以前在做图像处理的时候用到了图像的旋转，opencv自带的flip函数只能180度，因为需要旋转任意角度，顺时针和逆时针的情况，所以去找了些效果比较好的函数来实现。网上有的旋转函数有内存泄露的现象，现在把修改过我用过的无内存泄露的函数分享一下：

一：

void  cvRotate(IplImage* src,int angle)
 
{ 
 
IplImage * dst = 0;
 
 
 
dst = cvCloneImage (src);
 
double delte = 1.0;
 
double factor = 1.0;
 
float m[6];
 

 
CvMat M = cvMat( 2, 3, CV_32F, m );
 
int w = src->width;
 
int h = src->height;
 
 
 
m[0] = (float)(factor*cos(-angle*2*CV_PI/180.));
 
m[1] = (float)(factor*sin(-angle*2*CV_PI/180.));
 
m[2] = w*0.5f;
 
m[3] = -m[1];
 
m[4] = m[0];
 
m[5] = h*0.5f;
 
cvZero (dst);
 
cvGetQuadrangleSubPix( src, dst, &M);
*src = http://www.mamicode.com/*dst;>

二：
IplImage*  cvRotate2(IplImage* src,IplImage * dst )
{
	
	double delte = 1.0;
 
	double factor =1.0;


   float m[6];
 

int angle =90;



int tempLength = (int)sqrt(float(src->width * src->width + src->height * src->height)) + 10;  
int tempX = (tempLength + 1) / 2 - src->width / 2;    
int tempY = (tempLength + 1) / 2 - src->height / 2;    
    

IplImage* temp = cvCreateImage(cvSize(src->width,src->height), src->depth, src->nChannels);   
cvZero(temp);    

cvCopy(src, temp, NULL);   



int w = temp->width;   
int h = temp->height;  
 
m[0] = (float) cos( angle * CV_PI / 180.);   
m[1] = (float) sin( angle * CV_PI / 180.);   
 
m[2] = w*0.5f;
 
m[3] = -m[1];
 
m[4] = m[0];
 
m[5] = h*0.5f;
 

 CvMat M = cvMat(2, 3, CV_32F, m);  
cvGetQuadrangleSubPix( temp,dst, &M);


 cvReleaseImage(&temp);
return dst;

}


三：
IplImage *cvRotate(IplImage *imgSrc)
{  
    double degree = 270; // rotate 30 degree  
    double angle = degree  * CV_PI / 180.; // angle in radian  
    double a = sin(angle), b = cos(angle); // sine and cosine of angle  
  
    
    int w_src = http://www.mamicode.com/imgSrc->width;  >

四：
cvTranspose( const CvArr* src, CvArr* dst );的使用
五：推荐
void  cvRotate(IplImage* img,IplImage *img_rotate,int degree)
{
	
 //旋转中心为图像中心  
    CvPoint2D32f center;    
    center.x=float (img->width/2.0+0.5);  
    center.y=float (img->height/2.0+0.5);  
    //计算二维旋转的仿射变换矩阵  
    float m[6];              
    CvMat M = cvMat( 2, 3, CV_32F, m );  
    cv2DRotationMatrix( center, degree,1, &M);  
    //变换图像，并用黑色填充其余值  
    cvWarpAffine(img,img_rotate, &M,CV_INTER_LINEAR+CV_WARP_FILL_OUTLIERS,cvScalarAll(0) );  
}


OpenCV基础篇——图形图像旋转