# DjView

> software to view DjVu documents

**Wikidata**: [Q12809115](https://www.wikidata.org/wiki/Q12809115)  
**Source**: https://4ort.xyz/entity/djview

## Summary
DjView is a free software application specifically designed to view DjVu documents. Often referred to as DjView4, it serves as a graphical interface that depends on the DjVuLibre library to render files. The software is widely distributed across major open-source operating systems, including Linux distributions and BSD variants.

## Key Facts
- **Primary Function:** Software to view DjVu documents.
- **Software Type:** Free software; it is copyrighted but distributed under terms allowing users to freely run, study, change, and distribute it.
- **Aliases:** DjView4.
- **Latest Recorded Version:** 4.12 (released November 20, 2020).
- **Previous Version:** 4.10.6 (released February 29, 2016).
- **Official Website:** http://djvu.sourceforge.net/djview4.html
- **Source Code Repository:** Hosted at https://git.code.sf.net/p/djvu/djview-git.
- **Core Dependency:** DjVuLibre software library.
- **Google Knowledge Graph ID:** /g/1ylhld8ys.
- **Repology Project Name:** djview.

## FAQs
### What is DjView used for?
DjView is a specialized viewer for documents encoded in the DjVu format. It provides the graphical interface necessary to open and read these files on a computer.

### Is DjView free to use?
Yes, DjView is classified as free software. This means it is distributed under terms that allow users to freely run, study, change, and distribute the software and any modified versions.

### What operating systems support DjView?
The software has specific packages or ports available for a wide range of open-source systems, including Arch Linux, Debian, Fedora, Gentoo, Mageia, SlackBuilds, FreeBSD, OpenBSD, and NetBSD. It is also available via Homebrew.

### What are the differences between DjView versions?
The source data identifies two specific versions: 4.10.6, which was released on February 29, 2016, and a later version, 4.12, released on November 20, 2020.

## Why It Matters
DjView matters because it acts as a primary access point for the DjVu document format within the free software ecosystem. As a viewer dependent on the DjVuLibre library, it bridges the gap between the compressed file format and the end-user. Its widespread inclusion in major package repositories—from Debian and Arch Linux to FreeBSD and Homebrew—demonstrates its status as a standard tool for accessing DjVu files on open-source platforms. By adhering to the principles of free software, it ensures that users are not restricted from modifying or redistributing the tool, fostering a collaborative environment for its maintenance and improvement.

## Notable For
- Being a dedicated viewer for the **DjVu** document format.
- Ubiquitous availability across **Linux and BSD distributions**, with dedicated ports and packages for nearly every major system.
- Classification as **Free Software**, distinguishing it from proprietary viewers.
- Active maintenance into the **2020s**, with version 4.12 released in late 2020.
- Integration with the **DjVuLibre** backend, ensuring compatibility with the core library.

## Body

### Definition and Classification
DjView is a computer program categorized as **free software**. It functions as a viewer for DjVu documents, a format often used for high-resolution images of scanned documents. As free software, it is defined by the "four freedoms": the ability to run, study, change, and distribute the software, including modified versions. It is the opposite of proprietary software. The application is explicitly copyrighted but licensed to permit these freedoms.

### Technical Architecture
The software operates as a frontend that relies on the **DjVuLibre** software library. This dependency is essential for decoding and rendering the DjVu format. The source code is maintained in a Git repository located at `https://git.code.sf.net/p/djvu/djview-git`.

### Version History
Development of DjView has produced several distinct releases tracked in the provided data:
- **Version 4.12:** The most recent version listed, released on **November 20, 2020**.
- **Version 4.10.6:** An earlier stable release dated **February 29, 2016**.

### Ecosystem and Distribution
DjView is deeply integrated into the open-source software ecosystem, with official packages available for a variety of operating systems. This ensures that users can easily install it through native package managers.
- **Linux Distributions:**
    - **Arch Linux:** Package name `djview`.
    - **Debian (Stable):** Package name `djview`.
    - **Fedora:** Package name `djview4`.
    - **Gentoo:** Package name `app-text/djview`.
    - **Mageia:** Package name `djview4`.
    - **SlackBuilds:** Package located in `graphics/djview4`.
- **BSD Systems:**
    - **FreeBSD:** Port located at `graphics/djview4`.
    - **OpenBSD:** Port located at `graphics/djview4`.
    - **NetBSD:** Package ID `graphics/djview4`.
- **macOS:**
    - **Homebrew:** Formula name `djview4`.

### Project Identifiers
The project is tracked under the Repology project name `djview`. It has a Google Knowledge Graph ID of `/g/1ylhld8ys` and maintains a Turkish language Wikipedia page. The official website is hosted at `http://djvu.sourceforge.net/djview4.html`.

## References

1. [Source](https://sourceforge.net/projects/djvu/files/DjView/4.10/)
2. [Source](https://sourceforge.net/projects/djvu/files/DjView/4.12/)
3. [Source](http://djvu.sourceforge.net/djview4.html)