PDFtoolkit VCL
Edit, enhance, secure, merge, split, view, print PDF and AcroForms documents

Compatibility

Delphi C++Builder

Home » Newsletter » October 2011

By V. Subhash

In an earlier article, we showed two ways of converting PDF to images. In both cases, you had to use an external GDI+ library. In Version 4 of PDFtoolkit, one of the GDI libraries is now used internally and export to image formats has been simplified.

In Version 4, a new method TgtPDFDocument.SaveAsImage() has been introduced. You specify the format using the TgtImageType argument and the image settings in the TgtImageProperties argument.

public procedure SaveAsImage(
    aPageRange: String;
    aImagetype: TgtImageType = itBitmap;
    aLocation: String = '';
    aFileNamePrefix: String = '';
    aImageProperties: TgtImageProperties = nil
);

public TgtImageType = (
  itBitmap,
  itJPEG,
  itEMF,
  itSinglePageTIFF,
  itMultiPageTIFF
);

If you have installed Version 4, just create a new VCL forms application project, drop a button, use this code example. You will see how easy it is to export PDF pages to images.

unit Export_PDF_To_Images;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtDlgs,
  gtPDFDoc, gtExPDFDoc, gtCstPDFDoc, gtPDFUtils, gtExProPDFDoc;

type
  TForm3 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form3: TForm3;

implementation

{$R *.dfm}

procedure TForm3.Button1Click(Sender: TObject);
var
  gtPDFDocument1: TgtPDFDocument;
  OpenTextFileDialog1: TOpenTextFileDialog;
  I, N: Integer;
begin
  OpenTextFileDialog1 := TOpenTextFileDialog.Create(nil);
  gtPDFDocument1 := TgtPDFDocument.Create(nil);

  OpenTextFileDialog1.Filter := 'PDF documents (*.pdf)|*.pdf';;
  if OpenTextFileDialog1.Execute then begin
    try
      // Unload any previously loaded file
      if gtPDFDocument1.IsLoaded then begin
        gtPDFDocument1.Reset;
      end;

      // Make the user select a PDF document and load it
      gtPDFDocument1.LoadFromFile(OpenTextFileDialog1.FileName);
      // Export first two pages as JPEG images
      gtPDFDocument1.SaveAsImage('1,2', itJPEG);
      // Export first two pages as TIFF images
      gtPDFDocument1.SaveAsImage('1,2', itSinglePageTIFF);
      // Export first two pages as a single multi-page TIFF image
      gtPDFDocument1.SaveAsImage('1,2', itMultiPageTIFF);

      // Free IO resources
      gtPDFDocument1.Reset;
    except on Err:Exception
      do begin
        gtPDFDocument1.Reset;
        ShowMessage('Sorry, an exception was raised. ' + Err.Classname + ':' + Err.Message);
      end;
    end;
  end;
end;

end.

Downloads

Gnostice DevTools Team member Ramnish has created an application for demonstrating how PDF-to-image export works.

• PDF-To-Image Export EXE Demo