Once the CAD scheme is optimized, to process a digital image, {HEAD ~ an image characteristics based classification criteria} is established for {TAIL ~ that image}, and then global image features of the digitized image are determined 
is established for
Once the CAD scheme is optimized , to process a digital image , { HEAD ~ an image characteristics based classification criteria } is established for { TAIL ~ that image } , and then global image features of the digitized image are determined
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