[OpenCV] CV_16U to CV_8U

[0, 255] 범위를 넘어가는 value는 흰색, 검정색으로 나오기때문에
convertTo function에 범위를 재지정 해준다.

ex : A.convertTo(B,CV_8U,255.0/(Max-Min),-255.0/Min);

[Link]
Change type of Mat object from CV_32F to CV_8U
http://stackoverflow.com/questions/14539498/change-type-of-mat-object-from-cv-32f-to-cv-8u