Perl 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. 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 grand_canyon_hiking_guide.pdf

$fac = chilkat::CkFileAccess->new();
$json = chilkat::CkJsonObject->new();
$jsonOut = chilkat::CkJsonObject->new();

#  generate: pack the objects (the default).
$pdf1 = chilkat::CkPdf->new();
$success = $pdf1->LoadFile("qa_data/pdf/grand_canyon_hiking_guide.pdf");
if ($success == 0) {
    print $pdf1->lastErrorText() . "\r\n";
    exit;
}

$json->UpdateString("objectStreams","generate");
$success = $pdf1->Optimize("optimize",$json,$jsonOut);
if ($success == 0) {
    print $pdf1->lastErrorText() . "\r\n";
    exit;
}

$success = $pdf1->WriteFile("qa_output/grand_canyon_objstm_generate.pdf");
if ($success == 0) {
    print $pdf1->lastErrorText() . "\r\n";
    exit;
}

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

#  disable: every object on its own, with a classic cross-reference table.
$pdf2 = chilkat::CkPdf->new();
$success = $pdf2->LoadFile("qa_data/pdf/grand_canyon_hiking_guide.pdf");
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

$json->UpdateString("objectStreams","disable");
$success = $pdf2->Optimize("optimize",$json,$jsonOut);
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

$success = $pdf2->WriteFile("qa_output/grand_canyon_objstm_disable.pdf");
if ($success == 0) {
    print $pdf2->lastErrorText() . "\r\n";
    exit;
}

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

#  preserve: leave the file's own structure alone.  Use it when the output must stay readable by
#  whatever reads the input today.
$pdf3 = chilkat::CkPdf->new();
$success = $pdf3->LoadFile("qa_data/pdf/grand_canyon_hiking_guide.pdf");
if ($success == 0) {
    print $pdf3->lastErrorText() . "\r\n";
    exit;
}

$json->UpdateString("objectStreams","preserve");
$success = $pdf3->Optimize("optimize",$json,$jsonOut);
if ($success == 0) {
    print $pdf3->lastErrorText() . "\r\n";
    exit;
}

$success = $pdf3->WriteFile("qa_output/grand_canyon_objstm_preserve.pdf");
if ($success == 0) {
    print $pdf3->lastErrorText() . "\r\n";
    exit;
}

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