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PHP Extension Requires Chilkat v11.7.0+

Add a CONFIDENTIAL Watermark to Every Page of a PDF

See more PDF Watermark Examples

Demonstrates the simplest watermark: a line of text across every page. "rotation" set to diagonal runs the text from the bottom-left corner to the top-right, computed for each page size, and "scale" with fit page sizes it to fill 80 percent of the page. The watermark is stored as a marked artifact by default, which means viewers show it, text extraction leaves it out, and it can be found and removed again later. Nothing is written until WriteFile is called.

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PHP Extension
<?php

include("chilkat.php");

$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 long_report.pdf

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

$json = new CkJsonObject();
$json->UpdateString('type','text');
$json->UpdateString('text','CONFIDENTIAL');

//  An id of your own choosing, so that the watermark can be found and removed later.  One is
//  generated when you do not give one.
$json->UpdateString('id','confidential');

$json->UpdateString('color','#C00000');
$json->UpdateNumber('opacity','0.25');
$json->UpdateString('rotation','diagonal');
$json->UpdateString('scale.fit','page');
$json->UpdateNumber('scale.fitPercent','80');

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

//  The id, and the pages it was stamped on.  "pages" defaults to all.
print 'id: ' . $jsonOut->stringOf('id') . "\n";
print 'pages: ' . $jsonOut->stringOf('pages') . "\n";

$success = $pdf->WriteFile('qa_output/report_confidential.pdf');
if ($success == false) {
    print $pdf->lastErrorText() . "\n";
    exit;
}

//  Sample output:

//  id: confidential
//  pages: 1-3

?>