VC中使用GDI+在内存转换图片类型

VC中使用GDI+在内存转换图片类型

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　　详细代码如下：

BOOL MBmpToMImage(CMemFile& cbfBmp, CMemFile& cbfImage, CString strType)
{
　int iBmpSize = cbfBmp.GetLength();
　HGLOBAL hMemBmp = GlobalAlloc(GMEM_FIXED, iBmpSize);
　if (hMemBmp == NULL) return FALSE;
　IStream* pStmBmp = NULL;
　CreateStreamOnHGlobal(hMemBmp, FALSE, &pStmBmp);
　if (pStmBmp == NULL)
　{
　　GlobalFree(hMemBmp);
　　return FALSE;
　}
　BYTE* pbyBmp = (BYTE *)GlobalLock(hMemBmp);
　cbfBmp.SeekToBegin();
　cbfBmp.Read(pbyBmp, iBmpSize);

　Image* imImage = NULL;
　imImage = Image::FromStream(pStmBmp, FALSE);
　if (imImage == NULL)
　{
　　GlobalUnlock(hMemBmp);
　　GlobalFree(hMemBmp);
　　return FALSE;
　}
　USES_CONVERSION;
　CLSID clImageClsid;
　GetImageCLSID(A2W("image/"+strType.GetBuffer(0)), &clImageClsid);

　HGLOBAL hMemImage = GlobalAlloc(GMEM_MOVEABLE, 0);
　if (hMemImage == NULL)
　{
　　pStmBmp-Release();
　　GlobalUnlock(hMemBmp);
　　GlobalFree(hMemBmp);
　　if (imImage != NULL) delete imImage;
　　return FALSE;
　}　
　IStream* pStmImage = NULL;
　CreateStreamOnHGlobal(hMemImage, TRUE, &pStmImage);
　if (pStmImage == NULL)
　{
　　pStmBmp-Release();
　　GlobalUnlock(hMemBmp);
　　GlobalFree(hMemBmp);
　　GlobalFree(hMemImage);
　　if (imImage != NULL) delete imImage
　　　return FALSE;
　}
　imImage-Save(pStmImage, &clJpgClsid);
　if (pStmImage == NULL)
　{
　　pStmBmp-Release();
　　pStmImageRelease();
　　GlobalUnlock(hMemBmp);
　　GlobalFree(hMemBmp);
　　GlobalFree(hMemImage;
　　if (imImage != NULL) delete imImage;
　　return FALSE;
　}
　LARGE_INTEGER liBegin = {0};
　pStmImage-Seek(liBegin, STREAM_SEEK_SET, NULL);
　BYTE* pbyImage = (BYTE *)GlobalLock(hMemImage);
　cbfImage.SeekToBegin();
　cbfImage.Write(pbyImage, GlobalSize(hMemImage));

　if (imImage != NULL) delete imImage;
　pStmBmp-Release();
　pStmImage-Release();
　GlobalUnlock(hMemBmp);
　GlobalUnlock(hMemImage);
　GlobalFree(hMemBmp);
　GlobalFree(hMemImage);
　return TRUE;
}