Sustainability of Digital Formats
Planning for Library of Congress Collections
Sustainability of Digital Formats
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| Introduction | Sustainability Factors | Content Categories | Format Descriptions | Contact | |
| Full name | DivxX Video Codec, Version 5 |
| Description | Bitstream encoding for video initially developed by the French video engineer Jérôme Rota, aka Gej. The DivX (formerly DivXNetworks) Web site describes the encoding as based on the MPEG-4 standard; DivX version 5.0 was released in March 2002; version 5.1 during 2003. Note: DivX 6.x codecs were released beginning in late 2005; not yet investigated for this Web site. |
| Production phase | Generally used as an end-user delivery format. |
| Relationship to other formats | |
| Has earlier version | DivX_4 video codec, not documented at this time. |
| Has later version | DivX_6 video codec, not documented at this time. |
| Used by | AVI_DivX, AVI, DivX Codec |
| LC experience or existing holdings | |
| LC preference |
| Disclosure | Proprietary standard with some public documentation |
| Documentation | The helpful "near-specification" The Official DivX 5.1 Guide is available (as of May 2010) from the Internet Archive Wayback Machine (http://web.archive.org/web/20050408161644/http://www.divx.com/support/guides/DivXGuide51.pdf) |
| Adoption | An FAQ from the Ligos Corporation, distributors of the competing Indeo codec, includes this statement: "Many video files being distributed over the Internet use the DivX AVI format . . . ." |
| Licensing and patent claims | DivX software is distributed under license from the company; then compiler of this page is uncertain as to whether the codec itself is protected. In 2006, a page on the Web site (http://www.divx.com/divx/licensing/; not available in May 2010) described licensing arrangements as free for personal use and fee-based for commercial uses. Additional information available in the Wikipedia article on DivX, consulted in May 2010. |
| Transparency | Depends upon algorithms and tools to read; will require sophistication to build tools. |
| Self-documentation | Not applicable; provided by wrapper formats. |
| External dependencies | None. |
| Technical protection considerations | According to the Wikipedia article on DivX (possibly referring to version 6.x), "DivX Video on Demand (DivX VOD) is DivX's version of digital rights management (DRM), which allows content owners to control distribution in an effort to thwart piracy." |
| Normal rendering | Not applicable |
| Clarity (support for high image resolution) | Moderate, varies according to levels of compression and picture size; the maximum of which is about four megapixels, with no dimension exceeding 8,188 pixels. Does not support interlaced playback. More information on picture size and quality is provided in the Wikipedia article on DivX, although this may feature information about version 6.x. |
| Fidelity (support for high audio resolution) | Not applicable. |
| Support for multiple sound channels | Not applicable. |
| Functionality beyond normal video rendering | Not applicable. |
| Tag type | Value | Note |
| Filename Extension | n/a | |
| Internet Media Type | n/a | |
| Magic numbers | n/a | |
| Microsoft FOURCC | DIVX, DIV3, DIV4, DX50 | Used when this codec is wrapped in Microsoft file formats, e.g., AVI and ASF. Only the first of these FOURCC codes (DIVX) is listed at the Microsoft registry. The others are listed elsewhere, presumably the numbered FOURCCs identify DivX versions 3 [if it existed], 4, and 5. |
| General | |
| History | The Official DivX 5.1 Guide indicates that Jérôme Rota began work on DivX in 1999, with an eye toward fitting a feature film on a compact disk and/or making it easy to disseminate films on the web. DivXNetworks was founded in 2000. In 2001, DixXNetworks launched a "covert" website that led to the creation of OpenDivX, an open source project eventually called XVID. DivX 4 was released in 2001, DivX5 in March 2002, and version 5.1 in the latter half of 2003. The version 6.x series, launched in December 2005, is listed on the version history page at the DivX Web site (as of May 2010).
The Digital Digest DivX FAQ reports "The original DivX 3.xx codec is based on Microsoft's MPEG-4 V3 codec (ASF was based on MPEG-4 V2). The reason why the codec was "hacked" and re-distributed is because Microsoft's codec did not allow one to encode to AVI (they only wanted people to encode to ASF/WMV), which is far from being convenient. The DivX 3.xx codec also includes hacked versions of a MP3 codec and a WMA codec. . . . The new DivX 4.x codec has nothing to do with Microsoft - it has been developed entirely from scratch." The same is no doubt true of the DivX 5 codec. |
URLs
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URLs
• The Official DivX 5.1 Guide, is a "how to" guide for software users but offers a helpful stand-in for specifications; available (as of May 2010) from the Internet Archive Wayback Machine (http://web.archive.org/web/20050408161644/http://www.divx.com/support/guides/DivXGuide51.pdf).
• DivX web site
• DivX FAQ from the Digital Digest.
• John McGowan's AVI Overview: Audio and Video Codecs (http://www.jmcgowan.com/avicodecs.html).
• Wikipedia article on DivX (http://en.wikipedia.org/wiki/DivX
• PowerPoint overview of the technology (www.uio.no/studier/emner/matnat/ifi/INF5080/v04/mkt03d_divx.pdf)
• Microsoft registry of FOURCC codes and WAVE format indicators (http://msdn2.microsoft.com/en-us/library/ms867195.aspx). The archived 2001 version of this registry is at http://www.microsoft.com/whdc/archive/fourcc.mspx.
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