Save PDF as a bitmap in C++ Builder

void __fastcall TfrmMain::SaveAsBitmap()
{
 Graphics::TBitmap *bit = new Graphics::TBitmap;
 int w, h, resx = 100, resy = 100, pageno;
 HDC DC;
 TJPEGImage* jpeg;


 pageno = WPViewPDF->Page;


 w = WPViewPDF->CommandEx(COMPDF_GetPageWidth, 1);
 h = WPViewPDF->CommandEx(COMPDF_GetPageHeight, 1);


 WPViewPDF->CommandEx(COMPDF_PrintHDCSetXRes, resx);
 WPViewPDF->CommandEx(COMPDF_PrintHDCSetYRes, resy);
 WPViewPDF->CommandEx(160, pageno); // Select Page number


 bit->Width = MulDiv(w, resx, 72);
 bit->Height = MulDiv(h, resy, 72);
 DC = bit->Canvas->Handle;


 Rectangle(DC, 0, 0, bit->Width - 1, bit->Height - 1);
 WPViewPDF->CommandEx(161, Integer(DC));


 jpeg = new TJPEGImage;


 jpeg->Assign(bit);
 bit->SaveToFile("C:\\test.bmp");
 jpeg->SaveToFile("C:\\test.jpg");


 jpeg->Free();
 bit->Free();
}