Method and System for Determining Central Channel Position of Scanning Data of Multi-Metal Needle Device

Abstract

The present disclosure provides a method and system for determining the central channel position of multi-metal needle device scanning data, which relates to the technical field of CT systems. The method includes: designing a phantom device as a multi-metal needle device, where the multi-metal needle device includes a plurality of straight metal needles that are parallel to each other in space; scanning the multi-metal needle device to obtain corresponding scanning data, and the scanning data includes a plurality of discrete trajectory curves corresponding to the plurality of metal needles; identifying all intersection point groups of all the discrete trajectory curves, any two discrete trajectory curves have two intersection point groups, and each intersection point group is a discretized point group of the common area where two discrete trajectory curves intersect; determining the channel coordinate positions corresponding to each intersection point group, and determining the mean value of the channel coordinate positions corresponding to each intersection point group to obtain the central channel position. The present disclosure can obtain an accurate central channel position without relying on the accuracy of the rotation angle position.

Description

Technical Field

[0001] The present disclosure relates to the technical field of CT systems, and in particular, to a method and system for determining the position of the central channel of scanning data of a multi-metal needle device. Background Art

[0002] In the rotational geometry of a CT system, the central channel is a key parameter. The central channel refers to the position of the channel projection of the light source focal spot on the detector rotation plane after passing through the rotation center. After the CT system is designed, the central channel is often a fixed value. However, due to errors in the mechanical precision of various components (such as machining, mechanical assembly, etc.), the position of the central channel deviates from the preset target position, and the position calculation of the central channel is inaccurate.

[0003] Regarding the problem that the position calculation of the central channel is inaccurate due to errors in mechanical precision in the related art, no effective technical solution has been proposed yet. Summary of the Invention

[0004] The main objective of the present disclosure is to provide a method and system for determining the position of the central channel of scanning data of a multi-metal needle device, so as to solve the problem that the position calculation of the central channel is inaccurate due to errors in mechanical precision in the related art.

[0005] To achieve the above objective, the first aspect of the present disclosure provides a method for determining the position of the central channel of scanning data of a multi-metal needle device, including:

[0006] Designing a phantom device as a multi-metal needle device, where the multi-metal needle device includes a plurality of straight metal needles that are parallel to each other in space, and the multi-metal needle device is used to correct the mechanical position of the CT system tube or correct the position of the light source focal spot;

[0007] Scanning the multi-metal needle device to obtain corresponding scanning data. When scanning, all the metal needles on the multi-metal needle device are perpendicular to the rotation acquisition plane of the CT system. The scanning data includes a plurality of discrete trajectory curves corresponding to the metal needles;

[0008] Identifying all the intersection groups of all the discrete trajectory curves. Any two discrete trajectory curves have two intersection groups, and each intersection group is a discretized point group in the common area where the two discrete trajectory curves intersect; and

[0009] Determining the channel coordinate positions corresponding to each intersection group, and determining the mean value of the channel coordinate positions corresponding to each intersection group to obtain the central channel position.

[0010] Optionally, the number of metal needles in the multi-metal needle device is N, and N is an integer greater than or equal to 2;

[0011] When N is greater than 2, any straight line in the rotation acquisition plane cannot pass through three metal needles simultaneously, and the three metal needles are not in the same plane.

[0012] Optionally, scan the multi-metal needle device to obtain corresponding scan data, including:

[0013] Scan the air when the multi-metal needle device is not placed to obtain air data P air (c, s, v);

[0014] Rotate and acquire the multi-metal needle device to obtain projection data P(c, s, v);

[0015] Use the air data to perform air correction on the projection data according to the following formula to obtain corrected data A(c, s, v):

[0016]

[0017] Calculate the mean value in the data layer direction of the corrected data according to the following formula to obtain a sinogram A(c, v); [[ID=2l]]

[0018]

[0019] where c, s, and v are the channel index, layer index, and projection angle index respectively, and end is the total number of layer indices.

[0020] Optionally, identify all intersection point groups of all discretized trajectory curves, including:

[0021] Determine the number T of intersection point groups of all discretized trajectory curves according to the following formula:

[0022] T = N * (N - 1)

[0023] where N is the number of metal needles in the multi-metal needle device.

[0024] Optionally, determine the channel coordinate positions corresponding to each intersection point group, including:

[0025] Calculate the channel coordinate position Pos(t) of each intersection point group according to the following formula:

[0026]

[0027] where I(t) is the total number of pixel points corresponding to the t-th intersection point group in the sinogram, c(t, i) and v(t, i) are the channel index and projection angle index corresponding to the i-th pixel point of the t-th intersection point group respectively, A(c(t, i), v(t, i)) is the sinogram, t ∈ [1, T], and T is the number of intersection point groups of all discretized trajectory curves.

[0028] Further, determine the mean of the channel coordinate positions corresponding to each intersection point group to obtain the central channel position, including:

[0029] Calculate the mean of the channel coordinate positions corresponding to T intersection point groups according to the following formula to obtain the central channel position:

[0030]

[0031] where CenterChannelPos is the central channel position in the current state of the CT system.

[0032] The second aspect of the present disclosure provides a central channel position determination system for scanning data of a multi-metal needle device, including:

[0033] A design unit for designing a phantom device as a multi-metal needle device, where the multi-metal needle device includes a plurality of straight metal needles that are parallel to each other in space, and the multi-metal needle device is used to correct the mechanical position of the CT system tube or correct the focal spot position of the light source;

[0034] A scanning unit for scanning the multi-metal needle device to obtain corresponding scanning data. When scanning, all metal needles on the multi-metal needle device are perpendicular to the rotation acquisition plane of the CT system, where the scanning data includes a plurality of discrete trajectory curves corresponding to the metal needles;

[0035] An identification unit for identifying all intersection point groups of all discrete trajectory curves, where any two discrete trajectory curves have two intersection point groups, and each intersection point group is a discretized point group in the common area where the two discrete trajectory curves intersect; and

[0036] A determination unit for determining the channel coordinate positions corresponding to each intersection point group and determining the mean of the channel coordinate positions corresponding to each intersection point group to obtain the central channel position.

[0037] Optionally, the number of metal needles in the multi-metal needle device is N, and N is an integer greater than or equal to 2;

[0038] When N is greater than 2, any straight line in the rotation acquisition plane cannot pass through three metal needles at the same time, and the three metal needles are not in the same plane.

[0039] The third aspect of the present disclosure provides a computer-readable storage medium, and the computer-readable storage medium stores computer instructions for causing a computer to execute the multi-metal needle device scanning data central channel position determination method provided in any item of the first aspect.

[0040] A fourth aspect of the present disclosure provides an electronic device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor to enable the at least one processor to execute the method for determining the central channel position of the multi-metal needle device scanning data provided in any one of the first aspects.

[0041] In the method for determining the central channel position of the multi-metal needle device scanning data provided by the present disclosure, the phantom device is designed as a multi-metal needle device, wherein the multi-metal needle device includes a plurality of straight metal needles that are parallel to each other in space, and the multi-metal needle device is used to correct the mechanical position of the CT system tube or correct the focal spot position of the light source; correcting the mechanical position of the CT system tube or correcting the focal spot position of the light source can adjust the central channel to a preset target position;

[0042] Scan the multi-metal needle device to obtain corresponding scan data. When scanning, all the metal needles on the multi-metal needle device are perpendicular to the rotation acquisition plane of the CT system. Among them, the scan data includes a plurality of discrete trajectory curves corresponding to the metal needles; identify all the intersection groups of all the discrete trajectory curves. Among them, any two discrete trajectory curves have two intersection groups, and each intersection group is a discretized point group of the common area where the two discrete trajectory curves intersect;

[0043] Determine the channel coordinate positions corresponding to each intersection group, and determine the average value of the channel coordinate positions corresponding to each intersection group to obtain the central channel position. Through the average value of the channel coordinate positions corresponding to each intersection group, an accurate central channel position can be obtained without relying on the accuracy of the rotation angle position, and the mechanical position of the CT system tube or the focal spot position of the light source can be accurately determined, solving the problem in the related art that the mechanical accuracy has errors, resulting in inaccurate calculation of the position of the central channel. Description of the Drawings

[0044] In order to more clearly illustrate the specific embodiments of the present disclosure or the technical solutions in the related art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the related art. Obviously, the drawings in the following description are only some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0045] Figure 1 Schematic flow chart of the method for determining the central channel position of the multi-metal needle device scanning data provided by the embodiment of the present disclosure;

[0046] Figure 2 Schematic diagram of the multi-metal needle device provided by the embodiment of the present disclosure;

[0047] Figure 3 Scanning data corresponding to the multi-metal needle devices with four different numbers of metal needles provided in the embodiments of the present disclosure;

[0048] Figure 4 Sinogram obtained by scanning the multi-metal needle device provided in the embodiments of the present disclosure;

[0049] Figure 5 Relationship diagram of the detector projection positions corresponding to the coincidence points of the projections of any two metal needles in the scanning plane provided in the embodiments of the present disclosure;

[0050] Figure 6 Schematic diagram of the intersection group provided in the embodiments of the present disclosure;

[0051] Figure 7 Flow effect diagram of the method for determining the central channel position of the scanning data of the multi-metal needle device provided in the embodiments of the present disclosure;

[0052] Figure 8 Block diagram of the system for determining the central channel position of the scanning data of the multi-metal needle device provided in the embodiments of the present disclosure;

[0053] Figure 9 Block diagram of the electronic device provided in the embodiments of the present disclosure. Detailed implementation manners

[0054] In order to enable those skilled in the art to better understand the solutions of the present disclosure, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present disclosure.

[0055] It should be noted that the terms "first", "second", etc. in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances for the embodiments of the present disclosure described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily need to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0056] In the present disclosure, the orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "middle", "vertical", "horizontal", "lateral", "longitudinal", etc. is based on the orientation or positional relationship shown in the drawings. These terms are mainly used to better describe the present disclosure and its embodiments, and are not used to limit that the indicated devices, elements or components must have a specific orientation, or be constructed and operated in a specific orientation.

[0057] Moreover, in addition to being used to represent the orientation or positional relationship, some of the above terms may also be used to represent other meanings. For example, the term "upper" may also be used to represent a certain attachment relationship or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in the present disclosure can be understood according to specific circumstances.

[0058] In addition, the terms "mounted", "arranged", "provided with", "connected", "linked", "socketed" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral structure; it may be a mechanical connection or an electrical connection; it may be directly connected, or indirectly connected through an intermediate medium, or there may be internal communication between two devices, elements or components. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0059] It should be noted that, without conflict, the embodiments in the present disclosure and the features in the embodiments may be combined with each other. The present disclosure will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0060] In the rotational geometry of a CT system, the central channel is a key parameter. The central channel refers to the channel projection position on the detector rotation plane after the light source focal spot passes through the rotation center. After the CT system is designed, the central channel is often a determined value. However, due to errors in the mechanical precision of various components (such as machining, mechanical assembly, etc.), the position of the central channel deviates from the preset target position, and the position calculation of the central channel is inaccurate. The correction of the light source focal spot position and the mechanical position correction of the X-ray tube are both to adjust the central channel to the preset target position.

[0061] The correction method adopted in the related art is to scan an eccentric metal needle to obtain projection data, and after air correction, obtain the projection position at each angle, and then obtain their mean value in the rotation angle direction; this correction method requires the assumption that the angle variable is uniformly sampled when obtaining the projection position, that is, the angle segmentation when obtaining data should be uniform. However, this assumption does not hold in many CT systems, which will cause angle errors and lead to inaccurate calculation of the position of the central channel.

[0062] To solve the above problems, an embodiment of the present disclosure provides a method for determining the central channel position of multi-metal needle device scanning data, as follows Figure 1 As shown, the method includes the following steps S11 to S14:

[0063] Step S11: Design the phantom device as a multi-metal needle device, where the multi-metal needle device includes a plurality of straight metal needles that are parallel to each other in space, and the multi-metal needle device is used to correct the mechanical position of the CT system tube or correct the focal spot position of the light source;

[0064] By correcting the mechanical position of the CT system tube or the focal spot position of the light source, the central channel can be adjusted to a preset target position or an ideal position, which is convenient for obtaining an accurate central channel position.

[0065] In an alternative embodiment of the present disclosure, the number of metal needles in the multi-metal needle device is N, and N is an integer greater than or equal to 2;

[0066] When N is greater than 2, any straight line in the rotation acquisition plane cannot pass through three metal needles at the same time, and the three metal needles are not in the same plane.

[0067] The schematic diagram of the multi-metal needle device provided by the embodiment of the present disclosure is as follows Figure 2 As shown Figure 2 There are 3 metal needles in the middle, that is, N is 3, and the scanning plane, that is, the rotation acquisition plane, is also called the detector rotation plane.

[0068] [[ID='24']]Step S12: Scan the multi-metal needle device to obtain corresponding scanning data. When scanning, all the metal needles on the multi-metal needle device are perpendicular to the rotation acquisition plane of the CT system, where the scanning data includes multiple discrete trajectory curves corresponding to the multiple metal needles;

[0069] The scanning data corresponding to the multi-metal needle devices with four different numbers of metal needles provided by the embodiment of the present disclosure is as follows Figure 3 As shown Figure 3 (a) is the scanning data corresponding to the 2-metal needle device, Figure 3 (b) is the scanning data corresponding to the 3-metal needle device, Figure 3 (c) is the scanning data corresponding to the 4-metal needle device, Figure 3 (d) is the scanning data corresponding to the 6-metal needle device, where the horizontal axis is the rotation angle and the vertical axis is the detector channel;

[0070] Each metal needle corresponds to a discrete trajectory curve, and the discrete trajectory curve is a trajectory curve with a width. The intersection of any two discrete trajectory curves is not a single intersection point, but a spatially discrete intersection point group composed of multiple intersection points. Each intersection point group is a discretized point group in the common area where two discrete trajectory curves intersect. From Figure 3It can be seen that any two discretized trajectory curves have two intersection groups.

[0071] In an optional implementation manner of the present disclosure, a multi-metal needle device is scanned to obtain corresponding scan data, including:

[0072] Scanning the air when the multi-metal needle device is not placed to obtain air data P air (c, s, v);

[0073] Rotating and collecting the multi-metal needle device to obtain projection data P(c, s, v);

[0074] Using the air data, the projection data is corrected for air according to the following formula to obtain corrected data A(c, s, v):

[0075]

[0076] Calculating the mean value in the data layer direction of the corrected data according to the following formula to obtain a sinogram A(c, v);

[0077]

[0078] Wherein, c, s, and v are respectively a channel index, a layer index, and a projection angle index, and end is the total number of layer indexes.

[0079] The sinogram obtained by scanning the multi-metal needle device provided by the embodiment of the present disclosure is as Figure 4 shown, Figure 4 in which is the sinogram obtained by scanning a 3-metal needle device, wherein the horizontal axis is the rotation angle and the vertical axis is the detector channel.

[0080] Step S13: Identifying all intersection groups of all discretized trajectory curves, wherein any two discretized trajectory curves have two intersection groups, and each intersection group is a point group discretized in the common area where two discretized trajectory curves intersect;

[0081] In an optional implementation manner of the present disclosure, identifying all intersection groups of all discretized trajectory curves includes:

[0082] Determining the number T of intersection groups of all discretized trajectory curves according to the following formula:

[0083] T = N * (N - 1)

[0084] Wherein, N is the number of metal needles in the multi-metal needle device.

[0085] Scanning a multi-metal needle device with N metal needles to obtain corresponding scanning data. The scanning data includes N discretized trajectory curves corresponding to N metal needles. Each discretized trajectory curve is a sine curve, and the number of intersection point groups of the N sine curves is T. Among them, in the sinogram A(c,v), the intersection points of the sine curves corresponding to any two metal needles are the coincidence points of the projection positions of the two metal needles on the detector. As Figure 5 shown, two such coincidence points can be found in the projection angle, so it can be called a coincidence point pair. The channel index positions corresponding to this coincidence point pair are a pair of conjugate channels symmetric about the central channel (-α,+α).

[0086] Identifying the intersection points of the sine curves in the sinogram A(c,v) to determine the T intersection point groups of the N sine curves. The intersection point groups provided by the embodiments of the present disclosure are as Figure 6 shown, Figure 6 in which there are 6 intersection point groups of 3 sine curves. Among them, the horizontal axis is the rotation angle and the vertical axis is the detector channel.

[0087] Step S14: Determine the channel coordinate positions corresponding to each intersection point group, and determine the mean value of the channel coordinate positions corresponding to each intersection point group to obtain the central channel position.

[0088] The embodiments of the present disclosure can obtain an accurate central channel position without relying on the accuracy of the rotation angle position, accurately determine the mechanical position of the CT system tube or the focal spot position of the light source, and solve the problem that the mechanical accuracy has errors or angle errors in the related art, resulting in inaccurate calculation of the position of the central channel.

[0089] In an alternative embodiment of the present disclosure, determining the channel coordinate positions corresponding to each intersection point group includes:

[0090] Calculating the channel coordinate position Pos(t) of each intersection point group according to the following formula:

[0091]

[0092] where I(t) is the total number of pixel points corresponding to the t-th intersection point group in the sinogram, c(t,i) and v(t,i) are the channel index and projection angle index corresponding to the i-th pixel point of the t-th intersection point group respectively, A(c(t,i),v(t,i)) is the sinogram, t∈[1,T], and T is the number of intersection point groups of all discretized trajectory curves. The above formula for determining the channel coordinate positions corresponding to each intersection point group is the centroid weight method.

[0093] In a preferred embodiment of the present disclosure, determining the mean value of the channel coordinate positions corresponding to each intersection point group to obtain the central channel position includes:

[0094] Calculate the mean of the channel coordinate positions corresponding to the T intersection groups according to the following formula to obtain the central channel position:

[0095]

[0096] Among them, CenterChannelPos is the central channel position in the current state of the CT system.

[0097] Taking the number of metal needles N = 3 as an example, the flow effect diagram of the method for determining the central channel position of the scanning data of the multi-metal needle device is as Figure 7 shown, where the horizontal axis is the rotation angle and the vertical axis is the detector channel;

[0098] Scan the 3-metal needle device to obtain scanning data. The number of intersection groups T of the 3 discretized trajectory curves is T = N*(N - 1)=6. The channel coordinate position corresponding to each intersection group is the ordinate corresponding to each intersection group. The ordinates corresponding to the 6 intersection groups are y1, y2, y3, y4, y5 and y6 respectively. The mean of the channel coordinate positions corresponding to the 6 intersection groups is the mean of the ordinates corresponding to the 6 intersection groups Obtain the accurate central channel position.

[0099] From the above description, it can be seen that the present disclosure achieves the following technical effects:

[0100] Calibrating the mechanical position of the CT system tube or calibrating the focal spot position of the light source can adjust the central channel to the preset target position, which is convenient for obtaining an accurate central channel position;

[0101] Through the mean of the channel coordinate positions corresponding to each intersection group, an accurate central channel position can be obtained without relying on the accuracy of the rotation angle position, accurately determine the mechanical position of the CT system tube or the focal spot position of the light source, and solve the problem that the mechanical accuracy in the related technology has errors, resulting in inaccurate calculation of the position of the central channel.

[0102] It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order than here.

[0103] The embodiment of the present disclosure also provides a system for determining the central channel position of the scanning data of the multi-metal needle device for implementing the above method embodiment, as Figure 8 shown. The central channel position determination system 80 includes:

[0104] Design unit 81 is used to design the phantom device as a multi-metal needle device. The multi-metal needle device includes a plurality of straight metal needles that are parallel to each other in space. The multi-metal needle device is used to correct the mechanical position of the CT system tube or correct the focal spot position of the light source;

[0105] Scanning unit 82 is used to scan the multi-metal needle device to obtain corresponding scan data. When scanning, all the metal needles on the multi-metal needle device are perpendicular to the rotation acquisition plane of the CT system. The scan data includes a plurality of discrete trajectory curves corresponding to the metal needles;

[0106] Identification unit 83 is used to identify all the intersection point groups of all the discrete trajectory curves. Any two discrete trajectory curves have two intersection point groups, and each intersection point group is a discretized point group of the common area where the two discrete trajectory curves intersect; and

[0107] Determination unit 84 is used to determine the channel coordinate positions corresponding to each intersection point group and determine the mean value of the channel coordinate positions corresponding to each intersection point group to obtain the central channel position.

[0108] In an alternative embodiment of the present disclosure, the number of metal needles in the multi-metal needle device is N, and N is an integer greater than or equal to 2;

[0109] When N is greater than 2, any straight line in the rotation acquisition plane cannot pass through three metal needles at the same time, and the three metal needles are not in the same plane.

[0110] The specific ways of performing operations by each unit in the above system embodiment have been described in detail in the embodiment related to the method, and will not be elaborated here.

[0111] The embodiment of the present disclosure also provides an electronic device, as Figure 9 shown. The electronic device includes one or more processors 91 and a memory 92. Figure 9 Taking one processor 91 as an example.

[0112] The controller may further include: an input device 93 and an output device 94.

[0113] The processor 91, the memory 92, the input device 93 and the output device 94 may be connected through a bus or other means. Figure 9 Taking connection through a bus as an example.

[0114] The processor 91 may be a Central Processing Unit (CPU). The processor 91 may also be other general-purpose processors, Digital Signal Processors (DSPs), Application Specific Integrated Circuits (ASICs), Field-Programmable Gate Arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. chips, or combinations of the above types of chips. The general-purpose processor may be a microprocessor or any conventional processor.

[0115] The memory 92, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs, non-transitory computer-executable programs, and modules, such as the program instructions / modules corresponding to the control method in the embodiments of the present disclosure. The processor 91 executes various functional applications and data processing of the server by running the non-transitory software programs, instructions, and modules stored in the memory 92, that is, implements the method for determining the central channel position of the multi-metal needle device scan data in the above method embodiments.

[0116] The memory 92 may include a program storage area and a data storage area. Among them, the program storage area can store an operating system and application programs required for at least one function; the data storage area can store data created according to the use of the processing device of the server operation, etc. In addition, the memory 92 may include high-speed random access memory, and may also include non-transitory memory, such as at least one magnetic disk storage device, flash memory device, or other non-transitory solid-state storage devices. In some embodiments, the memory 92 may optionally include a memory remotely set relative to the processor 91, and these remote memories can be connected to the network connection device through a network. Examples of the above networks include, but are not limited to, the Internet, enterprise intranets, local area networks, mobile communication networks, and combinations thereof.

[0117] The input device 93 can receive input digital or character information, and generate key signal inputs related to user settings and function controls of the processing device of the server. The output device 94 may include display devices such as a display screen.

[0118] One or more modules are stored in the memory 92 and, when executed by one or more processors 91, execute the method as Figure 1 shown.

[0119] Those skilled in the art can understand that to implement all or part of the processes in the above method embodiments, it can be completed by instructing relevant hardware through a computer program. The program can be stored in a computer-readable storage medium. When the program is executed, it may include the processes in the above method embodiments. Among them, the storage medium can be a magnetic disk, an optical disc, a read-only memory (ROM for short), a random access memory (RAM for short), a flash memory (FM for short), a hard disk drive (HDD for short), or a solid-state drive (SSD for short), etc.; the storage medium can also include a combination of the above types of memories.

[0120] Although the embodiments of the present disclosure have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present disclosure, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for determining the central channel position of scanning data of a multi-metal needle device, characterized in that, Including: The phantom device is designed as a multi-metal needle device, where the multi-metal needle device includes a plurality of straight metal needles that are parallel to each other in space, and the multi-metal needle device is used to correct the mechanical position of the CT system tube or correct the focal spot position of the light source; Scanning the multi-metal needle device to obtain corresponding scan data. When scanning, all the metal needles on the multi-metal needle device are perpendicular to the rotational acquisition plane of the CT system. Among them, the scan data includes a plurality of discrete trajectory curves corresponding to the metal needles; Identifying all intersection point groups of all the discrete trajectory curves. Any two discrete trajectory curves have two intersection point groups, and each intersection point group is a discretized point group of the common area where the two discrete trajectory curves intersect; and Determining the channel coordinate positions corresponding to each intersection point group, and determining the mean value of the channel coordinate positions corresponding to each intersection point group to obtain the central channel position; Among them, the determining the channel coordinate positions corresponding to each intersection point group includes: Calculating the channel coordinate position Pos(t) of each intersection point group according to the following formula: Where I(t) is the total number of pixel points corresponding to the t-th intersection point group in the sinogram, c(t,i) and v(t,i) are respectively the channel index and the projection angle index corresponding to the i-th pixel point of the t-th intersection point group, A(c(t,i),v(t,i)) is the sinogram, t ∈ [1,T], and T is the number of intersection point groups of all the discrete trajectory curves.

2. The method according to claim 1, wherein The number of metal needles in the multi-metal needle device is N, and N is an integer greater than or equal to 2; When N is greater than 2, any straight line in the rotational acquisition plane cannot pass through three metal needles at the same time, and the three metal needles are not in the same plane.

3. The method according to claim 1, wherein The scanning the multi-metal needle device to obtain corresponding scan data includes: Scan the air when the multi-metal needle device is not placed to obtain air data P air (c, s, v); Rotating and acquiring the multi-metal needle device to obtain projection data P(c,s,v); Using air data to correct the projection data according to the following formula to obtain corrected data A(c,s,v): Calculating the mean value in the data layer direction of the corrected data according to the following formula to obtain the sinogram A(c,v); Where c, s, and v are respectively the channel index, the layer index, and the projection angle index, and end is the total number of layer indices.

4. The method according to claim 1, wherein The identifying all intersection point groups of all the discrete trajectory curves includes: Determining the number of intersection point groups T of all the discrete trajectory curves according to the following formula: T = N*(N - 1) Where N is the number of metal needles in the multi-metal needle device.

5. The method according to claim 1, wherein The determining the mean value of the channel coordinate positions corresponding to each intersection point group to obtain the central channel position includes: Calculating the mean value of the channel coordinate positions corresponding to T intersection point groups according to the following formula to obtain the central channel position: Where CenterChannelPos is the central channel position in the current state of the CT system.

6. A central channel position determination system for scanning data of a multi-metal needle device, characterized in that, Including: A design unit for designing the phantom device as a multi-metal needle device, where the multi-metal needle device includes a plurality of straight metal needles that are parallel to each other in space, and the multi-metal needle device is used to correct the mechanical position of the CT system tube or correct the focal spot position of the light source; A scanning unit for scanning the multi-metal needle device to obtain corresponding scanning data. When scanning, all the metal needles on the multi-metal needle device are perpendicular to the rotation acquisition plane of the CT system. The scanning data includes multiple discrete trajectory curves corresponding to the multiple metal needles. An identification unit for identifying all the intersection point groups of all the discrete trajectory curves. Any two discrete trajectory curves have two intersection point groups, and each intersection point group is a discretized point group of the common area where the two discrete trajectory curves intersect. A determination unit for determining the channel coordinate positions corresponding to each intersection point group and determining the mean value of the channel coordinate positions corresponding to each intersection point group to obtain the central channel position. Among them, determining the channel coordinate positions corresponding to each intersection point group includes: Calculating the channel coordinate position Pos(t) of each intersection point group according to the following formula: Where I(t) is the total number of pixel points corresponding to the t-th intersection point group in the sinogram, c(t,i) and v(t,i) are the channel index and projection angle index corresponding to the i-th pixel point of the t-th intersection point group respectively, A(c(t,i),v(t,i)) is the sinogram, t ∈ [1,T], and T is the number of intersection point groups of all the discrete trajectory curves.

7. The system according to claim 6, wherein The number of metal needles in the multi-metal needle device is N, and N is an integer greater than or equal to 2. When N is greater than 2, any straight line in the rotation acquisition plane cannot pass through three metal needles at the same time, and the three metal needles are not in the same plane.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing a computer to execute the method for determining the central channel position of the scanning data of the multi-metal needle device according to any one of claims 1 to 5.

9. An electronic device, characterized in that, The electronic device includes: at least one processor; and a memory communicatively connected to the at least one processor. The memory stores a computer program executable by the at least one processor. The computer program is executed by the at least one processor to cause the at least one processor to execute the method for determining the central channel position of the scanning data of the multi-metal needle device according to any one of claims 1 to 5.

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