ما هو DJVU؟ شرح تنسيق صورة وثيقة DjVu

تعلم ما هو ملف DjVu: تنسيق صورة وثيقة مضغوط تم تطويره في مختبرات AT&T للصفحات والكتب الممسوحة ضوئيًا، مما يوفر ملفات صغيرة مع قابلية قراءة عالية.

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Document

ما هو DJVU؟ شرح تنسيق صورة وثيقة DjVu

DjVu هو تنسيق صورة وثيقة مضغوط مصمم للصفحات والكتب والمستندات الممسوحة ضوئيًا.

آخر تحديث:

Year1996
TypeDocument image
UsageScanned documents

What is it?

DjVu (pronounced deja vu) is a compressed image format designed primarily for storing scanned documents, especially those combining text, line drawings and photographs. It was developed by researchers at AT&T Labs in the mid-1990s and later commercialized by LizardTech.

DjVu separates a scanned page into layers, typically a high-resolution text/line mask and lower-resolution background and foreground images, then compresses each appropriately. This layered approach produces files that are often much smaller than equivalent PDFs or TIFFs while keeping text sharp.

Technical Specifications

DeveloperAT&T Labs (later LizardTech / Caminova)
File Extension.djvu, .djv
MIME Typeimage/vnd.djvu
Released1996
StandardProprietary origin; open DjVuLibre implementation

Pros & Cons

Advantages

ضغط عالي جدًا

DjVu's layered compression makes scanned pages far smaller than comparable PDF or TIFF files while keeping text readable.

نص واضح على المسح الضوئي

Separating the text layer preserves crisp characters even at aggressive compression, ideal for scanned books and documents.

أدوات مفتوحة المصدر

The DjVuLibre project provides free, open implementations for creating, viewing and converting DjVu files.

Disadvantages

دعم محدود من التيار الرئيسي

Most browsers and office apps do not open DjVu natively, so a dedicated viewer or plugin is usually required.

تراجع في التبني

PDF has become the dominant document format, leaving DjVu used mainly in digital libraries and archives.

When to Use It

DjVu is used where scanned documents must stay small yet readable.

المكتبات الرقمية

Archives and libraries store scanned books and journals in DjVu to save space.

توزيع الكتب الممسوحة

Large scanned volumes are shared as compact DjVu files for easier download.

أرشفة الوثائق

Historical and technical documents are preserved as space-efficient DjVu scans.

How to open a DJVU file

DJVU files are typically handled by a range of software categorized into professional tools, free or open-source applications, browser-based viewers, and built-in system tools. Professional tools cater to users needing advanced features for editing and managing large document collections, while free and open-source options are ideal for casual users or those on a budget. Browser-based viewers offer convenience for quick access without installation, and built-in tools provide basic functionality for users who may not need extensive features.

When selecting software for DJVU, key decision factors include fidelity in rendering images, the need for editing capabilities versus simple viewing, and the overall cost model of the software. Platform compatibility is also crucial, as some applications are limited to specific operating systems. Users should consider export needs, as converting DJVU files to more common formats may sometimes be the better option, especially if compatibility with other software is required.

DjView 1.0.0

Windows, macOS, LinuxFree (GPL)

DjView is a dedicated viewer for DJVU files, designed to provide high-quality rendering and navigation through documents. It supports features like text selection and image extraction, making it suitable for users who primarily need to view and interact with DJVU content.

الميزات الرئيسية
  • High-quality image rendering
  • Text selection and copying
  • Bookmarking and annotation support
  • Multi-page document navigation
  • Image extraction capabilities
نقاط القوة
  • Open-source and completely free
  • Cross-platform compatibility
  • Lightweight with fast performance
القيود
  • Limited editing capabilities
  • Basic interface may lack advanced features

يصدّر إلى: PDF, PNG, TIFF

الأفضل لـ: Choose DjView for a free, efficient viewer focused on high-quality DJVU rendering.

زيارة DjView →

WinDjView 2.0

WindowsFree (GPL)

WinDjView is a Windows-specific viewer for DJVU files that offers a user-friendly interface and a range of features tailored for document navigation. It excels in rendering fidelity and includes options for annotations and bookmarks, making it suitable for both casual and professional users.

الميزات الرئيسية
  • Tabbed document interface
  • Annotation and highlighting tools
  • Full-screen and presentation modes
  • Text search functionality
  • Automatic updates for new features
نقاط القوة
  • Intuitive user interface
  • Robust annotation features
  • Fast and responsive performance
القيود
  • Windows-only platform
  • Limited export options compared to others

يصدّر إلى: PDF, TIFF

الأفضل لـ: WinDjView is ideal for Windows users seeking a feature-rich DJVU viewer with annotation capabilities.

زيارة WinDjView →

DjVuLibre 3.5.27

Windows, macOS, LinuxFree (GPL)

DjVuLibre is a comprehensive toolkit for working with DJVU files, providing both viewing and conversion capabilities. It is particularly useful for users who need to manipulate DJVU documents or convert them into other formats while maintaining high fidelity.

الميزات الرئيسية
  • Command-line tools for batch processing
  • High-quality DJVU rendering
  • Conversion to PDF and other formats
  • Support for OCR (Optical Character Recognition)
  • Image compression and optimization tools
نقاط القوة
  • Powerful command-line functionality
  • Supports OCR for text extraction
  • Flexible for both viewing and editing
القيود
  • Steeper learning curve for beginners
  • Less user-friendly interface

يصدّر إلى: PDF, TIFF, PNG, JPG

الأفضل لـ: DjVuLibre is best for advanced users needing comprehensive tools for editing and converting DJVU files.

زيارة DjVuLibre →

Online DJVU Viewer N/A

All (browser)Free

Online DJVU Viewer is a web-based tool that allows users to view DJVU files without installing any software. It is convenient for quick access to documents and supports basic navigation features, making it suitable for users who need immediate access to DJVU files.

الميزات الرئيسية
  • Instant access via web browser
  • Basic navigation and zooming tools
  • No installation required
  • Supports multi-page documents
  • Compatible with various devices
نقاط القوة
  • No software installation needed
  • Accessible from any device
  • Quick and easy to use
القيود
  • Limited features compared to desktop apps
  • Dependent on internet connection

يصدّر إلى: N/A

الأفضل لـ: Use Online DJVU Viewer for quick, hassle-free access to DJVU files without installation.

زيارة Online DJVU Viewer →

Convert DJVU Files Free

Use our free online document converter to convert DJVU and other formats - no signup, no watermarks.

Try Document Converter Free

References

  1. DjVu - Wikipedia
  2. Media Type image/vnd.djvu - FileFormat.Info
  3. DjVu and DjVuLibre manual page