Liquid contraband volume measurement method based on X-ray image

Abstract

The invention provides a liquid contraband volume measurement method based on an X-ray image, and the method comprises the steps: determining a target liquid type of a to-be-detected liquid based on an X-ray image under a condition that the to-be-detected liquid exists in a to-be-detected package based on the X-ray image of the to-be-detected package; under the condition that the to-be-detected liquid is determined to be a liquid contraband based on the target liquid type, determining an actual height distance in the height direction represented by each pixel point corresponding to the to-be-detected liquid in an X-ray image; and determining the volume of the liquid to be detected based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction and the actual vertical distance represented by each pixel point in the vertical direction. According to the invention, the volume of the liquid stored in the container can be accurately determined, and the safety of security check is improved.

Description

Technical Field

[0001] The invention relates to the technical field of security inspection, and in particular to a method for measuring the volume of liquid contraband based on X-ray images. Background Art

[0002] For the reliable protection of public safety, in some special occasions, such as meetings with large gatherings of people, and some specific scenarios, such as traveling by rail transportation such as subways and high-speed railways, or by civil aviation such as airplanes, it is necessary to conduct security checks on various items carried by passengers.

[0003] When testing a container filled with liquid, it is usually necessary to place the container filled with liquid on a dedicated liquid detection instrument to determine whether the container contains liquid contraband, such as sulfuric acid, alcohol, gasoline, etc. However, the existing liquid detection instrument cannot effectively measure the specific volume of the liquid stored in the container, so even if it is determined that there is liquid contraband in the container, it is impossible to estimate its harmfulness based on the specific properties and magnitude of the liquid contraband, so that there are still certain safety hazards to public safety. Summary of the invention

[0004] The present invention provides a method for measuring the volume of liquid contraband based on X-ray images, which is used to solve the defect in the prior art that the specific volume of the liquid stored in the container cannot be determined, resulting in low security of security inspection, and can accurately determine the volume of the liquid stored in the container, thereby improving the security of security inspection.

[0005] The present invention provides a method for measuring the volume of liquid contraband based on X-ray images, comprising: In a case where it is determined based on the X-ray image including the package to be inspected that the package to be inspected contains a liquid to be inspected, determining a target liquid type of the liquid to be inspected based on the X-ray image; In the case where the liquid to be detected is determined to be a liquid contraband based on the target liquid type, determining an actual height distance in the height direction represented by each pixel point corresponding to the liquid to be detected in the X-ray image; The volume of the liquid to be detected is determined based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction, and the actual vertical distance represented by each pixel point in the vertical direction.

[0006] According to a method for measuring the volume of liquid contraband based on X-ray images provided by the present invention, the actual height distance represented by each pixel point corresponding to the liquid to be detected in the X-ray image in the height direction is determined, including: For each pixel point corresponding to the liquid to be detected in the X-ray image, obtaining an initial high-energy X-ray intensity of the pixel point in a high-energy sub-image corresponding to the liquid to be detected, and an attenuated high-energy X-ray intensity of the pixel point; Acquire the initial low-energy X-ray intensity of the pixel point in the low-energy sub-image corresponding to the liquid to be detected, and the attenuated low-energy X-ray intensity of the pixel point; Based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity and the attenuated low-energy X-ray intensity, an actual height distance in the height direction represented by the pixel point is determined.

[0007] According to a method for measuring the volume of liquid contraband based on X-ray images provided by the present invention, the actual height distance represented by the pixel point in the height direction is determined based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, and the attenuated low-energy X-ray intensity, including: Based on the correspondence between the liquid type, the X-ray energy value and the medium attenuation coefficient, determine a first medium attenuation coefficient corresponding to the target liquid type under a high X-ray energy value, and a second medium attenuation coefficient corresponding to the target liquid type under a low X-ray energy value; Based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, the attenuated low-energy X-ray intensity, the first medium attenuation coefficient and the second medium attenuation coefficient, the actual height distance represented by the pixel point in the height direction is determined.

[0008] According to a method for measuring the volume of liquid contraband based on X-ray images provided by the present invention, the actual height distance represented by the pixel point in the height direction is determined based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, the attenuated low-energy X-ray intensity, the first medium attenuation coefficient, and the second medium attenuation coefficient, including: The actual height distance represented by the pixel point in the height direction is determined based on formula (1): (1)

[0009] in, Represents pixel The actual height distance represented in the height direction, represents the attenuation coefficient of the first medium, represents the attenuation coefficient of the second medium, Represents the pixel point in the low-energy sub-image The initial low-energy X-ray intensity at Represents the pixel point in the low-energy sub-image The intensity of low-energy X-rays after attenuation, Represents the pixel point in the high-energy sub-image The initial high-energy X-ray intensity at Represents the pixel point in the high-energy sub-image The intensity of high-energy X-rays after attenuation.

[0010] According to a method for measuring the volume of liquid contraband based on X-ray images provided by the present invention, the volume of the liquid to be detected is determined based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction, and the actual vertical distance represented by each pixel point in the vertical direction, including: For each pixel point, based on the actual height distance corresponding to the pixel point, the actual horizontal distance represented by the pixel point in the horizontal direction, and the actual vertical distance represented by the pixel point in the vertical direction, determine the volume of the liquid to be detected corresponding to the pixel point; The sum of the volumes of the liquid to be detected corresponding to all the pixel points is determined as the volume of the liquid to be detected.

[0011] According to a method for measuring the volume of liquid contraband based on X-ray images provided by the present invention, the method further comprises: Acquiring at least one reference X-ray image of the master part; For each of the reference X-ray images, obtaining a first pixel length of the standard component in the reference X-ray image in the horizontal direction; Determine a horizontal distance represented by each pixel point in the reference X-ray image in the horizontal direction based on the first pixel length and a first actual length of the standard component in the horizontal direction; The average value of the horizontal distances represented by the pixel points in all reference X-ray images in the horizontal direction is determined as the actual horizontal distance.

[0012] According to a method for measuring the volume of liquid contraband based on X-ray images provided by the present invention, the method further comprises: For each of the reference X-ray images, obtaining a second pixel length of the standard component in the reference X-ray image in the vertical direction; Determine a vertical distance represented by each pixel point in the reference X-ray image in the vertical direction based on the second pixel length and a second actual length of the standard part in the vertical direction; The average value of the vertical distances represented by the pixel points in all reference X-ray images in the vertical direction is determined as the actual vertical distance.

[0013] According to a method for measuring the volume of liquid contraband based on an X-ray image provided by the present invention, the method for determining the target liquid type of the liquid to be detected based on the X-ray image comprises: determining a characteristic value of the liquid to be detected based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, and the attenuated low-energy X-ray intensity of the target pixel point, wherein the target pixel point is any pixel point corresponding to the liquid to be detected in the X-ray image, and the characteristic value is a value used to characterize a material property; Based on the characteristic value of the liquid to be detected, the target liquid type of the liquid to be detected is determined.

[0014] According to a method for measuring the volume of liquid contraband based on X-ray images provided by the present invention, the target liquid type of the liquid to be detected is determined based on the characteristic value of the liquid to be detected, including: Determining the relative atomic numbers of the components of the liquid to be detected based on the characteristic values ​​of the liquid to be detected; Based on the correspondence between the liquid type and the relative atomic number interval, the liquid type corresponding to the target relative atomic number interval to which the relative atomic number belongs is determined as the target liquid type.

[0015] According to a method for measuring the volume of liquid contraband based on X-ray images provided by the present invention, the characteristic value of the liquid to be detected is determined based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity and the attenuated low-energy X-ray intensity of the target pixel point, including: The characteristic value of the liquid to be detected is determined based on formula (2): (2)

[0016] Wherein, R represents the characteristic value of the liquid to be detected, Represents the pixel point in the low-energy sub-image The initial low-energy X-ray intensity at Represents the pixel point in the low-energy sub-image The intensity of low-energy X-rays after attenuation, Represents the pixel point in the high-energy sub-image The initial high-energy X-ray intensity at Represents the pixel point in the high-energy sub-image The intensity of high-energy X-rays after attenuation.

[0017] The present invention also provides a liquid contraband volume measuring device based on X-ray images, comprising: a determination module, configured to determine a target liquid type of the liquid to be detected based on the X-ray image when it is determined that there is a liquid to be detected in the package to be detected based on the X-ray image including the package to be detected; The determination module is further configured to determine, when the liquid to be detected is determined to be a liquid contraband based on the target liquid type, an actual height distance represented by each pixel point corresponding to the liquid to be detected in the X-ray image in the height direction; The determination module is also used to determine the volume of the liquid to be detected based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction, and the actual vertical distance represented by each pixel point in the vertical direction.

[0018] The present invention also provides an electronic device, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the method for measuring the volume of liquid contraband based on X-ray images as described above is implemented.

[0019] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the method for measuring the volume of liquid contraband based on X-ray images as described in any one of the above is implemented.

[0020] The present invention also provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the computer program implements any of the above-mentioned methods for measuring the volume of liquid contraband based on X-ray images.

[0021] The method for measuring the volume of liquid contraband based on X-ray images provided by the embodiment of the present invention determines the target liquid type of the liquid to be detected based on the X-ray image when it is determined that the package to be detected contains the liquid to be detected based on the X-ray image including the package to be detected. When the liquid to be detected is determined to be a liquid contraband based on the target liquid type, the actual height distance in the height direction represented by each pixel corresponding to the liquid to be detected in the X-ray image is determined, and the volume of the liquid to be detected is determined based on the actual height distance corresponding to each pixel, the actual horizontal distance represented by each pixel in the horizontal direction, and the actual vertical distance represented by each pixel in the vertical direction. On the one hand, when it is determined that the package to be detected contains the liquid to be detected, the target liquid type of the liquid to be detected can be directly determined based on the X-ray image, so that it can be determined whether the liquid to be detected is a liquid contraband based on the target liquid type, which can simplify the liquid detection process and improve the security inspection efficiency. On the other hand, when the liquid to be detected is determined to be a liquid contraband based on the target liquid type, the volume of the liquid contraband corresponding to each pixel is calculated, and the volume of the liquid to be detected is obtained based on the volume corresponding to each pixel. Based on this volume, the harmfulness of liquid contraband can be estimated, reducing potential safety hazards during security checks and improving the safety of security checks. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 A schematic flow chart of a method for measuring the volume of liquid contraband based on X-ray images provided in an embodiment of the present invention.

[0024] Figure 2 A schematic diagram of an X-ray image provided by an embodiment of the present invention.

[0025] Figure 3 The image obtained by segmenting the X-ray image provided by the embodiment of the present invention.

[0026] Figure 4 This is an X-ray image of a liquid area provided by an embodiment of the present invention.

[0027] Figure 5 A high-energy image corresponding to the X-ray image provided in an embodiment of the present invention.

[0028] Figure 6 A low-energy image corresponding to the X-ray image provided in an embodiment of the present invention.

[0029] Figure 7 A reference X-ray image of a standard component provided in an embodiment of the present invention.

[0030] Figure 8 A schematic diagram of the structure of a liquid contraband volume measurement device based on X-ray images provided in an embodiment of the present invention.

[0031] Fig. 9 A schematic diagram of the physical structure of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] At present, when testing a container filled with liquid, the container filled with liquid is usually placed on a dedicated liquid detector to determine whether the container contains liquid contraband. Therefore, the existing liquid detection process is cumbersome, which directly affects the efficiency of security inspection. Moreover, the existing liquid detection instrument cannot effectively measure the specific volume of the liquid stored in the container, resulting in the inability to estimate the harmfulness of liquid contraband, resulting in low security of security inspection.

[0034] In view of the above problems, an embodiment of the present invention provides a method for measuring the volume of liquid contraband based on X-ray images. In this method, when it is determined that there is a liquid to be detected in the package to be detected, the target liquid type of the liquid to be detected can be directly determined based on the X-ray image, so that it can be determined whether the liquid to be detected is a liquid contraband based on the target liquid type, which can simplify the liquid detection process and improve the security inspection efficiency. When the liquid to be detected is determined to be a liquid contraband based on the target liquid type, the thickness of the liquid contraband at each plane pixel point can be calculated and obtained, and the volume of each plane pixel point can be determined based on the thickness, and then the volume of all plane pixel points under the X-ray image is accumulated, and finally the volume of the liquid contraband contained in the container is calculated. Based on the volume, the harmfulness of the liquid contraband can be estimated, which reduces the potential safety hazards in the security inspection process and improves the safety of the security inspection.

[0035] Combine the following Figures 1 to 7The liquid contraband volume measurement method based on X-ray images provided in an embodiment of the present invention is described. The execution subject of the method can be an electronic device such as a security inspection machine, a computer or a server, or a specially designed intelligent device, or a liquid contraband volume measurement device based on X-ray images set in the electronic device or intelligent device. The liquid contraband volume measurement device based on X-ray images can be implemented by software, hardware or a combination of the two. The method can be applied to various scenarios where security inspections are required, such as bus stations, railway stations, subway stations or high-speed railway stations.

[0036] Figure 1 A flow chart of a method for measuring the volume of liquid contraband based on X-ray images provided in an embodiment of the present invention is shown in FIG. Figure 1 As shown, the method includes: Step 101: when it is determined based on an X-ray image of the package to be inspected that there is a liquid to be inspected in the package to be inspected, determine a target liquid type of the liquid to be inspected based on the X-ray image.

[0037] In this step, since the luggage carried by the passenger is likely to contain a container for containing liquids, during security inspection, it is necessary to determine whether the container in the package to be inspected contains liquids.

[0038] Specifically, Figure 2 A schematic diagram of an X-ray image provided by an embodiment of the present invention, such as Figure 2 As shown, during the security inspection process, an X-ray security inspection machine with dual X-ray sources can be used to perform security inspection scans on the luggage parcels one by one to obtain X-ray images. It should be noted that this X-ray image needs to be a main-view X-ray image obtained along the gravity direction of the luggage parcel as the scanning direction (Z direction).

[0039] When there is an object with a clear container-shaped outline in the X-ray image of the package to be inspected, it can be further determined whether it contains liquid by the color of its internal area. When the color of the internal area of ​​the container is very light and close to white, it means that the container contains air and no liquid.

[0040] in addition, Figure 3 The image obtained by segmenting the X-ray image provided by the embodiment of the present invention, Figure 4 The liquid region X-ray image provided by the embodiment of the present invention is as follows: Figure 3 and Figure 4As shown, the X-ray image can also be segmented, and the image of the liquid area can be extracted from the segmented image as the identification sub-image of the liquid to be detected. It should be noted that the area of ​​the container wall can be removed during the image segmentation process, and only the area where the liquid to be detected exists can be retained, thereby avoiding the influence of the subsequent recognition accuracy of the liquid in the container using the identification sub-image of the liquid to be detected due to the container wall being too thick.

[0041] When it is determined that there is a liquid to be detected in the package to be detected, the target liquid type of the liquid to be detected can be determined based on the X-ray image, where the liquid type includes water, alcohol, gasoline, thinner, acetone, sulfuric acid or diesel, etc.

[0042] Step 102: When it is determined that the liquid to be detected is a liquid contraband based on the target liquid type, determine the actual height distance in the height direction represented by each pixel point corresponding to the liquid to be detected in the X-ray image.

[0043] In this step, liquid contraband may include, for example, alcohol, gasoline, thinner, acetone, sulfuric acid or diesel, and any other liquid that is not allowed to be carried in a vehicle or in a crowd. The actual height distance represented by each pixel in the height direction can be understood as the actual total thickness in the Z direction at each pixel in the liquid area of ​​the X-ray image in the XY rectangular coordinate plane. Among them, the Z direction can be understood as Figure 3 or Figure 4 The direction perpendicular to the paper surface is the gravity direction of the package to be tested.

[0044] After determining the target liquid type of the liquid to be detected, when the liquid to be detected is determined to be a liquid contraband based on the target liquid type, the actual height distance in the height direction of each pixel point in the liquid area where the liquid to be detected is located in the X-ray image will be determined, that is, the actual total thickness in the Z direction. .

[0045] Step 103: Determine the volume of the liquid to be detected based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction, and the actual vertical distance represented by each pixel point in the vertical direction.

[0046] In this step, the actual horizontal distance represented by each pixel in the horizontal direction can be understood as the actual physical length that can be represented in the horizontal direction after the pixel length of each pixel is mapped to the actual world coordinate system. The actual vertical distance represented by each pixel in the vertical direction can be understood as the actual physical length that can be represented in the vertical direction after the pixel length of each pixel is mapped to the actual world coordinate system.

[0047] Based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction, and the actual vertical distance represented by each pixel point in the vertical direction, the volume of the liquid contraband corresponding to each pixel point can be determined, and thus the volume of the entire liquid to be detected can be determined based on the volume corresponding to each pixel point.

[0048] Through the above method, the volume of the liquid contraband corresponding to each pixel point is calculated, and the volume of the liquid to be detected is obtained by adding the volume corresponding to each pixel point. This can effectively overcome the error caused by the liquid volume calculation when using irregular-shaped containers to hold liquids, making the volume detection result of liquid contraband more accurate, thereby helping to estimate the harm caused by liquid contraband and quickly obtain a reliable solution for handling liquid contraband.

[0049] The method for measuring the volume of liquid contraband based on X-ray images provided by the embodiment of the present invention determines the target liquid type of the liquid to be detected based on the X-ray image when it is determined that the package to be detected contains the liquid to be detected based on the X-ray image including the package to be detected. When the liquid to be detected is determined to be a liquid contraband based on the target liquid type, the actual height distance in the height direction represented by each pixel corresponding to the liquid to be detected in the X-ray image is determined, and the volume of the liquid to be detected is determined based on the actual height distance corresponding to each pixel, the actual horizontal distance represented by each pixel in the horizontal direction, and the actual vertical distance represented by each pixel in the vertical direction. On the one hand, when it is determined that the package to be detected contains the liquid to be detected, the target liquid type of the liquid to be detected can be directly determined based on the X-ray image, so that it can be determined whether the liquid to be detected is a liquid contraband based on the target liquid type, which can simplify the liquid detection process and improve the security inspection efficiency. On the other hand, when the liquid to be detected is determined to be a liquid contraband based on the target liquid type, the volume of the liquid contraband corresponding to each pixel is calculated, and the volume of the liquid to be detected is obtained based on the volume corresponding to each pixel. Based on this volume, the harmfulness of liquid contraband can be estimated, reducing potential safety hazards during security checks and improving the safety of security checks.

[0050] Exemplarily, based on the above embodiment, when determining the actual height distance in the height direction represented by each pixel point corresponding to the liquid to be detected in the X-ray image, it can be performed in the following manner: For each pixel point corresponding to the liquid to be detected in the X-ray image, the initial high-energy X-ray intensity of the pixel point in the high-energy sub-image corresponding to the liquid to be detected and the attenuated high-energy X-ray intensity of the pixel point are obtained, and the initial low-energy X-ray intensity of the pixel point in the low-energy sub-image corresponding to the liquid to be detected and the attenuated low-energy X-ray intensity of the pixel point are obtained. Based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity and the attenuated low-energy X-ray intensity, the actual height distance represented by the pixel point in the height direction is determined.

[0051] Specifically, Figure 5 A high-energy image corresponding to the X-ray image provided in an embodiment of the present invention, Figure 6 The low-energy image corresponding to the X-ray image provided in the embodiment of the present invention is as follows: Figure 5 and Figure 6 As shown, after the X-ray security inspection machine with dual X-ray sources scans the package to be inspected, it will not only output the X-ray image corresponding to the package to be inspected, but also output its corresponding high-energy image and low-energy image, wherein the high-energy image is an image formed after the high-energy X-rays are partially attenuated after penetrating the object and the attenuated X-rays are received, and the low-energy image is an image formed after the low-energy X-rays are partially attenuated after penetrating the object and the attenuated X-rays are received.

[0052] Furthermore, according to Figure 3 The liquid contour area in the X-ray sub-image is picked up in the high-energy image and the low-energy sub-image of the liquid to be detected, which corresponds to the high-energy image and the low-energy image.

[0053] For each pixel point corresponding to the liquid to be detected in the X-ray image, the initial high-energy X-ray intensity of the pixel point in the high-energy sub-image and the attenuated high-energy X-ray intensity of the pixel point can be obtained. The initial high-energy X-ray intensity is the X-ray intensity value (unit: W / m 2 ), the initial high-energy X-ray intensity can be set to 100 keV. The attenuated high-energy X-ray intensity is the output data of the high-energy sub-image corresponding to the liquid to be detected.

[0054] For each pixel point corresponding to the liquid to be detected in the X-ray image, it is also necessary to obtain the initial low-energy X-ray intensity of the pixel point in the low-energy sub-image and the low-energy X-ray intensity of the pixel point after attenuation. The initial low-energy X-ray intensity is the X-ray intensity value (unit: W / m 2 ), the initial low-energy X-ray intensity can be set to 20keV. The attenuated low-energy X-ray intensity is the output data of the low-energy sub-image corresponding to the liquid to be detected.

[0055] Furthermore, the actual height distance in the height direction represented by the pixel point can be determined based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, and the attenuated low-energy X-ray intensity. The above method can quickly determine the actual height distance in the height direction represented by the pixel point, thereby improving the efficiency of determining the actual height distance corresponding to each pixel point.

[0056] Exemplarily, when determining the actual height distance represented by the pixel in the height direction based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity and the attenuated low-energy X-ray intensity, the first medium attenuation coefficient corresponding to the target liquid type at the high energy value of the X-ray and the second medium attenuation coefficient corresponding to the target liquid type at the low energy value of the X-ray can be determined based on the correspondence between the liquid type, the X-ray energy value and the medium attenuation coefficient, and the actual height distance represented by the pixel in the height direction is determined based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, the attenuated low-energy X-ray intensity, the first medium attenuation coefficient and the second medium attenuation coefficient.

[0057] Specifically, the corresponding relationship between the liquid type, X-ray energy value and the dielectric attenuation coefficient can be constructed by extracting the dielectric attenuation coefficient of the required liquid contraband from the physical database NIST. The corresponding relationship can be shown in Table 1, for example: Table 1

[0058] By querying the above Table 1, the first medium attenuation coefficient corresponding to the target liquid type under the high energy value of the X-ray and the second medium attenuation coefficient corresponding to the target liquid type under the low energy value of the X-ray can be obtained. For example, assuming that the target liquid type is sulfuric acid, by querying Table 1, it can be obtained that the first medium attenuation coefficient is 0.0278 and the second medium attenuation coefficient is 0.1205.

[0059] Furthermore, the actual height distance represented by the pixel in the height direction can be determined based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, the attenuated low-energy X-ray intensity, the first medium attenuation coefficient, and the second medium attenuation coefficient. By adding the first medium attenuation coefficient and the second medium attenuation coefficient, the accuracy of the actual height distance corresponding to each pixel can be further improved.

[0060] Exemplarily, when determining the actual height distance represented by the pixel in the height direction based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, the attenuated low-energy X-ray intensity, the first medium attenuation coefficient, and the second medium attenuation coefficient, the actual height distance represented by the pixel in the height direction can be determined based on formula (1): (1)

[0061] in, Represents pixel The actual height distance represented in the height direction, represents the attenuation coefficient of the first medium, represents the attenuation coefficient of the second medium, Represents the pixel in the low-energy sub-image The initial low-energy X-ray intensity at Represents the pixel in the low-energy sub-image The intensity of low-energy X-rays after attenuation, Represents the pixel point in the high-energy sub-image The initial high-energy X-ray intensity at Represents the pixel point in the high-energy sub-image The intensity of high-energy X-rays after attenuation.

[0062] In this embodiment, the actual height distance represented by each pixel point in the height direction can be determined quickly and accurately by using the above formula (1).

[0063] Exemplarily, on the basis of the above-mentioned embodiments, when determining the volume of the liquid to be detected based on the actual height distance corresponding to each pixel, the actual horizontal distance represented by each pixel in the horizontal direction, and the actual vertical distance represented by each pixel in the vertical direction, it can be that for each pixel, based on the actual height distance corresponding to the pixel, the actual horizontal distance represented by the pixel in the horizontal direction, and the actual vertical distance represented by the pixel in the vertical direction, the volume of the liquid to be detected corresponding to the pixel is determined, and the sum of the volumes of the liquid to be detected corresponding to all pixels is determined as the volume of the liquid to be detected.

[0064] Specifically, the pixel point can be determined based on formula (3): The corresponding volume of the liquid to be tested : (3)

[0065] in, Indicates the actual horizontal distance represented by the pixel point in the horizontal direction. Indicates the actual vertical distance represented by the pixel in the vertical direction.

[0066] By traversing Figure 4 All pixel points in the XY rectangular coordinate plane shown in , so that the volume of the liquid to be detected can be determined based on the following formula (4): : (4)

[0067] In this embodiment, the volume of the liquid to be detected corresponding to each pixel is determined, and the sum of the volumes of the liquid to be detected corresponding to all the pixels is determined as the volume of the liquid to be detected. In this method, the determination of the volume of the liquid to be detected is refined into the determination of the volume of the liquid to be detected corresponding to each pixel. Therefore, it can effectively overcome the error caused by the calculation of the liquid volume when using an irregularly shaped container to hold the liquid, so that the final volume detection result of the liquid to be detected is more accurate.

[0068] Exemplarily, based on the above embodiments, the actual horizontal distance represented by the pixel points mentioned in the above embodiments in the horizontal direction can be determined by the following method: Acquire at least one reference X-ray image for the standard part, and for each reference X-ray image, acquire a first pixel length of the standard part in the horizontal direction in the reference X-ray image, and determine a horizontal distance represented by each pixel point in the reference X-ray image in the horizontal direction based on the first pixel length and a first actual length of the standard part in the horizontal direction, thereby determining an average value of the horizontal distance represented by each pixel point in the horizontal direction in all reference X-ray images as the actual horizontal distance.

[0069] Specifically, Figure 7 A reference X-ray image of a standard component provided by an embodiment of the present invention, such as Figure 7 As shown, an object with a preset length, width and height can be selected as a standard part, and an X-ray security inspection machine with a dual X-ray source is used to obtain a reference X-ray image of the standard part along the gravity direction of the standard part as the scanning direction (i.e., the vertical Z direction). It should be noted that the selection of the standard part needs to have a clear boundary under X-rays, that is, the reference X-ray image formed has a clear outline to facilitate identification in the reference X-ray image. Usually, a material with an absorption of X-rays between 20% and 70% is selected. In this embodiment, a cubic object made of polyester ethylene and with actual physical dimensions of (100mm×100mm×100mm) in length, width and height is selected as a standard part.

[0070] Place the standard part in the detection area of ​​the X-ray security inspection machine with dual X-ray sources and ensure that it is placed stably. Use the X-ray security inspection machine to scan the standard part N times. During the N scans, the position of the standard part in the detection area is usually adjusted or the rotation angle in the XY rectangular coordinate plane is adjusted, so that N reference X-ray images of the standard part can be obtained, where N is a positive integer greater than or equal to 1.

[0071] For each reference X-ray image, Figure 7 The reference X-ray image of the main viewing angle shown in is used for calibration in the X and Y directions, where the X direction is the horizontal direction and the Y direction is the vertical direction. The first pixel length of the standard part in the reference X-ray image in the X direction is measured and recorded as .

[0072] Since the first actual length of the standard part in the X direction is known, it is recorded as , so that the horizontal distance represented by each pixel in the reference X-ray image in the horizontal direction can be determined based on formula (5) , wherein the first actual length can also be understood as the actual physical length of the standard part in the horizontal direction (in millimeters).

[0073] (5)

[0074] Furthermore, in order to improve the accuracy of the actual horizontal distance, error optimization can also be performed. By traversing N reference X-ray images of standard parts, the average value of the horizontal distance represented by each pixel point in the horizontal direction in all reference X-ray images is solved based on formula (6): : (6)

[0075] in, Represents the horizontal distance represented by the pixel point in the i-th reference X-ray image in the horizontal direction.

[0076] By calculating the average value in the above manner, the error can be reduced, and the average actual horizontal distance corresponding to each pixel point in the X direction can be obtained.

[0077] In this embodiment, the average value of the horizontal distances represented by the pixels in all the reference X-ray images in the horizontal direction is determined as the actual horizontal distance, thereby reducing errors and improving the accuracy of the determined actual horizontal distance.

[0078] Exemplarily, based on the above embodiments, the actual vertical distance represented by the pixel points mentioned in the above embodiments in the vertical direction can be determined by the following method: For each reference X-ray image, a second pixel length of the standard part in the vertical direction in the reference X-ray image is obtained, and based on the second pixel length and the second actual length of the standard part in the vertical direction, the vertical distance represented by each pixel point in the reference X-ray image in the vertical direction is determined, and the average value of the vertical distance represented by each pixel point in the vertical direction in all reference X-ray images is determined as the actual vertical distance.

[0079] Specifically, for each reference X-ray image, Figure 7 After calibration in the X and Y directions, the second pixel length of the standard part in the reference X-ray image in the Y direction, that is, the second pixel length in the vertical direction, is measured and recorded as .

[0080] Since the second actual length of the standard part in the Y direction is known, it is recorded as , so that the vertical distance represented by each pixel in the reference X-ray image in the vertical direction can be determined based on formula (7) , wherein the second actual length can also be understood as the actual physical length of the standard part in the vertical direction (in millimeters).

[0081] (7)

[0082] Furthermore, in order to improve the accuracy of the actual vertical distance, error optimization can also be performed. By traversing N reference X-ray images of standard parts, the average value of the vertical distance represented by each pixel in the vertical direction in all reference X-ray images is solved based on formula (8): : (8)

[0083] in, Represents the vertical distance represented by the pixel point in the i-th reference X-ray image in the vertical direction.

[0084] By calculating the average value in the above manner, the error can be reduced, and the average actual vertical distance corresponding to each pixel point in the Y direction can be obtained.

[0085] In this embodiment, the actual vertical distance is determined as the average value of the vertical distances represented by each pixel in all reference X-ray images in the vertical direction, thereby reducing errors and improving the accuracy of the determined actual vertical distance.

[0086] Illustratively, based on the above embodiments, when determining the target liquid type of the liquid to be detected based on the X-ray image, the characteristic value of the liquid to be detected can be determined based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity and the attenuated low-energy X-ray intensity of the target pixel point. The target pixel point is any pixel point corresponding to the liquid to be detected in the X-ray image, the characteristic value is a value used to characterize the properties of the material, and based on the characteristic value of the liquid to be detected, the target liquid type of the liquid to be detected is determined.

[0087] Specifically, the data information of the low-energy sub-image and the high-energy sub-image corresponding to the liquid to be detected can be used to calculate the R value of the liquid component of the liquid to be detected. The R value is a characteristic value of the property of the reaction substance, which can be calculated from the collected low-energy sub-image and the high-energy sub-image. For example, it can be determined based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, and the attenuated low-energy X-ray intensity of any target pixel corresponding to the liquid to be detected in the X-ray image. In a possible implementation, the characteristic value of the liquid to be detected can be quickly and accurately determined based on formula (2): (2)

[0088] Where R represents the characteristic value of the liquid to be detected, Represents the pixel in the low-energy sub-image The initial low-energy X-ray intensity at Represents the pixel in the low-energy sub-image The intensity of low-energy X-rays after attenuation, Represents the pixel point in the high-energy sub-image The initial high-energy X-ray intensity at Represents the pixel point in the high-energy sub-image The intensity of high-energy X-rays after attenuation.

[0089] After the characteristic value of the liquid to be detected is determined, since the characteristic value can reflect the material property, the target liquid type of the liquid to be detected can be accurately determined based on the characteristic value.

[0090] Exemplarily, when determining the target liquid type of the liquid to be detected based on the characteristic value of the liquid to be detected, the relative atomic number of the components of the liquid to be detected can be determined based on the characteristic value of the liquid to be detected, and based on the correspondence between the liquid type and the relative atomic number interval, the liquid type corresponding to the target relative atomic number interval to which the relative atomic number belongs is determined as the target liquid type.

[0091] Specifically, the relative atomic number Z of the liquid component of the liquid to be detected can be determined according to formula (9): (9)

[0092] In addition, the correspondence between liquid types and relative atomic number ranges can be established in advance, as shown in Table 2: Table 2

[0093] By querying the above-mentioned correspondence, it is possible to determine which liquid type's corresponding relative atomic number interval the relative atomic number Z of the component of the liquid to be detected falls into, and determine the liquid type corresponding to the target relative atomic number interval to which the relative atomic number belongs as the target liquid type of the liquid to be detected, thereby completing the determination of the material properties of the liquid component to be detected.

[0094] When the target liquid type is water, it is considered safe and the package to be detected can pass the security check. When the target liquid type is liquid contraband, the volume of the liquid to be detected can be determined in the manner described in any of the above embodiments.

[0095] In this embodiment, by determining the relative atomic numbers of the components of the liquid to be detected, the target liquid type of the liquid to be detected can be simply and quickly determined based on the relative atomic numbers, thereby improving the efficiency of determining the target liquid type and thus increasing the speed of security inspection.

[0096] The following is a description of the liquid contraband volume measuring device based on X-ray images provided by the present invention. The liquid contraband volume measuring device based on X-ray images described below and the liquid contraband volume measuring method based on X-ray images described above can be referenced to each other.

[0097] Figure 8 A schematic diagram of a liquid contraband volume measurement device based on an X-ray image provided by an embodiment of the present invention, referring to Figure 8 As shown, the liquid contraband volume measurement device 800 based on X-ray images includes: A first determination module 11 is used to determine a target liquid type of the liquid to be detected based on the X-ray image when it is determined that there is a liquid to be detected in the package to be detected based on the X-ray image including the package to be detected; A second determination module 12 is used to determine the actual height distance in the height direction represented by each pixel point corresponding to the liquid to be detected in the X-ray image when the liquid to be detected is determined to be a liquid contraband based on the target liquid type; The third determination module 13 is used to determine the volume of the liquid to be detected based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction, and the actual vertical distance represented by each pixel point in the vertical direction.

[0098] In an exemplary embodiment, the second determining module 12 is specifically configured to: For each pixel point corresponding to the liquid to be detected in the X-ray image, obtaining an initial high-energy X-ray intensity of the pixel point in a high-energy sub-image corresponding to the liquid to be detected, and an attenuated high-energy X-ray intensity of the pixel point; Acquire the initial low-energy X-ray intensity of the pixel point in the low-energy sub-image corresponding to the liquid to be detected, and the attenuated low-energy X-ray intensity of the pixel point; Based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity and the attenuated low-energy X-ray intensity, an actual height distance in the height direction represented by the pixel point is determined.

[0099] In an exemplary embodiment, the second determining module 12 is specifically configured to: Based on the correspondence between the liquid type, the X-ray energy value and the medium attenuation coefficient, determine a first medium attenuation coefficient corresponding to the target liquid type under a high X-ray energy value, and a second medium attenuation coefficient corresponding to the target liquid type under a low X-ray energy value; Based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, the attenuated low-energy X-ray intensity, the first medium attenuation coefficient and the second medium attenuation coefficient, the actual height distance represented by the pixel point in the height direction is determined.

[0100] In an exemplary embodiment, the second determining module 12 is specifically configured to: The actual height distance represented by the pixel point in the height direction is determined based on formula (1): (1)

[0101] in, Represents pixel The actual height distance represented in the height direction, represents the attenuation coefficient of the first medium, represents the attenuation coefficient of the second medium, Represents the pixel point in the low-energy sub-image The initial low-energy X-ray intensity at Represents the pixel point in the low-energy sub-image The intensity of low-energy X-rays after attenuation, Represents the pixel point in the high-energy sub-image The initial high-energy X-ray intensity at Represents the pixel point in the high-energy sub-image The intensity of high-energy X-rays after attenuation.

[0102] In an exemplary embodiment, the third determining module 13 is specifically configured to: For each pixel point, based on the actual height distance corresponding to the pixel point, the actual horizontal distance represented by the pixel point in the horizontal direction, and the actual vertical distance represented by the pixel point in the vertical direction, determine the volume of the liquid to be detected corresponding to the pixel point; The sum of the volumes of the liquid to be detected corresponding to all the pixel points is determined as the volume of the liquid to be detected.

[0103] In an exemplary embodiment, the apparatus further comprises: An acquisition module, used for acquiring at least one reference X-ray image for the standard part; The acquisition module is further used to acquire, for each of the reference X-ray images, a first pixel length of the standard component in the reference X-ray image in the horizontal direction; A fourth determination module, configured to determine a horizontal distance represented by each pixel point in the reference X-ray image in the horizontal direction based on the first pixel length and a first actual length of the standard component in the horizontal direction; The fifth determination module is used to determine the average value of the horizontal distances represented by the pixel points in all reference X-ray images in the horizontal direction as the actual horizontal distance.

[0104] In an exemplary embodiment, the acquisition module is further used to acquire, for each of the reference X-ray images, a second pixel length of the standard part in the reference X-ray image in the vertical direction; a sixth determination module, configured to determine a vertical distance represented by each pixel point in the reference X-ray image in the vertical direction based on the second pixel length and a second actual length of the standard component in the vertical direction; The seventh determination module is used to determine the average value of the vertical distances represented by the pixel points in all reference X-ray images in the vertical direction as the actual vertical distance.

[0105] In an exemplary embodiment, the third determining module 13 is specifically configured to: determining a characteristic value of the liquid to be detected based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, and the attenuated low-energy X-ray intensity of the target pixel point, wherein the target pixel point is any pixel point corresponding to the liquid to be detected in the X-ray image, and the characteristic value is a value used to characterize a material property; Based on the characteristic value of the liquid to be detected, the target liquid type of the liquid to be detected is determined.

[0106] In an exemplary embodiment, the third determining module 13 is specifically configured to: Determining the relative atomic numbers of the components of the liquid to be detected based on the characteristic values ​​of the liquid to be detected; Based on the correspondence between the liquid type and the relative atomic number interval, the liquid type corresponding to the target relative atomic number interval to which the relative atomic number belongs is determined as the target liquid type.

[0107] In an exemplary embodiment, the third determining module 13 is specifically configured to: The characteristic value of the liquid to be detected is determined based on formula (2): (2)

[0108] Wherein, R represents the characteristic value of the liquid to be detected, Represents the pixel point in the low-energy sub-image The initial low-energy X-ray intensity at Represents the pixel point in the low-energy sub-image The intensity of low-energy X-rays after attenuation, Represents the pixel point in the high-energy sub-image The initial high-energy X-ray intensity at Represents the pixel point in the high-energy sub-image The intensity of high-energy X-rays after attenuation.

[0109] The device of this embodiment can be used to execute the method of any embodiment in the embodiment of the liquid contraband volume measurement method based on X-ray images. Its specific implementation process and technical effects are similar to those in the embodiment of the liquid contraband volume measurement method based on X-ray images. For details, please refer to the detailed introduction in the embodiment of the liquid contraband volume measurement method based on X-ray images, which will not be repeated here.

[0110] Fig. 9 A schematic diagram of the physical structure of an electronic device provided by an embodiment of the present invention is shown in FIG. Fig. 9As shown, the electronic device may include: a processor 910, a communication interface 920, a memory 930 and a communication bus 940, wherein the processor 910, the communication interface 920 and the memory 930 communicate with each other through the communication bus 940. The processor 910 may call the logic instructions in the memory 930 to execute the liquid contraband volume measurement method based on the X-ray image, the method comprising: in the case where it is determined based on the X-ray image including the package to be detected that there is a liquid to be detected in the package to be detected, determining the target liquid type of the liquid to be detected based on the X-ray image; in the case where it is determined based on the target liquid type that the liquid to be detected is a liquid contraband, determining the actual height distance in the height direction represented by each pixel corresponding to the liquid to be detected in the X-ray image; and determining the volume of the liquid to be detected based on the actual height distance corresponding to each pixel, the actual horizontal distance represented by each pixel in the horizontal direction and the actual vertical distance represented by each pixel in the vertical direction.

[0111] In addition, the logic instructions in the above-mentioned memory 930 can be implemented in the form of a software functional unit and can be stored in a computer-readable storage medium when it is sold or used as an independent product. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0112] On the other hand, the present invention also provides a computer program product, which includes a computer program. The computer program can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can execute the liquid contraband volume measurement method based on X-ray images provided by the above-mentioned methods, the method including: in a case where it is determined that there is a liquid to be detected in the package to be detected based on an X-ray image including the package to be detected, determining the target liquid type of the liquid to be detected based on the X-ray image; in a case where it is determined that the liquid to be detected is a liquid contraband based on the target liquid type, determining the actual height distance in the height direction represented by each pixel point corresponding to the liquid to be detected in the X-ray image; and determining the volume of the liquid to be detected based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction, and the actual vertical distance represented by each pixel point in the vertical direction.

[0113] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, is implemented to execute the liquid contraband volume measurement method based on X-ray images provided by the above-mentioned methods, the method comprising: in a case where it is determined based on an X-ray image including the package to be detected that there is a liquid to be detected in the package to be detected, determining a target liquid type of the liquid to be detected based on the X-ray image; in a case where it is determined based on the target liquid type that the liquid to be detected is a liquid contraband, determining an actual height distance in the height direction represented by each pixel point corresponding to the liquid to be detected in the X-ray image; and determining the volume of the liquid to be detected based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction, and the actual vertical distance represented by each pixel point in the vertical direction.

[0114] The device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative labor.

[0115] Through the description of the above implementation methods, those skilled in the art can clearly understand that each implementation method can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware. Based on this understanding, the above technical solution is essentially or the part that contributes to the prior art can be embodied in the form of a software product, and the computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a disk, an optical disk, etc., including a number of instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or some parts of the embodiments.

[0116] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for measuring the volume of liquid contraband based on X-ray images, characterized in that: include: In a case where it is determined based on the X-ray image including the package to be inspected that the package to be inspected contains a liquid to be inspected, determining a target liquid type of the liquid to be inspected based on the X-ray image; In the case where the liquid to be detected is determined to be a liquid contraband based on the target liquid type, determining an actual height distance in the height direction represented by each pixel point corresponding to the liquid to be detected in the X-ray image; The volume of the liquid to be detected is determined based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction, and the actual vertical distance represented by each pixel point in the vertical direction.

2. The method for measuring the volume of liquid contraband based on X-ray images according to claim 1, characterized in that: The determining of the actual height distance in the height direction represented by each pixel point corresponding to the liquid to be detected in the X-ray image includes: For each pixel point corresponding to the liquid to be detected in the X-ray image, obtaining an initial high-energy X-ray intensity of the pixel point in a high-energy sub-image corresponding to the liquid to be detected, and an attenuated high-energy X-ray intensity of the pixel point; Acquire the initial low-energy X-ray intensity of the pixel point in the low-energy sub-image corresponding to the liquid to be detected, and the attenuated low-energy X-ray intensity of the pixel point; Based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity and the attenuated low-energy X-ray intensity, an actual height distance in the height direction represented by the pixel point is determined.

3. The method for measuring the volume of liquid contraband based on X-ray images according to claim 2, characterized in that: The determining, based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, and the attenuated low-energy X-ray intensity, an actual height distance represented by the pixel point in the height direction comprises: Based on the correspondence between the liquid type, the X-ray energy value and the medium attenuation coefficient, determine a first medium attenuation coefficient corresponding to the target liquid type under a high X-ray energy value, and a second medium attenuation coefficient corresponding to the target liquid type under a low X-ray energy value; Based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, the attenuated low-energy X-ray intensity, the first medium attenuation coefficient and the second medium attenuation coefficient, the actual height distance represented by the pixel point in the height direction is determined.

4. The method for measuring the volume of liquid contraband based on X-ray images according to claim 3, characterized in that: The determining, based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, the attenuated low-energy X-ray intensity, the first medium attenuation coefficient, and the second medium attenuation coefficient, an actual height distance represented by the pixel point in the height direction includes: The actual height distance represented by the pixel point in the height direction is determined based on formula (1): （1） in, Represents pixel The actual height distance represented in the height direction, represents the attenuation coefficient of the first medium, represents the attenuation coefficient of the second medium, Represents the pixel point in the low-energy sub-image The initial low-energy X-ray intensity at Represents the pixel point in the low-energy sub-image The intensity of low-energy X-rays after attenuation, Represents the pixel point in the high-energy sub-image The initial high-energy X-ray intensity at Represents the pixel point in the high-energy sub-image The intensity of high-energy X-rays after attenuation.

5. The method for measuring the volume of liquid contraband based on X-ray images according to claim 3, characterized in that: The method of determining the volume of the liquid to be detected based on the actual height distance corresponding to each pixel point, the actual horizontal distance represented by each pixel point in the horizontal direction, and the actual vertical distance represented by each pixel point in the vertical direction comprises: For each pixel point, based on the actual height distance corresponding to the pixel point, the actual horizontal distance represented by the pixel point in the horizontal direction, and the actual vertical distance represented by the pixel point in the vertical direction, determine the volume of the liquid to be detected corresponding to the pixel point; The sum of the volumes of the liquid to be detected corresponding to all the pixel points is determined as the volume of the liquid to be detected.

6. The method for measuring the volume of liquid contraband based on X-ray images according to claim 1, characterized in that: The method further comprises: Acquiring at least one reference X-ray image of the master part; For each of the reference X-ray images, obtaining a first pixel length of the standard component in the reference X-ray image in the horizontal direction; Determine a horizontal distance represented by each pixel point in the reference X-ray image in the horizontal direction based on the first pixel length and a first actual length of the standard component in the horizontal direction; The average value of the horizontal distances represented by the pixel points in all reference X-ray images in the horizontal direction is determined as the actual horizontal distance.

7. The method for measuring the volume of liquid contraband based on X-ray images according to claim 6, characterized in that: The method further comprises: For each of the reference X-ray images, obtaining a second pixel length of the standard component in the reference X-ray image in the vertical direction; Determine a vertical distance represented by each pixel point in the reference X-ray image in the vertical direction based on the second pixel length and a second actual length of the standard part in the vertical direction; The average value of the vertical distances represented by the pixel points in all reference X-ray images in the vertical direction is determined as the actual vertical distance.

8. The method for measuring the volume of liquid contraband based on X-ray images according to any one of claims 2 to 5, characterized in that: The step of determining the target liquid type of the liquid to be detected based on the X-ray image comprises: determining a characteristic value of the liquid to be detected based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity, and the attenuated low-energy X-ray intensity of the target pixel point, wherein the target pixel point is any pixel point corresponding to the liquid to be detected in the X-ray image, and the characteristic value is a value used to characterize a material property; Based on the characteristic value of the liquid to be detected, the target liquid type of the liquid to be detected is determined.

9. The method for measuring the volume of liquid contraband based on X-ray images according to claim 8, characterized in that: The step of determining the target liquid type of the liquid to be detected based on the characteristic value of the liquid to be detected includes: Determining the relative atomic numbers of the components of the liquid to be detected based on the characteristic values ​​of the liquid to be detected; Based on the correspondence between the liquid type and the relative atomic number interval, the liquid type corresponding to the target relative atomic number interval to which the relative atomic number belongs is determined as the target liquid type.

10. The method for measuring the volume of liquid contraband based on X-ray images according to claim 8, characterized in that: The determining of the characteristic value of the liquid to be detected based on the initial high-energy X-ray intensity, the attenuated high-energy X-ray intensity, the initial low-energy X-ray intensity and the attenuated low-energy X-ray intensity of the target pixel point comprises: The characteristic value of the liquid to be detected is determined based on formula (2): （2） Wherein, R represents the characteristic value of the liquid to be detected, Represents the pixel point in the low-energy sub-image The initial low-energy X-ray intensity at Represents the pixel point in the low-energy sub-image The intensity of low-energy X-rays after attenuation, Represents the pixel point in the high-energy sub-image The initial high-energy X-ray intensity at Represents the pixel point in the high-energy sub-image The intensity of high-energy X-rays after attenuation.

Images