Halcon: discrete digital OCR recognition

* Function of the scatter character OCR distinguish 
dev_clear_window ()
dev_open_window (0, 0, 640, 400, 'black', WindowHandle)
*1. Read images 
read_image (Image, 'E:/03 CV（ ancient ）/Halcon/ Code / Superman enlightenment _ Topic enlightenment /OCR_SVM/ Images /1.bmp')
get_image_size (Image, Width, Height)
*2. Location and affine transformation 
Classes:=['2','0','1','6','0','6','1','6','6','F','1','6','C','1','8','3','8','C']
Row1:=64.3375
Column1:=165.313
Row2:=218.713
Column2:=618.988
Px:=Column1+(Column2-Column1)/2
Py:=Row1+(Row2-Row1)/2
gen_rectangle1 (Rectangle,Row1,Column1,Row2,Column2 )
dev_display (Image)
dev_display (Rectangle)
* Affine transformation 
text_line_orientation (Rectangle, Image, 25, -0.523599, 0.523599, OrientationAngle)# Will be based on gen_rectangle1 (Rectangle,,, ) Medium Rectangle Automatically obtain the rotation angle OrientationAngle
hom_mat2d_identity (HomMat2DIdentity)
hom_mat2d_rotate (HomMat2DIdentity, -OrientationAngle, Px, Py, HomMat2DRotate)
affine_trans_image (Image, ImageAffineTrans, HomMat2DRotate, 'constant', 'false')
dev_display (Image)
dev_display (ImageAffineTrans)
*3. Dot extraction ( Dark spot )
dots_image (ImageAffineTrans, DotImage, 3, 'dark', 2)
gen_rectangle1 (ROI_0, 97.6825, 204.763, 205.128, 605.427)
reduce_domain (DotImage, ROI_0, ImageReduced)# tailoring （ The affine transformed image and the manual rectangular drawing area are cropped ）
threshold (ImageReduced, Regions, 60, 255)# Manual binarization （ It is necessary to set the threshold value √, The channel is changed to 1）
connection (Regions, ConnectedRegions)
select_shape (ConnectedRegions, SelectedRegions, 'area', 'and', 0, 50)
union1 (SelectedRegions, RegionUnion)
* Connect the scattered points of each number into a completely closed connected domain （ In the direction of expansion ： The longitudinal --> The transverse -->45° Oblique -->145° Oblique ）
closing_rectangle1 (RegionUnion, RegionClosing1, 1, 5)
closing_rectangle1 (RegionClosing1, RegionClosing2, 5, 1)
* Oblique expansion ： High set to 0
gen_rectangle2 (ROI_0, 16, 16, rad(45), 3, 0)
closing (RegionClosing2, ROI_0, RegionClosing3)

gen_rectangle2 (ROI_0, 2, 2, rad(145), 2, 0)
closing (RegionClosing3, ROI_0, RegionClosing4)
dilation_circle (RegionClosing4, RegionDilation, 1)

connection (RegionDilation, ConnectedRegions1)
select_shape (ConnectedRegions1, SelectedRegions1, 'area', 'and', 145.41, 433.49)# Remove the colon ：
partition_dynamic (SelectedRegions1, Partitioned, 30, 20)# Divide the area horizontally where the vertical range is small ), Prevent adhesion after corrosion and expansion 
sort_region (Partitioned, SortedRegions, 'character', 'true', 'row')# Reading mode and direction 
count_obj (SortedRegions, Number)

dev_display (ImageAffineTrans)
for i := 1 to Number by 1
    dev_set_color ('red')
    select_obj (SortedRegions, char, i)
    dev_display (char)
    intersection (char, Regions, RegionIntersection)# Extract the original figure number ： Extract the connected numbers of the scatter graph and make the intersection with the original scatter graph , Get the public part 
    append_ocr_trainf (RegionIntersection, ImageAffineTrans, Classes[i-1], 'D:/svm.trf') 
endfor