LibrePDF/OpenPDF
OpenPDF
OpenPDF ist eine Java-Bibliothek und ein Dokumentenprozessor zum Erstellen, Bearbeiten, Rendern und Verschlüsseln von PDF-Dokumenten. Sie fungiert als Toolkit, um neue Dateien von Grund auf zu generieren, bestehende Dokumentstrukturen zu modifizieren und Textinhalte zu extrahieren.
Das Projekt enthält eine dedizierte Engine zur Transformation von HTML- und CSS-Inhalten in PDF-Dokumente durch das Parsen von Markup und die Anwendung von Styles. Zudem bietet es eine Rendering-Engine, um PDF-Seiten für Thumbnails und Vorschauen in Bildformate zu konvertieren, sowie ein Sicherheits-Utility zum Schutz von Inhalten durch Dokumentenverschlüsselung.
Die Bibliothek unterstützt das Hinzufügen von Grafiken, Tabellen und mehrseitigen TIFF-Bildern. Sie bewältigt komplexe Typografie durch Unterstützung für Multi-Byte-Zeichen, bidirektionalen Text und nicht-lateinische Schriften.
Die Software nutzt die plattformübergreifende Java-Laufzeitumgebung und enthält Pakete, um die Dokumentenverarbeitung in Android-Umgebungen zu ermöglichen.
Features
- PDF Document Generation - Generates new PDF documents from scratch using a programmatic Java interface.
- PDF Document Management - Offers a comprehensive toolkit for generating, editing, and manipulating PDF files and their structures.
- PDF Libraries - Provides a comprehensive Java library for creating, editing, rendering, and encrypting PDF documents.
- HTML to PDF Converters - Provides an engine to render HTML and CSS content into portable PDF documents.
- PDF Content Editing - Enables the modification of existing PDF files by altering text content and managing pages.
- PDF Tables and Graphics - Supports the embedding of images, vector graphics, and structured data tables to visualize information.
- PDF Text Extraction - Parses binary PDF files to extract raw text strings for processing and analysis.
- PDF Typography - Adds text using various styles and fonts to support complex glyphs and right-to-left scripts.
- HTML Layout Parsers - Features a layout parser that transforms HTML and CSS into a structured geometric box tree for PDF generation.
- PDF and HTML Content Extraction - Opens and parses existing PDF documents to extract content into standardized objects for modification.
- Compressed PDF Streams - Writes document content as sequential data streams using Flate or Brotli compression to minimize file size.
- Multi-Language Rendering - Provides support for rendering diverse scripts and multi-byte character sets to ensure correct visual display across different languages.
- PDF Internal Structure Access - Provides direct access to the internal PDF object model, including cross-reference tables and document trailers.
- Complex Script Renderers - Computes correct glyph positioning and reordering for accented letters, bidirectional text, and non-Latin scripts.
- PDF to Image Rendering - Transforms PDF page content into raster image formats for use in interfaces and files.
- PDF Security and Signing - Implements PDF security through password protection and encryption to restrict document access.
- PDF Encryptions and Decryptions - Implements encryption and decryption mechanisms to protect sensitive PDF files from unauthorized access.
- Document Encryption - Secures sensitive PDF content using encryption to restrict unauthorized access.
- Document Generation DSLs - Allows the creation of documents using a builder syntax and extension functions to define structure and content.
- Font Embedding - Embeds subsetted font data and glyph mappings to ensure consistent typography across different PDF viewers.
- Coordinate-Based Layouts - Provides a coordinate-based layout system to position text and graphics on a precise two-dimensional grid.
- Bidi Layout Engines - Implements bidirectional layout engines to correctly position right-to-left scripts within PDF documents.
- PDF Processing - Open-source fork for programmatic PDF creation.
