README

Decoder library for standard PDF stream filters.

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Overview

tc-lib-pdf-filter decodes compression and transformation filters defined by the PDF specification.

It is intended for both generation and parsing workflows where PDF streams must be encoded or decoded according to the standard filter pipeline. By isolating filter logic in one component, callers get predictable behavior and easier testing across different document inputs.

Features

PDF Filters

• FlateDecode, LZWDecode, RunLengthDecode
• ASCIIHexDecode, ASCII85Decode
• CCITTFaxDecode, DCTDecode, JPXDecode, JBIG2Decode

API Design

• Decode one filter or apply multiple filters in sequence
• Pure-PHP implementation suitable for parser integration
• Typed exceptions for unknown/invalid filter handling

Requirements

• PHP 8.2 or later
• Extensions: zlib, pcre
• Composer

Installation

composer require tecnickcom/tc-lib-pdf-filter

Quick Start

<?php

require_once __DIR__ . '/vendor/autoload.php';

$filter = new \Com\Tecnick\Pdf\Filter\Filter();
$decoded = $filter->decodeAll(['ASCIIHexDecode', 'FlateDecode'], $data);

Development

make deps
make help
make qa

Packaging

make rpm
make deb

For system packages, bootstrap with:

require_once '/usr/share/php/Com/Tecnick/Pdf/Filter/autoload.php';

Contributing

Contributions are welcome. Please review CONTRIBUTING.md, CODE_OF_CONDUCT.md, and SECURITY.md.

Contact

Nicola Asuni - info@tecnick.com