smallest_rectangle2smallest_rectangle2SmallestRectangle2SmallestRectangle2smallest_rectangle2 (算子名称)

名称

smallest_rectangle2smallest_rectangle2SmallestRectangle2SmallestRectangle2smallest_rectangle2 — Smallest surrounding rectangle with any orientation.

参数签名

smallest_rectangle2(区域 : : : Row, Column, Phi, Length1, Length2)

描述

该算子 smallest_rectangle2smallest_rectangle2SmallestRectangle2SmallestRectangle2SmallestRectangle2smallest_rectangle2 determines the smallest surrounding rectangle of a region, i.e., the rectangle with the smallest area of all rectangles containing the region. For this rectangle the center, the inclination and the two radii are calculated. The calculation of the rectangle is based on the center coordinates of the region pixels.

In the documentation of this chapter (Regions / Features), you can find an image illustrating regions which vary in the length and phi of their smallest surrounding rectangle.

The smallest surrounding rectangle of a region. Note that the calculation is based on the center coordinates of the region pixels.

该算子 is applied when, for example, the location of a scenery of several regions (e.g., printed text on a rectangular paper or in rectangular print (justified lines)) must be found. The parameters of smallest_rectangle2smallest_rectangle2SmallestRectangle2SmallestRectangle2SmallestRectangle2smallest_rectangle2 are chosen in such a way that they can be used directly as input for 该算子s disp_rectangle2disp_rectangle2DispRectangle2DispRectangle2DispRectangle2disp_rectangle2 and gen_rectangle2gen_rectangle2GenRectangle2GenRectangle2GenRectangle2gen_rectangle2.

If more than one region is passed in 区域区域区域区域区域区域 the results are stored in tuples, the index of a value in the tuple corresponding to the index of a region in the input. In case of empty region all parameters have the value 0.0 if no other behavior was set (see set_systemset_systemSetSystemSetSystemSetSystemset_system).

运行信息

多线程类型:可重入(与非独占操作符并行运行)。
多线程作用域:全局(可以从任何线程调用)。
在元组级别自动并行化。

参数表

区域区域区域区域区域区域 (input_object) region(-array) → object

Regions to be examined.

RowRowRowRowrowrow (output_control) rectangle2.center.y(-array) → (real)

Line index of the center.

ColumnColumnColumnColumncolumncolumn (output_control) rectangle2.center.x(-array) → (real)

Column index of the center.

PhiPhiPhiPhiphiphi (output_control) rectangle2.angle.rad(-array) → (real)

Orientation of the surrounding rectangle (arc measure)

Assertion: - pi / 2 < Phi && Phi <= pi / 2

Length1Length1Length1Length1length1length_1 (output_control) rectangle2.hwidth(-array) → (real)

First radius (half length) of the surrounding rectangle.

Assertion: Length1 >= 0.0

Length2Length2Length2Length2length2length_2 (output_control) rectangle2.hheight(-array) → (real)

Second radius (half width) of the surrounding rectangle.

Assertion: Length2 >= 0.0 && Length2 <= Length1

例程 (HDevelop)

read_image(Image,'fabrik')
regiongrowing(Image,Regions,5,5,6,100)
smallest_rectangle2(Regions,Row,Column,Phi,Length1,Length2)
gen_rectangle2(Rectangle,Row,Column,Phi,Length1,Length2)
dev_set_draw ('margin')
dev_display(Rectangle)

例程 (HDevelop)

read_image(Image,'fabrik')
regiongrowing(Image,Regions,5,5,6,100)
smallest_rectangle2(Regions,Row,Column,Phi,Length1,Length2)
gen_rectangle2(Rectangle,Row,Column,Phi,Length1,Length2)
dev_set_draw ('margin')
dev_display(Rectangle)

例程 (HDevelop)

read_image(Image,'fabrik')
regiongrowing(Image,Regions,5,5,6,100)
smallest_rectangle2(Regions,Row,Column,Phi,Length1,Length2)
gen_rectangle2(Rectangle,Row,Column,Phi,Length1,Length2)
dev_set_draw ('margin')
dev_display(Rectangle)

例程 (HDevelop)

read_image(Image,'fabrik')
regiongrowing(Image,Regions,5,5,6,100)
smallest_rectangle2(Regions,Row,Column,Phi,Length1,Length2)
gen_rectangle2(Rectangle,Row,Column,Phi,Length1,Length2)
dev_set_draw ('margin')
dev_display(Rectangle)

例程 (HDevelop)

read_image(Image,'fabrik')
regiongrowing(Image,Regions,5,5,6,100)
smallest_rectangle2(Regions,Row,Column,Phi,Length1,Length2)
gen_rectangle2(Rectangle,Row,Column,Phi,Length1,Length2)
dev_set_draw ('margin')
dev_display(Rectangle)

Complexity

If F is the area of the region and N is the number of supporting points of the convex hull, the runtime complexity is O(sqrt(F) + N^2).

结果

该算子 smallest_rectangle2smallest_rectangle2SmallestRectangle2SmallestRectangle2SmallestRectangle2smallest_rectangle2 返回值 2 ( H_MSG_TRUE) if the input is not empty. The behavior in case of empty input (no input regions available) is set via 该算子 set_system('no_object_result',<Result>)set_system("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)SetSystem("no_object_result",<Result>)set_system("no_object_result",<Result>). The behavior in case of empty region (the region is the empty set) is set via set_system('empty_region_result',<Result>)set_system("empty_region_result",<Result>)SetSystem("empty_region_result",<Result>)SetSystem("empty_region_result",<Result>)SetSystem("empty_region_result",<Result>)set_system("empty_region_result",<Result>). If necessary an exception is raised.

可能的前置算子

thresholdthresholdThresholdThresholdThresholdthreshold, regiongrowingregiongrowingRegiongrowingRegiongrowingRegiongrowingregiongrowing, connectionconnectionConnectionConnectionConnectionconnection, runlength_featuresrunlength_featuresRunlengthFeaturesRunlengthFeaturesRunlengthFeaturesrunlength_features

可能的后置算子

disp_rectangle2disp_rectangle2DispRectangle2DispRectangle2DispRectangle2disp_rectangle2, gen_rectangle2gen_rectangle2GenRectangle2GenRectangle2GenRectangle2gen_rectangle2

可替代算子

elliptic_axiselliptic_axisEllipticAxisEllipticAxisEllipticAxiselliptic_axis, smallest_rectangle1smallest_rectangle1SmallestRectangle1SmallestRectangle1SmallestRectangle1smallest_rectangle1

参考其它

smallest_circlesmallest_circleSmallestCircleSmallestCircleSmallestCirclesmallest_circle, set_shapeset_shapeSetShapeSetShapeSetShapeset_shape

模块

Foundation

算子列表