Lazarus Pascal Requires Chilkat v11.7.0+

Deflate Compression Level When Optimizing a PDF

See more PDF Optimization Examples

Demonstrates compressionLevel, which is the deflate level (1 to 9, 9 by default) used for every stream the optimizer re-encodes. Level 9 is the smallest and the slowest; level 1 is the quickest. The difference is usually a percent or two, so level 9 is the right default for a file that will be downloaded many times, and a lower level is worth considering only when a server optimizes PDFs on the fly. A value outside 1 to 9 is an error. Lazarus Pascal

program ChilkatDemo;

// Demonstrates using the Chilkat Pascal wrapper via the C bridge DLL.
// Builds as a console application under Lazarus (FPC) or Delphi.

{$IFDEF FPC}
  {$MODE DELPHI}
{$ENDIF}
{$APPTYPE CONSOLE}

uses
  {$IFDEF UNIX}
  cthreads,
  {$ENDIF}
  SysUtils,
  CkDllLoader,
  Chilkat.FileAccess,
  Chilkat.Pdf,
  Chilkat.JsonObject;

// ---------------------------------------------------------------------------

procedure RunDemo;
var
  success: Boolean;
  fac: TFileAccess;
  json: TJsonObject;
  jsonOut: TJsonObject;
  pdf1: TPdf;
  pdf9: TPdf;
  pdfBad: TPdf;

begin
  success := False;

  //  This example requires the Chilkat API to have been previously unlocked.
  //  See Global Unlock Sample for sample code.

  //  The PDF used in this example is available at watersense_accomplishments.pdf

  fac := TFileAccess.Create;
  json := TJsonObject.Create;
  jsonOut := TJsonObject.Create;

  pdf1 := TPdf.Create;
  success := pdf1.LoadFile('qa_data/pdf/watersense_accomplishments.pdf');
  if (success = False) then
    begin
      WriteLn(pdf1.LastErrorText);
      Exit;
    end;
  json.UpdateInt('compressionLevel',1);
  success := pdf1.Optimize('optimize',json,jsonOut);
  if (success = False) then
    begin
      WriteLn(pdf1.LastErrorText);
      Exit;
    end;
  success := pdf1.WriteFile('qa_output/watersense_level1.pdf');
  if (success = False) then
    begin
      WriteLn(pdf1.LastErrorText);
      Exit;
    end;
  WriteLn('level 1: ' + fac.FileSize('qa_output/watersense_level1.pdf'));

  pdf9 := TPdf.Create;
  success := pdf9.LoadFile('qa_data/pdf/watersense_accomplishments.pdf');
  if (success = False) then
    begin
      WriteLn(pdf9.LastErrorText);
      Exit;
    end;
  json.UpdateInt('compressionLevel',9);
  success := pdf9.Optimize('optimize',json,jsonOut);
  if (success = False) then
    begin
      WriteLn(pdf9.LastErrorText);
      Exit;
    end;
  success := pdf9.WriteFile('qa_output/watersense_level9.pdf');
  if (success = False) then
    begin
      WriteLn(pdf9.LastErrorText);
      Exit;
    end;
  WriteLn('level 9: ' + fac.FileSize('qa_output/watersense_level9.pdf'));

  //  A level outside 1..9 fails, and LastErrorText says why.
  pdfBad := TPdf.Create;
  success := pdfBad.LoadFile('qa_data/pdf/watersense_accomplishments.pdf');
  if (success = False) then
    begin
      WriteLn(pdfBad.LastErrorText);
      Exit;
    end;
  json.UpdateInt('compressionLevel',12);
  success := pdfBad.Optimize('optimize',json,jsonOut);
  if (success = False) then
    begin
      WriteLn('compressionLevel 12 was refused, as it should be.');
    end;


  fac.Free;
  json.Free;
  jsonOut.Free;
  pdf1.Free;
  pdf9.Free;
  pdfBad.Free;

end;

// ---------------------------------------------------------------------------

begin

  try
    RunDemo;
  except
    on E: Exception do
      WriteLn('Unhandled exception: ', E.ClassName, ': ', E.Message);
  end;

  WriteLn;
  {$IFDEF MSWINDOWS}
  WriteLn('Press Enter to exit...');
  ReadLn;
  {$ENDIF}
end.