CImage转Mat

void CSizedetectionDlg::CImageToMat(ATL::CImage& cimage, Mat& mat)
{
if (true == cimage.IsNull())
{
return;
}

int nChannels = cimage.GetBPP() / 8;
if ((1 != nChannels) && (3 != nChannels))
{
    return;
}
int nWidth    = cimage.GetWidth();
int nHeight   = cimage.GetHeight();


//重建mat
if (1 == nChannels)
{
    mat.create(nHeight, nWidth, CV_8UC1);
}
else if(3 == nChannels)
{
    mat.create(nHeight, nWidth, CV_8UC3);
}


//拷贝数据


uchar* pucRow;                                    //指向数据区的行指针
uchar* pucImage = (uchar*)cimage.GetBits();        //指向数据区的指针
int nStep = cimage.GetPitch();                    //每行的字节数,注意这个返回值有正有负


for (int nRow = 0; nRow < nHeight; nRow++)
{
    pucRow = (mat.ptr<uchar>(nRow));
    for (int nCol = 0; nCol < nWidth; nCol++)
    {
        if (1 == nChannels)
        {
            pucRow[nCol] = *(pucImage + nRow * nStep + nCol);
        }
        else if (3 == nChannels)
        {
            for (int nCha = 0 ; nCha < 3; nCha++)
            {
                pucRow[nCol * 3 + nCha] = *(pucImage + nRow * nStep + nCol * 3 + nCha);
            }            
        }
    }    
}

}
(有木有大哥大知道该怎么用啊，写好也后，直接调用它CImageToMat(参数，参数)这样不能用啊，该如何使用。CImage做打开图片Mat用于运算图片，做图像运算的时候还是不能读到mat里面)我直接就这样调用不行CImageToMat(g_image, g_srcImage);CImage g_image,Mat g_srcImage;她两是全局的

static void CSizedetectionDlg::CImageToMat(ATL::CImage& cimage, Mat& mat)
{
//...
}
调用
CSizedetectionDlg::CImageToMat(g_image, g_srcImage);