Xojo Plugin 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. Xojo Plugin

Dim success As Boolean
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

Dim pdf As New Chilkat.Pdf
success = pdf.LoadFile("qa_data/pdf/four_pages.pdf")
If (success = False) Then
    System.DebugLog(pdf.LastErrorText)
    Return
End If

Dim json As New Chilkat.JsonObject
success = json.UpdateString("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");
success = json.UpdateString("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.
success = json.UpdateString("units","in")
success = json.UpdateNumber("image.width","1.5")

//  Bottom-right, half an inch in from the page edges.
success = json.UpdateString("position.align","bottomRight")
success = json.UpdateNumber("position.margin","0.5")
success = json.UpdateNumber("opacity","0.85")
success = json.UpdateString("id","logo")

Dim jsonOut As New Chilkat.JsonObject
success = pdf.Watermark("add",json,jsonOut)
If (success = False) Then
    System.DebugLog(pdf.LastErrorText)
    Return
End If

System.DebugLog("id: " + jsonOut.StringOf("id") + " pages: " + jsonOut.StringOf("pages"))

success = pdf.WriteFile("qa_output/four_pages_logo.pdf")
If (success = False) Then
    System.DebugLog(pdf.LastErrorText)
    Return
End If

//  Sample output:

//  id: logo pages: 1-4