Image acquisition method, system, electronic device, storage medium and program product

Abstract

This application provides an image acquisition method, system, electronic device, storage medium, and program product. One specific embodiment of the method includes: acquiring the received signal strength indication value of a target object acquired by a UWB radar under conditions of light-transmitting material obstruction, and the measured distance between the UWB radar and the target object; determining correction information based on the received signal strength indication value; correcting the measured distance based on the correction information; and acquiring an image of the target object based on the corrected distance. This method can obtain relatively clear images.

Description

Technical Field

[0001] This application relates to the field of image acquisition technology, and more specifically, to an image acquisition method, system, electronic device, storage medium, and program product. Background Technology

[0002] UWB radar, or Ultra-Wideband (UWB) radar, is a type of radar that operates using a very wide frequency spectrum. Compared to traditional narrowband or wideband radar systems, UWB radar uses a relatively wider frequency range, typically with bandwidths exceeding several GHz, which allows it to transmit and receive signals in extremely short times.

[0003] Furthermore, UWB radar has the ability to penetrate non-metallic materials, thus enabling it to detect the distance information of objects when they are obscured by non-metallic materials.

[0004] In some applications, UWB radar can be used to detect the distance information of objects when they are blocked by light-transmitting materials. However, the detected distance information is inaccurate due to the influence of the light-transmitting materials, resulting in a lack of clear images when image acquisition is performed based on this distance information. Summary of the Invention

[0005] The purpose of this application is to provide an image acquisition method, system, electronic device, storage medium, and program product to obtain a clearer image.

[0006] Firstly, embodiments of this application provide an image acquisition method, which includes: acquiring a received signal strength indication value of a target object acquired by a UWB radar under conditions of light-transmitting material obstruction, and a measured distance between the UWB radar and the target object; determining correction information based on the received signal strength indication value; correcting the measured distance based on the correction information; and acquiring an image of the target object based on the corrected distance. Here, for the case where the target object is obstructed by light-transmitting material, correction information can be determined based on the received signal strength indication value acquired by the UWB radar, and then the measured distance can be corrected based on this correction information, thereby reducing the error between the measured distance and the true distance and obtaining more accurate distance information. Thus, when this distance information is used to assist a camera in acquiring images, the deviation between the focus position and the true position of the object can be reduced, resulting in a clearer image.

[0007] Optionally, determining the correction information based on the received signal strength indication value includes: searching for correction information corresponding to the received signal strength indication value in a preset relationship table; the preset relationship table stores the correspondence between the received signal strength indication value and the correction information. This is more convenient and faster.

[0008] Optionally, the correction information includes the thickness information of the light-transmitting material, the ranging error coefficient caused by the light-transmitting material per unit thickness; and the preset relationship table is calibrated based on the following steps: obtaining the sample received signal intensity indication value of the sample object collected by the UWB radar under the condition of sample light-transmitting material obstruction of different thicknesses, and the actual sample distance between the sample object and the UWB radar; obtaining the actual sample distance between the UWB radar and the sample object; obtaining the thickness information corresponding to the sample light-transmitting material of different thicknesses respectively; for each sample received signal intensity indication value, determining the sample ranging error coefficient corresponding to the sample received signal intensity indication value based on the thickness information of the sample light-transmitting material when the sample received signal intensity indication value is obtained, the actual sample distance, and the actual sample distance; establishing the correspondence between the sample received signal intensity indication value, the sample ranging error coefficient, and the thickness information to obtain the preset relationship table. Here, the correspondence between the received signal strength indication value and the ranging error coefficient, as well as the thickness information of the light-transmitting material, can be established. Therefore, in practical applications, the corresponding ranging error coefficient and the thickness information of the light-transmitting material can be determined based on the received signal strength indication value. This allows for appropriate correction information to be obtained even when light is obstructed by light-transmitting materials of varying thicknesses, which helps improve the accuracy of the correction information and thus facilitates the determination of more accurate distance information.

[0009] Optionally, before searching for correction information corresponding to the received signal strength indication value in a preset relationship table, the method further includes: acquiring the channel impulse response collected by the UWB radar; determining a first interface and a second interface of the light-transmitting material based on the channel impulse response; the first interface being the interface where the radar signal enters the light-transmitting material from the air; the second interface being the interface where the radar signal enters the air from the light-transmitting material; determining the duration information of the radar signal penetrating the light-transmitting material based on the sampling point interval between the first interface and the second interface in the channel impulse response, and the sampling time interval of the channel impulse response; determining the backup thickness information of the light-transmitting material based on the duration information and a preset dielectric constant; and the step of searching for correction information corresponding to the received signal strength indication value in the preset relationship table includes: searching for thickness information in the preset relationship table whose deviation from the backup thickness information is not greater than a preset deviation value, and the ranging error coefficient corresponding to the thickness information, based on the received signal strength indication value. In this way, the backup thickness information can be determined through the channel impulse response, and then the corresponding thickness information can be searched in the preset relationship table in conjunction with the backup thickness information, which helps to improve the accuracy of the correction information.

[0010] Optionally, the correction information includes a ranging error value, and the preset relationship table is calibrated based on the following steps: obtaining a first received signal strength indication value of the sample object collected by the UWB radar under unobstructed conditions; obtaining the actual sample distance between the UWB radar and the sample object; obtaining a second received signal strength indication value and the measured sample distance of the same sample object collected by the UWB radar under conditions of light-transmitting material obstruction of different thicknesses and / or materials; wherein the transmitted signal strength corresponding to the first received signal strength indication value and the second received signal strength indication value is the same; for each second received signal strength indication value, according to the first received signal strength indication value... The method involves determining the difference in received signal intensity between the first received signal intensity indicator value and the second received signal intensity indicator value; for each second received signal intensity indicator value, determining the sample ranging error value based on the actual sample distance and the measured sample distance corresponding to the second received signal intensity indicator value; establishing a correspondence between the sample received signal intensity difference value and the ranging error value to obtain the preset relationship table; and determining correction information based on the received signal intensity indicator value includes: determining the difference in received signal intensity between the first received signal intensity indicator value and the second received signal intensity indicator value; and determining the corresponding ranging error value based on the difference in received signal intensity value.

[0011] Here, a correspondence can be established between the received signal strength difference and the ranging error value. This allows for a more accurate ranging error value to be obtained when the received signal strength difference is obtained under the current obstruction conditions. This improves the accuracy of the corrected distance and the clarity of the acquired image. Furthermore, the received signal strength difference reflects the attenuation introduced by the light-transmitting material, which is weakly correlated with the propagation distance, thus making it more versatile.

[0012] Optionally, before correcting the measured distance according to the correction information, the method further includes: acquiring the channel impulse response collected by the UWB radar; performing sparse reconstruction on the channel impulse response to determine the direct path between the UWB radar and the target object; and correcting the measured distance according to the correction information includes: correcting the measured distance of the direct path according to the correction information. In this way, using the distance corrected by the direct path to assist the camera in acquiring images can improve the accuracy of the focus position and, to a certain extent, improve the clarity of the acquired images.

[0013] Optionally, before acquiring the image of the target object based on the corrected distance, the method further includes: determining a magnification factor for the current acquisition area of ​​the target object when the target object is determined to be stationary; and acquiring the image of the target object based on the corrected distance includes: expanding the current acquisition area according to the magnification factor; and acquiring the image of the target object based on the expanded acquisition area and the corrected distance. Here, when acquiring the image of a stationary target object, a larger acquisition area can be used, which can improve the situation of focus failure or image blurring caused by the target object going out of the frame, thereby helping to improve image clarity.

[0014] Optionally, acquiring the image of the target object based on the corrected distance includes: continuously acquiring multiple frames of the target object's image based on the corrected distance; fusing the multiple frames of the target object's image; and determining the fused image as the target image of the target object. Here, fusing multiple frames of the target object's image to obtain the target image further improves the clarity of the acquired image to a certain extent.

[0015] Optionally, the light-transmitting material includes glass. This allows for a clearer image of the object in many scenarios where glass is used.

[0016] Secondly, embodiments of this application provide an image acquisition device, which includes an acquisition module, a determination module, a correction module, and an acquisition module. The acquisition module is used to acquire the received signal strength indication value of a target object acquired by a UWB radar under conditions of light-transmitting material obstruction, and the measured distance between the UWB radar and the target object; the determination module is used to determine correction information based on the received signal strength indication value; the correction module is used to correct the measured distance based on the correction information; and the acquisition module is used to acquire an image of the target object based on the corrected distance.

[0017] Thirdly, embodiments of this application provide an image acquisition system, comprising: a UWB radar, used to acquire a received signal strength indication value of a target object and a measured distance between the UWB radar and the target object when the light is obstructed by a light-transmitting material; a processor, used to acquire the received signal strength indication value of the target object acquired by the UWB radar when the light is obstructed by a light-transmitting material and the measured distance between the UWB radar and the target object; determine correction information based on the received signal strength indication value; correct the measured distance based on the correction information; and send the corrected distance to a camera; and a camera, used to acquire an image of the target object based on the corrected distance.

[0018] Fourthly, embodiments of this application provide an electronic device, including a processor and a memory, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the steps of the method provided in the first aspect above are performed.

[0019] Fifthly, embodiments of this application provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, performs the steps of the method provided in the first aspect above.

[0020] In a sixth aspect, embodiments of this application provide a computer program product comprising a computer program or instructions that, when executed by a processor, perform the method described in the first aspect.

[0021] Other features and advantages of this application will be set forth in the following description and will be apparent in part from the description or may be learned by practicing embodiments of this application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments of this application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 A flowchart illustrating an image acquisition method provided in this application embodiment;

[0024] Figure 2 A structural block diagram of an image acquisition device provided in an embodiment of this application;

[0025] Figure 3 A structural block diagram of an image acquisition system provided in an embodiment of this application;

[0026] Figure 4 This is a schematic diagram of the structure of an electronic device for performing an image acquisition method, provided in an embodiment of this application. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0028] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] It should be noted that, unless otherwise specified, the embodiments or technical features in the embodiments of this application may be combined.

[0030] In related technologies, when UWB radar detects the distance information of an object when it is obstructed by a light-transmitting material, the detected distance information is inaccurate due to the influence of the light-transmitting material. This results in a less clear image when image acquisition is based on this distance information. Specifically, this application considers that when UWB radar detects the distance information of an object through a light-transmitting material (such as glass), the material has a high relative permittivity for the UWB signal. During the penetration process, the UWB signal may be refracted, reflected, and attenuated, thus affecting the signal-to-noise ratio of the detected object. This indirectly affects the detection accuracy, causing the measured distance to be greater than the true distance. If the inaccurate distance information is used to assist the camera in autofocusing, the focus position will deviate from the true position of the object, resulting in a blurred and less sharp image, thus failing to obtain a clear image.

[0031] Therefore, to solve this problem, this application provides an image acquisition method, system, electronic device, storage medium, and program product. Furthermore, this application acquires the received signal strength indication value from a UWB radar under conditions of light-transmitting material obstruction, along with a potentially erroneous measured distance. Then, based on the acquired received signal strength indication value, correction information is determined to correct the measured distance. This reduces the error between the measured distance and the true distance, obtaining more accurate distance information. When this distance information is used to assist a camera in acquiring images, the deviation between the focus position and the actual position of the object can be reduced, resulting in a clearer image.

[0032] It should be noted that the defects in the solutions in the above-mentioned related technologies were discovered by the inventors after long-term practice and careful research. Therefore, the discovery process of the above-mentioned problems and the solutions proposed by the embodiments of the present invention in the following text should all be contributions made by the inventors to the present invention during the process of the present invention.

[0033] Furthermore, the image acquisition method provided in this application can be applied to a processor that can communicate with a UWB radar and a camera respectively, thereby obtaining the received signal strength indication value and the measured distance from the UWB radar, and after correcting the measured distance, sending the corrected distance information to the camera to assist the camera in acquiring images.

[0034] In addition, the processor may be installed on the UWB radar, or there may be no mechanical connection between the processor and the UWB radar; this application does not impose any restrictions on this.

[0035] Please see Figure 1 The diagram illustrates a flowchart of an image acquisition method provided in an embodiment of this application. Figure 1 As shown, the image acquisition method includes the following steps 101 to 104.

[0036] Step 101: Obtain the received signal strength indication value of the target object collected by the UWB radar under the condition of light-transmitting material obstruction, and the measured distance between the UWB radar and the target object;

[0037] The aforementioned light-transmitting materials can include, for example, glass, transparent plastic, or other materials that are substantially transparent to light. Thus, even if blocked by such a material, the UWB radar can still penetrate it and detect the distance information of the target object.

[0038] The aforementioned target objects may include, for example, people, animals, or other objects. In some applications, UWB radar can be used to detect the distance information of moving objects as well as stationary objects; there are no limitations on this.

[0039] The aforementioned Received Signal Strength Indicator (RSSI) value is a discrete value given by the UWB radar receiver after measuring and quantifying the power of the echo signal. It is used to characterize the strength of the signal reflected back by the target object.

[0040] The measured distances mentioned above are the distances to the target objects measured by UWB radar.

[0041] In some application scenarios, after obtaining the received signal strength indication value and the measured distance, the UWB radar can actively send both to the processor; in other application scenarios, the UWB radar can also send the obtained received signal strength indication value and the measured distance to the processor after receiving the acquisition request sent by the processor. This application does not impose any restrictions on this.

[0042] Step 102: Determine correction information based on the received signal strength indication value;

[0043] The aforementioned correction information can be considered as information used to correct the measured distance. It could be, for example, the ranging error value caused by the light-transmitting material, or information related to that ranging error value (such as the thickness of the light-transmitting material, the ranging error coefficient per unit thickness of glass, etc.), and there are no restrictions here.

[0044] Here, the received signal strength indication value reflects the path loss of the UWB radar signal during propagation. When the light-transmitting material blocks the signal, there is a correlation between this path loss and the ranging error. Therefore, the received signal strength indication value can be used to determine the correction information that can be used to correct the measured distance.

[0045] Step 103: Correct the measured distance according to the correction information;

[0046] In some applications, if the correction information is a ranging error value, the corrected distance can be obtained by subtracting this ranging error value from the measured distance. This process can be represented by, for example, the following formula: ;in, Characterizing the corrected distance, Characterizing the measured distance, Characterizes the distance measurement error value.

[0047] In other application scenarios, if the correction information is related to the ranging error value, the ranging error value can be determined first using this relevant information, and then the corrected information can be obtained by subtracting the ranging error value from the measured distance.

[0048] In these application scenarios, if the correction information includes the thickness of the light-transmitting material and the ranging error coefficient caused by each unit thickness of the light-transmitting material, the corrected distance can be determined, for example, by the following formula: ;in, Characterizing the corrected distance, Characterizing the measured distance, The distance measurement error coefficient characterizing the amount of light-transmitting material per unit thickness. Characterizes the thickness of a light-transmitting material.

[0049] Step 104: Based on the corrected distance, acquire an image of the target object.

[0050] Here, the processor can send an acquisition command to the camera, carrying the corrected distance in the acquisition command, so that the camera can acquire an image of the target object based on the corrected distance.

[0051] In this implementation, when a target object is obscured by a translucent material, correction information can be determined based on the received signal strength indication value acquired by the UWB radar. This correction information is then used to correct the measured distance, thereby reducing the error between the measured distance and the true distance and obtaining more accurate distance information. When this distance information is used to assist the camera in acquiring images, the deviation between the focus position and the true position of the object can be reduced, resulting in a clearer image.

[0052] In some alternative implementations, the processor can, for example, input the received signal indication value into a pre-trained model (e.g., random forest, support vector machine, etc.) and use the model to output correction information. In these implementations, the aforementioned model can, for example, be trained with different sample received signal indication values ​​as input and the true correction information corresponding to each sample received signal indication value as the desired output.

[0053] In some alternative implementations, the processor can look up correction information corresponding to the received signal strength indication value in a preset relationship table; the preset relationship table stores the correspondence between the received signal strength indication value and the correction information. This is more convenient and faster.

[0054] In some application scenarios, the correction information includes the thickness information of the light-transmitting material and the ranging error coefficient caused by the light-transmitting material per unit thickness; here, if we take... The coefficient characterizing the ranging error is then... This can characterize that each millimeter of light-transmitting material introduces a ranging error of 0.3 centimeters.

[0055] Thus, the preset relationship table can be defined based on the following steps:

[0056] Step A1: Obtain the sample received signal intensity indication value of the sample object and the measured sample distance between the sample object and the UWB radar under the condition of sample light-transmitting material with different thicknesses being blocked by the UWB radar;

[0057] It should be noted that the implementation process of step A1 above can be similar to the implementation process of step 101 above, and will not be repeated here.

[0058] Step A2: Obtain the true distance between the UWB radar and the sample object;

[0059] The aforementioned true distance to the sample is the actual distance between the UWB radar and the sample object in a real-world scenario. This distance can be obtained, for example, by measuring with a tape measure. For instance, an operator can directly measure the actual distance between the UWB radar and the sample object using a tape measure, and then input this actual distance into the processor, thus allowing the processor to obtain the true distance to the sample.

[0060] Step A3: Obtain the thickness information corresponding to the light-transmitting material of the samples with different thicknesses;

[0061] In some applications, this thickness information can also be input into the processor by the operator, and it can include, for example, a thickness in the range of 5 mm to 20 mm.

[0062] Step A4: For each of the sample received signal intensity indication values, determine the sample ranging error coefficient corresponding to the sample received signal intensity indication value based on the thickness information of the light-transmitting material of the sample when the sample received signal intensity indication value is obtained, the measured distance of the sample, and the true distance of the sample.

[0063] For example, calculation formulas can be used. Determine the sample ranging error coefficient. Among them, Characterizing the true distance of the sample, Characterizing the measured distance of the sample, The coefficient of error in sample ranging caused by the light-transmitting material per unit thickness of the sample. This characterizes the thickness of the light-transmitting material in the current sample. Thus, only... Since it is an unknown, we can obtain The specific value.

[0064] Therefore, for each sample received signal strength indication value, a unique corresponding sample ranging error coefficient can be obtained.

[0065] Step A5: Establish the correspondence between the sample received signal strength indication value, the sample ranging error coefficient, and the thickness information to obtain the preset relationship table.

[0066] In this implementation, the correspondence between the received signal strength indication value and the ranging error coefficient, as well as the thickness information of the light-transmitting material, can be calibrated. Therefore, in practical applications, the corresponding ranging error coefficient and the thickness information of the light-transmitting material can be determined based on the received signal strength indication value. This allows for appropriate correction information to be obtained even when light is obstructed by light-transmitting materials of varying thicknesses, which helps improve the accuracy of the correction information and thus facilitates the determination of more accurate distance information.

[0067] Furthermore, before the processor searches for the correction information corresponding to the received signal strength indication value in the preset relationship table, it may first perform the following steps:

[0068] Step 1: Obtain the channel impulse response collected by the UWB radar;

[0069] The aforementioned channel impulse response (CIR) is used in some applications by UWB radar to estimate the CIR by transmitting a known signal and then comparing the received signal with the original transmitted signal. The UWB radar can then send the estimated CIR to a processor.

[0070] Step 2: Based on the channel impulse response, determine the first interface and the second interface of the light-transmitting material; the first interface is the interface through which the radar signal enters the light-transmitting material from the air; the second interface is the interface through which the radar signal enters the air from the light-transmitting material.

[0071] In some applications, CIR can be represented as a discrete sequence. Where n represents the index of the discrete sequence, the discrete sequence can then be filtered and normalized to obtain... Then, you can The above method detects all local maxima points that satisfy the following conditions, thus obtaining candidate peak points; where condition 1 is... The amplitude is greater than a preset threshold, which can be, for example, 3 times the RMS value (Root Mean Square, or RMS value); Condition 2 is to satisfy the waveform characteristics of the interface reflection, that is, the rising edge is steep and the falling edge is gentle.

[0072] In some application scenarios, for each detected candidate peak point, the rising edge slope and falling edge slope are calculated separately, and then the asymmetry characteristics of each candidate peak point are determined based on these two factors. The rising edge slope of the candidate peak point can be calculated using the following formula: ;in, Characterizes the slope of the rising edge; Characterizes the number of sample points considered when calculating the rising edge slope; it determines how many sample points to the left of the peak point p will be used to calculate the rising edge slope. Characterizes the signal value at the candidate peak point p. The signal value at the i-th position to the left of the candidate peak point p is represented by the following formula: As the value of i increases, the signal value is gradually shifted to the left to examine earlier signal values. Then, the falling edge slope of the candidate peak point can be calculated according to the following formula: ;in, Characterizes the slope of the falling edge; Characterizes the number of sample points considered when calculating the falling edge slope, which is used to determine how many sample points to the right of the peak point p will be used to calculate the falling edge slope; The signal value at the i-th position to the right of the candidate peak point p is represented by this value. As the value of i increases, the signal is gradually shifted to the right to examine later signal values. Then, the ratio of the rising edge slope to the falling edge slope can be used... Used to characterize asymmetric features. That is, .

[0073] Here, for example, it can also be determined through asymmetric features. Does condition 2 above meet? Specifically, for example, it can be... When the value is greater than the preset value, it is determined that condition 2 is met. The preset value can be, for example, 2 or 3.

[0074] Then, you can Centered on any candidate peak point, calculate the peak value of the data within a window of length M (e.g., M = 21 sampling points). This peak can be used to measure the sharpness of the waveform in its vicinity. For example, the mean of the data within the window can be calculated. and standard deviation Then it can be calculated using the formula The peak value was obtained.

[0075] Then, we can determine whether it is satisfied. and ;in, The threshold for determining the ratio of the rising edge slope to the falling edge slope can be, for example, 2.5. The threshold for determining the peak value can be, for example, 3.5.

[0076] Then, among the candidate peak points that meet the judgment criteria, the interface corresponding to the peak point with the earliest occurrence time can be determined as the first interface, and the interface corresponding to the peak point with the latest occurrence time can be determined as the second interface. It is understandable that, since radar signals can penetrate light-transmitting materials, both the earliest and latest peak points should exist.

[0077] Step 3: Determine the duration of radar signal penetration of the light-transmitting material based on the sampling point interval between the first interface and the second interface in the channel impulse response, and the sampling time interval of the channel impulse response.

[0078] Specifically, the duration information can be determined, for example, by the following calculation formula: ;in, Characterizes the duration information; Characterizes the peak point corresponding to the second interface; Characterizes the peak point corresponding to the first interface; The sampling time interval characterizes the CIR.

[0079] Step 4: Determine the backup thickness information of the light-transmitting material based on the duration information and the preset dielectric constant;

[0080] Specifically, for example, the spare thickness information can be determined using the following formula: ;in, Characterizes the spare thickness information; Characterizes the speed of light in a vacuum; The preset dielectric constant can be, for example, 6.8.

[0081] Thus, when the processor searches for correction information corresponding to the received signal strength indication value in the preset relationship table, it can find, based on the received signal strength indication value, thickness information whose deviation from the backup thickness information is not greater than a preset deviation value, and the ranging error coefficient corresponding to that thickness information. The aforementioned deviation value can be, for example, 0.2mm, 0.3mm, or similar values.

[0082] In this implementation, the backup thickness information can be determined by CIR, and then the corresponding thickness information can be found in a preset relationship table in combination with the backup thickness information, which helps to improve the accuracy of the correction information.

[0083] It should be noted that if no thickness information with a deviation no greater than a preset deviation value is found in the preset relationship table, the spare thickness information can be used to determine correction information, which is then the ranging error value. Specifically, this ranging error value can be determined using a calculation formula: ;in, This represents the ranging error value; the meanings of the other parameters are the same as those mentioned above.

[0084] In other application scenarios, the correction information includes ranging error values, so the preset relationship table can also be calibrated based on the following steps:

[0085] Step B1: Obtain the first received signal strength indication value of the sample object collected by the UWB radar under unobstructed conditions;

[0086] Step B2: Obtain the true distance between the UWB radar and the sample object;

[0087] Step B3: Obtain the second received signal strength indication value and the measured distance of the sample object collected by the UWB radar under the condition of light-transmitting material with different thicknesses and / or materials; wherein the transmitted signal strength corresponding to the first received signal strength indication value and the second received signal strength indication value is the same;

[0088] It should be noted that the implementation process of steps B1 to B3 is similar to the process of obtaining the received signal strength indication value, the true distance of the sample, and the measured distance described above, and will not be repeated here.

[0089] In addition, during the process of acquiring the first and second received signal strength indication values, only the light-transmitting material changes. Other factors, such as the acquisition attitude of the UWB radar and the position of the sample object, remain unchanged to ensure the reliability of the calibration.

[0090] Step B4: For each second received signal strength indication value, determine the sample received signal strength difference value between the two based on the first received signal strength indication value and the second received signal strength indication value.

[0091] For example, the difference between the first received signal strength indication value and the second received signal strength indication value can be obtained to obtain the difference value of the sample received signal strength between the two.

[0092] Step B5: For each second received signal strength indication value, determine the sample ranging error value based on the true distance of the sample and the actual measured distance of the sample corresponding to the second received signal strength indication value.

[0093] For example, the difference between the measured distance of the sample and the true distance of the sample can be used to obtain the sample distance measurement error value between the two.

[0094] Step B6: Establish the correspondence between the difference in the received signal intensity of the sample and the ranging error value to obtain the preset relationship table.

[0095] Thus, determining the correction information based on the received signal strength indication value in step 102 above can include:

[0096] First, determine the difference in received signal strength between the received signal strength indication value and the first received signal strength indication value; then, determine the corresponding ranging error value based on the difference in received signal strength.

[0097] For example, the difference between the received signal strength indication value and the first received signal strength indication value can be calculated, and then the corresponding ranging error value can be looked up in a preset relationship table based on this difference. Then, the ranging error value can be used to correct the measured distance to obtain the corrected distance.

[0098] In this implementation, a correspondence can be established between the received signal strength difference value and the ranging error value. This allows for a more accurate ranging error value to be obtained when the received signal strength difference value is obtained under the current obstruction conditions. This improves the accuracy of the corrected distance and enhances the clarity of the acquired image. Furthermore, the received signal strength difference value reflects the attenuation introduced by the light-transmitting material, which is weakly correlated with the propagation distance, thus making it more versatile.

[0099] It should be noted that when calibrating the aforementioned preset relationship table, in addition to the calibration items mentioned above (such as thickness information and material information), environmental factors during calibration (such as temperature and humidity) and the angle of incidence (which can be the angle between the current beam direction of the UWB radar and the calibration beam direction when the light-transmitting material is perpendicularly incident) can also be determined to improve the accuracy of the correction information. In practical applications, if the angle of incidence is large, the actual penetration path of the radar signal in the light-transmitting material is usually longer; if the temperature and humidity are high, the actual penetration path of the radar signal in the light-transmitting material is usually also longer; therefore, these factors may cause the distance information collected by the UWB radar to be greater than the actual distance information. Therefore, when calibrating the preset relationship table, further considering the angle of incidence and / or environmental factors can further improve the accuracy of the correction information.

[0100] It should be noted that if the above-mentioned incident angle factors and / or environmental factors are taken into account, when determining the correction information corresponding to the target object, the corresponding incident angle and environmental information can be obtained at the same time, so as to determine more suitable correction information to correct the distance error caused by the incident angle and / or environmental factors and improve the accuracy of the corrected distance.

[0101] In some applications, considering that light-transmitting materials may cause multipath effects, the path errors caused by multipath effects can be eliminated first. The multipath effect can be understood as follows: during the process of UWB radar signals traveling from the transmitter to the receiver, in addition to the direct path, they also reach the receiver through other paths (reflection, refraction, diffraction, scattering, etc.), resulting in the UWB radar receiving multiple copies of signals with different time delays, phases, and amplitudes.

[0102] Therefore, in some alternative implementations, before correcting the measured distance based on the correction information as described in step 103 above, the processor may also acquire the channel impulse response collected by the UWB radar; and perform sparse reconstruction on the channel impulse response to determine the direct path between the UWB radar and the target object.

[0103] Similarly, UWB radar can estimate the channel impulse response by transmitting a known signal and then comparing the difference between the received signal and the original transmitted signal.

[0104] After the UWB radar estimates the channel impulse response, it can send it to the processor, which can then perform sparse reconstruction to determine the direct path between the UWB radar and the target object.

[0105] In some application scenarios, such as the Orthogonal Matching Pursuit (OMP) algorithm, the channel impulse response of UWB signals can be sparsely reconstructed to achieve accurate separation of the signals in the direct path and the reflected path.

[0106] Thus, the step 103 above, which involves correcting the measured distance based on the correction information, may include: correcting the measured distance of the direct path based on the correction information.

[0107] In this implementation, a direct path can be determined, and then the measured distance of this direct path can be corrected to obtain the corrected distance. Using this corrected distance to assist the camera in acquiring images can improve the accuracy of the focus position and, to some extent, enhance the clarity of the acquired images.

[0108] In some alternative implementations, before acquiring the image of the target object based on the corrected distance as described in step 104 above, the processor may also determine the area magnification factor of the current acquisition area of ​​the target object if the target object is determined to be stationary.

[0109] In some application scenarios, the processor can obtain multiple measured distances of the target object within a preset time period (e.g., 100 milliseconds), and then determine the standard deviation of these measured distances. If the standard deviation is less than the preset standard deviation threshold (e.g., 0.03 meters), the target object can be regarded as being in a stationary state.

[0110] In other application scenarios, the processor can also determine whether the difference between multiple consecutive measured distances is less than a preset difference threshold. If it is less, the target object can be regarded as being in a stationary state.

[0111] In these application scenarios, for example, velocity information and / or the positional change of the same feature point across multiple consecutive frames can be further combined to determine whether the target object is stationary. For instance, in addition to meeting the aforementioned conditions for being stationary, it can be further specified that the target object is stationary only if both of the following conditions are met: the target object's velocity is less than a preset velocity threshold, and the positional change of the same feature point is less than a preset positional change threshold (e.g., one pixel). This improves the accuracy of determining the target object's state.

[0112] The aforementioned current acquisition area can be the image acquisition area sent by the camera to the processor. Then, if the processor determines that the target object is in a stationary state, it can determine the area magnification factor corresponding to the current acquisition area.

[0113] In some applications, the area magnification factor can be an empirical value, such as 1.5 or 2. In other applications, the area magnification factor can be determined by referencing the object distance (the distance between the target object and the camera lens) and the camera's focal length setting. The area magnification factor can be positively correlated with the object distance and negatively correlated with the focal length, ensuring that the pixel percentage of the target object within the acquisition area is not too low.

[0114] Thus, the step 104 above, which involves acquiring an image of the target object based on the corrected distance, may include: expanding the current acquisition area according to the area magnification factor; and acquiring an image of the target object based on the expanded acquisition area and the corrected distance.

[0115] Understandably, the processor can send the area magnification factor corresponding to the current acquisition area to the camera, so that the camera can expand the current acquisition area according to the area magnification factor, thereby acquiring image information over a larger area.

[0116] In this implementation, when acquiring images of stationary target objects, a larger acquisition area can be captured. This can improve the situation where the focus fails or the image is blurred due to the target object going out of the frame, thereby helping to improve the image clarity.

[0117] In some alternative implementations, the acquisition of the image of the target object based on the corrected distance described in step 104 above may include the following sub-steps:

[0118] Sub-step 1041: Based on the corrected distance, continuously acquire multiple frames of images of the target object;

[0119] Sub-step 1042: Fuse multiple frames of the target object image;

[0120] In some application scenarios, fusion can be achieved through calculations such as the following formula: ,and ;in, Pixel coordinates representing the fused image; Characterizes the number of image frames to be fused. Characterizes the image index; The pixel coordinates representing the images to be fused; The weights can be empirical values; in addition, the weights of each image to be fused can be the same or different, and this application does not impose any restrictions on this.

[0121] Sub-step 1043: Determine the fused image as the target image of the target object.

[0122] It should be noted that the above sub-steps 1041 to 1043 may be executed by the processor through the same instruction to the camera, or the processor may execute by the processor through multiple instructions to the camera respectively. This application does not limit this.

[0123] In this implementation, multiple frames of target object images can be fused to obtain the target image, which further improves the clarity of the acquired image to a certain extent.

[0124] In some applications, the light-transmitting material may include glass.

[0125] It is understandable that glass is often used for exhibitions in many scenarios, such as museum exhibits and jewelry stores displaying jewelry. Therefore, the image acquisition method mentioned above can obtain relatively clear object images in many scenarios where glass is used.

[0126] Those skilled in the art will understand that, in the methods described in the specific embodiments, the order in which the steps are written does not imply a strict execution order and does not constitute any limitation on the implementation process. The specific execution order of each step should be determined by its function and possible internal logic.

[0127] Please see Figure 2The diagram illustrates a structural block diagram of an image acquisition device according to an embodiment of this application. This image acquisition device can be a module, program segment, or code on an electronic device. It should be understood that this device is similar to the one described above. Figure 1 The method implementation corresponds to this and can be executed. Figure 1 The various steps involved in the method implementation examples.

[0128] Optionally, the image acquisition device includes an acquisition module 201, a determination module 202, a correction module 203, and an acquisition module 204. The acquisition module 201 is used to acquire the received signal strength indication value of the target object acquired by the UWB radar under the condition of light-transmitting material obstruction, and the measured distance between the UWB radar and the target object; the determination module 202 is used to determine correction information based on the received signal strength indication value; the correction module 203 is used to correct the measured distance based on the correction information; and the acquisition module 204 is used to acquire an image of the target object based on the corrected distance.

[0129] Optionally, the determining module 202 is further configured to: search for correction information corresponding to the received signal strength indication value in a preset relationship table; the preset relationship table stores the correspondence between the received signal strength indication value and the correction information.

[0130] Optionally, the correction information includes the thickness information of the light-transmitting material, the ranging error coefficient caused by the light-transmitting material per unit thickness; and the preset relationship table is calibrated based on the following steps: obtaining the sample received signal intensity indication value of the sample object collected by the UWB radar under the condition of sample light-transmitting material obstruction of different thicknesses, and the actual sample distance between the sample object and the UWB radar; obtaining the actual sample distance between the UWB radar and the sample object; obtaining the thickness information corresponding to the sample light-transmitting material of different thicknesses respectively; for each sample received signal intensity indication value, determining the sample ranging error coefficient corresponding to the sample received signal intensity indication value based on the thickness information of the sample light-transmitting material when the sample received signal intensity indication value is obtained, the actual sample distance, and the actual sample distance; establishing the correspondence between the sample received signal intensity indication value, the sample ranging error coefficient, and the thickness information to obtain the preset relationship table.

[0131] The device further includes a backup module, which is configured to: acquire the channel impulse response collected by the UWB radar before searching for correction information corresponding to the received signal strength indication value in a preset relationship table; determine the first interface and the second interface of the light-transmitting material based on the channel impulse response; the first interface is the interface where the radar signal enters the light-transmitting material from the air; the second interface is the interface where the radar signal enters the air from the light-transmitting material; determine the duration information of the radar signal penetrating the light-transmitting material based on the sampling point interval between the first interface and the second interface in the channel impulse response and the sampling time interval of the channel impulse response; determine the backup thickness information of the light-transmitting material based on the duration information and a preset dielectric constant; and the determining module 202 is further configured to: search for thickness information in the preset relationship table whose deviation from the backup thickness information is not greater than a preset deviation value, and the ranging error coefficient corresponding to the thickness information, based on the received signal strength indication value.

[0132] Optionally, the correction information includes a ranging error value, and the preset relationship table is calibrated based on the following steps: obtaining a first received signal strength indication value of the sample object collected by the UWB radar under unobstructed conditions; obtaining the actual sample distance between the UWB radar and the sample object; obtaining a second received signal strength indication value and the measured sample distance of the same sample object collected by the UWB radar under conditions of light-transmitting material obstruction of different thicknesses and / or materials; wherein the transmitted signal strength corresponding to the first received signal strength indication value and the second received signal strength indication value is the same; for each second received signal strength indication value, according to the first received signal strength indication value... The method involves determining the difference in received signal intensity between the first received signal intensity indicator value and the second received signal intensity indicator value; for each second received signal intensity indicator value, determining the sample ranging error value based on the actual sample distance and the measured sample distance corresponding to the second received signal intensity indicator value; establishing a correspondence between the sample received signal intensity difference value and the ranging error value to obtain the preset relationship table; and determining correction information based on the received signal intensity indicator value includes: determining the difference in received signal intensity between the first received signal intensity indicator value and the second received signal intensity indicator value; and determining the corresponding ranging error value based on the difference in received signal intensity value.

[0133] Optionally, the device further includes a separation module, which is configured to: acquire the channel impulse response collected by the UWB radar before correcting the measured distance according to the correction information; perform sparse reconstruction on the channel impulse response to determine the direct path between the UWB radar and the target object; and the correction module 203 is further configured to: correct the measured distance of the direct path according to the correction information.

[0134] Optionally, the device further includes an enlargement module, which is configured to: before acquiring an image of the target object based on the corrected distance, determine an area enlargement factor for the current acquisition area of ​​the target object, provided that the target object is stationary; and the acquisition module 204 is further configured to: enlarge the current acquisition area according to the area enlargement factor; and acquire an image of the target object based on the enlarged acquisition area and the corrected distance.

[0135] Optionally, the acquisition module 204 is further configured to: continuously acquire multiple frames of images of the target object based on the corrected distance; fuse the multiple frames of images of the target object; and determine the fused image as the target image of the target object.

[0136] Optionally, the light-transmitting material includes glass.

[0137] It should be noted that those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the device described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0138] Based on the same inventive concept, this application provides an image acquisition system. Please continue reading. Figure 3 This diagram illustrates a structural block diagram of an image acquisition system provided in an embodiment of this application. Figure 3 As shown, the image acquisition system includes a UWB radar 301, a processor 302, and a camera 303. The UWB radar 301 is used to acquire the received signal strength indication value of the target object and the measured distance between the UWB radar 301 and the target object when the light is obstructed by a transparent material. The processor 302 is used to acquire the received signal strength indication value of the target object acquired by the UWB radar 301 when the light is obstructed by a transparent material, and the measured distance between the UWB radar 301 and the target object; determine correction information based on the received signal strength indication value; correct the measured distance based on the correction information; and send the corrected distance to the camera 303. The camera 303 is used to acquire an image of the target object based on the corrected distance.

[0139] It should be noted that those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0140] Please see Figure 4 , Figure 4 This is a schematic diagram of an electronic device for performing an image acquisition method, provided in an embodiment of this application. The electronic device may include: at least one processor 401, such as a CPU; at least one communication interface 402; at least one memory 403; and at least one communication bus 404. The communication bus 404 is used to enable direct communication between these components. In this embodiment, the communication interface 402 is used for signaling or data communication with other node devices. The memory 403 may be a high-speed RAM or a non-volatile memory, such as at least one disk storage device. Optionally, the memory 403 may also be at least one storage device located remotely from the aforementioned processor. The memory 403 stores computer-readable instructions. When these computer-readable instructions are executed by the processor 401, the electronic device can perform the methods provided in the above-described method embodiments.

[0141] Understandable. Figure 4 The structure shown is for illustrative purposes only; the electronic device may also include components that are more advanced than those shown. Figure 4 The more or fewer components shown, or having the same Figure 4 The different configurations shown. Figure 4 The components shown can be implemented using hardware, software, or a combination thereof.

[0142] This application provides a computer-readable storage medium storing a computer program thereon. When the computer program is executed by a processor, it can perform the methods provided in the above-described method embodiments.

[0143] This application provides a computer program product, which includes a computer program stored on a non-transitory computer-readable storage medium. The computer program includes program instructions, and when the program instructions are executed by a computer, the computer can perform the methods provided in the above-described method embodiments.

[0144] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0145] Furthermore, the units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0146] Furthermore, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0147] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. An image acquisition method, characterized in that, include: The received signal strength indication value of the target object collected by the UWB radar under the condition of light-transmitting material obstruction is obtained, as well as the measured distance between the UWB radar and the target object; Based on the received signal strength indication value, determine the correction information; The measured distance is corrected based on the correction information; Based on the corrected distance, an image of the target object is acquired; The step of determining the correction information based on the received signal strength indication value includes: The correction information corresponding to the received signal strength indication value is searched in a preset relationship table; the preset relationship table stores the correspondence between the received signal strength indication value and the correction information. The correction information includes the thickness information of the light-transmitting material, the ranging error coefficient caused by the light-transmitting material per unit thickness; and The preset relationship table is defined based on the following steps: The UWB radar acquires the sample received signal intensity indication value of the sample object under the condition of sample light-transmitting material with different thicknesses, and the actual measured distance between the sample object and the UWB radar. Obtain the true distance between the UWB radar and the sample object; Obtain the thickness information corresponding to the light-transmitting materials of the samples with different thicknesses; For each of the sample received signal intensity indication values, the sample ranging error coefficient corresponding to the sample received signal intensity indication value is determined based on the thickness information of the light-transmitting material of the sample when the sample received signal intensity indication value is obtained, the measured distance of the sample, and the actual distance of the sample. Establish the correspondence between the sample received signal intensity indication value, the sample ranging error coefficient, and the thickness information to obtain the preset relationship table.

2. The method according to claim 1, characterized in that, Before searching for correction information corresponding to the received signal strength indication value in a preset relationship table, the method further includes: Obtain the channel impulse response acquired by the UWB radar; Based on the channel impulse response, the first interface and the second interface of the light-transmitting material are determined; the first interface is the interface through which the radar signal enters the light-transmitting material from the air; the second interface is the interface through which the radar signal enters the air from the light-transmitting material. Based on the sampling point interval between the first interface and the second interface in the channel impulse response, and the sampling time interval of the channel impulse response, the duration information of the radar signal penetrating the light-transmitting material is determined. Based on the duration information and the preset dielectric constant, the backup thickness information of the light-transmitting material is determined; and The step of searching for correction information corresponding to the received signal strength indication value in a preset relationship table includes: Based on the received signal strength indication value, the thickness information whose deviation from the backup thickness information is not greater than a preset deviation value is found in the preset relationship table, along with the ranging error coefficient corresponding to the thickness information.

3. The method according to claim 1, characterized in that, The correction information includes the ranging error value, and The preset relationship table is also defined based on the following steps: Obtain the first received signal strength indication value of the sample object collected by the UWB radar under unobstructed conditions; Obtain the true distance between the UWB radar and the sample object; The second received signal strength indication value and the measured distance of the sample object are obtained by the UWB radar under the condition of light-transmitting material with different thicknesses and / or materials; wherein the transmitted signal strength corresponding to the first received signal strength indication value and the second received signal strength indication value is the same; For each second received signal strength indication value, the difference in sample received signal strength between the two is determined based on the first received signal strength indication value and the second received signal strength indication value. For each second received signal strength indication value, the sample ranging error value is determined based on the actual distance of the sample and the measured distance of the sample corresponding to the second received signal strength indication value. Establish the correspondence between the difference in received signal intensity of the sample and the ranging error value to obtain the preset relationship table; and The step of determining the correction information based on the received signal strength indication value includes: Determine the difference in received signal strength between the received signal strength indication value and the first received signal strength indication value; The corresponding ranging error value is determined based on the difference in received signal strength.

4. The method according to claim 1, characterized in that, Before correcting the measured distance based on the correction information, the method further includes: Obtain the channel impulse response acquired by the UWB radar; Sparse reconstruction of the channel impulse response determines the direct path between the UWB radar and the target object; and The step of correcting the measured distance based on the correction information includes: The measured distance of the direct route is corrected based on the correction information.

5. The method according to claim 1, characterized in that, Before acquiring the image of the target object based on the corrected distance, the method further includes: Given that the target object is determined to be stationary, determine the area magnification factor of the current acquisition area of ​​the target object; and The process of acquiring an image of the target object based on the corrected distance includes: The current collection area is expanded according to the area expansion factor; Based on the expanded acquisition area and the corrected distance, an image of the target object is acquired.

6. The method according to claim 1, characterized in that, The process of acquiring an image of the target object based on the corrected distance includes: Based on the corrected distance, multiple frames of images of the target object are continuously acquired; Fuse multiple frames of the target object image; The fused image is determined as the target image of the target object.

7. The method according to any one of claims 1-6, characterized in that, The light-transmitting material includes glass.

8. An image acquisition system, characterized in that, include: UWB radar is used to collect the received signal strength indication value of a target object and the measured distance between the UWB radar and the target object when the light-transmitting material is blocked. The processor is used to acquire the received signal strength indication value of the target object collected by the UWB radar under the condition of light-transmitting material obstruction, and the measured distance between the UWB radar and the target object; and to determine correction information based on the received signal strength indication value. Based on the correction information, the measured distance is corrected; the corrected distance is sent to the camera; A camera, used to acquire an image of the target object based on a corrected distance; The processor is specifically used to look up correction information corresponding to the received signal strength indication value in a preset relationship table; the preset relationship table stores the correspondence between the received signal strength indication value and the correction information; The correction information includes the thickness information of the light-transmitting material and the ranging error coefficient caused by the light-transmitting material per unit thickness; and the processor is specifically used for: The UWB radar acquires the sample received signal intensity indication value of the sample object under the condition of sample light-transmitting material with different thicknesses, and the actual measured distance between the sample object and the UWB radar. Obtain the true distance between the UWB radar and the sample object; Obtain the thickness information corresponding to the light-transmitting materials of the samples with different thicknesses; For each of the sample received signal intensity indication values, the sample ranging error coefficient corresponding to the sample received signal intensity indication value is determined based on the thickness information of the light-transmitting material of the sample when the sample received signal intensity indication value is obtained, the measured distance of the sample, and the actual distance of the sample. Establish the correspondence between the sample received signal intensity indication value, the sample ranging error coefficient, and the thickness information to obtain the preset relationship table.

9. An electronic device, characterized in that, It includes a processor and a memory, the memory storing computer-readable instructions that, when executed by the processor, perform the method as described in any one of claims 1-7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it performs the method as described in any one of claims 1-7.

11. A computer program product, comprising a computer program or instructions, characterized in that, When the computer program or instructions are executed by the processor, they perform the method as described in any one of claims 1-7.

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