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Perl Requires Chilkat v11.7.0+

A PDF Watermark That Only Appears When Printed

See more PDF Watermark Examples

Demonstrates a watermark that is invisible on screen and appears on paper, which is what a "printed copies are uncontrolled" marking needs. Two approaches can do it: an optional-content layer with layer.view off and layer.print on, which also gives the reader an entry in the layers panel of the viewer (layer.locked stops them switching it), and a Watermark annotation with annotation.view false and annotation.print true. annotation.fixedPrint keeps the printed size and position the same whatever paper it goes on.

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Perl
use chilkat();

$success = 0;

#  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 two_page_memo.pdf

$pdf = chilkat::CkPdf->new();
$success = $pdf->LoadFile("qa_data/pdf/two_page_memo.pdf");
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

$json = chilkat::CkJsonObject->new();
$json->UpdateString("type","text");
$json->UpdateString("text","UNCONTROLLED WHEN PRINTED");
$json->UpdateString("id","printonly");

#  As a layer: off on screen, on when printing, and locked so the reader cannot switch it on.
$json->UpdateString("approach","layer");
$json->UpdateString("layer.name","Print marking");
$json->UpdateString("layer.view","off");
$json->UpdateString("layer.print","on");
$json->UpdateBool("layer.locked",1);

$json->UpdateString("rotation","diagonal");
$json->UpdateString("scale.fit","page");
$json->UpdateNumber("scale.fitPercent","70");
$json->UpdateNumber("opacity","0.3");

$jsonOut = chilkat::CkJsonObject->new();
$success = $pdf->Watermark("add",$json,$jsonOut);
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

print "layer id: " . $jsonOut->stringOf("id") . " pages: " . $jsonOut->stringOf("pages") . "\r\n";

$success = $pdf->WriteFile("qa_output/memo_print_only.pdf");
if ($success == 0) {
    print $pdf->lastErrorText() . "\r\n";
    exit;
}

#  The same thing as an annotation instead.
$pdf2 = chilkat::CkPdf->new();
$success = $pdf2->LoadFile("qa_data/pdf/two_page_memo.pdf");
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

$json2 = chilkat::CkJsonObject->new();
$json2->UpdateString("type","text");
$json2->UpdateString("text","UNCONTROLLED WHEN PRINTED");
$json2->UpdateString("id","printonly2");
$json2->UpdateString("approach","annotation");
$json2->UpdateBool("annotation.view",0);
$json2->UpdateBool("annotation.print",1);
$json2->UpdateBool("annotation.fixedPrint",1);
$json2->UpdateString("rotation","diagonal");
$success = $pdf2->Watermark("add",$json2,$jsonOut);
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

print "annotation id: " . $jsonOut->stringOf("id") . "\r\n";

#  Sample output:

#  layer id: printonly pages: 1-2
#  annotation id: printonly2