Edge extraction edges based on Halcon learning_ image. Hdev routine

* Read the picture 
read_image (Image, 'fabrik')

* Edge extraction 
* Get the edge amplitude image and edge direction image 
edges_image (Image, ImaAmp, ImaDir, 'lanser2', 0.5, 'nms', 12, 22)

* Two valued 
threshold (ImaAmp, Edges, 1, 255)

* Extract the skeleton 
skeleton (Edges, Skeleton)

* Form a sub-pixel contour through the skeleton 
gen_contours_skeleton_xld (Skeleton, Contours, 1, 'filter')

* display picture 
dev_display (Image)

* Display color 
dev_set_colored (6)

* Show the outline 
dev_display (Contours)

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* Read the picture 
read_image (Image, 'fabrik')

* Edge extraction 
* Get the edge amplitude image and edge direction image 
edges_image (Image, ImaAmp, ImaDir, 'lanser2', 0.5, 'nms', 12, 22)

Edge amplitude image （ImaAmp）：

Edge direction image （ImaDir）：

* Two valued 
threshold (ImaAmp, Edges, 1, 255)

* Extract the skeleton 
skeleton (Edges, Skeleton)

* Form a sub-pixel contour through the skeleton 
gen_contours_skeleton_xld (Skeleton, Contours, 1, 'filter')

* display picture 
dev_display (Image)

* Display color 
dev_set_colored (6)

* Show the outline 
dev_display (Contours)

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edges_image(Image : ImaAmp, ImaDir : Filter, Alpha, NMS, Low, High : )：

Use Deriche, Lanser, Shen perhaps Canny Filter for image edge extraction

Parameters （ translate ）：

Image ： The input image

ImaAmp： Edge amplitude （ Gradient size ） Images

ImaDir ： Edge direction image

Filter： Edge operator

Alpha： Filter parameters , Small values result in strong smoothing , But less detail （canny Opposite operator ）

NMS： Non maximum inhibition （ Set to none, Indicates that this value is not required ）

Low： Lower threshold of hysteresis threshold operation （ If threshold setting is not required , Is a negative value ）

High ： Upper threshold of hysteresis threshold operation （ If threshold setting is not required , Is a negative value ）