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PHP Extension

Extract Metadata XML from PDF

See more PDF Signatures Examples

Demonstrates how to extract the metadata XML from a PDF.

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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.

$pdf = new CkPdf();

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

$sbXml = new CkStringBuilder();
// Note: Not all PDF files have metadata.  Metadata is optional.
$success = $pdf->GetMetadata($sbXml);
if ($success == false) {
    print $pdf->lastErrorText() . "\n";
    exit;
}

$xml = new CkXml();
$xml->LoadSb($sbXml,true);

print $xml->getXml() . "\n";

// Sample PDF metadata XML:
// (Code for parsing follows)

// Use this online tool to generate parsing code from sample XML: 
// Generate Parsing Code from XML

// <?xml version="1.0" encoding="utf-8"?>
// <x:xmpmeta xmlns:x="adobe:ns:meta/" x:xmptk="Adobe XMP Core 9.1-c001 79.675d0f7, 2023/06/11-19:21:16        ">
//     <rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
//         <rdf:Description rdf:about="" xmlns:xmp="http://ns.adobe.com/xap/1.0/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xmpMM="http://ns.adobe.com/xap/1.0/mm/" xmlns:pdf="http://ns.adobe.com/pdf/1.3/" xmlns:xmpRights="http://ns.adobe.com/xap/1.0/rights/">
//             <xmp:ModifyDate>2024-11-27T11:33:12-06:00</xmp:ModifyDate>
//             <xmp:CreateDate>2024-11-27T11:28:23-06:00</xmp:CreateDate>
//             <xmp:MetadataDate>2024-11-27T11:33:12-06:00</xmp:MetadataDate>
//             <xmp:CreatorTool>Adobe Acrobat Pro (32-bit) 24.3.20112</xmp:CreatorTool>
//             <dc:format>application/pdf</dc:format>
//             <dc:title>
//                 <rdf:Alt>
//                     <rdf:li xml:lang="x-default">Blank</rdf:li>
//                 </rdf:Alt>
//             </dc:title>
//             <dc:creator>
//                 <rdf:Bag>
//                     <rdf:li>Chilkat Software</rdf:li>
//                 </rdf:Bag>
//             </dc:creator>
//             <dc:description>
//                 <rdf:Alt>
//                     <rdf:li xml:lang="x-default">Blank Document</rdf:li>
//                 </rdf:Alt>
//             </dc:description>
//             <dc:subject>
//                 <rdf:Bag>
//                     <rdf:li>blank</rdf:li>
//                     <rdf:li>metadata</rdf:li>
//                     <rdf:li>document</rdf:li>
//                 </rdf:Bag>
//             </dc:subject>
//             <xmpMM:DocumentID>uuid:34535ffa-b632-43f1-b1fd-80cea6fdc351</xmpMM:DocumentID>
//             <xmpMM:InstanceID>uuid:69ace620-4c54-407f-8d45-6eebc90f34c2</xmpMM:InstanceID>
//             <pdf:Producer>Adobe Acrobat Pro (32-bit) 24.3.20112</pdf:Producer>
//             <pdf:Keywords>blank; metadata; document</pdf:Keywords>
//             <xmpRights:WebStatement>https://www.chilkatsoft.com/</xmpRights:WebStatement>
//         </rdf:Description>
//     </rdf:RDF>
// </x:xmpmeta>

$x_xmpmeta_xmlns_x = $xml->getAttrValue('xmlns:x');
$x_xmpmeta_x_xmptk = $xml->getAttrValue('x:xmptk');
$rdf_RDF_xmlns_rdf = $xml->chilkatPath('rdf:RDF|(xmlns:rdf)');
$rdf_Description_rdf_about = $xml->chilkatPath('rdf:RDF|rdf:Description|(rdf:about)');
$rdf_Description_xmlns_xmp = $xml->chilkatPath('rdf:RDF|rdf:Description|(xmlns:xmp)');
$rdf_Description_xmlns_dc = $xml->chilkatPath('rdf:RDF|rdf:Description|(xmlns:dc)');
$rdf_Description_xmlns_xmpMM = $xml->chilkatPath('rdf:RDF|rdf:Description|(xmlns:xmpMM)');
$rdf_Description_xmlns_pdf = $xml->chilkatPath('rdf:RDF|rdf:Description|(xmlns:pdf)');
$rdf_Description_xmlns_xmpRights = $xml->chilkatPath('rdf:RDF|rdf:Description|(xmlns:xmpRights)');
$xmp_ModifyDate = $xml->getChildContent('rdf:RDF|rdf:Description|xmp:ModifyDate');
$xmp_CreateDate = $xml->getChildContent('rdf:RDF|rdf:Description|xmp:CreateDate');
$xmp_MetadataDate = $xml->getChildContent('rdf:RDF|rdf:Description|xmp:MetadataDate');
$xmp_CreatorTool = $xml->getChildContent('rdf:RDF|rdf:Description|xmp:CreatorTool');
$dc_format = $xml->getChildContent('rdf:RDF|rdf:Description|dc:format');
$rdf_li_xml_lang = $xml->chilkatPath('rdf:RDF|rdf:Description|dc:title|rdf:Alt|rdf:li|(xml:lang)');
$rdf_li = $xml->getChildContent('rdf:RDF|rdf:Description|dc:title|rdf:Alt|rdf:li');
$rdf_li = $xml->getChildContent('rdf:RDF|rdf:Description|dc:creator|rdf:Bag|rdf:li');
$rdf_li_xml_lang = $xml->chilkatPath('rdf:RDF|rdf:Description|dc:description|rdf:Alt|rdf:li|(xml:lang)');
$rdf_li = $xml->getChildContent('rdf:RDF|rdf:Description|dc:description|rdf:Alt|rdf:li');
$i = 0;
$count_i = $xml->NumChildrenHavingTag('rdf:RDF|rdf:Description|dc:subject|rdf:Bag|rdf:li');
while ($i < $count_i) {
    $xml->put_I($i);
    $rdf_li = $xml->getChildContent('rdf:RDF|rdf:Description|dc:subject|rdf:Bag|rdf:li[i]');
    $i = $i + 1;
}

$xmpMM_DocumentID = $xml->getChildContent('rdf:RDF|rdf:Description|xmpMM:DocumentID');
$xmpMM_InstanceID = $xml->getChildContent('rdf:RDF|rdf:Description|xmpMM:InstanceID');
$pdf_Producer = $xml->getChildContent('rdf:RDF|rdf:Description|pdf:Producer');
$pdf_Keywords = $xml->getChildContent('rdf:RDF|rdf:Description|pdf:Keywords');
$xmpRights_WebStatement = $xml->getChildContent('rdf:RDF|rdf:Description|xmpRights:WebStatement');

?>