對於傾斜的車牌，我們必須用仿射變換，將車牌弄正，再進行識別。如圖
*定位orientation_region (regiontrans, phi)
area_center (regiontrans, area, row, column)
*仿射變換
vector_angle_to_rigid (row, column, phi, row, column, -0.1, hommat2d)
affine_trans_image (image666, imageaffintrans, hommat2d, 'constant', 'false')
affine_trans_region (regiontrans, regionaffinetrans, hommat2d, 'nearest_neighbor')
*擷取reduce_domain (imageaffintrans, regionaffinetrans, imagereduced)
*分割rgb1_to_gray (imagereduced, grayimage)
invert_image (grayimage, imageinvert1)
threshold (grayimage, regions1, 174, 231)
opening_rectangle1 (regions1, regionopening1, 5, 5)
fill_up (regionopening1, regionfillup1)
connection (regionfillup1, connectedregions1)
select_shape (connectedregions1, selectedregions, ['area','height','width'], 'and', [702.75,27.982,29.266], [1697.25,90.367,70.917])
sort_region (selectedregions, sortedregions, 'character', 'true', 'column')
read_ocr_class_mlp ('industrial_0-9a-z_norej.omc', ocrhandle)
do_ocr_multi_class_mlp (sortedregions, imageinvert1, ocrhandle, class, confidence)
參考程式基本類似，只是在二值化後多了union與膨脹操作，具體問題具體分析
參考：
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