opencv找轮廓线并绘制轮廓线

IplImage* bin = cvCloneImage( gray );cvAdaptiveThreshold( gray, bin, 255, CV_ADAPTIVE_THRESH_MEAN_C, 0, 101, 5 );cvDilate( bin, bin, 0, 1 );CvMemStorage* storage = cvCreateMemStorage(0);CvContourScanner cs = cvStartFindContours( bin, storage, sizeof(CvContour), CV_RETR_TREE, CV_CHAIN_APPROX_SIMPLE );CvSeq* sq = 0;int i = 1;do{sq=cvFindNextContour( cs );if ( sq == NULL )break;CvRect rect = cvContourBoundingRect( sq ); // 外接矩形double area = cvContourArea( sq );         // 轮廓线内区域面积cvDrawContours( img, sq, CV_RGB(255, 0, 0), CV_RGB(0, 255, 0), 2 ); // 绘制轮廓线i++;}while ( sq != 0 );sq = cvEndFindContours( &cs );cvReleaseMemStorage( &storage );