention, but these should still be regarded as the technology or embodiments that are substantially the same as the present invention.

[0183] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A method for generating a standardized volume control strategy, characterized in that, include: Obtain the scene identifier and emergency level of the safety warning event, the three-dimensional spatial constraints of the sound column, the location type, and the environmental noise data; Based on the scene identifier and point type query specification mapping table, the reference volume is obtained, and the spatial compliance sound power is calculated based on the three-dimensional spatial constraints. The fusion reference acoustic target is then generated. The noise compensation correction is performed by combining the fusion reference acoustic target with environmental noise data, and mapped to a set of differentiated gain parameters to generate an environmental adaptive sound field strategy. Based on the emergency level and time period, the set of differentiated gain parameters is dynamically weighted to generate a spatiotemporal event joint optimization strategy and then distributed.

2. The method for generating a standardized volume control strategy according to claim 1, characterized in that, The acquisition of the scene identifier and emergency level of the safety warning event, the three-dimensional spatial constraints of the sound column, the point type, and the environmental noise data specifically includes: The system receives security alert event information from the video analytics platform via a message queue and parses the predefined specific alert scenario identifier and event urgency level from its structured data fields. Based on the target device ID associated with the security warning event information, query and obtain the installation height, pitch angle, preset effective coverage sector angle, and location type information of the speaker column from the resource management database; Based on the geographic coordinates associated with the target device ID, the digital map model is queried to analyze whether there are acoustic reflectors within the spatial range corresponding to the preset effective coverage sector angle, and information on the existence of acoustic reflection barriers is generated. Together with the aforementioned information, they constitute complete three-dimensional spatial constraint information. The current environmental noise data is obtained by transmitting real-time data streams from noise sensors deployed at the target sound column or at the same location.

3. The method for generating a standardized volume control strategy according to claim 2, characterized in that, The information regarding the existence of the generated acoustic reflection barrier, together with the aforementioned information, constitutes complete three-dimensional spatial constraint information, specifically including: Obtain the precise geographic coordinates and installation orientation angle of the target device from the resource database based on the target device ID; Using the geographic coordinates as the center and the installation orientation angle as the starting direction, combined with the preset effective coverage sector angle, a three-dimensional sector spatial analysis area is defined in the digital map model; Call the spatial geometry analysis interface of the digital map model to query whether there are any entity models marked with predefined labels as having significant acoustic reflection characteristics within the sector-shaped spatial analysis area; If one or more such entity models are found, it is determined that a sound reflection barrier exists, and the type, average distance relative to the sound column, and main orientation information of each model are extracted and combined to generate structured sound reflection barrier existence information; if no such model is found, empty information indicating non-existence is generated.

4. The method for generating a standardized volume control strategy according to claim 2, characterized in that, Based on the scene identifier and point type query specification mapping table, the baseline volume is obtained. Based on the three-dimensional spatial constraints, the spatial compliance sound power is calculated, and a fusion baseline acoustic target is generated. Specifically, this includes: Using the specific warning scenario identifier and location type information as the joint input key, query the preset scenario-location volume standard mapping table to retrieve the corresponding standardized reference volume value; Based on the effective coverage sector angle and installation height in the three-dimensional spatial constraint information, the actual propagation distance of the sound wave to the farthest edge of the sector is calculated; and using the actual propagation distance and the existence information of the sound reflection barrier as input, the spatial compliance sound power required to meet the standard sound pressure level of the target point is calculated according to the sound wave attenuation model. A weighted fusion algorithm is used to fuse the normalized reference volume value and the spatially compliant sound power to generate a unified fusion reference acoustic target.

5. The method for generating a standardized volume control strategy according to claim 4, characterized in that, The calculation of the required spatial compliance sound power to meet the target point standard sound pressure level specifically includes: Based on the installation height and pitch angle, the actual propagation distance of sound from the position of the sound column to the farthest ground edge point defined by the effective coverage sector angle is calculated through geometric projection relationship; Based on the location type information of the target sound column, the volume control standardization standard is queried to determine the standard sound pressure level value of the corresponding location as the expected sound pressure level of the target point; Based on the spherical wave attenuation model, the free field path loss is calculated according to the actual propagation distance; The presence information of the acoustic reflection barrier is analyzed, and based on the type, average distance and orientation of the acoustic reflectors therein, the additional attenuation caused by them to sound wave propagation is evaluated, and an environmental additional loss compensation value is determined. The standard sound pressure level, free-field path loss, and environmental additional loss compensation value are added together to calculate the spatial compliant sound power required for the column source to achieve compliant coverage.

6. The method for generating a standardized volume control strategy according to claim 5, characterized in that, Based on the installation height and pitch angle, the actual propagation distance of sound from the sound column location to the farthest ground edge point defined by the effective coverage sector angle is calculated using geometric projection relationships. Specifically, this includes: Establish a three-dimensional spatial coordinate system with the sound column installation point as the origin, where the Z-axis is perpendicular to the ground and pointing upwards, and the XOY plane is parallel to the ground; Based on the installation height and pitch angle, calculate the projection radius on the XOY plane when the main axis of the sound wave is projected onto the ground; Based on the projection radius and the effective coverage sector angle, determine the point on the ground projection profile of the outer edge of the sector that is farthest from the origin, and calculate the horizontal distance from the origin of the farthest point on the XOY plane. Based on the distance formula between two points in three-dimensional space, and combined with the installation height and horizontal distance, the actual propagation distance of sound from the position of the sound column to the farthest ground point is calculated.

7. The method for generating a standardized volume control strategy according to claim 6, characterized in that, Determining an environmental additional loss compensation value specifically includes: Based on the type of acoustic reflector in the acoustic reflection barrier information, query the preset acoustic material reflection loss benchmark table to obtain the benchmark reflection loss value corresponding to the material type. Based on the average distance and orientation of the acoustic reflector, combined with the installation position of the sound column and the effective coverage sector, the proportion of acoustic shadowing area or effective reflection enhancement caused by the reflector to the target coverage area is evaluated by geometric calculation. Based on the proportion of the acoustic shadow zone or the effective reflection enhancement proportion, the reference reflection loss value is adjusted accordingly or its sign is inverted, and the environmental additional loss compensation value is finally calculated and determined.

8. The method for generating a standardized volume control strategy according to claim 4, characterized in that, The fusion benchmark acoustic target is combined with environmental noise data for noise compensation correction, mapped to a set of differentiated gain parameters, and an environmental adaptive sound field strategy is generated, specifically including: According to the preset noise compensation algorithm, the environmental noise data is used to dynamically correct the fusion reference acoustic target, and the noise-corrected acoustic target is generated. Based on the hardware performance parameters of the target sound column, the noise-corrected acoustic target is converted into a reference total gain value required for the sound column to achieve the noise-corrected acoustic target under rated operating conditions. Based on the effective coverage sector angle in the three-dimensional spatial constraint information, N horizontal angular partitions are determined, and the directional radiation efficiency parameter corresponding to each partition is obtained; The reference total gain value is combined with the directional radiation efficiency parameter of each partition to calculate and generate an independent gain value for each partition. All N independent gain values ​​constitute the differentiated gain parameter set. The differentiated gain parameter set is encapsulated with the target sound column identifier and the parameter effective time to generate the environment adaptive sound field strategy.

9. The method for generating a standardized volume control strategy according to claim 8, characterized in that, Based on the aforementioned emergency level and time period, a set of differentiated gain parameters is dynamically weighted to generate and distribute a spatiotemporal event joint optimization strategy, specifically including: Based on the current system time, and referring to the preset social work and rest time division rules, determine the current time period identifier; Using the event urgency level and time period identifier as the combined input key, query the preset dynamic weighting coefficient mapping table to obtain the corresponding dynamic weighting coefficient; The dynamic weighting coefficients are multiplied by each independent gain value in the differentiated gain parameter set in the environmental adaptive sound field strategy to generate an optimized gain parameter set. The environmental adaptive sound field strategy is updated with the optimized gain parameter set to generate the final spatiotemporal event joint optimization strategy; The spatiotemporal event joint optimization strategy is encoded into control instructions in a specific protocol format and sent to the target sound column hardware for execution via a message middleware.

10. A standardized volume control strategy generation system, characterized in that, A method for generating a standardized volume control strategy according to any one of claims 1-9 includes: The information acquisition and analysis module is used to acquire the three-dimensional spatial constraint information and safety warning event information of the target sound column; the three-dimensional spatial constraint information includes at least the installation height, pitch angle, preset effective coverage sector angle, and information on the existence of sound reflection barriers; The fusion computing and decision-making module is used to calculate the spatial compliance acoustic power based on the three-dimensional spatial constraint information, and combine the early warning events and location information received from the information acquisition and analysis module to generate a fusion reference acoustic target. The strategy mapping and generation module is used to map the fusion baseline acoustic target from the fusion computing and decision module into a set of differentiated gain parameters that can drive the sound column to form a directional sound field, and generate an environment-adaptive sound field strategy. The dynamic optimization and execution module is used to dynamically weight the set of differentiated gain parameters from the strategy mapping and generation module based on the event urgency level and time period identifier, generate a spatiotemporal event joint optimization strategy, and issue it for execution.

Images