Djvu is an image compression technique and file format developed in 1996 by AT&T Labs to improve compression of photos, images, and documents compared to PDF. It divides documents into black text, background graphics, and foreground color layers to achieve much smaller file sizes than PDF - often half the size or less. Djvu allows high resolution documents to be distributed online and viewed on computers and mobile devices through lightweight software.

1. An improvement over compression of photo,image and documents
DJVU

2. INTRODUCTION
• The Djvu technology was originally developed by Yann LeCun, Léon
Bottou, Patrick Haffner, and Paul G. Howard at AT&T Laboratories in
1996.
• Due to its declared higher compression ratio (and thus smaller file
size) and the ease of converting large volumes of text into Djvu
format, and because it is an open file format, some independent
technologists have historically considered it superior to .pdf. .
• DJVU is another replacement over “.pdf ” file because it compression
technique is much enhance and the compressed file taking less space
rather than a PDF file.
• Its size is much smaller than PDF files and near about ½ with the “.pdf
” .

3. WHAT IS DJVU…….?
• A compression technique , a file format and a software platform for
distribution of scanned document ,images and many more(scanned or
digitally produced content in color , gray or b/w ) over the
web(internet).
• DjVu (pronounced "déjà vu") is a new image compression technology
developed since 1996 at AT&T Labs to solve precisely that problem.
• DjVu allows the distribution on the Internet of very high resolution
images of scanned documents, digital documents, and photographs.
• DjVu allows content developers to scan high-resolution color pages of
books, magazines, catalogs, manuals, newspapers , historical or
ancient documents, and make them available on the Web.

4. MAIN FEATURES OF DJVU
High compression format of the document
Article quality
Page streaming technology
Body of the document search and content integration
Preview

5. AN OVERVIEW OF DJVU
Web Users
Mobile UsersBook Old Book/Paper
Magazine
Photo
Off-line Paper/
Digital Document
High Compression
One Source format
POD Service
Multi-Use

6. HOW IT WORKS
Original layer

7. • It converts the original layer into three different layer .
• Black layer- contains a black and white text layout of the
document.
• Background layer- it contains all the image (grapich) in the
document.
• Foreground layer –it also contains the color information of the
black layer .
so the document is divide in three sub layers and
these layers are much smaller than the original layer.

8. THE KEY ELEMENTS OF DJVU
Stability
In 1999, the U.S. AT & T DjVu technology since published it is recognised as a rich
Document creation.
Lightweight
Content
Quality
PDF file size compared to the average 1/5 to 1/20 as a compact si
Reader-based: Acrobat PDF read about 20MB vs. A 900KB DjVu viewer
Compressed Size maintain the best quality for the lowest content
 DjVu segmentation technology
Access
Rate
Acess rate is much higher than the pdf because is low cach space required for
Loading and viewing.

9. DJVU AND OTHERS
TIFF JPEG PDF DjVu
46 MB
1.3 MB 1.3 MB
56 KB
A typical 400dpi
Magazine pages scanned in 24 bit color

10. DJVU OVER PDF
• Much smaller file size than scanned documents encapsulated in PDF
• Smaller file size than digitally produced PDF if the document contains
pictures.
• Total portability/compatibility (no font problems).
• Somewhat smaller file size for purely textual digital documents.
• Better integration with the Web's navigation paradigm
• Fast display, panning and zooming.
• Very lightweight plug-in/viewer (600KB for DjVu versus 6MB for Acrobat
Reader) with self-installation capability.

11. ADVANTAGES
• Hyperlink Support
• Windows applications available on the ActiveX-based plug-in for
• Web pages can be inserted into DjVu documents (JPEG images, such as
dealing with)
• To meet the needs of the user can customize the viewer
• Progressive page rendering.
• Direct access to any page Pages.
• Streaming unit (page cache) support.
• Real-time zooming and panning.

12. FUTURE SCOPE
• Replacement of pdf
• Small picture uploading.
• Can be used for Historical Document repositories.

13. Thank you