Delphi DLL Requires Chilkat v11.7.0+

Add an Image (Logo) Watermark to a PDF

See more PDF Watermark Examples

Demonstrates an image watermark placed in a corner of every page. The image is a PNG or JPEG given either by path ("image.path") or, as here, as base64 in the JSON itself ("image.base64"), which suits a server that keeps its logo in a database rather than on disk. PNG transparency is kept. Giving only a width keeps the aspect ratio, and the units member says those numbers are inches rather than points. Delphi DLL

var
success: Boolean;
pdf: HCkPdf;
json: HCkJsonObject;
jsonOut: HCkJsonObject;

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 four_pages.pdf

pdf := CkPdf_Create();
success := CkPdf_LoadFile(pdf,'qa_data/pdf/four_pages.pdf');
if (success = False) then
  begin
    Memo1.Lines.Add(CkPdf__lastErrorText(pdf));
    Exit;
  end;

json := CkJsonObject_Create();
CkJsonObject_UpdateString(json,'type','image');

//  A small PNG logo, base64 encoded.  Use "image.path" instead to name a PNG or JPEG file:
//     ignore = json.UpdateString("image.path","logo.png");
CkJsonObject_UpdateString(json,'image.base64','iVBORw0KGgoAAAANSUhEUgAAAGAAAAAgCAYAAADtwH1UAAAApElEQVR42u3a7QmAIBgAYTdpo/ZphhZti6IBylLrlXoO/G3cIeFHSgAAFDKM08rCy8Jzg6Ug8UJ0JF+EDuSXRGgxX8+jufxlTk0nFuCCiF360aidXICMiDP5uQgCXAxQI782ggAHEu7IP4sgQOcBIMA35ItgBQhQEqBmtbX6xl//hAUI3gcIELwTFiD4LEiA4NNQAYLvA+BGzJ0wvIrwLggA8DgbwPbrr8c7+lkAAAAASUVORK5CYII=');

//  The size to draw it at.  Give only the width and the height follows the aspect ratio.
CkJsonObject_UpdateString(json,'units','in');
CkJsonObject_UpdateNumber(json,'image.width','1.5');

//  Bottom-right, half an inch in from the page edges.
CkJsonObject_UpdateString(json,'position.align','bottomRight');
CkJsonObject_UpdateNumber(json,'position.margin','0.5');
CkJsonObject_UpdateNumber(json,'opacity','0.85');
CkJsonObject_UpdateString(json,'id','logo');

jsonOut := CkJsonObject_Create();
success := CkPdf_Watermark(pdf,'add',json,jsonOut);
if (success = False) then
  begin
    Memo1.Lines.Add(CkPdf__lastErrorText(pdf));
    Exit;
  end;
Memo1.Lines.Add('id: ' + CkJsonObject__stringOf(jsonOut,'id') + ' pages: ' + CkJsonObject__stringOf(jsonOut,'pages'));

success := CkPdf_WriteFile(pdf,'qa_output/four_pages_logo.pdf');
if (success = False) then
  begin
    Memo1.Lines.Add(CkPdf__lastErrorText(pdf));
    Exit;
  end;

//  Sample output:

//  id: logo pages: 1-4

CkPdf_Dispose(pdf);
CkJsonObject_Dispose(json);
CkJsonObject_Dispose(jsonOut);