android - "Moments" cannot be resolved to a type in opencv -

i have tried text extractor project using opencv tesseract library. while importing project added tesseract library. showing error in following of code.

moments moments = imgproc.moments(largest.get(0));         point center = new point(0,0);         center.x = moments.get_m10() / moments.get_m00();         center.y = moments.get_m01() / moments.get_m00();          list<point> points = largest.get(0).tolist();         points = sortcorners(points, center); 

error is

moments cannot resolved type