gdiplus将一种图片格式转换成另外一个指定图片格式，且可设置图片大小

int  TransPicture(LPCWSTR   lpSrcFile,LPCWSTR  lpDstExt, long nWidth, long nHeight, CStringW &strDstFile)           {   USES_CONVERSION;CFileFind   find;  #ifdef UNICODEif (!find.FindFile(lpSrcFile))//文件不存在 #elseif (!find.FindFile(W2A(lpSrcFile)))//文件不存在  #endif{find.Close();return 0;}find.Close();Image     *psrcImg=NULL;   psrcImg = Image::FromFile(lpSrcFile);if (!psrcImg || psrcImg->GetLastStatus() != Ok){return 0;}int   srcWidth=psrcImg->GetWidth();   int   srcHeight=psrcImg->GetHeight();   //   Construct   a   Graphics   object   based   on   the   image.   //Graphics   imgGraphics(psrcImg);   int nSaveWidth=nWidth;int nSaveHeight = nHeight;Bitmap   *pBitmap = ::new Bitmap(nSaveWidth,nSaveHeight);   Graphics   bmpGraphics(pBitmap);   //bmpGraphics.DrawImage(psrcImg,0,0,srcWidth,srcHeight);   bmpGraphics.DrawImage(psrcImg,RectF(0,0,nSaveWidth,nSaveHeight),0,0,srcWidth,srcHeight,UnitPixel);delete psrcImg;bmpGraphics.ReleaseHDC(NULL);//   Save   the   altered   image.LPWSTR   lpExt=PathFindExtensionW(lpSrcFile); LPWSTR   lpExtDst = NULL;lpDstExt++;LPWSTR   lpEncoder;  switch(*lpDstExt)   {   case   L'J':   case   L'j':   lpEncoder=L"image/jpeg";   lpExtDst = L".jpeg";  break;   case   L'P':   case   L'p':   lpEncoder=L"image/png";   lpExtDst = L".png"; break;   case   L'B':   case   L'b':   lpEncoder=L"image/bmp";  lpExtDst = L".bmp"; break;   case   L'G':   case   L'g':   lpEncoder=L"image/gif";   lpExtDst = L".gif"; break;   case   L't':   case   L'T':   lpEncoder=L"image/tiff";   lpExtDst = L".tiff"; break;   default:   lpEncoder=L"image/jpeg";   lpExtDst = L".jpeg"; }   CStringW strPicPath(lpSrcFile);CStringW strExt(lpExt);int nLen = strPicPath.Find(strExt);if(nLen>0)strPicPath=strPicPath.Left(nLen);strPicPath += lpExtDst;CLSID   imgClsid;   GetImageCLSID(lpEncoder,&imgClsid);Status statusSave = pBitmap->Save(strPicPath,&imgClsid,NULL); DeleteFileW(lpSrcFile);//lpSrcFile = strPicPath.GetBuffer();//strPicPath.ReleaseBuffer();strDstFile = CStringW(strPicPath);::delete pBitmap;return (statusSave == Ok )?1:0;}BOOL GetImageCLSID(const WCHAR* format, CLSID* pCLSID){UINT num = 0;UINT size = 0;ImageCodecInfo* pImageCodecInfo = NULL;GetImageEncodersSize(&num, &size);if(size == 0){return FALSE;}pImageCodecInfo = (ImageCodecInfo *)(malloc(size));if(pImageCodecInfo == NULL)return FALSE;GetImageEncoders(num, size, pImageCodecInfo); // Find for the support of format for image in the windowsfor(UINT i = 0; i < num; ++i){ //MimeType: Depiction for the program image  if( wcscmp(pImageCodecInfo[i].MimeType, format) == 0){  *pCLSID = pImageCodecInfo[i].Clsid; free(pImageCodecInfo); return TRUE;  }  }  free(pImageCodecInfo);  return FALSE; } 

gdiplus将一种图片格式转换成另外一个指定图片格式，且可设置图片大小