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Perl Requires Chilkat v11.7.0+

Tile a Watermark Across a PDF Page

See more PDF Watermark Examples

Demonstrates a tiled watermark, which repeats the stamp over the whole page instead of placing it once. Tiling overrides position.align; tile.spacingX and spacingY set the gaps, and tile.stagger offsets alternate rows by half a tile so the pattern does not line up in columns. A faint tiled stamp carrying the name or address is the usual way to mark a document so that a leaked copy can be traced back, and zOrder back keeps it behind the text where it does not hinder reading.

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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 long_report.pdf

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

$json = chilkat::CkJsonObject->new();
$json->UpdateString("type","text");

#  {date:FORMAT} is replaced per page when the watermark is added.  The other placeholders are
#  {page}, {pages} and {filename}; {{ gives a literal brace.
$json->UpdateString("text",'jdoe@example.com  {date:yyyy-MM-dd}');
$json->UpdateString("id","trace");
$json->UpdateString("zOrder","back");
$json->UpdateNumber("font.size","14");
$json->UpdateNumber("opacity","0.15");
$json->UpdateNumber("rotation","30");

$json->UpdateBool("tile.enabled",1);
$json->UpdateNumber("tile.spacingX","60");
$json->UpdateNumber("tile.spacingY","80");
$json->UpdateBool("tile.stagger",1);

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

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

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

#  Sample output:

#  id: trace pages: 1-3