A method and apparatus for calculating a representation of a complex sound field, and an electronic device

Abstract

The application discloses a kind of complex sound field characterization calculation method, device and electronic equipment, method includes: obtaining target image marked with preset pattern;The region corresponding to preset pattern in target image is ideal target area;The final image of complex sound field information distribution of characterization reconstruction is obtained by simulating target image based on iterative angular spectrum method;The region corresponding to preset pattern in final image is final target area;Based on the sound pressure of each pixel in ideal target area and final target area, the reconstruction similarity of final image and target image is calculated for the quality evaluation of reconstruction complex sound field.The reconstruction similarity of the application links the sound pressure of final target area and ideal target area in sound field, can better evaluate the effectiveness of reconstructed image, and the reconstruction similarity is used as a kind of characterization mode for measuring the quality of sound field reconstruction.The reconstruction similarity can be combined with reconstruction efficiency and other methods to more perfectly measure the image quality of sound field, and be suitable for a variety of structured complex sound field.

Description

Technical Field

[0001] This invention belongs to the field of ultrasonic sound field technology, specifically relating to a method, apparatus, and electronic device for characterizing and calculating complex sound fields. Background Technology

[0002] Reconstructing complex ultrasonic fields plays a crucial role in many applications such as ultrasound imaging and acoustic tweezers. Based on the complexity of the information contained within the sound field, they can be divided into two types: simple focused sound fields, whose sound field quality is evaluated based on their lateral and longitudinal resolution; and complex structured sound fields, which are typically compared based on the efficiency of reconstructing the target area versus the entire reconstructed sound field. However, this method is still insufficient and incomplete in measuring the quality of the reconstructed ultrasonic field, lacking methods and criteria for evaluating the sound field quality specifically for the target area. Summary of the Invention

[0003] To address the aforementioned problems in the prior art, this invention provides a method, apparatus, electronic device, and storage medium for characterizing complex sound fields. The technical problem to be solved by this invention is achieved through the following technical solution:

[0004] In a first aspect, embodiments of the present invention provide a method for characterizing and calculating complex sound fields, the method comprising:

[0005] Acquire a target image marked with a preset pattern; wherein the target image is a black and white image; and the area corresponding to the preset pattern in the target image is an ideal target area;

[0006] The final image representing the distribution of complex sound field information reconstructed is obtained by simulation of the target image using the iterative angular spectrum method; wherein, the region corresponding to the preset pattern in the final image is the final target region; and the sound pressure is distributed at each pixel position in the target image and the final image.

[0007] Based on the sound pressure of each pixel in the ideal target region and the final target region, the reconstruction similarity between the final image and the target image is calculated for quality assessment of the reconstruction of complex sound fields.

[0008] In one embodiment of the present invention, the final image representing the distribution of complex sound field information reconstructed is obtained from the target image using iterative angular spectrum method simulation, including:

[0009] The ideal target region is defined as the amplitude constraint condition of the imaging plane, and the pixel amplitude in the ideal target region is taken as the pixel amplitude corresponding to the imaging plane.

[0010] Iterative calculations of the angular spectrum method are performed on the holographic plane and the imaging plane based on Fourier transform, preserving the forward propagation phase information. After the iteration, the phase information of the preset image stored in the holographic plane is obtained, and the final image representing the distribution of the reconstructed complex sound field information generated at the distance of the imaging plane is obtained; wherein, the holographic plane is connected to ultrasonic waves.

[0011] In one embodiment of the present invention, the reconstruction similarity between the final image and the target image is calculated based on the sound pressure levels of each pixel in the ideal target region and the final target region, including:

[0012] Based on the sound pressure levels of each pixel in the ideal target region and the final target region, the reconstruction similarity between the final image and the target image is calculated using a preset reconstruction similarity formula; wherein, the preset reconstruction similarity formula includes:

[0013]

[0014] Where s represents the reconstruction similarity; T represents the final target region; D represents the ideal target region; p z,(i,j) This represents the sound pressure level at pixel (i,j).

[0015] In one embodiment of the present invention, the preset reconstruction similarity formula is derived based on the relationship between sound power, sound intensity, and sound pressure during the propagation of sound waves; wherein,

[0016] The expression for sound power is:

[0017]

[0018] The expression for sound intensity is:

[0019]

[0020] Among them, P z P represents the acoustic power when the target area is T. z =P z,T , representing the acoustic power of the final target area; when the target area is D, P z =P z,D , represents the acoustic power of the ideal target region; Δx, Δy represent the size of the pixel in the corresponding direction; ρ represents the density of the medium; c represents the speed of sound;

[0021] The derived formula for reconstruction similarity is expressed as follows:

[0022] In one embodiment of the present invention, the reconstructed complex sound field is a complex structured sound field.

[0023] In one embodiment of the present invention, the sound pressure amplitude at a pixel in the target image is 1; the sound pressure at the pixel in the target image is normalized.

[0024] In one embodiment of the present invention, the preset pattern includes:

[0025] S, i, m, and Similarity.

[0026] Secondly, embodiments of the present invention provide a computational apparatus for characterizing complex sound fields, the apparatus comprising:

[0027] A target image acquisition module is used to acquire a target image marked with a preset pattern; wherein, the target image is a black and white image; and the area corresponding to the preset pattern in the target image is an ideal target area;

[0028] The final image generation module is used to simulate the target image using the iterative angular spectrum method to obtain a final image representing the distribution of complex sound field information reconstructed; wherein, the region corresponding to the preset pattern in the final image is the final target region; and the sound pressure is distributed at each pixel position in the target image and the final image.

[0029] The reconstruction similarity calculation module is used to calculate the reconstruction similarity between the final image and the target image based on the sound pressure of each pixel in the ideal target region and the final target region, for the quality assessment of the reconstructed sound field.

[0030] Thirdly, embodiments of the present invention provide an electronic device, including a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus;

[0031] The memory is used to store computer programs;

[0032] When the processor executes the program stored in the memory, it implements the steps of the complex sound field characterization calculation method provided in the embodiments of the present invention.

[0033] Fourthly, embodiments of the present invention provide a computer-readable storage medium storing a computer program, wherein the computer program, when executed by a processor, implements the steps of the method for characterizing and calculating complex sound fields provided in the embodiments of the present invention.

[0034] The beneficial effects of this invention are:

[0035] The solution provided in this invention first acquires a target image marked with a preset pattern; secondly, it simulates the target image using the iterative angular spectrum method to obtain a final image representing the distribution of complex sound field information for reconstruction; finally, based on the sound pressure of each pixel in the ideal target region and the final target region, it calculates the reconstruction similarity between the final image and the target image, which is used for quality assessment of the reconstructed complex sound field. The reconstruction similarity of this invention links the sound pressure of the final target region and the ideal target region within the sound field, enabling a better evaluation of the effectiveness of the reconstructed image, thus using reconstruction similarity as a representation of the sound field reconstruction quality. The reconstruction similarity of this invention can be combined with other methods such as reconstruction efficiency to comprehensively measure the image quality of the sound field and is applicable to various structured complex sound fields, having important applications in evaluating the ideality of ultrasonic field reconstruction. Attached Figure Description

[0036] Figure 1 This is a flowchart illustrating a method for characterizing and calculating a complex sound field, as provided in an embodiment of the present invention.

[0037] Figure 2a This is a schematic diagram of the pixel distribution of the sound field image in an embodiment of the present invention. Figure 2a The left image is the final image of the normalized sound pressure reconstructed by the iterative angular spectrum method, and the right image is the target image with a sound pressure amplitude of 1 as input by the iterative angular spectrum method.

[0038] Figure 2b This is a sound pressure amplitude distribution map of the ideal target area corresponding to the patterns of letters S, i, and m in an embodiment of the present invention. Figure 2b The left image is the letter S, the middle image is the letter i, and the right image is the letter m;

[0039] Figure 2c This is a sound pressure amplitude distribution map of the ideal target area corresponding to the Similarity pattern in this embodiment of the invention;

[0040] Figure 2d This is a simulation diagram of the final target region's sound pressure amplitude distribution corresponding to the patterns of letters S, i, and m in an embodiment of the present invention. Figure 2d The left image is the letter S, the middle image is the letter i, and the right image is the letter m;

[0041] Figure 2e This is a simulated sound pressure amplitude distribution map of the final target area corresponding to the Similarity pattern in this embodiment of the invention;

[0042] Figure 2f This is a phase distribution diagram of the holographic plane corresponding to the patterns of letters S, i, and m in an embodiment of the present invention. Figure 2f The left image is the letter S, the middle image is the letter i, and the right image is the letter m;

[0043] Figure 2g This is the phase distribution map of the holographic plane corresponding to the Similarity pattern in this embodiment of the invention. Figure 2g The left image is the letter S, the middle image is the letter i, and the right image is the letter m;

[0044] Figure 3 A schematic diagram of the structure of a complex sound field characterization computing device provided in an embodiment of the present invention;

[0045] Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0046] 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.

[0047] To comprehensively measure the image quality of a sound field and to be applicable to various structured and complex sound fields, embodiments of the present invention provide a method, apparatus, electronic device, and storage medium for characterizing complex sound fields.

[0048] It should be noted that the execution entity of the complex sound field characterization calculation method provided in this embodiment of the invention can be a complex sound field characterization calculation device, which can run in an electronic device. This electronic device can be a server or a terminal device, but is not limited to these.

[0049] In a first aspect, embodiments of the present invention provide a method for characterizing and calculating complex sound fields, such as... Figure 1 As shown, it may include the following steps:

[0050] S1, Obtain the target image marked with a preset pattern;

[0051] The target image is a black and white image; the area corresponding to the preset pattern in the target image is the ideal target area; the preset pattern can be set as needed, for example, in one embodiment, the preset pattern may include: S, i, m and Similarity, etc.

[0052] S2, the final image representing the distribution of complex sound field information reconstructed is obtained by simulation of the target image using the iterative angular spectrum method;

[0053] In this embodiment of the invention, the region corresponding to the preset pattern in the final image is the final target region; the pixel distribution corresponding to the preset pattern of the complex sound field, that is, the target region distribution of the complex structured sound field is composed of multiple pixels of the same size, and a certain sound pressure value is distributed at the corresponding pixel position. In other words, sound pressure is distributed at each pixel position in the target image and the final image. Specifically, the sound pressure amplitude at the pixel in the target image is 1.

[0054] For details on the iterative angular spectrum method, please refer to the following text and related technical explanations.

[0055] S3, based on the sound pressure of each pixel in the ideal target region and the final target region, calculate the reconstruction similarity between the final image and the target image, which is used for quality assessment of the reconstruction of complex sound fields.

[0056] The reconstructed complex sound field can be a structured complex sound field. Corresponding to a sound pressure amplitude of 1 at a pixel in the target image, the sound pressure at the pixel in the target image is normalized; that is, the target image represents a sound field distribution with normalized sound pressure values.

[0057] In this embodiment of the invention, a numerical value representing the sound pressure distribution can be obtained for the sound pressure of each pixel in the ideal target region, and a numerical value representing the sound pressure distribution can also be obtained for the sound pressure of each pixel in the final target region. By performing a mathematical calculation on the similarity between these two values, a processed numerical value can be obtained to represent the reconstruction similarity between the final image and the target image. It can be understood that the reconstruction similarity can measure the degree of similarity between the target image and the final image obtained by reconstructing the complex sound field, and thus evaluate the quality of the reconstructed complex sound field.

[0058] As can be seen, the embodiments of the present invention provide a method for characterizing and calculating reconstructed complex sound fields. By comparing the sound field information of the final target region in the image with the sound field information of the ideal target region, the reconstruction similarity is obtained. This method can effectively measure the image quality of the sound field and is applicable to various structured complex sound fields.

[0059] In one optional implementation, the final image representing the distribution of complex sound field information reconstructed is obtained by simulating the target image using the iterative angular spectrum method, including:

[0060] A1, the ideal target region is defined as the amplitude constraint condition of the imaging plane, and the pixel amplitude in the ideal target region is taken as the pixel amplitude corresponding to the imaging plane;

[0061] A2, based on Fourier transform, iterative calculations are performed using the iterative angular spectrum method on the holographic plane and the imaging plane, retaining the forward propagation phase information. After the iteration, the phase information of the preset pattern stored in the holographic plane is obtained, and the final image representing the distribution of the reconstructed complex sound field information generated at the distance from the imaging plane is obtained; wherein, the holographic plane is connected to ultrasonic waves.

[0062] It is understandable that the information content of the sound field directly depends on the number of independently controllable pixels in the hologram of the reconstructed sound field. This invention connects the sound field information of the ideal target region with the sound field information of the final target region. Based on the iterative angular spectrum method, this invention connects the phase hologram of the holographic plane with the sound field of the imaging plane through Fourier transform. The ideal target region is defined as the amplitude constraint condition of the imaging plane, and the imaging plane is replaced with the ideal target value, i.e., the pixel amplitude in the ideal target region is used as the pixel amplitude corresponding to the imaging plane. In this invention, the sound wave recovers the stored wavefront information through the phase hologram, ultimately forming a complex sound field with a preset pattern. The iterative angular spectrum method performs iterative calculations back and forth between the holographic plane and the imaging plane, retaining the forward propagation phase information, and obtaining the phase information of the preset pattern holographic plane and the distribution of the final target complex sound field information generated at the distance from the imaging plane. Therefore, after the iteration, the final image is obtained using the phase information of the holographic plane and the distribution of the target complex sound field information generated at the distance from the imaging plane. This invention, by correlating the sound pressure of the final target pixel distribution area generated within a complex sound field with the sound pressure of the ideal target pixel distribution area, can effectively evaluate the effectiveness of various complex images. By combining this with other methods, it can more comprehensively evaluate the quality of various complex sound field images.

[0063] For detailed calculations of the iterative angular spectrum method, please refer to the relevant technical explanations; they will not be elaborated upon here. Simulation tools can include MATLAB, etc.

[0064] Since the propagation of sound waves is accompanied by energy transfer, the structured and complex sound field reconstructed from the acoustic phase hologram contains more sound field details and a larger spatial range. Therefore, the embodiments of the present invention can derive a preset reconstruction similarity formula based on the relationship between sound power, sound intensity and sound pressure. The sound pressure of the final target pixel distribution area in the sound field is compared with the sound pressure of the ideal target pixel distribution area. This can better evaluate the effectiveness of various complex reconstructed images, and thus use the overall reconstruction similarity as a way to measure the quality of sound field reconstruction.

[0065] Specifically, the preset reconstruction similarity formula is derived based on the relationship between sound power, sound intensity, and sound pressure during sound wave propagation; wherein,

[0066] The expression for sound power is:

[0067]

[0068] The expression for sound intensity is:

[0069]

[0070] Among them, P z P represents the acoustic power when the target area is T. z =P z,T , representing the acoustic power of the final target area; when the target area is D, P z =P z,D , representing the acoustic power of the ideal target region; that is, the target region T is the actual final set of pixels corresponding to the positions of the target image with amplitude values ​​greater than 0, obtained after iterative calculation. The ideal target region D is the set of pixels corresponding to the positions of the ideal target regions with non-zero amplitude values ​​corresponding to the preset pattern; I z,(i,j) This indicates the sound intensity of the corresponding target area.

[0071] Δx and Δy represent the sampling distances along the x and y coordinates on the target observation plane, respectively, and also indicate the size of the pixel in the corresponding direction; p z,(i,j) ρ represents the sound pressure at pixel (i,j); ρ represents the density of the medium; c represents the speed of sound; (i,j) represents the location of the pixel.

[0072] The derived formula for reconstruction similarity is expressed as follows:

[0073] Based on this, the reconstruction similarity between the final image and the target image is calculated based on the sound pressure levels of each pixel in the ideal target region and the final target region, including:

[0074] Based on the sound pressure levels of each pixel in the ideal target region and the final target region, the reconstruction similarity between the final image and the target image is calculated using a preset reconstruction similarity formula; wherein, the preset reconstruction similarity formula includes:

[0075]

[0076] Where s represents the reconstruction similarity; T represents the final target region; D represents the ideal target region; p z,(i,j) This represents the sound pressure level at pixel (i,j).

[0077] The solution provided in this invention first acquires a target image marked with a preset pattern; secondly, it simulates the target image using the iterative angular spectrum method to obtain a final image representing the distribution of complex sound field information for reconstruction; finally, based on the sound pressure of each pixel in the ideal target region and the final target region, it calculates the reconstruction similarity between the final image and the target image, which is used for quality assessment of the reconstructed complex sound field. The reconstruction similarity of this invention links the sound pressure of the final target region and the ideal target region within the sound field, enabling a better evaluation of the effectiveness of the reconstructed image, thus using reconstruction similarity as a representation of the sound field reconstruction quality. The reconstruction similarity of this invention can be combined with other methods such as reconstruction efficiency to comprehensively measure the image quality of the sound field and is applicable to various structured complex sound fields, having important applications in evaluating the ideality of ultrasonic field reconstruction.

[0078] To facilitate understanding of the embodiments of the present invention, relevant simulation results are given below.

[0079] Reference Figure 2a As shown, this embodiment provides a method for characterizing and calculating complex sound fields by relating the square of the sound pressure in the final target region (left image 2a) to the square of the sound pressure in the ideal target region (right image 2a). In this embodiment, the number of pixels in the unified overall image is 200×200, and the pixel size is 150μm.

[0080] Reference Figure 2b As shown, Figure 2b The normalized sound pressure amplitude distribution of the ideal target region corresponding to the patterns of letters S, i, and m in this embodiment is given, where the left figure is the letter S, the middle figure is the letter i, and the right figure is the letter m;

[0081] Reference Figure 2c As shown, Figure 2c The normalized sound pressure amplitude distribution map of the ideal target region corresponding to the Similarity pattern in this embodiment is given;

[0082] Reference Figure 2d As shown in this embodiment, the relationship between the sound pressure distribution of the final target region and the sound pressure of the ideal target region is calculated and simulated using MATLAB based on the iterative angular spectrum method. This allows for a quantitative assessment of the similarity between the reconstructed complex sound field and the ideal situation, including the normalized sound pressure amplitude information of the simulated target patterns of letters S, i, and m.

[0083] Reference Figure 2e As shown, Figure 2e The normalized sound pressure amplitude distribution map of the final target area corresponding to the Similarity pattern in this embodiment is given.

[0084] Reference Figure 2f As shown, in this embodiment, phase holograms of different patterns can be calculated by iterative angular spectrum method. After 50 iterations, when the holographic plane propagates forward to the imaging plane, the information stored in the wavefront can be recovered, thereby obtaining the complex sound field of the target area reconstructed by different patterns on the target imaging plane, including the sound field information of the final image generated by the patterns corresponding to the letters S, i, and m.

[0085] Embodiments of this invention can generate phase holograms with different patterns. Sound waves are processed through the phase holograms to recover stored wavefront information, forming a complex sound field with a final specific pattern, which is then compared with the ideal target sound field information. For example... Figure 2d and Figure 2f The final normalized sound pressure amplitude distribution and the phase distribution of the holographic plane generated by the patterns of letters S, i, and m, respectively, are shown below. Figure 2e and Figure 2g The final normalized sound pressure amplitude distribution and the phase distribution of the holographic plane generated by the Similarity pattern are shown respectively.

[0086] It is evident that high-fidelity target complex sound fields can be generated through phase holograms with different patterns. Based on the relationship between the normalized sound pressure level at the pixel location corresponding to the calculated simulated amplitude and the normalized sound pressure level at the pixel location corresponding to the ideal target image amplitude, the image reconstruction quality of different complex structured sound fields can be calculated.

[0087] It should be noted that in the above embodiments, the amplitude in the holographic plane is set as the output pressure distribution of the transducer. For ease of calculation, the transducer plane amplitude is set to an ideal value of 1. Different patterns generate corresponding complex sound fields in the hologram. The thickness of the simulated ultrasonic transducer is determined by its designed operating frequency. In this embodiment, the simulation parameters include a piezoelectric material of PZT-4 with a diameter of 15 mm and a designed operating frequency of 5 MHz. The reconstruction similarities of the different patterns calculated in the above embodiments are approximately 38.53%, 31.60%, 31.40%, and 37.70%, respectively.

[0088] As can be seen, the reconstruction similarity of this embodiment of the invention compares the square of the sound pressure in the final target region generated within the reconstructed complex sound field with the square of the sound pressure in the ideal target region sound field, quantitatively evaluating the similarity between the reconstructed complex sound field and the ideal situation, thereby providing a better assessment of the effectiveness of various complex images. The reconstruction similarity of the above embodiments can be combined with other methods to comprehensively measure the image quality of the sound field and is applicable to various structured complex sound fields, having important applications in evaluating the ideality of ultrasonic fields.

[0089] Secondly, corresponding to the above method embodiments, this invention also provides a device for characterizing and calculating complex sound fields, such as... Figure 3As shown, the device includes:

[0090] The target image acquisition module 301 is used to acquire a target image marked with a preset pattern; wherein, the target image is a black and white image; and the area corresponding to the preset pattern in the target image is an ideal target area;

[0091] The final image generation module 302 is used to simulate the target image based on the iterative angular spectrum method to obtain a final image representing the distribution of complex sound field information reconstructed; wherein, the region corresponding to the preset pattern in the final image is the final target region; and the sound pressure is distributed at each pixel position in the target image and the final image.

[0092] The reconstruction similarity calculation module 303 is used to calculate the reconstruction similarity between the final image and the target image based on the sound pressure of each pixel in the ideal target region and the final target region, for the quality assessment of the reconstructed sound field.

[0093] Optionally, when the final image generation module 302 obtains the final image representing the distribution of complex sound field information reconstructed from the target image using the iterative angular spectrum method simulation, it is specifically used for:

[0094] The ideal target region is defined as the amplitude constraint condition of the imaging plane, and the pixel amplitude in the ideal target region is taken as the pixel amplitude corresponding to the imaging plane.

[0095] Iterative calculations of the angular spectrum method are performed on the holographic plane and the imaging plane based on Fourier transform, preserving the forward propagation phase information. After the iteration, the phase information of the preset image stored in the holographic plane is obtained, and the final image representing the distribution of the reconstructed complex sound field information generated at the distance of the imaging plane is obtained; wherein, the holographic plane is connected to ultrasonic waves.

[0096] Optionally, when calculating the reconstruction similarity calculation module 303 based on the sound pressure of each pixel in the ideal target region and the final target region, it is specifically used for:

[0097] Based on the sound pressure levels of each pixel in the ideal target region and the final target region, the reconstruction similarity between the final image and the target image is calculated using a preset reconstruction similarity formula; wherein, the preset reconstruction similarity formula includes:

[0098]

[0099] Where s represents the reconstruction similarity; T represents the final target region; D represents the ideal target region; p z,(i,j) This represents the sound pressure level at pixel (i,j).

[0100] Optionally, the preset reconstruction similarity formula is derived based on the relationship between sound power, sound intensity, and sound pressure during sound wave propagation; wherein,

[0101] The expression for sound power is:

[0102]

[0103] The expression for sound intensity is:

[0104]

[0105] Among them, P z P represents the acoustic power when the target area is T. z =P z,T , representing the acoustic power of the final target area; when the target area is D, P z =P z,D , represents the acoustic power of the ideal target region; Δx, Δy represent the size of the pixel in the corresponding direction; ρ represents the density of the medium; c represents the speed of sound;

[0106] The derived formula for reconstruction similarity is expressed as follows:

[0107] Optionally, the reconstructed complex sound field is a complex structured sound field.

[0108] Optionally, the sound pressure amplitude at a pixel in the target image is 1; the sound pressure at a pixel in the target image is normalized.

[0109] Optionally, the preset pattern includes:

[0110] S, i, m, and Similarity.

[0111] For details on the specific processing methods of each module in the computational device for representing this complex sound field, please refer to the relevant content in the first part above, which will not be repeated here.

[0112] In the solution provided by this invention, reconstruction similarity links the sound pressure of the final target region and the ideal target region within the sound field, which can better evaluate the effectiveness of the reconstructed image. Therefore, reconstruction similarity can be used as a representation of the quality of sound field reconstruction. The reconstruction similarity of this invention can be combined with other methods such as reconstruction efficiency to comprehensively measure the image quality of the sound field, and is applicable to various structured and complex sound fields. It has important applications in evaluating the ideality of ultrasonic field reconstruction.

[0113] Thirdly, embodiments of the present invention also provide an electronic device, such as... Figure 4As shown, it includes a processor 401, a communication interface 402, a memory 403, and a communication bus 404, wherein the processor 401, the communication interface 402, and the memory 403 communicate with each other through the communication bus 404.

[0114] The memory is used to store computer programs;

[0115] When the processor executes the program stored in the memory, it implements the step of characterizing any complex sound field provided in the first aspect of the present invention.

[0116] The communication bus mentioned in the above electronic devices can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in the diagram, but this does not mean that there is only one bus or one type of bus.

[0117] The communication interface is used for communication between the aforementioned electronic devices and other devices.

[0118] The memory may include random access memory (RAM) or non-volatile memory (NVM), such as at least one disk storage device. Optionally, the memory may also be at least one storage device located remotely from the aforementioned processor.

[0119] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0120] The method provided in this invention can be applied to electronic devices. Specifically, the electronic device can be a desktop computer, a portable computer, a smart mobile terminal, a server, etc. No limitation is made herein; any electronic device that can implement this invention falls within the protection scope of this invention.

[0121] Fourthly, corresponding to the complex sound field characterization calculation provided in the first aspect, the present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of characterization calculation of any complex sound field provided in the first aspect of the present invention.

[0122] For the embodiments of the device / electronic device / storage medium, since they are basically similar to the method embodiments, the description is relatively simple, and relevant parts can be referred to in the description of the method embodiments.

[0123] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. In addition, those skilled in the art can combine and integrate the different embodiments or examples described in this specification.

[0124] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. A method of calculating a representation of a complex sound field, characterized in that, The method comprises: acquiring a target image marked with a preset pattern; wherein the target image is a black-and-white image; a region corresponding to the preset pattern in the target image is an ideal target region; simulating, based on an iterative angular spectrum method, a final image representing distribution of reconstructed complex sound field information of the target image; wherein a region corresponding to the preset pattern in the final image is a final target region; sound pressures are distributed at each pixel position of the target image and the final image; calculating, based on sound pressures of each pixel in the ideal target region and the final target region, a reconstruction similarity of the final image and the target image, for quality evaluation of reconstruction of the complex sound field.

2. The method of claim 1, wherein, The simulating, based on the iterative angular spectrum method, of the final image representing distribution of reconstructed complex sound field information of the target image comprises: defining the ideal target region as an amplitude constraint condition of an imaging plane, and taking pixel amplitudes in the ideal target region as pixel amplitudes corresponding to the imaging plane; performing iterative calculation of the iterative angular spectrum method based on Fourier transform on a holographic plane and the imaging plane, retaining phase information of forward propagation, obtaining, after the iteration ends, phase information of the preset image stored in the holographic plane, and obtaining the final image representing distribution of reconstructed complex sound field information generated at a distance of the imaging plane; wherein the holographic plane is accessed by an ultrasonic wave.

3. The method of claim 1, wherein, The calculating, based on sound pressures of each pixel in the ideal target region and the final target region, of the reconstruction similarity of the final image and the target image comprises: calculating, based on sound pressures of each pixel in the ideal target region and the final target region, the reconstruction similarity of the final image and the target image by using a preset reconstruction similarity formula; wherein the preset reconstruction similarity formula comprises: where s represents a reconstruction similarity; T represents the final target region; D represents the ideal target region; p z,(i,j) represents the sound pressure at pixel (i, j).

4. The method of claim 3, wherein, The preset reconstruction similarity formula is derived based on a relationship among sound power, sound intensity and sound pressure in a propagation process of a sound wave; wherein an expression of the sound power is: an expression of the sound intensity is: where P z represents the sound power, when target area is T, P z z,T represents the sound power of the final target area; when target area is D, P z z,D represents the sound power of the ideal target area; Δx, Δy represent the size of the pixel point in the corresponding direction; ρ represents the density of the medium; c represents the sound speed;​​ The derived reconstruction similarity formula is expressed as:

5. The method of claim 1, wherein, The reconstructed complex sound field is a complex structured sound field.

6. The method of claim 1, wherein, The sound pressure amplitude at the pixel in the target image is 1; the sound pressure at the pixel in the target image is normalized.

7. The method of claim 1, wherein, The preset pattern comprises: S, i, m and Similarity.

8. A device for computing a representation of a complex sound field, characterized by The method comprises: a target image acquisition module configured to acquire a target image marked with a preset pattern; wherein the target image is a black-and-white image; a region corresponding to the preset pattern in the target image is an ideal target region; a final image generation module configured to simulate, based on an iterative angular spectrum method, a final image representing distribution of reconstructed complex sound field information of the target image; wherein a region corresponding to the preset pattern in the final image is a final target region; sound pressures are distributed at each pixel position of the target image and the final image; a reconstruction similarity calculation module configured to calculate, based on sound pressures of each pixel in the ideal target region and the final target region, a reconstruction similarity of the final image and the target image, for quality evaluation of reconstruction of the sound field.

9. An electronic device, comprising: The device comprises a processor, a communication interface, a memory and a communication bus, wherein the processor, the communication interface and the memory complete communication with each other through the communication bus; the memory is used to store a computer program. The processor is configured to implement the method steps of any one of claims 1-7 when executing the program stored in the memory. 10.A computer readable storage medium, comprising: The computer readable storage medium stores a computer program, and the computer program is configured to implement the method steps of any one of claims 1-7 when executed by a processor.

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