C中运行matlab

[brufeng]

C中已经配置好了matlab，然后程序编译链接通过，但是运行时会出错，经过查找发现是mxSetData这句的问题，该程序就是将c中一个int型的数据赋值到了matlab中，后面把固定文件名的jpg格式图片转换成灰度图片，但是不知道怎么才能解决，请高手指点~~

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
/*matlab调用部分*/
#include <engine.h>
#include <matrix.h>
#include <mat.h>
#pragma comment(lib,"libeng.lib")
#pragma comment(lib,"libmx.lib")
#pragma comment(lib,"libmat.lib")
void main()
{	
	Engine *ep = engOpen (NULL); //启用matlab引擎
	engSetVisible(ep,0);//关闭matlab调用窗口
	engEvalString(ep,"cd work");//调整工作空间到work
	int i=0;
	mxArray *pi=mxCreateNumericMatrix(1,1,mxINT32_CLASS,mxREAL);
	mxSetData(pi,&i);
	printf("run here!");
    /*调用matlab处理彩色图像为灰度图像，保存灰度图像并保存为二维数组*/
	int times=100; //处理图片帧数

	engEvalString(ep,"name='动态图像分析'");
	for(i=0;i<times;i++)
	{
		if(i<10)
		{
			engPutVariable(ep,"i",pi);
			engEvalString(ep,"baseName=strcat(name,'000',num2str(i));");
		}
		else if(i<100)
		{
			engPutVariable(ep,"i",pi);
			engEvalString(ep,"baseName=strcat(name,'00',num2str(i));");
		}
		else if(i<1000)
		{
			engPutVariable(ep,"i",pi);
			engEvalString(ep,"baseName=strcat(name,'0',num2str(i));");
		}
		else
		{
			engPutVariable(ep,"i",pi);
			engEvalString(ep,"baseName=strcat(name,num2str(i));");
		}
		engEvalString(ep,"imageName=strcat(baseName,'.jpg');");
                engEvalString(ep,"I= imread(imageName);");
		engEvalString(ep,"J=rgb2gray(I);");
		engEvalString(ep,"fname=strcat(baseName,'.bmp');");
		engEvalString(ep,"imwrite(J,fname);");
	}
	engClose(ep);//释放matlab引擎
}

下面是调试运行到mxArray和mxSetData这两步的情况：
i 0
mxINT32_CLASS 12
mxREAL 0
pi 0xcccccccc
---------------------------------
- &i 0x0012ff40
0
mxINT32_CLASS 12
mxREAL 0
pi 0x017a4b18
---------------------------------
可以看到pi指向的地址和&i的地址并不相同，这个正常吗？在下新手，求高手指点。