TWI307057B - A method for rendering three-dimension volume data - Google Patents

Description

1307057 IX. Description of the invention: [Technical field to which the invention pertains] The present invention is a method for displaying three-dimensional volume data, and more particularly, the present invention relates to a method for processing data using a square of a two-dimensional plane while utilizing sharp features to detect A method for displaying three-dimensional volume data by performing topographic extraction on a three-dimensional body = poor material. [Prior Art] In recent years, with the development of computergraphics technology, the application of scientific visualization has rapidly emerged, compared to the traditional use of a bunch of digital representations. Scientific visualization of the shape, color and image to present the content of the three-dimensional data makes it easier to be impressed and at a glance. With the rapid development of imaging technology, various imaging methods are used to obtain the required image information (such as computed tomography CT, nuclear magnetic resonance imaging MRI, positron tomography pET). For medicine, the understanding of the internal structure of the human body has received more and more attention. Some important information is often buried in medical images and cannot be observed by the naked eye. Thus, medical image processing has become a research field of 1 lang. Among them, for the processing of volume data, we can obtain the three-dimensional capital of each layer of human organs by computerized tomography, and then use the scientific visualization of computer graphics (C〇mPUter graphiCS) to make what we need. The model allows the physician to quickly and clearly understand the content of the 3D data. 6 • 1307057 The so-called volume data refers to the sampling data given to the regular spatial grid points, the source of which can be derived from the computerized tomography sweep. Computer tomography (CT), magnetic resonance imaging (MRI) or three-dimensional geometric shape transformation. Therefore, the volume data is a three-dimensional combination of many continuous two-dimensional images. Data, such as the use of computerized tomography to stratify the human skull, can obtain multiple continuous two-dimensional grayscale images, and then overlay these continuous images to form three-dimensional volume data, also known as data Set (dataset). The volume rendering technique is based on volumetric data in 3D. The definition in the middle, the three-dimensional data that is difficult to observe is presented as a two-dimensional image, so that the user can easily understand the content of the volume data, and because the object described by the volume data does not have a clear geometric description on the original data, There are two major categories in display technology: The first is direct volume rendering, such as ray casting, which is from every pixel in the image. Shooting in parallel projection and accumulating the contribution of the voxel through the ray to the color of the pixel, so the voxels of the entire volume data are usually used for entities with more ambiguous or deep information; and the other Indirect volume rendering, also known as surface approximation (surface 7 '1307057 fitting ), which uses triangles to attach to volume data, and then uses these triangles to depict objects. The surface, which is the 3D iso-surface extraction, is suitable for volume data. Obvious surface, such method is based on the Marching Cubes algorithm proposed by Lorensen and Cline (Lorensen WE, Cline Η. Ε.: Marching cubes: A high resolution 3d surface construction algorithm. In Proceedings of ACM SIGGRAPH (1987), Pp. 163-169, which contains two US patents: US4,710,876 and US4,719,585) is a pioneer in research and is also considered a standard method for solving isosurface extraction. The more common algorithm used today in 3D volumetric data is the marching cubes algorithm, which is also a very common algorithm for plotting equipotential surfaces or implicit function curves. The basic idea is to divide the space into cubes of equal size according to the space coordinates. Each vertex of each cube through the test space is replaced with a series of appropriate triangles for the corresponding case where the cube coordinates should be drawn. The result is a smooth surface that approximates the equipotential surface. However, the aforementioned marching cubes algorithm based on the analysis of space is based on two-dimensional cubes. The following problems have always existed in use. For example, the sharp features of objects cannot be preserved, and the topology information is incorrect or inconsistent. And multiple resolutions require crack patching. In addition, when the sharp features are retained, the above method will cause additional dependence (inter_eell 8 4307057 dependency) 〇•- As far as domestic research is concerned, most of them are medical images such as 'CT, MRI and ultrasound images. And the method of display, or the technique of two-dimensional stereo imaging, the method and characteristics of its implementation are still not separated. The above-mentioned marching cubes algorithm still has the same defects. In the above, since the technology of capturing three-dimensional volume data and the surface structure is still in shortcoming, the inventor has invented the case "displaying three-dimensional body information and information" in view of the above-mentioned lack of the prior art. Method."

L lean content J The main purpose of this case is to provide a method for displaying three-dimensional volume information, which transforms the original method of using a three-dimensional cube, and uses a two-dimensional plane to process three-dimensional volume information, thereby: The three-dimensional volume is displayed in a simple and fast manner; at the same time, the sharp features of the reconstructed object are achieved at the same time, and the topology information can be detected to detect the spatial non-interdependence, can be processed flatly and can be processed in the most subtle manner. Support multiple resolutions. The purpose of the present invention is to provide a three-dimensional volume data reconstruction in the three-dimensional space - the surface of the object: the following steps of the package 3 (4) segmentation of the three-dimensional space (8) to produce the same direction of the second-class recording of the ray and The number of intersections of the objects: 9 1307057 =: 2: Medium: Two of the complex points in each of the faces can be: Se_nt); (C) Get the positional state of the points, etc. The sampling point; (D) respectively calculate the sergeant, the sharp feature point; (E) the line segment of each single becomes the line segment ring (C〇mponent), and the 〇10 counts the 5 hai line segment The ring material stimulates & . γ ^, the points are each converted into a complex number: the corner piece t) = the relationship between the wire segment ring and its characteristics, the two corners Γ and (G) are in a space configuration. According to the above concept, the horns are combined to form a surface knot according to the above concept, and the ray systems are recorded in a vector manner according to the above-described configuration, according to the above-mentioned structure, the object is inside the object. The state of the fish in the two objects is based on whether it is based on the concept of the upper jaw. _ The normal vector of the two sampling points ^ the intersection point of the line segment to obtain the line segment::: a tangent line and according to the above two tangents, the step of dividing () is more included in all the faces Contains all the line segments within it. Open 3 = I think, the line segment in the step (D) is in the face type: fuzzy type 'where the simple fuzzy type wheel has the =::: line segment passed, and according to the above concept The fuzzy energy signature point and its corresponding sampling delay 10 1307057 are two configurations. The ring segment of the unit == 2 = two is formed by combining the segments. A line combination of the relationship and the head and tail connected to the ring == think that the triangle piece of the step (1) is generated by the U point of the line segment as the midpoint of the line segment ring in the line segment ring. The U and the two cooperate with the above-mentioned concept, and the side is composed of two points or a plurality of cedges including the same. U稷 number: According to the above concept, the face is surrounded by four edges (upper, lower,

Hbfa consists of or consists of several sub-faces contained within it. According to the above concept, the unit is composed of upper, lower and left meanings: a bidirectional face, or a sub-cell consisting of a plurality of sub-cells contained therein. Ding Pingyi method The purpose of this project is to provide a three-dimensional space for displaying three-dimensional volume data + reconstructing the surface structure of an object, 1 t = T: dividing the three-dimensional space to generate a complex point-to-Φ BianΜ#) and face (faCe) and unit (ceU); sample the object with two:=__; take the vector 'in which at least two sample points can form a line segment;: analyze the sample point through the mother-edge ,························································································· Point; and all the sampling points in the line segment ring with the line segment, the cold two-^ mouth on the convergence point to produce three = body:: ^ / (10) cents ^ ^ ^ combined to reconstruct More in-depth: the purpose, can be hunted by the following implementation,

The present invention is described below, and the description of the present invention is to be understood as being illustrative only and not limiting. Item 2 describes the three-dimensional volume method for the preferred embodiment of the present case, but the actual architecture and the method of adoption do not have to be described.

It! The structure and method of the description, the skilled person will be able to make various changes and modifications without departing from the actual (4) and scope of this issue.

Please refer to the first figure, which is a schematic flow chart of a method for displaying three-dimensional volume data disclosed in the present invention. The method of volumetric data of the present dimension can reconstruct the surface structure of the object through sampling and calculation in a three-dimensional space, which mainly divides the three-dimensional space in which the object is located to generate a complex point (voxel), An edge and a face and a cell (c(4)), in a two-dimensional array, generate a plurality of rays 1 in the same direction, and the rays respectively intersect with the object to form a plurality of sampling points ( Sample p〇int ), then in the direction of the ray in the form of a vector 12 '1307057 points, the information of all sampling points can be recorded in the shot can contain the following: its information 1. position; and 2 · normal vector. Two pairs are one ‘the line is in the ray, the sampling points are sorted according to their position order, group: two sampling points are representative—the continuous physical interval of the segment can be called a segment. -ft jc. iej γ

The line is sampled, that is, the scores arranged as shown in the first-graph-column * Γη are not where the dotted arrows represent the rays, the open circles represent the sampling points and the thick solid lines represent. Since 'the whole space belongs to the three-dimensional space' and the rays of each = are in the same direction', the case can be relied on: the front, the brake, and the three different directions to produce three identical rows. Thus, the points and edges that can be born are: 70's and the teeth are located in the three-dimensional object to generate a plurality of sampling points. Further, according to the above description, the form in the three-dimensional space can be composed of the following elements: Voxel or corner); 2. Edge, consisting of two points, or a number of sub-edges enclosed in "3" (face), surrounded by four The bottom, left, and right sides are composed of 'or consist of several _ sub-surfaces (sub_f prison); and 14 1307057 units (five). It consists of a face that surrounds six directions (up, down, left, and right) and is composed of several sub-cells. For a reconstructed two-dimensional object, its appearance can be composed of the following elements: ^ L sample point; 2 · sharp feature p〇int; 3. segment; and 4 segment segment ( Component). Columns: For the three-dimensional space sampled above, the 方法J method is used to reconstruct the appearance of the two-dimensional object: 1. All points are classified into two different types. Ships 2. Analyze all sides and calculate all the samples and points. Xin 3. Analyze all the faces, calculate all the segments included in them, and calculate the feature points of the segments. 4. Analyze all the units, connect all the line segments into line segments, and calculate the feature points of the line segments. 5. Convert all line segments and their feature points. In the third step above, in the third step above, the case (4) = use the five configurations listed in the figure to get all the line segments that may be included in the early side. 15 i3〇7〇57, and in the figure 'Configuration 0 (Case 0), configuration 1 (Case and group 2 (case 2) belong to simple type, and configuration 3 ^) is fuzzy State, wherein the simple type is the line in the face & or the only line segment passing through and the fuzzy form is the passage of two line segments in the face. But the fuzzy type will have the configuration 3 ι

3 · υ and configuration 3.2 (CaSe3.2) two possibilities, so the page is different. For this point, the case is to obtain two tangent lines through the normal vectors of the two sampling points on the side of the single line, and obtain the feature points of the line segment by the intersection of the two tangent lines, that is, as the fifth = no, Where v〇, V1, V2, and % represent points, respectively, the light-colored work core is the sampling point, the solid arrow is the tangent line, and the deep feature points. Therefore, by the above-mentioned detected feature points, the (four) feature points are then connected to the corresponding sample points through the two lines & Whether the extended line segments intersect can be classified into configuration 31 or group away from 3.2. If the two line segments have no phase (four), the self-time class of this type is the configuration. If the two line segments have intersections, the classification of such surfaces is A schematic diagram of the configuration in which there is a phase of the father is shown in the sixth figure. For the fourth step mentioned above, the case is to obtain the faces in the six directions of the upper and lower left and right of the 7L in the morning, and find the line segments in all the faces, and combine all the faces according to their spatial relationship. = The line segments connected at the beginning and the end are combined to form a line segment ring, and the conceptual form of forming a line segment ring and generating a line segment ring is shown in the schematic diagram of the seventh figure. 16 Ϊ 307057 In addition, regarding the generation of feature points of line segments, this paper uses the paper proposed by Kobbelt et al et al. (Kobbelt L_P., Botsch M., Schwanecke U., Seidel H.-P.: Feature sensitive surface extraction From Volume data. In Proceedings of ACM SIGGRAPH (2001), pp. 57-66·) is used to calculate the line segment feature points of this case. The summary of the operation is as follows: A plurality of sampling points are formed. If there are n+1 sampling points in the line segment ring, let s〇,...,sn be the sampling points in the line segment ring, and n〇,...,nn is the corresponding sampling The normal vector of the point, then: Calculate the maximum opening angle Θ in the normal vector with the expression Θ = min(/7 f ' ), and if the Θ system is less than a predefined value of 0sharp, then the line segment ring That is, it contains a feature point P. In general, the suggested value is 0sharp = 〇.9. In addition, suppose that point P is the characteristic point of the line segment ring. In theory, the point P will intersect with each plane formed by the sampling point and the normal vector. Therefore, the arithmetic expression: [...τν.·]7'; =[...the heart can get p point, which is the feature point of the line segment ring. Furthermore, in the fifth step, the feature point of the line segment ring is the midpoint, and all the sampling points in the line segment ring are matched with the corresponding feature points to generate a triangular piece, and the schematic diagram is as shown in the eighth figure. Shown. The resulting triangles are combined with each other according to relative spatial relationships to reconstruct the surface structure of the three-dimensional object. Therefore, the invention of the present invention proposes a new technique for displaying the three 17 ^ 1307057 dimension of the body 2 owing a shell. This new technology can simultaneously achieve the sharp η of the reconstructed object, retaining the topological information, and not Need to repair broken = support multiple resolutions. The invention of the present invention is basically compatible with the _hing cubes technology which is used to display volume information, and all applications related to volume information can be converted into use inventions. For example, medical image processing, three-two object restoration, virtual engraving, etc. Into one

As described above, τ', this case can indeed provide a method for displaying the three-dimensional volume λ, which changes the way of using the square, uses the plane of the plane, processes the data, and uses the sharp feature to detect the topology information and is simple. Quickly display 3D volume information, and at the same time achieve sharp features of reconstructed objects, sharp features for side topology, spatial non-dependency, parallel independent processing, and support for multiple resolutions in the most subtle way And the appearance that can be produced is the least error method in the current use of similar technology. Therefore, the method of displaying the three-dimensional volume data in this case is simple in technology, but it can provide a very high convenience for the ten students' and to effectively improve the progress of the industry. The technology of the present case is simple and can be applied in a wide range of fields, and the production value is 'in accordance with the law. patent application. The above description of the present invention will be described in detail by the preferred embodiments of the present invention, and is not to be construed as limiting the scope of the invention. Without departing from the spirit and scope of the present invention, it should be regarded as a further implementation of the present invention. I would like to ask your reviewer to clarify that it is a prayer. This case is familiar with this technology. The person who has been arbitrarily arbitrarily modified, but does not deviate from the scope of the patent application scope of the present application. Also ^ [Simple description of the schema] The concept of the three-dimensional volume point is shown in the preferred embodiment of the present invention. A schematic flow chart of a method for displaying data.

The second figure is the intention of sampling the ray record for this method.圃 局 局 本 本 本 本 本 本 本 本 本 本 本 本 本 本 本 本 本 本 本 本 本 本 本',' The fourth picture is a conceptual diagram of the various configurations on each side of the method in this case. Π-line & knife cloth Concept m is the feature point of the line segment of the method in this method. The sixth picture is a conceptual diagram of the method used for the configuration of this method. H, the difference in the seventh picture is the schematic diagram of each method in this case. The eighth figure that produces the line segment in the early days is the schematic diagram of the method in this case. Generating a corner piece [Major component symbol description] 19 1307057 101 Stepping space 102 step of generating a ray step 103 Recording a sample point step 104 Obtaining a sample point in each side Step 105 Obtaining a line segment in each side Step 106 Analysis line segment Step 107 of the type step of reconstructing the surface structure of the object by the step 109 of converting the line segment into a line segment and converting the step 108 into a triangular piece

Case 0 configuration 0

Case 1 configuration 1

Case 2 configuration 1

Case 3.1 Configuration 3.1

Case 3.2 Configuration 3.2 V point

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Claims (1)

1307057 Patent application scope ), 3⁄4 修正日修正1· A method of displaying three-dimensional volume data, by which a surface structure of an object is reconstructed in a three-dimensional space, the system comprising the following steps: (Α) dividing the three-dimensional space to generate a complex point (v 〇xel), edge, face, and cell; (B) generating complex rays in the same direction to record the plurality of sampling points at which the rays intersect with the object along the direction of the rays ( Sample point), wherein two of the plurality of sampling points in each of the faces form a segment; " (C) obtaining the positional state of the points and analyzing the sampling points included on each line; D) respectively calculate the feature points of the line segments; (E) connect all the line segments into a line segment component in each unit, and calculate the feature points of the line segment ring; Converting all of the line segments and their feature points into a plurality of triangles; and combining them to emphasize the surface structure of the objects according to a spatial relationship among the ray rays (G). 2. The method of claim 2, wherein the method is produced in a two-dimensional array. 3. The method of claim _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 4. The method of claim 2, wherein the position of the I 1307057 position is divided into two types, inner and outer, depending on whether it is located in the object. ', ', object, in which step (9) has two cut Hx and two cut H normal vectors to take the feature points of the segment. Get the line by the parent point of a tangent line. 6. If you want to apply for a special rhyme: = There are faces to analyze separately to take; ^: The mother-side contains all the line segments in it. 7. The method of claim 6, wherein the form of the line segment in the per-plane can be a single type and a fuzzy type. The knife is simplified. The method described in item 7 of the patent application is any one of the faces of the face. The heart has no line segment or only 9. The method state described in the application for patent application 7 is that there are two line segments in the face of the face = fuzzy type I. As in the scope of claim 9 The method described, the characteristics of the two lines of the political line and its corresponding heart: whether the extended line segments intersect and is divided into two groups. U. The method of claim 2, wherein the two-segment ring system is formed by combining all of the faces 2 of the unit: the heart At, the connected line segments, and the method described in the first patent. , in which 1307057 4 starts), the feature piece of the line segment is the midpoint of the line segment, and the sampling points in the ring of the ~, and the spring ring are combined with the characteristics of the line segment ring. The method of claim 1, wherein each of the sides is composed of two points, or a plurality of sub-edges are included in the plurality of sides. 4. The method of claim 1, wherein each of the faces is composed of edges enclosing four edges (up, down, left, and right), or a plurality of faces are included therein. The sub-face is composed of. 15. The method of claim 1, wherein each of the units is in the six directions of up, down, left, right, front, and back, or is comprised of a plurality of It consists of sub-cells inside. 16. A method of displaying three-dimensional volume data for reconstructing a surface structure of an object in a three-dimensional space, the method comprising the steps of: dividing the three-dimensional space to generate a complex point (v〇xei), an edge, and Face and cell; sample the object in a two-dimensional array of complex rays; record the sample points in vector form, at least two of which can form a line segment;: analyze the sample through each side Point; analyze the line segment configuration through each side; 1307057 respectively obtain all the line segments belonging to the face ^ in the upper, lower, left and right directions of each unit, and connect the line segments to become the line segment ring; calculate the feature points of the line segment ring And the feature point of the line segment is the midpoint, and all the sampling points in the line segment are matched with the feature points to generate a triangular piece, and then the plurality of triangular pieces are combined by a spatial relationship to reconstruct the surface of the object. Structure. And mouth