houghbianhuan.rar_hough_hough 变换_hough变换

/* ********Hough变化*************** * 该函数实现霍夫变换，按照直线在变换 * 空间的代数关系 r = x cos(p) + y sin(p), * 将直线变换成变换域的点（r，p） * 本函数找出图像中两条平行线 **********************************/ void CImageProcess::bmp_HoughTransform(CDib *pB) { //循环变量 int i,j; //象素取值 int pixel; //变换域的尺寸 int MaxDist; int MaxAngleNumber ; //获取原图像的大小和保存大小 CSize Dimensions,SaveSize; Dimensions = pB->GetDimensions(); SaveSize = pB->GetDibSaveDim(); //变换域最大值,坐标取值范围 MaxDist = (int) sqrt(SaveSize.cx *SaveSize.cx + SaveSize.cy * SaveSize.cy); MaxAngleNumber = 90; //变换域的坐标 int Dist; int AngleNumber; //存储变换域中的两个最大值 MaxValue MaxValue1 ; MaxValue MaxValue2 ; BYTE *pSrc,*pDest; if(pNewData) delete pNewData; pNewData = new byte[SaveSize.cx * SaveSize.cy]; memset( pNewData,0,SaveSize.cx * SaveSize.cy); if(pData) delete pData; pData = new byte[SaveSize.cx * SaveSize.cy]; // memset( pData,255,SaveSize.cx * SaveSize.cy); memcpy( pData,pB->m_lpImage,SaveSize.cx * SaveSize.cy); for(i = 0;i <Dimensions.cy ;i++) for(j = 0;j <Dimensions.cx; j++) { //处理256彩色图像 if(pB->m_lpBMIH->biBitCount ==8) ///////////////////////////////// pSrc = pB->m_lpImage + i*SaveSize.cx + j; //24位真彩色图像 else pSrc = pB->m_lpImage + i*SaveSize.cx + 3*j; pixel = *pSrc; //如果是黑点，则在变换域的对应各点上加1 if(pixel == 0) { //注意步长是2度 for(AngleNumber=0; AngleNumber<MaxAngleNumber; AngleNumber++) { Dist = (int) fabs(j*cos(AngleNumber*2*pi/180.0) + \ i*sin(AngleNumber*2*pi/180.0)); //变换域的对应点上加1 pDest = pNewData + Dist*MaxAngleNumber+AngleNumber; *pDest =*pDest + 1; } } } //找到变换域中的两个最大值点 MaxValue1.Value=0; MaxValue2.Value=0; //找到第一个最大值点 for (Dist=0; Dist<MaxDist;Dist++) { for(AngleNumber=0; AngleNumber<MaxAngleNumber; AngleNumber++) { if((int)*(pNewData+Dist*MaxAngleNumber+AngleNumber)>MaxValue1.Value) { MaxValue1.Value = (int)*(pNewData+Dist*MaxAngleNumber+AngleNumber); MaxValue1.Dist = Dist; MaxValue1.AngleNumber = AngleNumber; } } } //将第一个最大值点附近清零,为寻找第二个最大值点做准备 for (Dist = -9;Dist < 10;Dist++) { for(AngleNumber=-1; AngleNumber<2; AngleNumber++) { if(Dist+MaxValue1.Dist>=0 && Dist+MaxValue1.Dist<MaxDist && AngleNumber+MaxValue1.AngleNumber>=0 && AngleNumber +MaxValue1.AngleNumber<=MaxAngleNumber) { *(pNewData+(Dist+MaxValue1.Dist)*MaxAngleNumber+ (AngleNumber+MaxValue1.AngleNumber))=0; } } } //找到第二个最大值点 for (Dist=0; Dist<MaxDist;Dist++) { for(AngleNumber=0; AngleNumber<MaxAngleNumber; AngleNumber++) { if((int)*(pNewData+Dist*MaxAngleNumber+AngleNumber)>MaxValue2.Value) { MaxValue2.Value = (int)*(pNewData+Dist*MaxAngleNumber+AngleNumber); MaxValue2.Dist = Dist; MaxValue2.AngleNumber = AngleNumber; } } } //判断两直线是否平行 if(abs(MaxValue1.AngleNumber-MaxValue2.AngleNumber)<=2) { //两直线平行，在缓存图像中重绘这两条直线 for(i = 0;i <Dimensions.cy ;i++) { for(j = 0;j <Dimensions.cx; j++) { //对256彩色图像进行处理 if(pB->m_lpBMIH->biBitCount ==8) { // 指向缓存图像倒数第j行，第i个象素的指针 pDest = pData + SaveSize.cx * i + j; pSrc = pB->m_lpImage + i*SaveSize.cx + j; //如果该点在某一条平行直线上，则在缓存图像上将该点赋为黑 //在第一条直线上 Dist = (int) fabs(j*cos(MaxValue1.AngleNumber*2*pi/180.0) + \ i*sin(MaxValue1.AngleNumber*2*pi/180.0)); if ((Dist == MaxValue1.Dist) && (*pSrc==0)) *pDest = (unsigned char)50; //在第二条直线上 Dist = (int) fabs(j*cos(MaxValue2.AngleNumber*2*pi/180.0) + \ i*sin(MaxValue2.AngleNumber*2*pi/180.0)); if ((Dist == MaxValue2.Dist) && (*pSrc==0)) *pDest = (unsigned char)50; } //对24位真彩色图像进行处理 else { pDest = pData + SaveSize.cx * i + 3*j; pSrc = pB->m_lpImage + i*SaveSize.cx +3*j; //如果该点在某一条平行直线上，则在缓存图像上将该点赋为黑 //在第一条直线上 Dist = (int) fabs(j*cos(MaxValue1.AngleNumber*2*pi/180.0) + \ i*sin(MaxValue1.AngleNumber*2*pi/180.0)); if (Dist == MaxValue1.Dist&& (*pSrc==0)) { *pDest = (unsigned char)0; *(pDest +1) = (unsigned char)0; *(pDest +2) = (unsigned char)255; } //在第二条直线上 Dist = (int) fabs(j*cos(MaxValue2.AngleNumber*2*pi/180.0) + \ i*sin(MaxValue2.AngleNumber*2*pi/180.0)); if (Dist == MaxValue2.Dist && (*pSrc==0)) { *pDest = (unsigned char)0; *(pDest +1) = (unsigned char)0; *(pDest +2) = (unsigned char)255; } } } } } memcpy ( pB->m_lpImage,pData,SaveSize.cx * SaveSize.cy); }