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PowerShell 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.

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PowerShell
Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$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 = New-Object Chilkat.Pdf
$success = $pdf.LoadFile("qa_data/pdf/four_pages.pdf")
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$json = New-Object Chilkat.JsonObject
$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");
$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.
$json.UpdateString("units","in")
$json.UpdateNumber("image.width","1.5")

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

$jsonOut = New-Object Chilkat.JsonObject
$success = $pdf.Watermark("add",$json,$jsonOut)
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$("id: " + $jsonOut.StringOf("id") + " pages: " + $jsonOut.StringOf("pages"))

$success = $pdf.WriteFile("qa_output/four_pages_logo.pdf")
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

#  Sample output:

#  id: logo pages: 1-4