CN103871107B - A kind of method for quantitative measuring of isosurface extraction precision - Google Patents

A kind of method for quantitative measuring of isosurface extraction precision Download PDF

Info

Publication number
CN103871107B
CN103871107B CN201410067145.3A CN201410067145A CN103871107B CN 103871107 B CN103871107 B CN 103871107B CN 201410067145 A CN201410067145 A CN 201410067145A CN 103871107 B CN103871107 B CN 103871107B
Authority
CN
China
Prior art keywords
point
isosurface extraction
sampled
quantitative measuring
isosurface
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CN201410067145.3A
Other languages
Chinese (zh)
Other versions
CN103871107A (en
Inventor
冯结青
王明
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Zhejiang University ZJU
Original Assignee
Zhejiang University ZJU
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Zhejiang University ZJU filed Critical Zhejiang University ZJU
Priority to CN201410067145.3A priority Critical patent/CN103871107B/en
Publication of CN103871107A publication Critical patent/CN103871107A/en
Application granted granted Critical
Publication of CN103871107B publication Critical patent/CN103871107B/en
Expired - Fee Related legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Landscapes

  • Analysing Materials By The Use Of Radiation (AREA)
  • Image Analysis (AREA)

Abstract

The invention discloses the method for quantitative measuring of a kind of isosurface extraction precision, by choosing several sampled point on tri patch in this method for quantitative measuring, calculate sampled point to the Euclidean distance of corresponding point in true curved surface, then according to the distance of sampled point Yu corresponding point, respectively using all sampled points in all tri patchs to the Euclidean distance maximum of corresponding corresponding point as maximum deviation degree, meansigma methods is as average departure degree, mean square deviation is as deviation fluctuating margin, thus accurate and multi-angle measurement obtains isosurface extraction precision.The method for quantitative measuring of the present invention efficiently solves the metric question of the deviation of isosurface extraction result, realizes quantitative measurement from qualitative analysis, facilitates user to select suitable isosurface extraction method according to described application scenario.And method for quantitative measuring realization itself with use isosurface extraction method, applied widely, can have the extraction accuracy of effective quantitative measurement all isosurface extraction method.

Description

A kind of method for quantitative measuring of isosurface extraction precision
Technical field
The present invention relates to computer graphics isosurface extraction field, be specifically related to a kind of isosurface extraction precision Method for quantitative measuring.
Background technology
For Three-dimensional calibration volume data or implicit function, contour surface refers to that its scalar value or functional value are a certain The set of the point of constant.By selecting different scalar value or functional value, different contour surfaces can be obtained, Thus contribute to visualizing and analyzing relevant volume data and implicit surface.Therefore, isosurface extraction is three Underlying issue in the application such as dimension scalar field data visualization, implicit surface show, three-dimension curved surface reconstruction. The main thought of isosurface extraction algorithm is: for Three-dimensional calibration volume data, it is common that by discrete voxel list Unit's set description;Implicit function is carried out spatial sampling, generates basic solid primitives unit;Then at basic solid primitives list Contour surface is approached with Linear Triangular dough sheet in Yuan.Marching tetrahedra algorithm (mobile tetrahedron, Mt algorithm) and marching cubes algorithm (marching cubes algorithm, mc algorithm) be two typical Isosurface extraction algorithm.
In mc algorithm, basic processing unit is cube.The basic thought of algorithm is in traversal volume mesh All voxels, judge the position relationship between 8 angle points of each voxel and true curved surface successively, then Connected into tri patch by finding intersection the connected mode according in the most given look-up table, thus obtain Expression is approached in this voxel in value face.Look-up table has 256 (=28) the most corresponding 256 kinds of situations of individual entry. The handling process of mt algorithm is similar with mc algorithm flow, first determines whether the position of 4 angle points and true curved surface Relation, utilizes linear interpolation or high order approximation method to obtain the intersection point of contour surface and voxel limit, then according to The intersection point tried to achieve is connected into tri patch by the look-up table of mt algorithm.The entry of the look-up table of mt algorithm has Article 16, (=24)。
Isosurface extraction be Three-dimensional calibration data visualization, implicit surface show, three-dimension curved surface reconstruction etc. Underlying issue in application.Substantially, discrete cube volume data is to initial body data or implicit function Three linear approximation represent, now the contour surface in each three linear cube is cubic algebra curved surface, and Mc algorithm acquired results is the linear approximation for this cubic algebra curved surface, therefore exists in mc algorithm The process of twice approximation;Discrete tetrahedron volume data is the linear approximation to initial body data or implicit function, Under the supposed premise of linear approximation, mt algorithm acquired results is accurate, therefore exists in mt algorithm Once approach.Obviously, in mc and mt algorithm, the sampling density of volume data or implicit function is the biggest, etc. The approximation accuracy in value face is the highest, but the triangular plate number produced is the most, the space of algorithm and time loss Also can increase accordingly;Vice versa.Therefore, the approximation accuracy of quantitative measurement both representativeness algorithms for Relevant science and engineer applied have important reference value.
In sum, all there is deviation in the extraction result of isosurface extraction algorithm, and deviation is essentially from two sides Face: (1) is to the linear of voxel cell or three linear hypothesis;(2) tri patch is used to approach in voxel cell Contour surface.At present, isosurface extraction algorithm is of a great variety, but passes judgment on and extract the achievement of result precision the most very Few.And only a small amount of extraction accuracy judgment criteria research all concentrates on the process of difference situation, extraction The qualitative aspects such as result difference on subjective vision.Therefore, industry lack one can quantitative measurement equivalent The judgment criteria of face extraction accuracy and the computational methods of correspondence.
Summary of the invention
For the deficiencies in the prior art, the present invention proposes the method for quantitative measuring of a kind of isosurface extraction precision.
The method for quantitative measuring of a kind of isosurface extraction precision, described isosurface extraction precision includes average inclined From degree, the fluctuating margin of deviation and maximum deviation degree, described method for quantitative measuring includes:
(1) on each tri patch obtained by the extraction of isosurface extraction algorithm, several samplings are uniformly taken Point;
(2) determine all sampled points corresponding point in true curved surface, and each sampled point is to corresponding point Euclidean distance;
(3) compare each sampled point and obtain the Euclidean of maximum to the size of the Euclidean distance of corresponding corresponding point Distance, calculates the meansigma methods of all sampled points of all tri patchs and the Euclidean distance of corresponding corresponding point and equal Variance, and using described meansigma methods as average departure degree, fluctuates width using described mean square deviation as deviation Degree, using maximum Euclidean distance as maximum deviation degree.
The method for quantitative measuring of the isosurface extraction precision of the present invention utilize the result of isosurface extraction to obtain Quantitative to contour surface extraction accuracy of tri patch and the distance of true curved surface.Calculating isosurface extraction obtains The distance of tri patch and true curved surface time, by choosing several sampled point on tri patch, meter Calculation sampled point is to the distance of corresponding point in true curved surface, then according to the Euclidean of sampled point with corresponding corresponding point Distance, by comparing the Euclidean distance that obtains maximum, (this distance is all result dough sheets obtained of extraction Forward direction Hausdorff distance to true curved surface) as maximum deviation degree, and calculate all Euclidean distances Meansigma methods and mean square deviation, respectively as maximum deviation degree, average departure degree and deviation fluctuating margin, from And accurately and the measurement of multi-angle obtains isosurface extraction precision, efficiently solve the inclined of isosurface extraction result The metric question of difference, achieves quantitative measurement from qualitative analysis, facilitates user according to described application scenario Select suitable isosurface extraction method.And method for quantitative measuring realization itself with use isosurface extraction side Method, applied widely, can there is the extraction accuracy of effective quantitative measurement all isosurface extraction method.
Hausdorff distance describes the spacing of two compact subsets in metric space, is widely used in such as geometry The fields such as modeling, Model Matching.Hausdorff distance has directivity, including forward direction Hausdorff distance and Backward Hausdorff distance.In prior art, extract result and (use the extraction of isosurface extraction algorithm to obtain The set of all tri patchs) in the forward direction Hausdorff distance of true curved surface according to formula:
d h ( S , D ) = max p ∈ S d ( p , D )
Being calculated, wherein S is for extracting result, and D is true curved surface, and p is the point in S, Represent the maximum in point all of in S to the Euclidean distance of true curved surface.These computational methods need traversal In extraction result, institute is a little, and each point is required for traveling through institute in D, and a little, therefore amount of calculation is very greatly, imitates Rate is low.The present invention directly utilizes the maximum approximation conduct in Euclidean distance between sampled point and true curved surface Three extraction results, to the forward direction Hausdorff distance of true curved surface, greatly reduce amount of calculation, are conducive to improving Measure efficiency.
In described step (2) corresponding point of each sampled point be in true curved surface with the Euclidean of this sampled point away from From minimum point.
How described step (2) is realized by optimized algorithm.
As preferably, described step (2) use interior point method determine that each sampled point is in true curved surface Corresponding point, and each sampled point is to the Euclidean distance of corresponding point.With other optimization method phases such as positive collection methods Ratio, interior point method is polynomial time algorithm, and solution efficiency is higher.
The sampled point number taken on each tri patch is identical.The sampled point taken in described step (1) For the intersection point between three summits of tri patch and the bisector on three bases being parallel to tri patch.
Sampled point has 3 three summits being tri patch, additionally, a part of intersection point is 2 bisectors Intersection point, part is the intersection point of 3 bisectors, and wherein the intersection point of 2 bisectors is positioned at the limit of tri patch On, the intersection point of 3 bisectors falls in tri patch.
Described bisector is n bisector, and wherein n is the natural number being not zero, and selects according to practical situation, When n=1 i.e. represents not decile, directly with three summits of tri patch as sampled point.Sampled point number is actual On depend on the value of n.The sampled point number taken on each tri patch is (n+1) × (n+2)/2.
The isodisperse of described bisector is 2~6.Isodisperse is the highest, then the number of sampled point is the most.Generally The most result of calculation of sampled point is the most accurate, but amount of calculation is relatively big, and efficiency is low, considers generally 2~6.
As preferably, the isodisperse of described bisector is 4.Consider the accurate of efficiency and result of calculation Degree, during usual triangle intersection point between 4 bisectors that sampled point is three bases being parallel to tri patch, I.e. one tri patch is sufficient for accuracy computation requirement when taking 15 sampled points.
The method for quantitative measuring of the isosurface extraction precision of the present invention utilize isosurface extraction result with true The distance of curved surface quantitatively, with multi-angle measure isosurface extraction algorithm precision, efficiently solve contour surface and carry Take the metric question of the deviation of result, realize quantitative measurement from qualitative analysis, facilitate user according to described Application scenario selects suitable isosurface extraction method.And method for quantitative measuring realization itself with use equivalence Face extracting method, applied widely, can there is the extraction essence of effective quantitative measurement all isosurface extraction method Degree.
Detailed description of the invention
Below in conjunction with detailed description of the invention, the method for quantitative measuring of the isosurface extraction precision of the present invention is entered Row describes in detail.
The method for quantitative measuring measurement utilizing this contour surface extraction accuracy in the present embodiment utilizes marching cube The extraction accuracy of the result of the isosurface extraction that algorithm (mc algorithm) completes, extracts the tri patch obtained Number be 2752.
The method for quantitative measuring medium value face extraction accuracy of the isosurface extraction precision of the present embodiment includes averagely Departure degree, the fluctuating margin of deviation and maximum deviation degree.
The method for quantitative measuring of the isosurface extraction precision of the present embodiment includes:
The method for quantitative measuring of a kind of isosurface extraction precision includes:
(1) on each tri patch obtained by the extraction of isosurface extraction algorithm, several samplings are uniformly taken Point, specific as follows:
With between three summits of tri patch and the n bisector on three bases being parallel to tri patch Intersection point is as the sampled point of this tri patch, and the sampled point number obtained is (n+1) × (n+2)/2, wherein n For the natural number being not zero.
N=4 in the present embodiment, i.e. with three summits and three bases being parallel to tri patch of tri patch Quarterline between intersection point as the sampled point of this tri patch.Obtain altogether 15 sampled points, its In 3 be three summits of tri patch, 9 is that the intersection point of two four bisectors (is positioned at tri patch Limit on), 3 is the intersection point (being positioned at tri patch) of three bisectors.
(2) determine all sampled points corresponding point in true curved surface, and each sampled point is to corresponding point Euclidean distance.
The present embodiment utilize interior point method determine this sampled point unique corresponding point in true curved surface respectively, so Rear calculating Euclidean distance between the two.The nonlinear optimal problem of this step actually belt restraining, its Solve relevant being provided that
Majorized function is the Euclidean distance formula between sample point and corresponding point, and constraints is true curved surface Toroidal function, initial point is sample point, the span of optimal solution be centered by sample point with voxel with Etc. the cubic space of size, the function value that the iterations in exit criteria is 100, optimal solution is corresponding It is 10-8, iteration ends step-length be 10-8
(3) compare each sampled point and obtain the Euclidean of maximum to the size of the Euclidean distance of corresponding corresponding point Distance, calculates the meansigma methods of all sampled points of all tri patchs and the Euclidean distance of corresponding corresponding point and equal Variance, and using described meansigma methods as average departure degree, fluctuates width using described mean square deviation as deviation Degree, using maximum Euclidean distance as maximum deviation degree.
In the present embodiment, kth tri patch is to the forward direction Hausdorff distance of true curved surfaceAccording to Formula:
d h k ( S , D ) ≈ max 1 ≤ i ≤ N d ( s i k , D )
Calculate, wherein:
N is the number of the sampled point on each tri patch, N=15 in the present embodiment,
For kth triangle unilateral on i-th (i=1,2 ... N) individual sampled point, S be extract obtain The set of all tri patchs, D is true curved surface, k=1,2 ... m, m are number (this of tri patch M=2752 in embodiment),
For sampled pointEuclidean distance (i.e. sampled point to true curved surface DWith true curved surface D In the Euclidean distance of corresponding point,It is right to representTake maximum.
The method maximum in all sampled points to the distance of true curved surface D should be used as tri patch mutually To the forward direction Hausdorff distance of true curved surface, the forward direction Hausdorff distance obtained is approximation.
Utilize formula:
d ‾ h ( S , D ) = 1 n s Σ i , k d ( s i k , D ) ,
Calculate the meansigma methods of each sampled point and the Euclidean distance of corresponding corresponding point, nsFor all tri patchs The sum of middle sampled point,Represent that traversal i and k is to allSummation.When isosurface extraction is calculated When method result dough sheet number is m, each tri patch takes 15 sample points, therefore one has 15 × m Sampled point, i.e. ns=15×m。
Utilize formula:
d v ( S , D ) = 1 n s Σ i , k ( d ( s i k , D ) - d ‾ h ( S , D ) ) 2
Calculate the mean square deviation of each sampled point and the Euclidean distance of corresponding corresponding point, Represent traversal i and k pairSummation.
The above, the only detailed description of the invention of the present invention, but protection scope of the present invention is not limited to This, any those familiar with the art, in the technical scope that the invention discloses, can readily occur in Change or replacement, all should contain within protection scope of the present invention.

Claims (6)

1. the method for quantitative measuring of an isosurface extraction precision, it is characterised in that described contour surface carries Take precision and include average departure degree, the fluctuating margin of deviation and maximum deviation degree, described quantitative measurement Method includes:
(1) on each tri patch obtained by the extraction of isosurface extraction algorithm, several samplings are uniformly taken Point;
(2) determine all sampled points corresponding point in true curved surface, and each sampled point is to corresponding point Euclidean distance;
(3) compare each sampled point and obtain the Euclidean of maximum to the size of the Euclidean distance of corresponding corresponding point Distance, calculates the meansigma methods of all sampled points of all tri patchs and the Euclidean distance of corresponding corresponding point and equal Variance, and using described meansigma methods as average departure degree, fluctuates width using described mean square deviation as deviation Degree, using maximum Euclidean distance as maximum deviation degree;
In described step (2) corresponding point of each sampled point be in true curved surface with the Euclidean of this sampled point away from From minimum point.
2. the method for quantitative measuring of isosurface extraction precision as claimed in claim 1, it is characterised in that Described step (2) use interior point method determine each sampled point corresponding point in true curved surface, and respectively Individual sampled point is to the Euclidean distance of corresponding point.
3. the method for quantitative measuring of isosurface extraction precision as claimed in claim 2, it is characterised in that The sampled point number taken on each tri patch is identical.
4. the method for quantitative measuring of isosurface extraction precision as claimed in claim 3, it is characterised in that Sampled point is tri patch three summits taken in described step (1) and be parallel to the three of tri patch Intersection point between the bisector on bar base.
5. the method for quantitative measuring of isosurface extraction precision as claimed in claim 4, it is characterised in that The isodisperse of described bisector is 2~6.
6. the method for quantitative measuring of isosurface extraction precision as claimed in claim 5, it is characterised in that The isodisperse of described bisector is 4.
CN201410067145.3A 2014-02-26 2014-02-26 A kind of method for quantitative measuring of isosurface extraction precision Expired - Fee Related CN103871107B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201410067145.3A CN103871107B (en) 2014-02-26 2014-02-26 A kind of method for quantitative measuring of isosurface extraction precision

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201410067145.3A CN103871107B (en) 2014-02-26 2014-02-26 A kind of method for quantitative measuring of isosurface extraction precision

Publications (2)

Publication Number Publication Date
CN103871107A CN103871107A (en) 2014-06-18
CN103871107B true CN103871107B (en) 2017-01-04

Family

ID=50909611

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201410067145.3A Expired - Fee Related CN103871107B (en) 2014-02-26 2014-02-26 A kind of method for quantitative measuring of isosurface extraction precision

Country Status (1)

Country Link
CN (1) CN103871107B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110610478B (en) * 2019-07-24 2021-05-25 浙江大学 Medical image three-dimensional reconstruction method based on neighborhood topology
CN111323148A (en) * 2020-03-06 2020-06-23 江苏省农业科学院 Greenhouse sensor arrangement method and system based on three-dimensional space

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101672637A (en) * 2009-09-24 2010-03-17 华东理工大学 Digitizing detection method of complicated curved face
CN101702237A (en) * 2009-11-10 2010-05-05 南京大学 Horizontal surface fitting method based on quadric error metrics (QEM)

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7324706B2 (en) * 2004-09-09 2008-01-29 Silicon Optix Inc. System and method for representing a general two dimensional spatial transformation

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101672637A (en) * 2009-09-24 2010-03-17 华东理工大学 Digitizing detection method of complicated curved face
CN101702237A (en) * 2009-11-10 2010-05-05 南京大学 Horizontal surface fitting method based on quadric error metrics (QEM)

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
MEASURING ERROR BETWEEN SIMILAR SURFACES;Kestutis Jankauskas 等;《Information Technology & Control》;20081231;第37卷(第3期);第198-204页 *
MESH:MEASURING ERRORS BETWEEN SURFACES USING THEHAUSDORFF DISTANCE;Nicolas Aspert 等;《Multimedia and Expo, 2002. ICME 02. Proceedings. 2002 IEEE International Conference on》;20021231(第1期);第705-708页 *

Also Published As

Publication number Publication date
CN103871107A (en) 2014-06-18

Similar Documents

Publication Publication Date Title
Portela et al. The turbulence cascade in the near wake of a square prism
CN109887015B (en) Point cloud automatic registration method based on local curved surface feature histogram
CN105654483B (en) The full-automatic method for registering of three-dimensional point cloud
Heinrich et al. Continuous parallel coordinates
CN104318622B (en) Triangular mesh modeling method of indoor scene inhomogeneous three dimension point cloud data
CN207095435U (en) A kind of slide measure
CN108319764A (en) Evaluation method for spatial straightness errors method based on longicorn palpus searching algorithm
CN105066915A (en) Mold curved surface machining error and surface roughness on-machine detection device and detection method
CN106646508A (en) Slope angle estimation method for slope region based on multiline laser radar
CN101856219A (en) Optical parameter reconstruction method based on frequency-domain near-infrared photoelasticimetry
CN108332685B (en) A kind of coding structural light three-dimensional measurement method
CN102920459A (en) Human body circumference parameter measuring method based on three-dimensional point cloud
CN103871107B (en) A kind of method for quantitative measuring of isosurface extraction precision
CN102663351A (en) Face characteristic point automation calibration method based on conditional appearance model
CN101937453B (en) 3-D model (three-dimensional model) search method based on weighted topology constraint comparison
CN106886980A (en) A kind of enhanced method of point cloud density based on three-dimensional laser radar target identification
CN103079269A (en) LDE (Linear Discriminant Analysis) algorithm-based WiFi (Wireless Fidelity) indoor locating method
CN106875439A (en) Silicon single crystal rod shape dimension measurement method based on three-dimensional point cloud model
CN106570338B (en) Method for determining sampling precision of contour line in roughness size effect of rock mass structural plane
Wang et al. A variational model for normal computation of point clouds
CN110763169B (en) Structure size measurement method based on central axis and central axis plane of reconstructed model
CN104993881A (en) Rapid analysis method of MIMO antenna mutual-coupling characteristic
CN106122430A (en) A kind of fine module gear rim detection accuracy computation method of feature based image
CN103488825B (en) A kind of data fitting method for gear-profile curve Reconstruction
CN101488190A (en) Computing method for similarity between vectors

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20170104

Termination date: 20210226

CF01 Termination of patent right due to non-payment of annual fee