CN104161531B

CN104161531B - The acquisition methods at beam-defining clipper edge and device, X-ray equipment

Info

Publication number: CN104161531B
Application number: CN201410183202.4A
Authority: CN
Inventors: 胡扬; 牛杰; 周海华; 崔凯
Original assignee: Shanghai United Imaging Healthcare Co Ltd
Current assignee: Shanghai United Imaging Healthcare Co Ltd
Priority date: 2014-05-04
Filing date: 2014-05-04
Publication date: 2015-09-30
Anticipated expiration: 2034-05-04
Also published as: CN104161531A

Abstract

A kind of acquisition methods of beam-defining clipper edge and device, X-ray equipment, the acquisition methods at described beam-defining clipper edge, for obtaining the beam-defining clipper edge in image, comprise: detect the straightway edge in described image based on beam-defining clipper edge detection method, when the length at the longest straightway edge is more than or equal to first threshold: described in determining, the longest straightway edge is beam-defining clipper edge; Detect weak edge in the gradient image of described image to obtain the first image; Obtain the first straightway edge with the longest described straightway sides aligned parallel; Determine that length is more than or equal to Second Threshold, the the first straightway edge being less than or equal to the 3rd threshold value is beam-defining clipper edge, to determine in described first image with the longest described straightway edge-perpendicular and length is more than or equal to the 4th threshold value, the second straightway edge being less than or equal to the 5th threshold value is beam-defining clipper edge.Technical solution of the present invention improves the accuracy rate of beam-defining clipper rim detection, and adopts the complexity at the method acquisition beam-defining clipper edge low.

Description

The acquisition methods at beam-defining clipper edge and device, X-ray equipment

Technical field

The present invention relates to field of medical device, particularly a kind of acquisition methods of beam-defining clipper edge and device, X-ray equipment.

Background technology

Digital X-ray photography (DR, Digital Radiography) equipment is that computer digital image treatment technology combines with X-ray radiation technique and the armarium of a kind of advanced person that formed.Digital X-ray photographic equipment because its radiation dose is little, the quality of image is high, the accuracy of the recall rate of disease and diagnosis is higher and be widely used.

DR equipment mainly comprises: high tension generator, x-ray bulb, flat panel detector, beam-defining clipper, acquisition workstation etc.Beam-defining clipper, also referred to as light concentrator, chopper etc., is arranged on the cover window of x-ray bulb usually, removes former unnecessary x-ray for hiding in x-ray inspection.Roentgen radiation x open country can be limited in required minimum zone by it, and dosage patient being accepted roentgen radiation x reduces to minimum.

For Medical Image Processing and analysis, image Segmentation Technology plays a part key, Iamge Segmentation is the prerequisite of quantitative measurement, image registration, structural analysis, motion analysis, three-dimensional visualization, surgical navigational and treatment assessment etc., and it plays a part key in medical image analysis with process.Due to the complexity of human anatomic structure, the scrambling of histoorgan shape and interindividual diversity, so far, also there is not a general method and can be partitioned into each area-of-interest in image exactly.For the X-ray image having added beam-defining clipper, first need the region of accurately locating beam-defining clipper covering, tentatively to determine the position of area-of-interest, reduce the scope of search area-of-interest.And interference can be caused to the area-of-interest extracted in X-ray image in the region that beam-defining clipper covers, in addition, remove the image of beam-defining clipper overlay area, the accuracy rate to region of interesting extraction in X-ray image can be increased substantially, therefore, detection is carried out to beam-defining clipper edge most important.

Prior art adopts the method such as rim detection, straight-line detection to detect beam-defining clipper edge usually, but existing beam-defining clipper edge detection method does not consider that in actual photographic process, human body different parts is on the impact of beam-defining clipper rim detection, and then cause that the accuracy rate of beam-defining clipper rim detection is lower, false drop rate is higher.

Therefore, how the acquisition methods at the beam-defining clipper edge that a kind of accuracy rate is high can be provided, become one of current problem demanding prompt solution.

Summary of the invention

The problem to be solved in the present invention is to provide the high and acquisition methods at the beam-defining clipper edge that complexity is low of a kind of accuracy rate.

For solving the problem, technical solution of the present invention provides a kind of acquisition methods of beam-defining clipper edge, and for obtaining the beam-defining clipper edge in image, the acquisition methods at described beam-defining clipper edge comprises:

The straightway edge in described image is detected, when the length at the longest straightway edge is more than or equal to first threshold based on beam-defining clipper edge detection method:

Described in determining, the longest straightway edge is beam-defining clipper edge;

Detect weak edge in the gradient image of described image to obtain the first image;

Obtain the first straightway edge with the longest described straightway sides aligned parallel;

Determine that length is more than or equal to Second Threshold, the first straightway edge being less than or equal to the 3rd threshold value is beam-defining clipper edge, the length at the longest straightway edge described in described Second Threshold, the 3rd threshold value are associated with;

To determine in described first image with the longest described straightway edge-perpendicular and length is more than or equal to the 4th threshold value, the the second straightway edge being less than or equal to the 5th threshold value is beam-defining clipper edge, the distance described in described 4th threshold value, the 5th threshold value are associated with between the longest straightway edge and described first straightway edge;

The longest described straightway edge is horizontal direction, and described first threshold is associated with the wide of described image; The longest described straightway edge is vertical direction, and described first threshold is associated with the height of described image.

Optionally, the longest described straightway edge is horizontal direction, the scope of described first threshold be [0.8 × as, as] as described in the longest straightway edge be vertical direction, the scope of described first threshold is [0.8 × IH, IH], as for as described in image wide, IH is the height of described image.

Optionally, the first straightway edge of described acquisition and the longest described straightway sides aligned parallel comprises:

Search in the gradient image of described image the straightway edge whether existed with the longest described straightway sides aligned parallel;

If exist, then determine that with the straightway edge of the longest described straightway sides aligned parallel be the first straightway edge;

If do not exist, then in the presumptive area of described first image, search for the straightway edge with the longest described straightway sides aligned parallel, determine that with the straightway edge of the longest described straightway sides aligned parallel be the first straightway edge, presumptive area refers to the longest described straightway edge as axis of symmetry, be no more than the region of preset distance apart from the distance at the longest described straightway edge, described preset distance is associated with the size of beam-defining clipper opening.

Optionally, the longest described straightway edge is horizontal direction, the scope of described preset distance is [0.3 × IH, 0.4 × IH], the longest described straightway edge is vertical direction, the scope of described preset distance be [0.3 × as, 0.4 × as], as for as described in image wide, IH is the height of described image.

Optionally, the weak edge in the gradient image of the described image of described detection comprises to obtain the first image: carry out self-adaption binaryzation to obtain described first image to the gradient image of described image.

Optionally, the scope of described Second Threshold is [0.7 × L _mAX, L _mAX], the scope of described 3rd threshold value is [0.8 × L _mAX, L _mAX], L _mAXfor the length at the longest described straightway edge.

Optionally, the scope of described 4th threshold value is [0.7 × D, 0.9 × D], and the scope of described 5th threshold value is [0.9 × D, D], D for described in distance between the longest straightway edge and described first straightway edge.

Optionally, the acquisition methods at described beam-defining clipper edge, also comprises: when the length at the longest described straightway edge is less than described first threshold:

Determine that in the straightway edge that beam-defining clipper edge detection method detects, length is more than or equal to the straightway edge of the 6th threshold value, described 6th threshold value is associated with the minima of described figure image width and senior middle school;

When the number at the straightway edge being more than or equal to described 6th threshold value is different value, based on the position at the straightway edge detected to obtain beam-defining clipper edge.

Optionally, the straightway edge being more than or equal to described 6th threshold value is four articles of straightway edges, and the position at the described straightway edge based on detecting comprises to obtain beam-defining clipper edge:

Determine straightway edge parallel in described four straightway edges;

Judge that whether there is straight line section edge in described four straightway edges aligns with described image boundary, or judge in described parallel straightway edge, whether to there is the straightway edge forming one-sided beam-defining clipper edge;

If exist, then described four straightway edges are beam-defining clipper edge;

If all do not exist, then judge whether to exist in described four articles of straightway edges the 3rd straightway edge crossing with described parallel straightway edge-perpendicular;

If do not exist, then determine that described parallel straightway edge is beam-defining clipper edge;

If exist, then judge whether to exist in described four articles of straightway edges the 4th straightway edge crossing with any straightway edge-perpendicular in described parallel straightway edge;

If do not exist, then determine that described parallel straightway edge and described 3rd straightway edge are beam-defining clipper edge;

If exist, then judge whether the mid point at described 4th straightway edge is less than or equal to the 7th threshold value to the distance at described 3rd straightway edge and the difference of intersection point distance, described intersection point distance refers to described 3rd straightway edge and the distance between described 4th straightway edge and the intersection point of any straightway edges intersect in described parallel straightway edge, the scope of described 7th threshold value is [0,0.1 × d], d is described intersection point distance;

If be less than or equal to described 7th threshold value, then determine that described four straightway edges are beam-defining clipper edge, otherwise, then determine that described parallel straightway edge, described 3rd straightway edge are beam-defining clipper edge.

Optionally, the straightway edge being more than or equal to described 6th threshold value is three articles of straightway edges, and the position at the described straightway edge based on detecting comprises to obtain beam-defining clipper edge:

Determine straightway edge parallel in described three straightway edges;

Judge that whether there is straight line section edge in described three straightway edges aligns with described image boundary, or judge in described parallel straightway edge, whether to there is the straightway edge forming one-sided beam-defining clipper edge;

If exist, then described three straightway edges are beam-defining clipper edge;

If all do not exist, then judge whether to exist in described three articles of straightway edges the 5th straightway edge crossing with described parallel straightway edge-perpendicular;

If exist, then judge whether to exist in the straightway edge detected the 6th straightway edge crossing with any straightway edge-perpendicular in described parallel straightway edge;

If do not exist, then determine that described three straightway edges are beam-defining clipper edge;

If exist, then judge whether the mid point at described 6th straightway edge is less than or equal to the 8th threshold value to the distance at described 5th straightway edge and the difference of intersection point distance, described intersection point distance refers to described 5th straightway edge and the distance between described 6th straightway edge and the intersection point of any straightway edges intersect in described parallel straightway edge, the scope of described 8th threshold value is [0,0.1 × d], d is described intersection point distance;

If be less than or equal to described 8th threshold value, then determine that described three articles of straightway edges, described 6th straightway edge are beam-defining clipper edge, otherwise, then determine that described three straightway edges are beam-defining clipper edge.

Optionally, the straightway edge being more than or equal to described 6th threshold value is two articles of straightway edges, and the position at the described straightway edge based on detecting comprises to obtain beam-defining clipper edge:

Judge that whether described two straightway edges are parallel;

If parallel, then judge whether there is the straightway edge forming one-sided beam-defining clipper edge in two parallel straightway edges;

If exist, then determine that described two straightway edges are beam-defining clipper edge.

Optionally, judge that straightway edge aligns with described image boundary to comprise:

Judge whether the difference of the starting point at described straightway edge and the distance of terminal and described image boundary is less than or equal to the 9th threshold value, if so, then described straightway edge aligns with described image boundary;

Described straightway edge is horizontal direction, and the scope of described 9th threshold value is [0,0.1 × I _w]; Described straightway edge is vertical direction, and the scope of described 9th threshold value is [0,0.1 × I _h]; I _wwide for described image, I _hfor the height of described image.

Optionally, judge that whether there is the straightway edge forming one-sided beam-defining clipper edge in parallel straightway edge comprises:

Calculate the length at described parallel straightway edge;

Described parallel straightway edge is horizontal direction, and when the described length at parallel straightway edge and the wide difference of described image are less than or equal to the tenth threshold value, described parallel straightway edge is one-sided beam-defining clipper edge;

Described parallel straightway edge is vertical direction, and when the difference of the described length at parallel straightway edge and the height of described image is less than or equal to 11 threshold value, described parallel straightway edge is one-sided beam-defining clipper edge;

The scope of described tenth threshold value is (0,0.1 × I _w], the scope of described 11 threshold value is (0,0.1 × I _h], I _wwide for described image, I _hfor the height of described image.

For solving the problem, technical solution of the present invention also provides a kind of acquisition device of beam-defining clipper edge, and for obtaining the beam-defining clipper edge in image, the acquisition device at described beam-defining clipper edge comprises:

First detecting unit, for detecting the straightway edge in described image based on beam-defining clipper edge detection method;

First judging unit, for judging whether the longest straightway edge is more than or equal to first threshold;

First determining unit, for when described first judging unit exports as being, described in determining, the longest straightway edge is beam-defining clipper edge;

Second detecting unit, for when described first judging unit exports as being, detects weak edge in the gradient image of described image to obtain the first image;

First acquiring unit, for when described first judging unit exports as being, obtains the first straightway edge with the longest described straightway sides aligned parallel;

Second determining unit, for determining that length is more than or equal to Second Threshold, the first straightway edge being less than or equal to the 3rd threshold value is beam-defining clipper edge, the length at the longest straightway edge described in described Second Threshold, the 3rd threshold value are associated with;

3rd determining unit, for when described first judging unit exports as being, to determine in described first image with the longest described straightway edge-perpendicular and length is more than or equal to the 4th threshold value, the the second straightway edge being less than or equal to the 5th threshold value is beam-defining clipper edge, the distance described in described 4th threshold value, the 5th threshold value are associated with between the longest straightway edge and described first straightway edge;

Optionally, described first acquiring unit comprises:

First search unit, for search for described image gradient image in whether there is the straightway edge with the longest described straightway sides aligned parallel;

First determines subelement, during for searching the straightway edge with the longest described straightway sides aligned parallel at described first search unit, determines that with the straightway edge of the longest described straightway sides aligned parallel be the first straightway edge;

Second search unit, during for not searching the straightway edge with the longest described straightway sides aligned parallel at described first search unit, the straightway edge of search and the longest described straightway sides aligned parallel in the presumptive area of described first image; Presumptive area refers to that, with the longest described straightway edge for axis of symmetry, be no more than the region of preset distance apart from the distance at the longest described straightway edge, described preset distance is associated with the size of beam-defining clipper opening;

Second determines subelement, during for searching the straightway edge with the longest described straightway sides aligned parallel at described second search unit, determines that with the straightway edge of the longest described straightway sides aligned parallel be the first straightway edge.

Optionally, described second detecting unit comprises: binarization unit, for carrying out self-adaption binaryzation to the gradient image of described image to obtain described first image.

Optionally, the acquisition device at described beam-defining clipper edge also comprises: the 4th determining unit, for exporting as time no at described first judging unit, determine that in the straightway edge that beam-defining clipper edge detection method detects, length is more than or equal to the straightway edge of the 6th threshold value, described 6th threshold value is associated with the minima of described figure image width and senior middle school;

Second acquisition unit, for when the number at the straightway edge being more than or equal to described 6th threshold value is different value, based on the position at the straightway edge detected to obtain beam-defining clipper edge.

Optionally, the straightway edge being more than or equal to described 6th threshold value is four articles of straightway edges, and described second acquisition unit comprises:

5th determining unit, for determining straightway edge parallel in described four straightway edges;

Second judging unit, for judging that whether there is straight line section edge in described four straightway edges aligns with described image boundary;

Whether the 3rd judging unit, exist for judging the straightway edge forming one-sided beam-defining clipper edge in described parallel straightway edge;

6th determining unit, for when described second judging unit or described 3rd judging unit export as being, determines that described four straightway edges are beam-defining clipper edge;

4th judging unit, for exporting as time no at described second judging unit and described 3rd judging unit, judges whether to exist in described four articles of straightway edges the 3rd straightway edge crossing with described parallel straightway edge-perpendicular;

7th determining unit, for exporting as time no at described 4th judging unit, determines that described parallel straightway edge is beam-defining clipper edge;

5th judging unit, for when described 4th judging unit exports as being, judges whether to exist in described four articles of straightway edges the 4th straightway edge crossing with any straightway edge-perpendicular in described parallel straightway edge;

8th determining unit, for exporting as time no at described 5th judging unit, determines that described parallel straightway edge and described 3rd straightway edge are beam-defining clipper edge;

6th judging unit, for when described 5th judging unit exports as being, judge whether the mid point at described 4th straightway edge is less than or equal to the 7th threshold value to the distance at described 3rd straightway edge and the difference of intersection point distance, described intersection point distance refers to described 3rd straightway edge and the distance between described 4th straightway edge and the intersection point of any straightway edges intersect in described parallel straightway edge, the scope of described 7th threshold value is [0,0.1 × d], d is described intersection point distance;

9th determining unit, for when described 6th judging unit exports as being, determines that described four straightway edges are beam-defining clipper edge;

Tenth determining unit, for exporting as time no at described 6th judging unit, determines that described parallel straightway edge, described 3rd straightway edge are beam-defining clipper edge.

Optionally, the straightway edge being more than or equal to described 6th threshold value is three articles of straightway edges, and described second acquisition unit comprises:

11 determining unit, for determining straightway edge parallel in described three straightway edges;

7th judging unit, for judging that whether there is straight line section edge in described three straightway edges aligns with described image boundary;

Whether the 8th judging unit, exist for judging the straightway edge forming one-sided beam-defining clipper edge in described parallel straightway edge;

12 determining unit, for when described 7th judging unit or described 8th judging unit export as being, determines that described three straightway edges are beam-defining clipper edge;

9th judging unit, for exporting as time no at described 7th judging unit and described 8th judging unit, judges whether to exist in described three articles of straightway edges the 5th straightway edge crossing with described parallel straightway edge-perpendicular;

13 determining unit, for exporting as time no at described 9th judging unit, determines that described parallel straightway edge is beam-defining clipper edge;

Tenth judging unit, for when described 9th judging unit exports as being, judges whether to exist in the straightway edge that detects the 6th straightway edge crossing with any straightway edge-perpendicular in described parallel straightway edge;

14 determining unit, for exporting as time no at described tenth judging unit, determines that described three straightway edges are beam-defining clipper edge;

11 judging unit, for when described tenth judging unit exports as being, judge whether the mid point at described 6th straightway edge is less than or equal to the 8th threshold value to the distance at described 5th straightway edge and the difference of intersection point distance, described intersection point distance refers to described 5th straightway edge and the distance between described 6th straightway edge and the intersection point of any straightway edges intersect in described parallel straightway edge, the scope of described 8th threshold value is [0,0.1 × d], d is described intersection point distance;

15 determining unit, for when described 11 judging unit exports as being, determines that described three articles of straightway edges, described 6th straightway edge are beam-defining clipper edge;

16 determining unit, for exporting as time no at described 11 judging unit, determines that described three straightway edges are beam-defining clipper edge.

Optionally, the straightway edge being more than or equal to described 6th threshold value is two articles of straightway edges, and described second acquisition unit comprises:

12 judging unit, whether parallel for judging described two straightway edges;

13 judging unit, for when described 12 judging unit exports as being, judges whether there is the straightway edge forming one-sided beam-defining clipper edge in two parallel straightway edges;

17 determining unit, for when described 13 judging unit exports as being, determines that described two straightway edges are beam-defining clipper edge.

For solving the problem, technical solution of the present invention also provides a kind of X-ray equipment, comprising: the acquisition device at above-mentioned beam-defining clipper edge.

Compared with prior art, technical solution of the present invention has the following advantages:

Detect straightway edge based on beam-defining clipper edge detection method, when the length at the longest straightway edge is more than or equal to first threshold, determine that the longest straightway edge is beam-defining clipper edge; Detect weak edge in the gradient image of described image to obtain the first image, based on to the length at described first image cathetus section edge and determine beam-defining clipper edge with the position relationship at the longest described straightway edge.Because the straightway edge detected beam-defining clipper edge detection method has carried out further judgement to obtain beam-defining clipper edge, therefore improve the accuracy rate of beam-defining clipper rim detection to a great extent, and adopt the complexity at the method acquisition beam-defining clipper edge low.

Further, when the length at the longest described straightway edge is less than described first threshold, when being different value to the number at the straightway edge being more than or equal to the 6th threshold value, the position based on the straightway edge detected obtains beam-defining clipper edge.Owing to having carried out further judgement to determine beam-defining clipper edge to the position at the straightway edge detected, therefore, improve the accuracy rate of beam-defining clipper rim detection and complexity is low.

In addition, for the X-ray image of different parts, the longest straightway edge that beam-defining clipper edge detection method detects is different, and based on the longest straightway edge length difference so that adopt diverse ways judge whether the straightway edge that beam-defining clipper edge detection method detects is beam-defining clipper edge, can the beam-defining clipper edge of X-ray image of Obtaining Accurate different parts, there is very strong universality; And further reduce based on the mode that the difference of the length at the longest described straightway edge obtains beam-defining clipper edge respectively the complexity obtaining beam-defining clipper edge.

Accompanying drawing explanation

Fig. 1 is the schematic flow sheet of the acquisition methods at the beam-defining clipper edge that the embodiment of the present invention one provides;

Fig. 2 is the schematic flow sheet of the acquisition methods at the beam-defining clipper edge that the embodiment of the present invention two provides;

Fig. 3 is the length at the longest straightway edge when being less than described first threshold and detecting that the straightway edge being more than or equal to the 6th threshold value is four articles, obtains the schematic flow sheet at beam-defining clipper edge;

Fig. 4 is the length at the longest straightway edge when being less than described first threshold and detecting that the straightway edge being more than or equal to the 6th threshold value is three articles, obtains the schematic flow sheet at beam-defining clipper edge;

Fig. 5 is the length at the longest straightway edge when being less than described first threshold and detecting that the straightway edge being more than or equal to the 6th threshold value is two articles, obtains the schematic flow sheet at beam-defining clipper edge.

Detailed description of the invention

For enabling above-mentioned purpose of the present invention, feature and advantage more become apparent, and are described in detail the specific embodiment of the present invention below in conjunction with accompanying drawing.Set forth detail in the following description so that fully understand the present invention.But the present invention can be different from alternate manner described here to implement with multiple, those skilled in the art can when without prejudice to doing similar popularization when intension of the present invention.Therefore the present invention is not by the restriction of following public detailed description of the invention.

Just as described in the background art, when beam-defining clipper edge being detected in prior art, accuracy rate is lower, particularly, for photography collection to image in the unconspicuous situation of intensity contrast between the image of inner and outer, beam-defining clipper edge, the beam-defining clipper edge detected may be discontinuous straightway; And for the linear stronger position of the lumbar vertebra etc. of the human body of photography collection, the beam-defining clipper edge detected is not likely then real beam-defining clipper edge.Therefore, inventor proposes, and further judges the beam-defining clipper edge utilizing beam-defining clipper edge detection method to detect, and based on the testing result of beam-defining clipper edge detection method, adopts different judgment modes to obtain real beam-defining clipper edge.

Elaborate with the acquisition methods of specific embodiment to the beam-defining clipper edge of technical solution of the present invention below.

embodiment one

When adopting X-ray equipment to position photographies such as lumbar vertebras, the beam-defining clipper edge that beam-defining clipper edge detection method detects may not be real beam-defining clipper edge, this mainly because, when gathering the image at these positions, too much radiation is subject to for avoiding patient, the edge of beam-defining clipper can be positioned on human body, and then the beam-defining clipper edge causing employing beam-defining clipper edge detection method to detect is inaccurate.Below provide in this kind of station diagram picture gathered, obtain the method at correct beam-defining clipper edge.

Refer to Fig. 1, Fig. 1 is the schematic flow sheet of the acquisition methods at the beam-defining clipper edge that the embodiment of the present invention one provides.As shown in Figure 1: the acquisition methods at described beam-defining clipper edge, for obtaining the beam-defining clipper edge in image, comprising:

Step S10: detect the straightway edge in described image based on beam-defining clipper edge detection method;

Step S11: judge whether the length at the longest straightway edge is more than or equal to first threshold, the longest described straightway edge is horizontal direction, and described first threshold is associated with the wide of described image; The longest described straightway edge is vertical direction, and described first threshold is associated with the height of described image;

Step S12: described in determining, the longest straightway edge is beam-defining clipper edge;

Step S13: detect weak edge in the gradient image of described image to obtain the first image;

Step S14: obtain the first straightway edge with the longest described straightway sides aligned parallel;

Step S15: determine that length is more than or equal to Second Threshold, the first straightway edge being less than or equal to the 3rd threshold value is beam-defining clipper edge, the length at the longest straightway edge described in described Second Threshold, the 3rd threshold value are associated with;

Step S16: to determine in described first image with the longest described straightway edge-perpendicular and length is more than or equal to the 4th threshold value, the the second straightway edge being less than or equal to the 5th threshold value is beam-defining clipper edge, the distance described in described 4th threshold value, the 5th threshold value are associated with between the longest straightway edge and described first straightway edge.

In the present embodiment, first-selected execution step S10, detects the straightway edge in described image based on beam-defining clipper edge detection method.Particularly, gradient operator can be adopted, as: the gradient in Robert operator, PreWitt operator, Sobel operator, Canny operator or Laplace operator computed image, based on the gradient in described image, binaryzation is carried out to it, also namely binaryzation is carried out to obtain binary image to the gradient image of described image.Particularly, the gray value exactly gray value of pixel in described gradient image being more than or equal to the pixel of predetermined threshold value is set to 1, and the gray value that the gray value of pixel in described gradient image is less than the pixel of predetermined threshold value is set to 0.

Hough transform (Hough) or radon conversion are carried out to described binary image, for hough transform, then in Hough matrix, find out two groups of parallel straightway edges, and these two groups parallel straightway edges are orthogonal, two groups that obtain based on Hough matrix parallel straightway edges are the straightway edge detected.

Perform step S11, the length at the straightway edge detected in step S10 is judged, the longest straightway edge is found out in the gradient image of described image, and its length and first threshold are compared, when the length at the longest described straightway edge is more than or equal to first threshold, perform step S12 ~ S16.And during the difference of the direction at place, the longest straightway edge, the value of described first threshold is also different, particularly:

If the longest straightway edge detected is horizontal direction, then described first threshold is associated with the wide of described image; In the present embodiment, when the longest described straightway edge is horizontal direction, the scope of described first threshold is [0.8 × I _w, I _w], I _wwide for described image, described first threshold can be 0.93 × I _w.

If the longest straightway edge detected is vertical direction, then described first threshold is associated with the height of described image; In the present embodiment, when the longest described straightway edge is vertical direction, the scope of described first threshold is [0.8 × I _h, I _h] I _hfor the height of described image, concrete, described first threshold can be 0.9 × I _h.

Perform step S12, determine that the longest straightway edge detected is a beam-defining clipper edge.

Perform step S13, detect weak edge in the gradient image of described image to obtain the first image, described gradient image is when performing step S10, adopts the image that gradient operator obtains.In the present embodiment, especially by described gradient image being carried out to self-adaption binaryzation to strengthen the feature in described gradient image, and then detect the weak edge in described gradient image.

Particularly, calculate each pixel in described gradient image exactly and, in the second order gradient of predetermined neighborhood, then carry out thresholding process to the second order gradient of described pixel in predetermined neighborhood, in the present embodiment, described predetermined neighborhood can be rectangle, square.If described predetermined neighborhood is square, then the scope of the described square length of side can be [0.003 × I _w, 0.005 × I _w], wherein I _wwide for described image.In another embodiment, other weak edge detection method also can be adopted to detect the weak edge in the gradient image of described image.Carrying out the image after self-adaption binaryzation to described gradient image is described first image.

Perform step S14: obtain the first straightway edge with the longest described straightway sides aligned parallel;

Particularly, described first straightway edge is determined in the following way:

If exist, then determine with the straightway edge of the longest described straightway sides aligned parallel to be described first straightway edge.

If search for less than the straightway edge with the longest described straightway sides aligned parallel in the gradient image of described image, then in the presumptive area of described first image, again search for the straightway edge with the longest described straightway sides aligned parallel, determine that with the straightway edge of the longest described straightway sides aligned parallel be the first straightway edge, presumptive area refers to the longest described straightway edge as axis of symmetry, be no more than the region of preset distance apart from the distance at the longest described straightway edge, described preset distance is associated with the size of beam-defining clipper opening.

In the present embodiment, for shooting lumbar vertebra, the size of beam-defining clipper opening is greater than 6 inches × 6 inches usually, and now, if the longest described straightway edge is horizontal direction, the scope of described preset distance is [0.3 × I _h, 0.4 × I _h], if the longest described straightway edge is vertical direction, the scope of described preset distance is [0.3 × I _w, 0.4 × I _w], I _wwide for described image, I _hfor the height of described image.In the present embodiment, when the longest described straightway edge is horizontal direction, described preset distance can be 0.35 × I _h; When the longest described straightway edge is vertical direction, described preset distance can be 0.36 × I _w.

For the longest described straightway edge for vertical direction, if search in the gradient image of described image first less than the straightway edge with the longest described straightway sides aligned parallel, then in described first image with the longest described straightway edge for axis of symmetry, be no more than 0.36 × I in the distance apart from the longest described straightway edge _wsearch is continued in the region of individual pixel, also namely: with the longest described straightway edge for benchmark, about it, is all less than or equal to 0.36 × I apart from its distance _wsearch in the region of individual pixel.

If the longest described straightway edge is horizontal direction, when searching in the gradient image of described image less than straightway edge with the longest described straightway sides aligned parallel, be then in described first image with the longest described straightway edge for benchmark, thereon apart from its distance be all less than or equal to 0.35 × I _hsearch in the region of individual pixel.

In actual search process, if the longest straightway edge detected is horizontal direction and is positioned at image coboundary, then can with the longest described straightway edge for benchmark, to be positioned at below it and to be no more than 0.35 × I apart from it _hsearch in the region of individual pixel; If the longest straightway edge detected is vertical direction and is positioned at left picture boundary, then can with the longest described straightway edge for benchmark, to be positioned on the right side of it and to be no more than 0.36 × I apart from it _wsearch in the region of individual pixel.

Search with the first straightway edge of the longest described straightway sides aligned parallel after, perform step S15: the length at described first straightway edge is judged, if the length at described first straightway edge is more than or equal to described Second Threshold, be less than or equal to described 3rd threshold value, then described first straightway edge is beam-defining clipper edge.The length at the longest straightway edge described in second, third threshold value described is all associated with, the scope of wherein said Second Threshold is [0.7 × L _mAX, L _mAX], the scope of the 3rd threshold value is [0.8 × L _mAX, L _mAX], L _mAXfor the length at the longest described straightway edge.In the present embodiment, described Second Threshold can be 0.8 × L _mAX, described 3rd threshold value can be L _mAX.

Perform step S16: to determine in described first image with the longest described straightway edge-perpendicular and length is more than or equal to the 4th threshold value, the the second straightway edge being less than or equal to the 5th threshold value is beam-defining clipper edge, the distance described in described 4th threshold value, the 5th threshold value are associated with between the longest straightway edge and described first straightway edge.In the present embodiment, the scope of described 4th threshold value is [0.7 × D, 0.9 × D], and the scope of described 5th threshold value is [0.9 × D, D], D for described in distance between the longest straightway edge and described first straightway edge.Concrete, described 4th threshold value can be 0.8 × D, and described 5th threshold value can be D.

It should be noted that, obtain in the process at beam-defining clipper edge in reality, is to search the first straightway edge of meeting above-mentioned condition and the second straightway edge under normal circumstances.If in search procedure, do not search the first straightway edge with the longest described straightway sides aligned parallel, then can with the longest described straightway section sides aligned parallel and the image boundary relative with the longest described straightway edge comes polishing beam-defining clipper edge.For example, if the longest described straightway edge is close to the left margin of described image, then in parallel and relative image boundary is the right margin of described image.

If in search procedure, search the first straightway edge with the longest described straightway sides aligned parallel,

But the length at described first straightway edge is satisfied is more than or equal to described Second Threshold, be less than or equal to described 3rd threshold value, then with the image boundary polishing beam-defining clipper edge close with described first straightway edge, so-called closely to refer to: the angle β of the angle α of straightway edge and horizontal direction, image boundary and horizontal direction is satisfied: 0 °≤| alpha-beta |≤10 °.Same, if in search procedure, do not search the straightway edge with the longest described straightway edge-perpendicular, then can come polishing beam-defining clipper edge by the image boundary with the longest described straightway edge-perpendicular.

If in search procedure, search the straightway edge with the longest described straightway edge-perpendicular, but the length at this straightway edge is satisfied is more than or equal to described 4th threshold value, be less than or equal to described 5th threshold value, then with the image boundary polishing beam-defining clipper edge close with this straightway edge, described close same as described above, repeat no more herein.

By performing above-mentioned step S10 ~ S16, the beam-defining clipper edge in the more difficult images detecting beam-defining clipper edge such as lumbar vertebra can be obtained accurately, and the complexity performing above-mentioned steps acquisition beam-defining clipper is low, when practical application, can reduce the time of implementation of code.

embodiment two

In embodiment one, give the acquisition methods at the beam-defining clipper edge in the image obtained after being photographed in the positions such as lumbar vertebra, in the present embodiment, then main explanation is carried out to the acquisition at the beam-defining clipper edge in the image obtained after the photography of other positions.

Refer to Fig. 2, Fig. 2 is the schematic flow sheet of the acquisition methods at the beam-defining clipper edge that the embodiment of the present invention two provides.As shown in Figure 2, similar in wherein step S10 ~ S16 and embodiment one, repeat no more, when the length at the longest straightway edge is less than described first threshold, the acquisition methods at described beam-defining clipper edge comprises herein:

Step S17: determine that in the straightway edge that beam-defining clipper edge detection method detects, length is more than or equal to the straightway edge of the 6th threshold value, described 6th threshold value is associated with the minima of described figure image width and senior middle school.

Step S18: when the number at the straightway edge being more than or equal to described 6th threshold value is different value, based on the position at the straightway edge detected to obtain beam-defining clipper edge.

Perform step S17, judge whether the length at the straightway edge that beam-defining clipper edge detection method detects is more than or equal to described 6th threshold value, described in the present embodiment, the 6th threshold value is associated with the minima of described figure image width and senior middle school, the scope of described 6th threshold value can be [0.18 × L, 0.23 × L], wherein L is the minima of the wide of described image and senior middle school, as described in the 6th threshold value can be 0.2 × L pixel.

Perform step S18, for the straightway edge being more than or equal to described 6th threshold value in step S17, when the number at described straightway edge is different value, based on the position at the straightway edge detected to obtain beam-defining clipper edge.

Refer to Fig. 3, Fig. 3 is the length at the longest straightway edge when being less than described first threshold and detecting that the straightway edge being more than or equal to the 6th threshold value is four articles, obtains the schematic flow sheet at beam-defining clipper edge.As shown in Figure 3, the method obtaining beam-defining clipper edge comprises:

Step S1800: determine straightway edge parallel in described four straightway edges;

Step S1801: judge that whether there is straight line section edge in described four straightway edges aligns with described image boundary, or judge whether there is the straightway edge forming one-sided beam-defining clipper edge in described parallel straightway edge;

If exist, step S1802: determine that described four straightway edges are beam-defining clipper edge;

If all do not exist, step S1803: judge whether to exist in described four articles of straightway edges the 3rd straightway edge crossing with described parallel straightway edge-perpendicular;

If do not exist, step S1804: determine that described parallel straightway edge is beam-defining clipper edge;

If exist, step S1805: judge whether to exist in described four articles of straightway edges the 4th straightway edge crossing with any straightway edge-perpendicular in described parallel straightway edge;

If do not exist, step S1806: determine that described parallel straightway edge and described 3rd straightway edge are beam-defining clipper edge;

If exist, step S1807: judge whether the mid point at described 4th straightway edge is less than or equal to the 7th threshold value to the distance at described 3rd straightway edge and the difference of intersection point distance, described intersection point distance refers to described 3rd straightway edge and the distance between described 4th straightway edge and the intersection point of any straightway edges intersect in described parallel straightway edge, the scope of described 7th threshold value is [0,0.1 × d], d is described intersection point distance;

If be less than or equal to described 7th threshold value, step S1808: determine that described four straightway edges are beam-defining clipper edge;

If be greater than described 7th threshold value, step S1809: determine that described parallel straightway edge, described 3rd straightway edge are beam-defining clipper edge.

Perform step S1800, according to the straightway edge that the angle of four straightway edges and horizontal direction and then determine is parallel to each other in described four straightway edges.

Perform step S1801, judge that whether there is straight line section edge in described four straightway edges aligns with described image boundary; Particularly, judge in the following way

Judge whether the difference of the starting point at described straightway edge and the distance of terminal and described image boundary is less than or equal to the 9th threshold value, if so, then described straightway edge aligns with described image boundary.Particularly, described straightway edge is horizontal direction, and the scope of described 9th threshold value is [0,0.1 × I _w], described straightway edge is vertical direction, and the scope of described 9th threshold value is [0,0.1 × I _h]; Wherein: I _wwide for described image, I _hfor the height of described image.

In the present embodiment, when obtaining the distance of the starting point at described straightway edge and terminal and described image boundary, first need obtain starting point coordinate and the terminal point coordinate at described straightway edge.Particularly, the starting point coordinate at described straightway edge and terminal point coordinate can pass through the distance of this straightway edge and initial point and obtain with the angle of horizontal direction, the starting point coordinate and the terminal point coordinate that obtain described straightway edge are prior art, no longer describe in detail herein.In the present embodiment, when described straightway edge is horizontal direction, described 9th threshold value can be 0.05 × I _w, when described straightway edge is vertical direction, described 9th threshold value can be 0.06 × I _h.

Or, judge in described parallel straightway edge, whether to there is the straightway edge forming one-sided beam-defining clipper edge; Particularly, judge in the following way:

Calculate the length at described parallel straightway edge;

In the present embodiment, the length at described parallel straightway edge is in the process at detection of straight lines section edge, the distance between the Origin And Destination at this straightway edge, and when described parallel straightway edge is horizontal direction, described tenth threshold value can be 0.05 × I _w; When described parallel straightway edge is vertical direction, described 11 threshold value can be 0.05 × I _h.

Perform step S1802, if in the process performing step S1801, article four, there is straight line section edge in straightway edge to align with described image boundary, or there is the straightway edge forming one-sided beam-defining clipper edge in four parallel in straightway edge straightway edge, then these four straightway edges are beam-defining clipper edge.

If above-mentioned condition does not all meet, then perform step S1803, judge whether to exist in described four articles of straightway edges the 3rd straightway edge crossing with described parallel straightway edge-perpendicular.To judge between straightway edge whether vertically still to be determined by the difference of the angle of straightway edge and horizontal direction, no longer describe in detail herein.

If do not exist with described parallel straightway edge-perpendicular and crossing straightway edge, then perform step S1804, determine that described parallel straightway edge is beam-defining clipper edge.

If exist with described parallel straightway edge-perpendicular and crossing straightway edge, then perform step S1805, judge whether exist in four articles of straightway edges that beam-defining clipper edge detection method detects with any straightway edge-perpendicular in described parallel straightway edge and the 4th crossing straightway edge;

If there is not the 4th above-mentioned straightway edge, then perform step S1806, determine that described parallel straightway edge and described 3rd straightway edge are beam-defining clipper edge.

If there is the 4th above-mentioned straightway edge, then perform step S1807, judge whether the difference of distance between the mid point at described 4th straightway edge and described 3rd straightway edge and intersection point distance is less than or equal to the 7th threshold value; Described intersection point distance is described 3rd straightway edge and described 4th straightway edge and the distance between two intersection points during any straightway edges intersect in described parallel straightway edge.The scope of described 7th threshold value is [0,0.1 × d], and d is described intersection point distance, and the 7th threshold value described in the present embodiment can be 0.05 × d.

If be less than or equal to described 7th threshold value, then perform step S1808, determine that four the straightway edges detected are beam-defining clipper edge.

If be greater than described 7th threshold value, then perform step S1809, determine described parallel straightway edge and with described parallel straightway edge-perpendicular and the 3rd crossing straightway edge is beam-defining clipper edge.

It should be noted that, obtain in the process at beam-defining clipper edge in reality, for only determining in above-mentioned steps that two or three straightway edge is for the step at beam-defining clipper edge, step S1804 described above, S1806 and step S1809, now for step S1804, then can with two the image boundary polishing beam-defining clipper edges all vertical with described two parallel straightway edges.For step S1806, then can with the image boundary polishing beam-defining clipper edge relative with described 3rd straightway edge, for example, if described 3rd straightway edge is close to the left margin of described image, then relative with described 3rd straightway edge image boundary is then right margin, same, if described 3rd straightway edge is close to the coboundary of described image, then image boundary is corresponding thereto lower boundary.For step S1809, then can come polishing beam-defining clipper edge by the image boundary close with described 4th straightway edge.

To sum up, the beam-defining clipper edge performed in image when step S1800 ~ S1809 can be less than described first threshold to the length at straightway edge the longest in image and detect that the straightway edge being more than or equal to the 6th threshold value is four articles obtains.

In the process at actual acquisition beam-defining clipper edge, also may occur detecting that the straightway edge being more than or equal to the 6th threshold value is the situation of three articles or two articles, be described in detail respectively below by way of Fig. 4 and Fig. 5.

Refer to Fig. 4, Fig. 4 is the length at the longest straightway edge when being less than described first threshold and detecting that the straightway edge being more than or equal to the 6th threshold value is three articles, obtains the schematic flow sheet at beam-defining clipper edge;

Step S1810: determine straightway edge parallel in described three straightway edges;

Step S1811: judge that whether there is straight line section edge in described three straightway edges aligns with described image boundary, or judge whether there is the straightway edge forming one-sided beam-defining clipper edge in described parallel straightway edge;

If exist, step S1812: determine that described three straightway edges are beam-defining clipper edge;

If all do not exist, step S1813: judge whether to exist in described three articles of straightway edges the 5th straightway edge crossing with described parallel straightway edge-perpendicular;

If do not exist, step S1814: determine that described parallel straightway edge is beam-defining clipper edge;

If exist, step S1815: judge whether to exist in the straightway edge that detects the 6th straightway edge crossing with any straightway edge-perpendicular in described parallel straightway edge;

If do not exist, step S1816: determine that described three straightway edges are beam-defining clipper edge;

If exist, step S1817: judge whether the mid point at described 6th straightway edge is less than or equal to the 8th threshold value to the distance at described 5th straightway edge and the difference of intersection point distance, described intersection point distance refers to described 5th straightway edge and the distance between described 6th straightway edge and the intersection point of any straightway edges intersect in described parallel straightway edge, the scope of described 8th threshold value is [0,0.1 × d], d is described intersection point distance;

If be less than or equal to described 8th threshold value, step S1818: determine that described three articles of straightway edges, described 6th straightway edge are beam-defining clipper edge;

Otherwise, step S1819: determine that described three straightway edges are beam-defining clipper edge.

Perform step S1810, determine straightway edge parallel in three the straightway edges detected, namely according to the angle of described three straightway edges and horizontal direction and then determine straightway edge parallel in described three straightway edges.

Perform step S1811, judge how whether there is a straightway edge in three the straightway edges detected, specifically judge that straightway edge aligns see step S1801, can repeat no more with described image boundary herein if aliging with described image boundary.

Or, judge whether there is the straightway edge forming one-sided beam-defining clipper edge in the parallel straightway edge determined, how to judge that whether there is the straightway edge forming one-sided beam-defining clipper edge in parallel straightway edge see step S1801, can repeat no more herein.

If detect three in straightway edge, there is the straightway edge alignd with described image boundary, or there is the straightway edge forming one-sided beam-defining clipper edge, then perform step S1812, determine that described three straightway edges are beam-defining clipper edge.

Otherwise, perform step S1813, judge whether described three articles of straightway edges exist the 5th straightway edge with described parallel straightway edge-perpendicular and crossing.

If do not exist, perform step S1814, determine that described parallel straightway edge is beam-defining clipper edge.If exist, then perform step S1815, search in the straightway edge detected and whether exist with any straightway edge-perpendicular in described parallel straightway edge and the 6th crossing straightway edge; The length at described 6th straightway edge is less than described 6th threshold value.

If do not exist, perform step S1816, determine that the three articles of straightway edges being more than or equal to described 6th threshold value are beam-defining clipper edge.

If exist, perform step S1817, judge whether the difference between the mid point at described 6th straightway edge and the distance at described 5th straightway edge and described intersection point distance is less than or equal to the 8th threshold value, the distance between two intersection points when described intersection point distance then refers to described 5th straightway edge and described 6th straightway edge and any straight line section edges intersect in described parallel straightway edge; The scope of described 8th threshold value is [0,0.1 × d], and d is described intersection point distance, and in the present embodiment, described 8th threshold value can be 0.06 × d.

If the mid point at described 6th straightway edge is less than or equal to described 8th threshold value to the distance at described 5th straightway edge and the difference of described intersection point distance, then perform step S1818, determining that the three articles of length detected are more than or equal to the straightway edge that the straightway edge of described 6th threshold value and one article of length is less than described 6th threshold value is beam-defining clipper edge.

Otherwise, perform step S1819, determine that three articles of straightway edges that length is more than or equal to described 6th threshold value are beam-defining clipper edge.

It should be noted that, obtain in the process at beam-defining clipper edge in reality, for only determining in above-mentioned steps that two or three straightway edge is for the step at beam-defining clipper edge, step S1812 described above, S1814, S1816 and step S1819, now for step S1812 and S1816, then can with all vertical with the pair of parallel straightway edge in described three straightway edges and with the image boundary polishing beam-defining clipper edge of another straightway sides aligned parallel.For step S1814, then can with two the image boundary polishing beam-defining clipper edges all vertical with described parallel straightway edge.For step S1819, then can with the image boundary polishing beam-defining clipper edge close with described 6th straightway edge.

By performing above-mentioned steps S1810 ~ S1819, then the beam-defining clipper edge in image when can be less than described first threshold to the length at the longest straightway edge and detect that the straightway edge being more than or equal to described 6th threshold value is three articles obtains.

Refer to Fig. 5, Fig. 5 is the length at the longest straightway edge when being less than described first threshold and detecting that the straightway edge being more than or equal to the 6th threshold value is two articles, obtains the schematic flow sheet at beam-defining clipper edge.As shown in Figure 5, the method obtaining beam-defining clipper edge comprises:

Step S1820: judge that whether described two straightway edges are parallel;

If parallel, step S1821: judge whether there is the straightway edge forming one-sided beam-defining clipper edge in two parallel straightway edges;

If exist, step S1822: determine that described two straightway edges are beam-defining clipper edge.

Perform step S1820, judge that whether described two straightway edges are parallel based on described two straightway edges and the angle of horizontal direction;

If parallel, then perform step S1821, judge whether two parallel straightway edges form one-sided beam-defining clipper edge; Specifically how to judge whether parallel straightway edge forms one-sided beam-defining clipper edge see step S1801, repeats no more herein.

If so, then perform step S1822, two that determine to detect parallel straightway edges are beam-defining clipper edge.

It should be noted that, in above-mentioned steps, if occur, two straightway edges are not parallel, or parallel straightway edge is not the situation at one-sided beam-defining clipper edge, then with the image boundary polishing beam-defining clipper edge of described image, namely can replace beam-defining clipper edge by the image boundary of entire image.

By the method provided in embodiment two, the beam-defining clipper edge in the image obtained after can photographing to the position except the linear stronger position such as lumbar vertebra obtains, and the accuracy rate obtaining beam-defining clipper edge is higher, and complexity is low.

Corresponding to the acquisition methods at above-mentioned beam-defining clipper edge, technical solution of the present invention also provides a kind of acquisition device of beam-defining clipper edge, the acquisition device at described beam-defining clipper edge, for obtaining the beam-defining clipper edge in image, comprising:

The concrete enforcement of the acquisition device at described beam-defining clipper edge with reference to the enforcement of the acquisition methods at described beam-defining clipper edge, can not repeat them here.

Technical solution of the present invention also provides a kind of X-ray equipment, comprises the acquisition device at above-mentioned beam-defining clipper edge.

In sum, the acquisition methods at the beam-defining clipper edge that embodiment of the present invention provides and device, X-ray equipment, at least have following beneficial effect:

Further, when the length at the longest described straightway edge is less than described first threshold, when being different value to the number at the straightway edge being more than or equal to the 6th threshold value, position based on the straightway edge detected obtains beam-defining clipper edge, further determine beam-defining clipper edge by the judgement of the position to the straightway edge detected, improve the accuracy rate of beam-defining clipper rim detection and complexity is low.

In addition, for the X-ray image of different parts, the longest straightway edge that beam-defining clipper edge detection method detects is different, and based on the length at the longest straightway edge difference so that adopt diverse ways judge whether the straightway edge that beam-defining clipper edge detection method detects is beam-defining clipper edge, can the beam-defining clipper edge of X-ray image of Obtaining Accurate different parts, there is very strong universality; And further reduce based on the mode that the difference of the length at the longest described straightway edge obtains beam-defining clipper edge respectively the complexity obtaining beam-defining clipper edge.

Although the present invention with preferred embodiment openly as above; but it is not for limiting the present invention; any those skilled in the art without departing from the spirit and scope of the present invention; the Method and Technology content of above-mentioned announcement can be utilized to make possible variation and amendment to technical solution of the present invention; therefore; every content not departing from technical solution of the present invention; the any simple modification done above embodiment according to technical spirit of the present invention, equivalent variations and modification, all belong to the protection domain of technical solution of the present invention.

Claims

1. the acquisition methods at beam-defining clipper edge, for obtaining the beam-defining clipper edge in image, is characterized in that, comprise:

The longest described straightway edge is horizontal direction, and described first threshold is associated with the wide of described image; Or the longest described straightway edge is vertical direction, described first threshold is associated with the height of described image.

2. the acquisition methods at beam-defining clipper edge as claimed in claim 1, it is characterized in that, the longest described straightway edge is horizontal direction, and the scope of described first threshold is [0.8 × I _w, I _w], or the longest described straightway edge is vertical direction, the scope of described first threshold is [0.8 × I _h, I _h], I _wwide for described image, I _hfor the height of described image.

3. the acquisition methods at beam-defining clipper edge as claimed in claim 1, it is characterized in that, the first straightway edge of described acquisition and the longest described straightway sides aligned parallel comprises:

4. the acquisition methods at beam-defining clipper edge as claimed in claim 3, it is characterized in that, the longest described straightway edge is horizontal direction, and the scope of described preset distance is [0.3 × I _h, 0.4 × I _h], or the longest described straightway edge is vertical direction, the scope of described preset distance is [0.3 × I _w, 0.4 × I _w], I _wwide for described image, I _hfor the height of described image.

5. the acquisition methods at beam-defining clipper edge as claimed in claim 1, it is characterized in that, the weak edge in the gradient image of the described image of described detection comprises to obtain the first image: carry out self-adaption binaryzation to obtain described first image to the gradient image of described image.

6. the acquisition methods at beam-defining clipper edge as claimed in claim 1, it is characterized in that, the scope of described Second Threshold is [0.7 × L _mAX, L _mAX], the scope of described 3rd threshold value is [0.8 × L _mAX, L _mAX], L _mAXfor the length at the longest described straightway edge.

7. the acquisition methods at beam-defining clipper edge as claimed in claim 1, it is characterized in that, the scope of described 4th threshold value is [0.7 × D, 0.9 × D], the scope of described 5th threshold value is [0.9 × D, D], D for described in distance between the longest straightway edge and described first straightway edge.

8. the acquisition methods at beam-defining clipper edge as claimed in claim 1, is characterized in that, also comprise: when the length at the longest described straightway edge is less than described first threshold:

Being more than or equal to the number at straightway edge of described 6th threshold value for time different, based on the position at the straightway edge detected to obtain beam-defining clipper edge.

9. the acquisition methods at beam-defining clipper edge as claimed in claim 8, it is characterized in that, the straightway edge being more than or equal to described 6th threshold value is four articles of straightway edges, and the position at the described straightway edge based on detecting comprises to obtain beam-defining clipper edge:

Determine straightway edge parallel in described four straightway edges;

If exist, then described four straightway edges are beam-defining clipper edge;

10. the acquisition methods at beam-defining clipper edge as claimed in claim 8, it is characterized in that, the straightway edge being more than or equal to described 6th threshold value is three articles of straightway edges, and the position at the described straightway edge based on detecting comprises to obtain beam-defining clipper edge:

Determine straightway edge parallel in described three straightway edges;

The acquisition methods at 11. beam-defining clipper edges as claimed in claim 8, is characterized in that, the straightway edge being more than or equal to described 6th threshold value is two articles of straightway edges, and the position at the described straightway edge based on detecting comprises to obtain beam-defining clipper edge:

Judge that whether described two straightway edges are parallel;

The acquisition methods at 12. beam-defining clipper edges as described in any one of claim 9 to 10, is characterized in that, judge that straightway edge aligns with described image boundary and comprise:

Described straightway edge is horizontal direction, and the scope of described 9th threshold value is [0,0.1 × I _w]; Or described straightway edge is vertical direction, the scope of described 9th threshold value is [0,0.1 × I _h]; I _wwide for described image, I _hfor the height of described image.

The acquisition methods at 13. beam-defining clipper edges as described in any one of claim 9 to 11, is characterized in that, judge that whether there is the straightway edge forming one-sided beam-defining clipper edge in parallel straightway edge comprises:

Calculate the length at described parallel straightway edge;

The acquisition device at 14. 1 kinds of beam-defining clipper edges, for obtaining the beam-defining clipper edge in image, is characterized in that, comprise:

The acquisition device at 15. beam-defining clipper edges as claimed in claim 14, it is characterized in that, described first acquiring unit comprises:

The acquisition device at 16. beam-defining clipper edges as claimed in claim 14, it is characterized in that, described second detecting unit comprises:

Binarization unit, for carrying out self-adaption binaryzation to obtain described first image to the gradient image of described image.

The acquisition device at 17. beam-defining clipper edges as claimed in claim 14, is characterized in that, also comprise:

4th determining unit, for exporting as time no at described first judging unit, determine that in the straightway edge that beam-defining clipper edge detection method detects, length is more than or equal to the straightway edge of the 6th threshold value, described 6th threshold value is associated with the minima of described figure image width and senior middle school;

Second acquisition unit, for being more than or equal to the number at straightway edge of described 6th threshold value for time different, based on the position at the straightway edge detected to obtain beam-defining clipper edge.

The acquisition device at 18. beam-defining clipper edges as claimed in claim 17, is characterized in that, the straightway edge being more than or equal to described 6th threshold value is four articles of straightway edges, and described second acquisition unit comprises:

The acquisition device at 19. beam-defining clipper edges as claimed in claim 17, is characterized in that, the straightway edge being more than or equal to described 6th threshold value is three articles of straightway edges, and described second acquisition unit comprises:

The acquisition device at 20. beam-defining clipper edges as claimed in claim 17, is characterized in that, the straightway edge being more than or equal to described 6th threshold value is two articles of straightway edges, and described second acquisition unit comprises:

12 judging unit, whether parallel for judging described two straightway edges;

21. 1 kinds of X-ray equipment, is characterized in that, comprising: the acquisition device at the beam-defining clipper edge described in any one of claim 14 to 20.