根据角度进行旋转

<!-- lang: cpp -->
//根据角度进行旋转，角度为水平正方向,angle为弧度

void ImageRotate(const IplImage src,IplImage dst,

            double angle,CvScalar fillVal,int hor)

{

double scale = 1.0;
double a = 0.0; 
CvMat* rot_mat = cvCreateMat(2,3,CV_32FC1);

CvPoint2D32f center = cvPoint2D32f(
    0,
    0
    );

if(hor)
{
    a= -(angle)*180/CV_PI;
    cv2DRotationMatrix(center,a,scale,rot_mat);
}
else
{
    cvSet2D(rot_mat,0,0,cvScalar(1));
    cvSet2D(rot_mat,0,1,cvScalar(0));
    cvSet2D(rot_mat,0,2,cvScalar(0));
    cvSet2D(rot_mat,1,0,cvScalar(-1/tan(angle)));
    cvSet2D(rot_mat,1,1,cvScalar(1));
    cvSet2D(rot_mat,1,2,cvScalar(0));
}
/*cvSet2D(rot_mat,0,0,cvScalar(1/cos(angle)));
cvSet2D(rot_mat,0,1,cvScalar(-tan(angle)));
cvSet2D(rot_mat,0,2,cvScalar(0));
cvSet2D(rot_mat,0,2,cvScalar(1));
cvSet2D(rot_mat,0,2,cvScalar(0));*/

cvWarpAffine(src,dst,rot_mat,CV_WARP_FILL_OUTLIERS,fillVal);


//对超出的边界的部分用原图中的像素点进行填充
/*for(int i=0;i<src->height;i++)
{
    uchar* ptr = (uchar*)(dst->imageData+i*dst->widthStep);
    uchar* ptr1 = (uchar*)(src->imageData+i*src->widthStep);
    for(int j=0;j<src->width;j++)
    {
        if(ptr[j*3] == 0 && ptr[j*3+1] == 0 && ptr[j*3+2] == 0)
        {
            ptr[j*3] = ptr1[j*3];
            ptr[j*3+1] = ptr1[j*3+1];
            ptr[j*3+2] = ptr1[j*3+2];
        }
    }
}*/

cvReleaseMat(&rot_mat);

}