Name : Leon Bottou E-mail : leonb&research.att.com MIME media type name : Image MIME subtype name : Vendor Tree - vnd.djvu Required parameters : none Optional parameters : none Encoding considerations : Binary or base64 is preferred. Security considerations : The specified components of the DjVu media format are of a descriptive nature and provide information that is useful to facilitate viewing and rendering of images by a recipient. As such, the DjVu media format does not in itself create additional security risks, since the fields are not used to induce any particular behavior by the recipient application. The DjVu media format has an extensible structure, so that it is theoretically possible that fields could be defined in the future which could be used to induce particular actions on the part of the recipient, thus presenting additional security risks, but this type of capability is not supported in the referenced DjVu specification. The DjVu media format does not specify a way to certify the authenticity of a document. Such a warranty might be provided by other means, for instance by signing the complete contents of an email containing DjVu media data. Interoperability considerations : DjVu represents document images using multiple layers encoded using different encoding methods. Future extensions of the DjVu format might define new encoding methods that would not be supported by older viewers. DjVu viewer implementations should detect and report this condition by comparing the DjVu version number embedded in every DjVu media file with the highest supported DjVu version number. They should then decode those layers they can decode and display these layers only. Published specification : * SPECIFICATION OF THE DJVU IMAGE COMPRESSION FORMAT. 1999-04-29, AT&T Labs. This is the original specification of DjVu. Copies are available at the following URLs: http://www.djvuzone.org/djvu/sci/djvuspec (DjVu) http://djvu.sourceforge.net/specs/djvu2spec.djvu (DjVu) http://djvu.sourceforge.net/specs/djvu2spec.ps.gz (ps.gz) * DIFFERENCES BETWEEN DJVU2 and DJVU3 2001/10/22, Leon Bottou, AT&T Labs This is a compilation of the changes between the AT&T specification and the currently released Lizardtech souce code. http://djvu.sourceforge.net/specs/djvu3changes.txt (Text) * DJVU SOURCE CODE Various open-source implementations (GNU Public License) have been made available by both AT&T-Labs Research and Lizardtech, Inc. These files are availablke at the following URL: http://sourceforge.net/project/djvu Applications which use this media : Imaging, messaging, web publishing. Additional information : 1. Magic number(s) : ASCII "FORM" at offset 4 and ASCII "DJVU" or "DJVM" or "PM44" or "BM44" at offset 12. 2. File extension(s) : djvu, djv 3. Macintosh file type code : DJVU 4. Object Identifiers: General information on DjVu is available at http://www.djvuzone.org . Commercial software is available from Lizardtech, Inc at http://www.lizardtech.com . Open source software (encoders, decoders, viewers, utilities) is available at http://djvu.sourceforge.net . Person to contact for further information : 1. Name : Leon Bottou 2. E-mail : Intended usage : Common DjVu is a web-centric format for distributing documents and images. DjVu is designed for distributing scanned documents, digital documents, or high-resolution pictures. DjVu content downloads faster, displays and renders faster, looks nicer on a screen, and consume less client resources than competing formats. DjVu images display instantly and can be smoothly zoomed and panned with no lengthy re-rendering. DjVu is used by hundreds of academic, commercial, governmental, and non-commercial web sites around the world. Author/Change controller : Other contact persons: - Leon Bottou - Yann Le Cun (created 17 Jan 2002)