整体拷贝bmp 图片buffer

Gdiplus::BitmapData bmpData;
Gdiplus::Rect rect(0, 0, g_pBitmap->GetWidth(), g_pBitmap->GetHeight());

g_pBitmap->LockBits(
		rect,
		Gdiplus::ImageLockModeWrite,
		PixelFormat32bppARGB,
		&bmpData);

// Write to the temporary buffer provided by LockBits.  
UINT* pixels = (UINT*)bmpData.Scan0;
int byteCount = bmpData.Stride * bmpData.Height;
memcpy(g_pixcelMemory, pixels, byteCount);

g_pBitmap->UnlockBits(&bmpData);