A method, device and control host for determining target thickness in X-ray imaging

Abstract

The embodiments of the present invention disclose a method, device and control host for determining the thickness of a target in X-ray imaging. The method comprises: acquiring a first image captured by a visible light image acquisition element arranged on an X-ray generating assembly, in which a light-transmitting plane containing a grid pattern is projected onto an image plane; acquiring a second image captured by the visible light image acquisition element, in which the light-transmitting plane is projected onto a target, wherein the target fits the image plane and is located between the light-transmitting plane and the image plane; and determining the thickness of the target based on the difference between the grid pattern in the first image and the grid pattern in the second image. The embodiments of the present invention can determine the target thickness without a three-dimensional camera or a time-of-flight sensor, which can save costs.

Description

Technical Field

[0001] The present invention relates to the technical field of medical equipment, and in particular to a method, a device and a control host for determining target thickness in X-ray imaging. Background Art

[0002] X-rays are electromagnetic radiation with a wavelength between ultraviolet rays and gamma rays. X-rays are penetrating and have different penetrating powers for materials of different densities. In medicine, X-rays are generally used to project human organs and bones to form medical images.

[0003] An X-ray imaging system generally includes an X-ray generating assembly, a Bucky-Wall-Stand (BWS) assembly, an examination bed (table) assembly, a film box assembly containing a flat-panel detector, and a remotely located control host, etc. The X-ray generating assembly uses the high voltage provided by the high-voltage generator to emit X-rays that penetrate and irradiate the imaging target, and forms medical image information of the imaging target on the flat-panel detector. The flat-panel detector sends the medical image information to the control host. The imaging target can stand near the chest stand assembly or lie on the examination bed assembly to receive X-ray photography of various parts such as the head, chest, abdomen, and joints.

[0004] In X-ray applications, it is often necessary to determine the thickness of the imaging target. For example, after determining the thickness of the imaging target, the value of the source-to-object-distance (SOD) can be calculated by combining the value of the source-image-distance (SID), and so on.

[0005] Currently, a three-dimensional (3D) camera or a time of flight (TOF) sensor is usually used to determine the target thickness. However, 3D cameras and TOF sensors are expensive. Therefore, how to determine the target thickness at a low cost is an unresolved problem in X-ray imaging. Summary of the invention

[0006] The embodiments of the present invention provide a method, a device and a control host for determining target thickness in X-ray imaging.

[0007] The technical solution of the embodiment of the present invention is as follows:

[0008] A method for determining target thickness in X-ray imaging, comprising:

[0009] Acquire a first image captured by a visible light image capturing element disposed on an X-ray generating assembly, wherein the light-transmitting plane containing a grid pattern is projected onto an image plane;

[0010] Acquire a second image captured by the visible light image capturing element, in which the light-transmitting plane is projected onto a target, wherein the target fits the image plane and is located between the light-transmitting plane and the image plane;

[0011] Based on a difference between a grid pattern in the first image and a grid pattern in the second image, a thickness of the object is determined.

[0012] It can be seen that the embodiments of the present invention do not need to use a three-dimensional camera or a TOF sensor, but instead determine the thickness of the target based on the difference between the grid patterns contained in the first image in which the transparent plane is projected onto the image plane and the second image in which the transparent plane is projected onto the target, thereby reducing costs.

[0013] In one embodiment, the X-ray generating assembly includes a beam splitter;

[0014] The light-transmitting plane comprises:

[0015] The light-transmitting window of the beam splitter; or

[0016] A light-transmitting plate is parallel to the light-transmitting window of the light beam splitter.

[0017] Therefore, the light-transmitting plane of the embodiment of the present invention has multiple implementations and has good applicability.

[0018] In one embodiment, determining the thickness of the target based on a difference between a grid pattern in the first image and a grid pattern in the second image comprises:

[0019] Determine the distance D between the projection light source and the image plane SID ;

[0020] Determine the total area of ​​the grid pattern in the second image. NOI The total area of ​​the grid pattern in the first image NAI Ratio of Area NOI / Area NAI ;

[0021] Determine the average thickness D of the target T ,in

[0022] It can be seen that the embodiment of the present invention can conveniently calculate the average thickness of the target based on the ratio between the total area of ​​the grid patterns in the first image and the second image.

[0023] In one embodiment, the determining of the total area Area of ​​the grid pattern in the second image NOI The total area of ​​the grid pattern in the first image NAIRatio of Area NOI / Area NAI include:

[0024] Converting the first image into a first grayscale image, and converting the second image into a second grayscale image;

[0025] Detecting a first edge of a grid pattern from the first grayscale image, and detecting a second edge of the grid pattern from the second grayscale image;

[0026] The ratio of the number of pixels of the second edge to the number of pixels of the first edge is determined as the Area NOI / Area NAI .

[0027] Therefore, the embodiments of the present invention can determine the ratio of the total area of ​​the grid pattern according to the ratio of the number of pixels in the grid pattern, so as to facilitate fast calculation.

[0028] In one embodiment, determining the thickness of the target based on a difference between a grid pattern in the first image and a grid pattern in the second image comprises:

[0029] Determine the distance D between the projection light source and the image plane SID ;

[0030] Determine the area Area of ​​the predetermined area k of the grid pattern in the second image NOI_k The area of ​​the predetermined area k of the grid pattern in the first image is Area NAI_k Ratio of Area NOI_k / Area NAI_k ;

[0031] Determine the thickness D of the target at the predetermined area k T_k ,in

[0032] It can be seen that the embodiment of the present invention conveniently calculates the thickness of the predetermined area based on the ratio of the areas of the predetermined area in the first image and the second image.

[0033] In one embodiment, the area of ​​the predetermined area k of the grid pattern in the second image is determined as Area NOI_k The area of ​​the predetermined area k of the grid pattern in the first image is Area NAI_k Ratio of Area NOI_k / Area NAI_k include:

[0034] Converting the first image into a first grayscale image, and converting the second image into a second grayscale image;

[0035] Detecting a first edge of the predetermined area k from the first grayscale image, and detecting a second edge of the predetermined area k from the second grayscale image;

[0036] The ratio of the number of pixels of the second edge to the number of pixels of the first edge is determined as the Area NOI_k / Area NAI_k .

[0037] Therefore, the embodiments of the present invention can determine the ratio of the areas of the predetermined regions according to the ratio of the numbers of pixels in the predetermined regions, so as to facilitate fast calculation.

[0038] In one embodiment, the grid pattern comprises a plurality of squares formed by the intersection of a plurality of horizontal lines and a plurality of vertical lines;

[0039] The plurality of horizontal lines are arranged at equal intervals in the horizontal direction of the light-transmitting plane, and the plurality of vertical lines are arranged at equal intervals in the height direction of the light-transmitting plane.

[0040] It can be seen that the embodiment of the present invention adopts a square grid pattern to facilitate area calculation.

[0041] A device for determining target thickness in X-ray imaging, comprising:

[0042] A first acquisition module, used to acquire a first image captured by a visible light image acquisition element arranged on the X-ray generating assembly, wherein the light-transmitting plane containing a grid pattern is projected onto an image plane;

[0043] A second acquisition module, used for acquiring a second image acquired by the visible light image acquisition element, in which the light-transmitting plane is projected onto a target, wherein the target fits the image plane and is located between the light-transmitting plane and the image plane;

[0044] A determination module is used to determine the thickness of the target based on the difference between the grid pattern in the first image and the grid pattern in the second image.

[0045] It can be seen that the embodiments of the present invention do not need to use a three-dimensional camera or a TOF sensor, but instead determine the thickness of the target based on the difference between the grid patterns contained in the first image in which the transparent plane is projected onto the image plane and the second image in which the transparent plane is projected onto the target, thereby reducing costs.

[0046] In one embodiment, the X-ray generating assembly includes a beam splitter; the light-transmitting plane includes:

[0047] The light-transmitting window of the beam splitter; or

[0048] A light-transmitting plate is parallel to the light-transmitting window of the light beam splitter.

[0049] Therefore, the light-transmitting plane of the embodiment of the present invention has various implementations and has good applicability.

[0050] In one embodiment, the determining module is used to determine the distance D between the projection light source and the image plane. SID ; Determine the total area of ​​the grid pattern in the second image Area NOI The total area of ​​the grid pattern in the first image NAI Ratio of Area NOI / Area NAI ; Determine the average thickness D of the target T ,in

[0051] It can be seen that the embodiment of the present invention can conveniently calculate the average thickness of the target based on the ratio between the total area of ​​the grid patterns in the first image and the second image.

[0052] In one embodiment, the determination module is used to convert the first image into a first grayscale image, and convert the second image into a second grayscale image; detect the first edge of the grid pattern from the first grayscale image, and detect the second edge of the grid pattern from the second grayscale image; determine the ratio of the number of pixels of the second edge to the number of pixels of the first edge as the Area NOI / Area NAI .

[0053] Therefore, the embodiments of the present invention can determine the ratio of the total area of ​​the grid patterns according to the ratio of the number of pixels, so as to facilitate fast calculation.

[0054] In one embodiment, the determining module is used to determine the distance D between the projection light source and the image plane. SID ; Determine the area Area of ​​the predetermined area k of the grid pattern in the second image NOI_k The area of ​​the predetermined area k of the grid pattern in the first image is Area NAI_k Ratio of Area NOI_k / Area NAI_k ; Determine the thickness D of the target at the predetermined area k T_k ,in

[0055] It can be seen that the embodiment of the present invention conveniently calculates the thickness of the predetermined area based on the ratio of the areas of the predetermined area in the first image and the second image.

[0056] In one embodiment, the determining module is used to convert the first image into a first grayscale image and convert the second image into a second grayscale image;

[0057] Detect the first edge of the predetermined area k from the first grayscale image, and detect the second edge of the predetermined area k from the second grayscale image; determine the ratio of the number of pixels of the second edge to the number of pixels of the first edge as the Area NOI_k / Area NAI_k .

[0058] Therefore, the embodiments of the present invention can determine the ratio of the areas of the predetermined regions according to the ratio of the numbers of pixels in the predetermined regions, so as to facilitate fast calculation.

[0059] In one embodiment, the grid pattern includes a plurality of squares formed by the intersection of a plurality of horizontal lines and a plurality of vertical lines; wherein the plurality of horizontal lines are arranged at equal intervals in the horizontal direction of the light-transmitting plane, and the plurality of vertical lines are arranged at equal intervals in the height direction of the light-transmitting plane.

[0060] It can be seen that the embodiment of the present invention adopts a square grid pattern to facilitate area calculation.

[0061] A control host of an X-ray imaging system, comprising a processor and a memory;

[0062] The memory stores an application program executable by the processor, which is used to enable the processor to execute any of the above methods for determining target thickness in X-ray imaging.

[0063] Therefore, the embodiment of the present invention further proposes a control host of an X-ray imaging system, which can determine the thickness of a target without using a three-dimensional camera or a TOF sensor, thereby reducing costs.

[0064] A computer-readable storage medium stores computer-readable instructions for executing any one of the above methods for determining target thickness in X-ray imaging.

[0065] Therefore, the embodiment of the present invention further proposes a computer-readable storage medium, which can determine the thickness of the target without using a three-dimensional camera or a TOF sensor, thereby reducing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 The present invention is a flowchart of a method for determining target thickness in X-ray imaging according to an embodiment of the present invention.

[0067] Figure 2 FIG. 1 is an exemplary schematic diagram of a first image projected onto an image plane by a light-transmitting plate including a grid pattern according to an embodiment of the present invention.

[0068] Figure 3FIG. 1 is an exemplary schematic diagram of a second image of a light-transmitting plate including a grid pattern being projected onto a target according to an embodiment of the present invention.

[0069] Figure 4 FIG. 1 is an exemplary schematic diagram of determining target thickness in X-ray imaging according to an embodiment of the present invention.

[0070] Figure 5 FIG. 1 is a schematic diagram of performing edge detection on a first image according to an embodiment of the present invention.

[0071] Figure 6 FIG. 4 is a schematic diagram of performing edge detection on a second image according to an embodiment of the present invention.

[0072] Figure 7 The figure is an exemplary flow chart of a method for determining target thickness in X-ray imaging according to an embodiment of the present invention.

[0073] Figure 8 4 is a structural diagram of an apparatus for determining target thickness in X-ray imaging according to an embodiment of the present invention.

[0074] Fig. 9 FIG. 4 is an exemplary structural diagram of a control host of an X-ray imaging system according to an embodiment of the present invention.

[0075] The reference numerals are as follows:

[0076] 100 Method for determining target thickness in X-ray imaging 101～103 step 20 First Image 21 Translucent board 22 Grid Pattern 30 Second Image 31 Translucent board 32 Grid Pattern 40 X-ray generating components 41 light source 42 2D Camera 43 Target surface 44 Image Plane 45 Translucent plane 200 Method for determining target thickness in X-ray imaging 201～206 step 800 Device for determining target thickness in X-ray imaging 801 First acquisition module 802 Second acquisition module 803 Determine the module 900 Control host 901 processor 902 Memory DETAILED DESCRIPTION

[0077] In order to make the technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and implementation methods. It should be understood that the specific implementation methods described herein are only used to illustrate the present invention and are not intended to limit the scope of protection of the present invention.

[0078] For the sake of brevity and intuitiveness in description, the scheme of the present invention is explained below by describing several representative implementations. A large number of details in the implementations are only used to help understand the scheme of the present invention. However, it is obvious that the technical scheme of the present invention may not be limited to these details when implemented. In order to avoid unnecessarily obscuring the scheme of the present invention, some implementations are not described in detail, but only a framework is given. Hereinafter, "including" means "including but not limited to", and "according to..." means "at least according to..., but not limited to only according to...". Due to the language habits of Chinese, when the number of a component is not specifically specified below, it means that the component can be one or more, or can be understood as at least one.

[0079] Considering the shortcomings of the prior art of using a three-dimensional camera or a TOF sensor to determine the target thickness in X-ray imaging, an embodiment of the present invention proposes a technical solution for determining the target thickness at a low cost.

[0080] Figure 1 Flow chart of a method for determining target thickness in X-ray imaging according to an embodiment of the present invention. Preferably, the method 100 is executed by a control host in an X-ray imaging system.

[0081] like Figure 1 As shown, the method 100 includes:

[0082] Step 101: Acquire a first image captured by a visible light image acquisition element arranged on an X-ray generating assembly, in which a light-transmitting plane containing a grid pattern is projected onto an image plane.

[0083] Here, the light-transmitting plane is a plane including a grid pattern and adapted to transmit light. The grid pattern in the light-transmitting plane may include one or more geometric patterns (eg, square, rectangle, circle, etc.).

[0084] Preferably, the grid pattern includes a geometric pattern, so as to facilitate the subsequent rapid determination of the difference between the grid patterns. More preferably, the grid pattern may include a plurality of squares formed by the intersection of a plurality of horizontal lines and a plurality of vertical lines, wherein the plurality of horizontal lines are arranged at equal intervals in the horizontal direction of the light-transmitting plane, and the plurality of vertical lines are arranged at equal intervals in the height direction of the light-transmitting plane.

[0085] In one embodiment, the light-transmitting plane is implemented as a light-transmitting plate, and the light-transmitting plate is arranged parallel to the light-transmitting window of the beam spotter of the X-ray generating assembly. For example, a groove is provided at the position of the lower part of the beam spotter close to the light-transmitting window, and the light-transmitting plate can be implemented as a glass substrate adapted to be inserted into the groove. For another example, the light-transmitting plate implemented as a glass substrate can be fixed to the light-transmitting window by bonding, bolts, snaps, etc. A plurality of intersecting horizontal and vertical lines are arranged on the glass substrate to form a plurality of squares, wherein the plurality of horizontal lines are arranged at equal intervals in the horizontal direction of the glass substrate, and the plurality of vertical lines are arranged at equal intervals in the height direction of the glass substrate. For example, black horizontal lines and black vertical lines can be drawn on the glass substrate in a painting manner to form a plurality of squares, or black horizontal lines and black vertical lines can be bonded on the glass substrate to form a plurality of squares.

[0086] In one embodiment, the light-transmitting plane may be implemented as a light-transmitting window of a light beam splitter. Furthermore, a plurality of intersecting horizontal and vertical lines are drawn on the light-transmitting window to form a plurality of squares. For example, black horizontal and vertical lines may be drawn directly on the light-transmitting window in a painting manner to form a plurality of squares, or black horizontal and vertical lines may be bonded on the light-transmitting window to form a plurality of squares.

[0087] The image plane is the medium onto which the light-transmitting plane is projected. The image plane is usually located at the location of the X-ray imaging target. For example, the image plane can be the surface of the examination bed or the panel surface of the chest radiograph stand. The distance between the projection light source and the image plane is the source-image distance. It can be seen that when the projection light source and the image plane are determined, the value of the source-image distance is fixed.

[0088] In step 101, no X-ray imaging target is arranged at the image plane, so when the light source located in the X-ray generating assembly emits light, the light-transmitting plane is projected onto the image plane, and thus the grid pattern in the light-transmitting plane is also projected onto the image plane.

[0089] The visible light image acquisition element arranged on the X-ray generating assembly collects visible light on the image plane by optical shooting to obtain a first image (preferably a two-dimensional image in RGB format) containing a grid pattern and a light-transmitting plane projected onto the image plane. For example, the visible light image acquisition element can be specifically implemented as a two-dimensional camera (camera) or a single-hole camera, etc. The visible light image acquisition element usually includes a lens, an image sensor, and a digital / analog (A / D) converter. The image sensor can be implemented as a charge-coupled device (CCD) or a complementary metal oxide semiconductor (CMOS), etc. The optical image generated by the lens is projected onto the surface of the image sensor to be converted into an electrical signal, and then converted into an image in digital format through the A / D converter.

[0090] In one embodiment, the visible light image acquisition element can be fixed on the tube housing of the X-ray generating assembly or on the beam splitter housing. For example, a groove for accommodating the visible light image acquisition element is arranged on the tube housing or on the beam splitter housing, and the visible light image acquisition element is fixed to the groove by bolt connection, snap connection, wire rope loop, etc. Preferably, the visible light image acquisition element is arranged on the tube housing of the X-ray generating assembly, and the viewport of the visible light image acquisition element is parallel to the emission direction of the X-ray, that is, the visible light image acquisition element and the X-ray image share the same viewport.

[0091] Figure 2 FIG. 1 is an exemplary schematic diagram of a first image projected onto an image plane by a light-transmitting plate including a grid pattern according to an embodiment of the present invention.

[0092] When the light source in the X-ray generating assembly emits light, the light-transmitting plate containing the grid pattern is projected onto the image plane. Wherein: when the imaging mode of the X-ray imaging system is the chest frame mode, the image plane is the panel surface of the chest frame; when the imaging mode of the X-ray imaging system is the examination bed mode, the image plane is the bed surface of the examination bed.

[0093] The visible light image acquisition element arranged on the X-ray generating assembly acquires the following Figure 2 A first image 20 is shown.

[0094] Depend on Figure 2 It can be seen that the first image 20 includes a light-transmitting plate 21 and a grid pattern 22 drawn in the light-transmitting plate 21. The grid pattern 22 includes 8*8 squares formed by the intersection of 9 horizontal lines arranged at equal intervals in the horizontal direction and 9 vertical lines arranged at equal intervals in the height direction, that is, 64 squares. Optionally, 9 horizontal lines can be directly drawn in the horizontal direction and 9 vertical lines can be drawn in the height direction on the light-transmitting window of the beam splitter, so that 8*8 squares, that is, 64 squares, are formed by the intersection of the 9 horizontal lines and the 9 vertical lines.

[0095] After the visible light image acquisition element acquires the first image 20, the first image 20 can be sent to the control host in the X-ray imaging system via a wired interface or a wireless interface. Preferably, the wired interface includes at least one of the following: a universal serial bus interface, a controller area network interface, a serial port, etc.; the wireless interface includes at least one of the following: an infrared interface, a near field communication interface, a Bluetooth interface, a ZigBee interface, a wireless broadband interface, etc. Preferably, after the control host acquires the first image 20, the first image 20 can be displayed on a display screen.

[0096] The above exemplary descriptions are of typical arrangements of light-transmitting planes, image planes and visible light image acquisition elements and typical transmission methods of images. Those skilled in the art will appreciate that such descriptions are merely exemplary and are not intended to limit the scope of protection of the embodiments of the present invention.

[0097] Step 102: Acquire a second image captured by the visible light image capturing element, in which the light-transmitting plane is projected onto a target, wherein the target fits the image plane and is located between the light-transmitting plane and the image plane.

[0098] Here, the target is an object whose thickness needs to be determined, usually an X-ray imaging target. The target can be a biological body or an inanimate object, and the embodiments of the present invention do not limit the specific characteristics of the target.

[0099] The target fits the image plane and is located between the light-transmitting plane and the image plane. Therefore, when the light source in the X-ray generating assembly emits light, the grid pattern in the light-transmitting plane (such as a light-transmitting plate or a light-transmitting window) is projected onto the target. The visible light image acquisition element arranged on the X-ray generating assembly collects visible light on the target surface by optical shooting to obtain a second image (preferably a two-dimensional image in RGB format) in which the light-transmitting plane containing the grid pattern is projected onto the target.

[0100] Compared with the case where the target is not arranged on the image plane, when the target is arranged on the image plane, the thickness of the target causes the projection plane to be closer to the visible light image acquisition element, so the grid pattern in the second image is different from the grid pattern in the first image. The thicker the target, the closer the projection plane is to the visible light image acquisition element, and the smaller the size of the grid pattern is.

[0101] Figure 3 FIG. 1 is an exemplary schematic diagram of a second image projected onto an image plane by a light-transmitting plate including a grid pattern according to an embodiment of the present invention. The object is aligned with the image plane and is located between the light-transmitting plate and the image plane.

[0102] When the light source in the X-ray generating assembly emits light, the light-transmitting plate containing the grid pattern is projected onto the target (i.e., the surface of the target). Wherein: when the imaging mode of the X-ray imaging system is the chest frame mode, the target fits the panel surface of the chest frame and the target is located between the light-transmitting plane and the panel surface of the chest frame; when the imaging mode of the X-ray imaging system is the examination bed mode, the target fits the bed surface of the examination bed and the target is located between the light-transmitting plane and the bed surface of the examination bed.

[0103] When the light source in the X-ray generating assembly emits light, the visible light image acquisition element arranged on the X-ray generating assembly acquires the image as follows: Figure 3 A second image 30 is shown.

[0104] Depend on Figure 3 It can be seen that the second image 30 includes a light-transmitting plate 31 and a grid pattern 32 drawn in the light-transmitting plate 31. Since the thickness of the target will cause the projection plane to be closer to the visible light image acquisition element, the grid pattern 32 in the second image is different from the grid pattern 22 in the first image 20. Among them: the thicker the target, the closer the projection plane is to the visible light image acquisition element, and the smaller the size of the grid pattern. Moreover, since the projection has a linear feature, the size change of the grid pattern has a linear or quasi-linear relationship with the target thickness. Therefore, the thickness of the target can be determined based on the size ratio relationship between one or more squares in the grid pattern 32 of the second image 30 and the corresponding one or more squares in the grid pattern 22 of the first image 20.

[0105] Step 103: Determine the thickness of the target based on the difference between the grid pattern in the first image and the grid pattern in the second image.

[0106] Here, first, the principle of determining the thickness of the target based on the difference between the grid pattern in the first image and the grid pattern in the second image is described.

[0107] Figure 4 FIG. 1 is an exemplary schematic diagram of determining target thickness in X-ray imaging according to an embodiment of the present invention.

[0108] exist Figure 4 In the embodiment, the light source 41 is located in the X-ray generating assembly 40. The position of the light source 41 is usually equal to or close to the position of the X-ray source. For example, a reflector can be arranged at an appropriate position of the beam splitter to reflect the light provided by other light sources to the X-ray source, which is equivalent to arranging the light source 41 at the X-ray source.

[0109] First, no target is arranged on the image plane 44 , and the light emitted by the light source 41 projects the light-transmitting plane 45 containing the grid pattern onto the image plane 44 , and the two-dimensional camera 42 arranged on the X-ray generating assembly 40 captures the first image of the light-transmitting plane 45 projected onto the image plane 44 .

[0110] Then, the target is arranged on the image plane 44, and the light emitted by the light source 41 projects the light-transmitting plane 45 containing the grid pattern onto the target surface 43, and the two-dimensional camera 42 arranged on the X-ray generating assembly 40 collects the second image of the light-transmitting plane projected onto the target surface 43. The distance between the light source 41 and the image plane 44 is the source-image distance parameter D SID ; The thickness of the target is D T Among them, D SID is a known value in the projection process. Therefore, based on D SID The target thickness is determined based on the size ratio of the grid patterns in the first image and the second image.

[0111] In one embodiment, determining the thickness of the target based on the difference between the grid pattern in the first image and the grid pattern in the second image in step 103 includes: determining the distance D between the projection light source and the image plane. SID ; Determine the total area of ​​the grid pattern in the second image Area NOI The total area of ​​the grid pattern in the first image NAI Ratio of Area NOI / Area NAI ; Determine the average thickness D of the target T ,in

[0112] Therefore, the average thickness of the object can be conveniently calculated based on the total area of ​​the grid pattern in the first image and the total area of ​​the grid pattern in the second image.

[0113] In the embodiment of the present invention, the ratio of the number of pixels in the first image and the number of pixels in the grid patterns in the first image can be used to simplify the calculation of the area ratio of the first image and the area ratio of the grid patterns in the first image. Preferably, the total area Area of ​​the grid patterns in the second image is determined. NOI The total area of ​​the grid pattern in the first image NAI Ratio of Area NOI / Area NAI The method comprises: converting the first image into a first grayscale image, converting the second image into a second grayscale image; detecting a first edge of a grid pattern from the first grayscale image, and detecting a second edge of the grid pattern from the second grayscale image; determining the ratio of the number of pixels of the second edge to the number of pixels of the first edge as Area. NOI / Area NAI For example, the Canny algorithm in OpenCV can be used to perform edge detection on the first grayscale image and the second grayscale image respectively; then the first number of all pixels surrounding the first edge of the grid pattern in the first grayscale image and the second number of all pixels surrounding the second edge of the grid pattern in the second grayscale image are counted, and the ratio of the second number to the first number is determined as Area NOI / Area NAI .

[0114] In one embodiment, determining the thickness of the target based on the difference between the grid pattern in the first image and the grid pattern in the second image in step 103 includes: determining the distance D between the projection light source and the image plane. SID ; Determine the area Area of ​​the predetermined area k of the grid pattern in the second image NOI_k The area of ​​the predetermined area k of the grid pattern in the first image is Area NAI_k Ratio of Area NOI_k / Area NAI_k ; Determine the thickness D of the target at the predetermined area k T_k ,in For example, the predetermined area k may be any square or a combination of any multiple squares in the grid image.

[0115] Therefore, embodiments of the present invention can also conveniently calculate the thickness of a predetermined area in a target.

[0116] In the embodiment of the present invention, the ratio of the number of pixels in the first image and the respective predetermined areas in the first image may be used to simplify the calculation of the area ratio of the first image and the respective predetermined areas in the first image.

[0117] Preferably, the area Area of ​​the predetermined area k of the grid pattern in the second image is determined NOI_k The area of ​​the predetermined area k of the grid pattern in the first image is Area NAI_k Ratio of Area NOI_k / Area NAI_k The method comprises: converting the first image into a first grayscale image, converting the second image into a second grayscale image; detecting a first edge of a predetermined area k of the grid pattern from the first grayscale image, and detecting a second edge of the predetermined area k of the grid pattern from the second grayscale image; determining the ratio of the number of pixels of the second edge to the number of pixels of the first edge as Area NOI_k / Area NAI_k .

[0118] by Figure 2-Figure 3 For example, assuming that the predetermined area k includes 3 squares from left to right in the first row in the height direction of the light-transmitting plate. The Canny algorithm in OpenCV can be used to perform edge detection on the first grayscale image and the second grayscale image respectively; then the first number of all pixel points within the first edge of the 3 squares from left to right in the first row in the height direction of the light-transmitting plate in the first grayscale image and the second number of all pixel points within the second edge of the grid pattern surrounding the 3 squares from left to right in the first row in the height direction of the light-transmitting plate in the second grayscale image are counted, and then the ratio of the second number to the first number is determined as Area NOI / Area NAI .

[0119] The above description is exemplified by taking the predetermined area including 3 squares as an example. In fact, the predetermined area can be implemented as any number of squares, wherein when the predetermined area only includes 1 square, the most accurate thickness can be calculated for the target.

[0120] Based on the edge detection process, the complete edge of the grid pattern or the edges of any number of squares in the grid pattern can be detected. Figure 5 FIG. 1 is a schematic diagram of performing edge detection on a first image according to an embodiment of the present invention. Figure 6 FIG. 1 is a schematic diagram of performing edge detection on a second image according to an embodiment of the present invention. Figure 5 In the detection Figure 2 The complete edge of the grid pattern 22 shown; Figure 6 In the detection Figure 3 The full edges of the grid pattern 32 are shown.

[0121] When applying the embodiment of the present invention, a first image database containing the source image distance corresponding to the source image distance can be pre-established. Then, in the subsequent application of determining the target thickness, the corresponding first image is retrieved from the first image database based on the source image distance, thereby accelerating the execution speed of the embodiment of the present invention.

[0122] Figure 7 The figure is an exemplary flow chart of a method for determining target thickness in X-ray imaging according to an embodiment of the present invention.

[0123] like Figure 7 As shown, the method includes:

[0124] Step 201: Retrieve a first image corresponding to the source-image distance from a first image database, wherein the first image is an image captured by a visible light image acquisition element on an X-ray generating assembly, wherein a light-transmitting plane containing a predetermined grid pattern is projected onto an image plane, wherein the distance between the projecting light source and the image plane is the source-image distance.

[0125] Step 202: The visible light image acquisition element acquires a second image of the light-transmitting plane projected onto a target, wherein the target is arranged between the light-transmitting plane and the image plane and the target fits the image plane.

[0126] Step 203: converting the first image into a first grayscale image, and converting the second image into a second grayscale image.

[0127] Step 204: performing edge detection on the first grayscale image to determine a first edge of the grid pattern, and performing edge detection on the second grayscale image to determine an edge of the grid pattern.

[0128] Step 205: Count the number of pixels in the first edge, and count the number of pixels in the second edge.

[0129] Step 206: Determine the thickness of the target based on the source-image distance and the ratio of the number of pixels in the first edge to the number of pixels in the second edge.

[0130] Based on the above description, an embodiment of the present invention further proposes a device for determining target thickness in X-ray imaging.

[0131] Figure 8 4 is a structural diagram of an apparatus for determining target thickness in X-ray imaging according to an embodiment of the present invention.

[0132] like Figure 8 As shown, the device 800 includes:

[0133] A first acquisition module 801 is used to acquire a first image captured by a visible light image acquisition element arranged on an X-ray generating assembly, wherein the light-transmitting plane containing a grid pattern is projected onto an image plane;

[0134] A second acquisition module 802 is used to acquire a second image acquired by the visible light image acquisition element, in which the light-transmitting plane is projected onto a target, wherein the target fits the image plane and is located between the light-transmitting plane and the image plane;

[0135] The determination module 803 is configured to determine the thickness of the target based on a difference between the grid pattern in the first image and the grid pattern in the second image.

[0136] In one embodiment, the X-ray generating assembly includes a beam splitter; the light-transmitting plane includes: a light-transmitting window of the beam splitter; or a light-transmitting plate, wherein the light-transmitting plate is parallel to the light-transmitting window of the beam splitter.

[0137] In one embodiment, the determination module 803 is used to determine the distance D between the projection light source and the image plane. SID ; Determine the total area of ​​the grid pattern in the second image Area NOI The total area of ​​the grid pattern in the first image NAI Ratio of Area NOI / Area NAI ; Determine the average thickness D of the target T ,in

[0138] In one embodiment, the determination module 803 is used to convert the first image into a first grayscale image and the second image into a second grayscale image; detect the first edge of the grid pattern from the first grayscale image and the second edge of the grid pattern from the second grayscale image; determine the ratio of the number of pixels of the second edge to the number of pixels of the first edge as the Area NOI / Area NAI .

[0139] In one embodiment, the determination module 803 is used to determine the distance D between the projection light source and the image plane. SID ; Determine the area Area of ​​the predetermined area k of the grid pattern in the second image NOI_k The area of ​​the predetermined area k of the grid pattern in the first image is Area NAI_k Ratio of Area NOI_k / Area NAI_k ; Determine the thickness D of the target at the predetermined area k T_k ,in

[0140] In one embodiment, the determination module 803 is used to convert the first image into a first grayscale image, convert the second image into a second grayscale image; detect the first edge of the predetermined area k of the grid pattern from the first grayscale image, and detect the second edge of the predetermined area k of the grid pattern from the second grayscale image; determine the ratio of the number of pixels of the second edge to the number of pixels of the first edge as the Area NOI_k / Area NAI_k .

[0141] In one embodiment, the grid pattern includes a plurality of squares formed by the intersection of a plurality of horizontal lines and a plurality of vertical lines; wherein the plurality of horizontal lines are arranged at equal intervals in the horizontal direction of the light-transmitting plane, and the plurality of vertical lines are arranged at equal intervals in the height direction of the light-transmitting plane.

[0142] Based on the above description, an embodiment of the present invention further proposes a control host of an X-ray imaging system.

[0143] Fig. 9 FIG. 4 is an exemplary structural diagram of a control host of an X-ray imaging system according to an embodiment of the present invention.

[0144] like Fig. 9 As shown, the control host 900 includes a processor 901, a memory 902, and a computer program stored in the memory 902 and executable on the processor 901. When the computer program is executed by the processor 901, the method 100 for determining the target thickness in X-ray imaging as described above is implemented. Among them, the memory 902 can be specifically implemented as a variety of storage media such as an electrically erasable programmable read-only memory (EEPROM), a flash memory (Flash memory), and a programmable program read-only memory (PROM). The processor 901 can be implemented as including one or more central processing units or one or more field programmable gate arrays, wherein the field programmable gate array integrates one or more central processing unit cores. Specifically, the central processing unit or the central processing unit core can be implemented as a CPU, an MCU, a DSP, and the like.

[0145] It should be noted that not all steps and modules in the above processes and structure diagrams are necessary, and some steps or modules can be ignored according to actual needs. The execution order of each step is not fixed and can be adjusted as needed. The division of each module is only for the convenience of describing the functional division adopted. In actual implementation, a module can be implemented by multiple modules, and the functions of multiple modules can also be implemented by the same module. These modules can be located in the same device or in different devices.

[0146] The hardware modules in each embodiment can be implemented mechanically or electronically. For example, a hardware module may include a specially designed permanent circuit or logic device (such as a dedicated processor, such as an FPGA or ASIC) for performing a specific operation. The hardware module may also include a programmable logic device or circuit (such as a general-purpose processor or other programmable processor) temporarily configured by software to perform a specific operation. As for whether to implement the hardware module mechanically, or using a dedicated permanent circuit, or using a temporarily configured circuit (such as configured by software), it can be decided based on cost and time considerations.

[0147] The present invention also provides a machine-readable storage medium, storing instructions for a machine to perform a method as described in the present application. Specifically, a system or device equipped with a storage medium can be provided, on which a software program code for realizing the functions of any of the embodiments described in the above embodiments is stored, and the computer (or CPU or MPU) of the system or device reads out and executes the program code stored in the storage medium. In addition, the operating system etc. operated on the computer can also be made to complete part or all of the actual operations by instructions based on the program code. The program code read out from the storage medium can also be written to a memory provided in an expansion board inserted into the computer or to a memory provided in an expansion unit connected to the computer, and then the CPU etc. installed on the expansion board or expansion unit can be made to perform part and all of the actual operations based on the instructions of the program code, thereby realizing the functions of any of the embodiments described in the above embodiments.

[0148] Storage media implementations for providing program code include floppy disks, hard disks, magneto-optical disks, optical disks (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), magnetic tapes, non-volatile memory cards, and ROMs. Optionally, program code can be downloaded from a server computer or cloud via a communication network.

[0149] In this article, "schematic" means "serving as an example, instance or explanation", and any diagram or implementation method described as "schematic" in this article should not be interpreted as a more preferred or more advantageous technical solution. In order to make the drawings concise, only the parts related to the present invention are schematically shown in each figure, and do not represent the actual structure of the product. In addition, in order to make the drawings concise and easy to understand, in some figures, only one of the parts with the same structure or function is schematically drawn, or only one of them is marked. In this article, "one" does not mean that the number of the relevant parts of the present invention is limited to "only one", and "one" does not mean that the number of the relevant parts of the present invention is "more than one". In this article, "upper", "lower", "front", "back", "left", "right", "inside", "outside", etc. are only used to indicate the relative position relationship between the relevant parts, rather than to limit the absolute position of these relevant parts.

[0150] The above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method (100) for determining target thickness in X-ray imaging, characterized in that: include: Acquire a first image (101) of a light-transmitting plane containing a grid pattern projected onto an image plane, which is acquired by a visible light image acquisition element arranged on an X-ray generating assembly; Acquire a second image captured by the visible light image capturing element, in which the light-transmitting plane is projected onto a target, wherein the target fits the image plane and is located between the light-transmitting plane and the image plane (102); Determining the thickness of the target based on a size ratio of a grid pattern in the first image to a grid pattern in the second image and a distance between a projection light source and the image plane (103); Wherein, the projection light source is located in the X-ray generating assembly.

2. The method (100) for determining target thickness in X-ray imaging according to claim 1, characterized in that: The X-ray generating assembly also includes a beam collector; The light-transmitting plane comprises: The light-transmitting window of the beam splitter; or A light-transmitting plate is parallel to the light-transmitting window of the light beam splitter.

3. The method (100) for determining target thickness in X-ray imaging according to claim 1, characterized in that: The determining the thickness of the target based on the size ratio of the grid pattern in the first image to the grid pattern in the second image and the distance between the projection light source and the image plane (103) comprises: Determine the distance D between the projection light source and the image plane SID ; Determine the total area of ​​the grid pattern in the second image. NOI The total area of ​​the grid pattern in the first image NAI Ratio of Area NOI / Area NAI ; Determine the average thickness D of the target T ,in 4. The method (100) for determining target thickness in X-ray imaging according to claim 3, characterized in that: Determining the total area of ​​the grid pattern in the second image NOI The total area of ​​the grid pattern in the first image NAI Ratio of Area NOI / Area NAI include: Converting the first image into a first grayscale image, and converting the second image into a second grayscale image; Detecting a first edge of a grid pattern from the first grayscale image, and detecting a second edge of the grid pattern from the second grayscale image; The ratio of the number of pixels of the second edge to the number of pixels of the first edge is determined as the Area NOI / Area NAI .

5. The method (100) for determining target thickness in X-ray imaging according to claim 1, characterized in that: The determining the thickness of the target based on the size ratio of the grid pattern in the first image to the grid pattern in the second image and the distance between the projection light source and the image plane (103) comprises: Determine the distance D between the projection light source and the image plane SID ; Determine the area Area of ​​the predetermined area k of the grid pattern in the second image NOI_k The area of ​​the predetermined area k of the grid pattern in the first image is Area NAI_k Ratio of Area NOI_k / Area NAI_k ; Determine the thickness D of the target at the predetermined area k T_k ,in 6. The method (100) for determining target thickness in X-ray imaging according to claim 5, characterized in that: The area of ​​the predetermined area k of the grid pattern in the second image is determined as Area NOI_k The area of ​​the predetermined area k of the grid pattern in the first image is Area NAI_k Ratio of Area NOI_k / Area NAI_k include: Converting the first image into a first grayscale image, and converting the second image into a second grayscale image; Detecting a first edge of the predetermined area k from the first grayscale image, and detecting a second edge of the predetermined area k from the second grayscale image; The ratio of the number of pixels of the second edge to the number of pixels of the first edge is determined as the Area NOI_k / Area NAI_k .

7. The method (100) for determining target thickness in X-ray imaging according to any one of claims 1 to 6, characterized in that: The grid pattern includes a plurality of squares formed by the intersection of a plurality of horizontal lines and a plurality of vertical lines; The plurality of horizontal lines are arranged at equal intervals in the horizontal direction of the light-transmitting plane, and the plurality of vertical lines are arranged at equal intervals in the height direction of the light-transmitting plane.

8. A device (800) for determining target thickness in X-ray imaging, characterized in that: include: A first acquisition module (801) is used to acquire a first image captured by a visible light image acquisition element arranged on an X-ray generating assembly, wherein the first image is projected onto an image plane from a light-transmitting plane containing a grid pattern; A second acquisition module (802) is used to acquire a second image acquired by the visible light image acquisition element, in which the light-transmitting plane is projected onto a target, wherein the target fits the image plane and is located between the light-transmitting plane and the image plane; A determination module (803) for determining the thickness of the target based on a size ratio of a grid pattern in the first image to a grid pattern in the second image and a distance between a projection light source and the image plane; Wherein, the projection light source is located in the X-ray generating assembly.

9. The device (800) for determining target thickness in X-ray imaging according to claim 8, characterized in that: The X-ray generating assembly further includes a beam splitter; the light-transmitting plane includes: The light-transmitting window of the beam splitter; or A light-transmitting plate is parallel to the light-transmitting window of the light beam splitter.

10. The device (800) for determining target thickness in X-ray imaging according to claim 8, characterized in that: The determining module (803) is used to determine the distance D between the projection light source and the image plane. SID ; Determine the total area of ​​the grid pattern in the second image Area NOI The total area of ​​the grid pattern in the first image NAI Ratio of Area NOI / Area NAI ; Determine the average thickness D of the target T ,in 11. The device (800) for determining target thickness in X-ray imaging according to claim 10, characterized in that: The determination module (803) is used to convert the first image into a first grayscale image, and convert the second image into a second grayscale image; detect a first edge of the grid pattern from the first grayscale image, and detect a second edge of the grid pattern from the second grayscale image; determine the ratio of the number of pixels of the second edge to the number of pixels of the first edge as the Area NOI / Area NAI .

12. The device (800) for determining target thickness in X-ray imaging according to claim 8, characterized in that: The determining module (803) is used to determine the distance D between the projection light source and the image plane. SID ; Determine the area Area of ​​the predetermined area k of the grid pattern in the second image NOI_k The area of ​​the predetermined area k of the grid pattern in the first image is Area NAI_k Ratio of Area NOI_k / Area NAI_k ; Determine the thickness D of the target at the predetermined area k T_k ,in 13. The device (800) for determining target thickness in X-ray imaging according to claim 12, characterized in that: The determining module (803) is used to convert the first image into a first grayscale image, and convert the second image into a second grayscale image; Detect the first edge of the predetermined area k from the first grayscale image, and detect the second edge of the predetermined area k from the second grayscale image; determine the ratio of the number of pixels of the second edge to the number of pixels of the first edge as the Area NOI_k / Area NAI_k .

14. The device (800) for determining target thickness in X-ray imaging according to any one of claims 8 to 13, characterized in that: The grid pattern includes a plurality of squares formed by the intersection of a plurality of horizontal lines and a plurality of vertical lines; wherein the plurality of horizontal lines are arranged at equal intervals in the horizontal direction of the light-transmitting plane, and the plurality of vertical lines are arranged at equal intervals in the height direction of the light-transmitting plane.

15. A control host (900) of an X-ray imaging system, characterized in that: comprising a processor (901) and a memory (902); The memory (902) stores an application program that can be executed by the processor (901), which is used to enable the processor (901) to execute the method (100) for determining target thickness in X-ray imaging according to any one of claims 1 to 7.

16. A computer-readable storage medium, characterized in that: Computer readable instructions are stored therein, and the computer readable instructions are used to execute the method (100) for determining target thickness in X-ray imaging according to any one of claims 1 to 7.

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