sgcPDF，面向 Delphi 与 C++ Builder 的纯 Pascal PDF 库

procedure StampExistingPDF(const AInput, AOutput: string);
var
  oEditor: TsgcPDFEditor;
  oWatermark: TsgcPDFWatermarkOptions;
begin
  oEditor := TsgcPDFEditor.Create;
  try
    oEditor.LoadFromFile(AInput);
    oWatermark.Text := 'CONFIDENTIAL';
    oWatermark.Font := sfHelveticaBold;
    oWatermark.FontSize := 48;
    oWatermark.Rotation := 45;
    oWatermark.Opacity := 0.3;
    oWatermark.R := 0.5;
    oWatermark.G := 0.5;
    oWatermark.B := 0.5;
    oEditor.AddWatermarkAllPages(oWatermark);
    oEditor.AddPageNumbers(sfHelvetica, 10, 'Page %d of %d');
    oEditor.SaveToFile(AOutput);
  finally
    oEditor.Free;
  end;
end;

procedure PrintAllText(const AFileName: string);
var
  oPDF: TsgcPDFDocument;
  i: Integer;
begin
  oPDF := TsgcPDFDocument.Create;
  try
    oPDF.LoadFromFile(AFileName);
    for i := 0 to oPDF.PageCount - 1 do
      WriteLn(string(oPDF.ExtractTextW(i)));
  finally
    oPDF.Free;
  end;
end;

procedure RenderPageToPNG(const APDFFile, APNGFile: string; ADPI: Integer);
var
  oPDF: TsgcPDFDocument;
  oRenderer: TsgcPDFRendererRaster;
  oPage: TsgcPDFPage;
begin
  oPDF := TsgcPDFDocument.Create;
  try
    oPDF.LoadFromFile(APDFFile);
    oPage := oPDF.Pages[0];
    // pure Pascal rasterizer: no GDI, runs on Windows and Linux servers
    oRenderer := TsgcPDFRendererRaster.Create;
    try
      oRenderer.RenderPageToPNG(oPDF.Parser, oPage.PageDict,
        Round(oPage.Width * ADPI / 72), Round(oPage.Height * ADPI / 72),
        APNGFile);
    finally
      oRenderer.Free;
    end;
  finally
    oPDF.Free;
  end;
end;