opencv-Win32下HBITMAP格式图像 Convert to为opencv下 IplImage

// hbitmap convert to IplImage
IplImage* hBitmapToIpl(HBITMAP hBmp)
{
    BITMAP bmp;
    GetObject(hBmp,sizeof(BITMAP),&bmp);

    // get channels which equal 1 2 3 or 4
    // bmBitsPixel :
    // Specifies the number of bits
    // required to indicate the color of a pixel.
    int nChannels = bmp.bmBitsPixel == 1 ? 1 : bmp.bmBitsPixel/8 ;

    // get depth color bitmap or grayscale
    int depth = bmp.bmBitsPixel == 1 ? IPL_DEPTH_1U : IPL_DEPTH_8U;


    // create header image
    IplImage* img = cvCreateImage(cvSize(bmp.bmWidth,bmp.bmHeight),depth,nChannels);

    // allocat memory for the pBuffer
    BYTE *pBuffer = new BYTE[bmp.bmHeight*bmp.bmWidth*nChannels];

    // copies the bitmap bits of a specified device-dependent bitmap into a buffer
    GetBitmapBits(hBmp,bmp.bmHeight*bmp.bmWidth*nChannels,pBuffer);

    // copy data to the imagedata
    memcpy(img->imageData,pBuffer,bmp.bmHeight*bmp.bmWidth*nChannels);
    delete pBuffer;

    // create the image
    IplImage *dst = cvCreateImage(cvGetSize(img),img->depth,3);
    // convert color
    cvCvtColor(img,dst,CV_BGRA2BGR);
    cvReleaseImage(&img);
    return dst;
}