PHP Extension Requires Chilkat v11.7.0+

PDF Object Streams: generate, preserve or disable

See more PDF Optimization Examples

Demonstrates the objectStreams option. An object stream packs many small objects (dictionaries, not stream data) into one compressed stream, which is usually a worthwhile saving in a document with many pages or tags. "generate" (the default) packs them and writes a cross-reference stream; "preserve" keeps the file as it is -- packed if it already was, not packed if it was not; "disable" writes every object on its own with a classic cross-reference table, which is what a PDF 1.4 reader needs. Object streams require PDF 1.5 and are skipped for PDF/A-1. 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 grand_canyon_hiking_guide.pdf

$fac = new CkFileAccess();
$json = new CkJsonObject();
$jsonOut = new CkJsonObject();

//  generate: pack the objects (the default).
$pdf1 = new CkPdf();
$success = $pdf1->LoadFile('qa_data/pdf/grand_canyon_hiking_guide.pdf');
if ($success == false) {
    print $pdf1->lastErrorText() . "\n";
    exit;
}

$json->UpdateString('objectStreams','generate');
$success = $pdf1->Optimize('optimize',$json,$jsonOut);
if ($success == false) {
    print $pdf1->lastErrorText() . "\n";
    exit;
}

$success = $pdf1->WriteFile('qa_output/grand_canyon_objstm_generate.pdf');
if ($success == false) {
    print $pdf1->lastErrorText() . "\n";
    exit;
}

print 'generate: ' . $fac->FileSize('qa_output/grand_canyon_objstm_generate.pdf') . ' bytes, objects packed: ' . $jsonOut->IntOf('actions.objectStreams.count') . "\n";

//  disable: every object on its own, with a classic cross-reference table.
$pdf2 = new CkPdf();
$success = $pdf2->LoadFile('qa_data/pdf/grand_canyon_hiking_guide.pdf');
if ($success == false) {
    print $pdf2->lastErrorText() . "\n";
    exit;
}

$json->UpdateString('objectStreams','disable');
$success = $pdf2->Optimize('optimize',$json,$jsonOut);
if ($success == false) {
    print $pdf2->lastErrorText() . "\n";
    exit;
}

$success = $pdf2->WriteFile('qa_output/grand_canyon_objstm_disable.pdf');
if ($success == false) {
    print $pdf2->lastErrorText() . "\n";
    exit;
}

print 'disable:  ' . $fac->FileSize('qa_output/grand_canyon_objstm_disable.pdf') . ' bytes' . "\n";

//  preserve: leave the file's own structure alone.  Use it when the output must stay readable by
//  whatever reads the input today.
$pdf3 = new CkPdf();
$success = $pdf3->LoadFile('qa_data/pdf/grand_canyon_hiking_guide.pdf');
if ($success == false) {
    print $pdf3->lastErrorText() . "\n";
    exit;
}

$json->UpdateString('objectStreams','preserve');
$success = $pdf3->Optimize('optimize',$json,$jsonOut);
if ($success == false) {
    print $pdf3->lastErrorText() . "\n";
    exit;
}

$success = $pdf3->WriteFile('qa_output/grand_canyon_objstm_preserve.pdf');
if ($success == false) {
    print $pdf3->lastErrorText() . "\n";
    exit;
}

print 'preserve: ' . $fac->FileSize('qa_output/grand_canyon_objstm_preserve.pdf') . ' bytes' . "\n";

?>