【OpenCV学习】子区域处理

#pragma comment( lib, "cxcore.lib" ) 
#pragma comment( lib, "cv.lib" ) 
#pragma comment( lib, "highgui.lib" ) 
#include <cv.h> 
#include <highgui.h> 
#include <stdio.h> 
int main(int argc, char** argv) 
{ 
 
    IplImage *src,*sub_img; 
    cvNamedWindow("Example3_13_pre", CV_WINDOW_AUTOSIZE); 
    cvNamedWindow("Example3_13_post", CV_WINDOW_AUTOSIZE);   
    src = cvLoadImage("dog.jpg"); 
    int x = 150; 
    int y = 300; 
    int width = 200; 
    int height = 200; 
    int add = 150; 
    //子窗口的初始化 
    sub_img =  cvCreateImageHeader(cvSize(width, height),src->depth,src->nChannels); 
    sub_img->origin = src->origin;      
    //子窗口的widthStep和主窗口的widthStep相等 
    sub_img->widthStep = src->widthStep; 
    //注意这个公式,子窗口的图像数据指针首地址指向了主窗口中由子窗口左上角坐标x,y指定的相应位置 
    sub_img->imageData = src->imageData + y * src->widthStep  + x * src->nChannels; 
    cvShowImage( "Example3_13_pre", src);     
    cvAddS(sub_img, cvScalar(add),sub_img); 
    cvShowImage( "Example3_13_post",src); 
    cvWaitKey(); 
    cvReleaseImage( &src ); 
    //释放子窗口的头部资源 
    cvReleaseImageHeader(&sub_img); 
    cvDestroyWindow("Example3_13_pre"); 
    cvDestroyWindow("Example3_13_post");    
    return 0; 
}