从轮廓中取得四肢与头部的算法

从轮廓中取得四肢与头部的算法 实现了取得四肢与头部的算法，即取得五个U形的端点. 算法如下： int SegmentBody(CvSeq* contour) { float StandBodyLength = 10.0; float StandArc = 40; float lk,l1,l2=0; CvPoint pt1,pt2,pt0; double total_arc = 0; //内旋角度 double rarc12= 0; double arc12= 0; bool Haslkvec = false; //是否存在先前记录的矢量 CvSeqReader reader; CvSeqReader subReader; int N = contour->total; int i; CvPoint pt; CvPoint pre_pt; CvPoint pre_pre_pt; //CvFont font; //cvInitFont( &font, CV_FONT_HERSHEY_SIMPLEX, 0.3, 0.3, 0.0, 1, CV_AA ); cvStartReadSeq(contour, &reader); for (i= 0; i < N; i++) { CV_READ_SEQ_ELEM(pt, reader); //printf("%d,%d \n",pt.x,pt.y); pre_pt = pre_pre_pt = pt; //draw_cross( pt, CV_RGB(255,255,255), 3 ); if(i==9) draw_cross( pt, CV_RGB(240,222,240), 3 ); //cvLine( dst, pt,pre_pt,CV_RGB(0,255,0),2,CV_AA, 0 ); //计算两点之间的距离 subReader = reader ; Haslkvec = false; total_arc =0; //printf("------------------ \n"); //printf("%d,%d \n",pt.x,pt.y); for(int j=0;j<5;j++) { //printf("in sub %d,%d \n",pt.x,pt.y); l1=calc_2Point_Magnitude(pt,pre_pt); if (l1>StandBodyLength) { //是否存在先前记录的点，如果有，检查角度范围 if(Haslkvec) { Vector3f vt1 = Vector3f (pre_pre_pt.x-pre_pt.x,pre_pre_pt.y-pre_pt.y,0); Vector3f vt2 = Vector3f (pre_pt.x-pt.x,pre_pt.y-pt.y,0); arc12 = AngleBetweenVectors(vt1,vt2); rarc12 = 180*arc12/pi; Vector3f vtnor=Cross(vt1,vt2); //使用叉集检查矢量是内旋还是外旋。 if(vtnor.z >0) total_arc += rarc12; else total_arc -= rarc12; //检查角度范围合理 -200 -160 if (abs(total_arc+180)<StandArc) { //检查平行线之间构成四边形是否在同一轴线上，相似度判断 if(Is_Closed_Vectors(pt,pre_pt,pt1,pt2)) { //匹配成功，完成一个搜索 //记录两个矢量，清空标记 Haslkvec = false; total_arc = 0; //绘出位置 draw_2Points(pt,pre_pt,pt1,pt2); //跳过已经成形的点，好处是减少计算，二是避免歧异点 for(int k=0;k<j;k++) { CV_READ_SEQ_ELEM(pt, reader); pre_pt = pre_pre_pt = pt; } } //cvShowImage( "Components", dst ); //cvWaitKey(0); break; } } else { //记录两个点 pt1=pt; pt2=pre_pt; Haslkvec = true; } } //对于短线段忽略，并且跳过其检测点，将加快检测速度。 else { pt = pre_pt; pre_pt = pre_pre_pt; } pre_pre_pt = pre_pt; pre_pt= pt; CV_READ_SEQ_ELEM(pt, subReader); } } return 0; }