Dj. Vu - Wikipedia. This article is about a computer file format. For a computer- assisted translation software tool, see Déjà Vu (software). Dj. Vu (DAY- zhah- VOO, like English "déjà vu"[3]) is a computerfile format designed primarily to store scanned documents, especially those containing a combination of text, line drawings, indexed color images, and photographs. It uses technologies such as image layer separation of text and background/images, progressive loading, arithmetic coding, and lossy compression for bitonal (monochrome) images. This allows high- quality, readable images to be stored in a minimum of space, so that they can be made available on the web. Dj. Vu has been promoted as an alternative to PDF, promising smaller files than PDF for most scanned documents.[4] The Dj. Vu developers report that color magazine pages compress to 4. B, black- and- white technical papers compress to 1. B, and ancient manuscripts compress to around 1. B; a satisfactory JPEG image typically requires 5. B.[5] Like PDF, Dj. Vu can contain an OCR text layer, making it easy to perform copy and paste and text search operations. Free browser plug- ins and desktop viewers from different developers are available from the djvu. · Free Download Adobe Illustrator CC 2017.1 21.0.2 - Create resolution graphics and printed materials, and experiment with different shapes or effects. Dj. Vu is supported by a number of multi- format document viewers and e- book reader software on Linux (Okular, Evince) and Windows (Sumatra. PDF). Despite its advantages, Dj. Vu is not widely supported by scanning and viewing software. History[edit]The Dj. Vu technology was originally developed[5] by Yann Le. Cun, Léon Bottou, Patrick Haffner, and Paul G. Howard at AT& T Labs from 1. Due to its declared higher compression ratio (and thus smaller file size) and the ease of converting large volumes of text into Dj. Vu format, and because it is an open file format, it has been considered superior to PDF. Independent technologist Brewster Kahle in a 2. IT Conversations discussed the benefits of allowing easier access to Dj. Vu files.[6][7]The Dj. Download the free trial version below to get started. Double-click the downloaded file to install the software.Oracle acquired Sun Microsystems in 2010, and since that time Oracle's hardware and software engineers have worked side-by-side to build fully integrated systems and. Corel draw Windows 7 - Free Download Windows 7 corel draw - Windows 7 Download - Free Windows7 Download. Vu library distributed as part of the open- source package Dj. Vu. Libre has become the reference implementation for the Dj. Vu format. Dj. Vu. Libre has been maintained and updated by the original developers of Dj. Vu since 2. 00. 2.[8]The Dj. Vu file format specification has gone through a number of revisions: Revision history. Support status. Version. Release date. Notes. Unsupported. 1–1. Developmental versions by AT& T labs preceding the sale of the format to Lizard. Tech. Unsupported. Version 2. 0[1]April 1. Dj. Vu version 3. Dj. Vu changed from a single- page format to a multipage format. Older, still supported. Version 2. 1[1]September 1. Indirect storage format replaced. The searchable text layer was added. Older, still supported. Auction Draft Fantasy Football Software Ratings . Version 2. 2[1]April 2.Page orientation, color JB2. Unsupported. Version 2. July 2. 00. 2CID chunk. Unsupported. Version 2. February 2. 00. 3LTAnno chunk. Older, still supported. Version 2. 5[1]May 2. NAVM chunk. Support for Dj. Vu bookmarks (outlines) was added. Changes made by Versions 2. Current. Version 2. April 2. 00. 5Text/line annotations. Technical overview[edit]File structure[edit]The Dj. Vu file format is based on the Interchange File Format and is composed of hierarchically organized chunks. The IFF structure is preceded by a 4- byte AT& Tmagic number. Following is a single FORM chunk with a secondary identifier of either DJVU or DJVM for a single- page or a multi- page document, respectively. Chunk types[edit]Chunk identifier. Contained by. Description. FORM: DJVUFORM: DJVMDescribes a single page. Can either be at the root of a document and be a single- page document or referred to from a DIRM chunk. FORM: DJVMN/ADescribes a multi- page document. Is the document's root chunk. FORM: DJVIFORM: DJVMContains data shared by multiple pages. FORM: THUMFORM: DJVMContains thumbnails. INFOFORM: DJVUMust be the first chunk. Describes the page width, height, format version, resolution, gamma, and rotation. DIRMFORM: DJVMMust be the first chunk. References other FORM chunks. These chunks can either follow this chunk inside the FORM: DJVM chunk or be contained in external files. These types of documents are referred to as bundled or indirect, respectively. NAVMFORM: DJVMIf present, must immediately follow the DIRM chunk. Contains a BZZ- compressed outline of the document. Compression[edit]Dj. Vu divides a single image into many different images, then compresses them separately. To create a Dj. Vu file, the initial image is first separated into three images: a background image, a foreground image, and a mask image. The background and foreground images are typically lower- resolution color images (e. The background and foreground images are then compressed using a wavelet- based compression algorithm named IW4. The mask image is compressed using a method called JB2 (similar to JBIG2). The JB2 encoding method identifies nearly identical shapes on the page, such as multiple occurrences of a particular character in a given font, style, and size. It compresses the bitmap of each unique shape separately, and then encodes the locations where each shape appears on the page. Thus, instead of compressing a letter "e" in a given font multiple times, it compresses the letter "e" once (as a compressed bit image) and then records every place on the page it occurs. Optionally, these shapes may be mapped to UTF- 8 codes (either by hand or potentially by a text recognition system) and stored in the Dj.Vu file. If this mapping exists, it is possible to select and copy text.Since JBIG2 was based on JB2, both compression methods have the same problems when performing lossy compression. . Numbers may be substituted with similarly looking numbers (such as replacing 6 with 8) if the text was scanned at a low resolution prior to lossy compression. Format licensing[edit]Dj. Vu is an open file format with patents.[4] The file format specification is published, as well as source code for the reference library.[4] The original authors distribute an open- source implementation named "Dj. Vu. Libre" under the GNU General Public License. The rights to the commercial development of the encoding software have been transferred to different companies over the years, including AT& T Corporation, Lizard. Tech, Celartem and Cuminas. Support[edit]Despite its advantages, Dj. Vu is not widely supported by scanning and viewing software.[9] While viewers can be downloaded, opening Dj. Vu files is not implemented in most operating systems by default.[1. Sumatra. PDF (Windows) among others can manipulate Dj. Vu files. In 2. 00. Dj. Vu file format was chosen by the Internet Archive as a format in which its Million Book Project provides scanned public- domain books online (along with TIFF and PDF).[1. Wikimedia Commons, a media repository used by Wikipedia among others, conditionally permits PDF and Dj. Vu media files.[1. See also[edit]References[edit]^ abcdefghi. Dj. Vu File Format Version, By Jim Rile, Posted: Fri Feb 2. Planet. Dj. Vu^"Dj. Vu Licensing". Dj. Vu Sourceforge page. Sourceforge. net. Retrieved 2. 01. 1- 0. Dj. Vu. org - the premier menu for djvu resources". Retrieved 2. 01. 7- 0. What is Dj. Vu – Dj. Vu. org". Dj. Vu. Retrieved 2. 00. 9- 0. Léon Bottou; Patrick Haffner; Paul G. Howard; Patrice Simard; Yoshua Bengio; Yann Le Cun (1. High Quality Document Image Compression with Dj. Vu, 7(3): 4. 10–4. PDF). Journal of Electronic Imaging. ^Brewster Kahle (December 1. Universal Access to All Knowledge"(Audio; Speech at 1h: 3. Conversations Network. ^"Lizard. Tech To Open Source A Dj. Vu Java Viewer". ECM Connection. December 2. 00. 4. Retrieved 1. 8 August 2. Manual for Xerox/Visioneer One. Touch, widely used scanning software for business and home use, showing support for several file formats, but not Dj. Vu.^A test Dj. Vu file. Click on the image in the page to open the file on a computer with support for the . Image file formats – OLPC". Wiki. laptop. org. Retrieved 2. 00. 8- 0. Wikimedia Commons. Project scope: PDF and Dj. Vu. External links[edit].
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