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About DjVu:

DjVu is a web-centric format and software platform for distributing documents and images. DjVu can advantageously replace PDF, PS, TIFF, JPEG, and GIF 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.

DjVuLibre is an open source (GPL'ed) implementation of DjVu, including viewers, browser plugins, decoders, simple encoders, and utilities.

I actually don't know of any competing formats to jpeg other than this new microsoft one

http://www.djvuzone.org/

You do now!!! Although it is meant as a scanned document format it has available a compression similar to JPEG2000.

Isn't DjVu (http://www.djvuzone.org/) supposed to be an open source replacement for PDF already?

(Of course, you will still need to spend lots of time scanning, naming and classifying those pages. The ADF and 10yo nephew suggested in another post might be useful for that.)

DjVu offers very compact representation without the need to OCR the document (I've converted a 13 megs scanned PDF into a 600K DjVu which was much faster and easier to read), and optionally a "hidden text layer" if you want to OCR it to make it searchable.

(Of course, you will still need to spend lots of time scanning, naming and classifying those pages. The ADF and 10yo nephew suggested in another post might be useful for that.)

DjVu offers very compact representation without the need to OCR the document (I've converted a 13 megs scanned PDF into a 600K DjVu which was much faster and easier to read), and optionally a "hidden text layer" if you want to OCR it to make it searchable.

To scan and store hand-written notes it might be better to use DJVU format http://djvulibre.djvuzone.org/. You can find free readers for almost every platform (including Zaurus!) and filesize is very small despite the good quality.

You can also convert to/from PDF and PS using a free (non-gpl but open source license) gs driver from AT&T.

And it would be nice if djvu was that open.

However, notice how there isn't a free software pdf to djvu converter or reverse. It would seem like an obvious tool. This site has one where you can upload it: http://any2djvu.djvuzone.org/

One exists but they can't legally distribute it. See here for details: http://djvulibre.djvuzone.org/gsdjvu.html

From that link:

"Lizardtech then discovered that the DjVuDigital license they have from AT&T is different. The main DjVu agreement requires Lizardtech to make an open source release of the DjVu Reference Library. The DjVuDigital agreement apparently prevents Lizardtech to distribute the source code of GSDjVu. Quite curious for a derivative of Ghostscript!

We contacted AT&T Intellectual Property (IP) division and we asked them to correct this apparently benign situation. Alas AT&T has been suffering much in the last few years. Workforce reductions are frequent and painful. Nobody in the IP division wants to do the work and take the risk to open source a piece of code that does not seem to be central to the company business.

For all we know AT&T does not even care about GSDjVu. There is no-one left in AT&T who knows the DjVuDigital code, let alone how to improve it. Were it available as part of DjVuLibre instead of rotting on a shelf, it could be used to help academics, librarians, researchers, scientists, and students disseminate knowledge and culture. "

There are licensing problems with djvu...

And it would be nice if djvu was that open.

However, notice how there isn't a free software pdf to djvu converter or reverse. It would seem like an obvious tool. This site has one where you can upload it: http://any2djvu.djvuzone.org/

One exists but they can't legally distribute it. See here for details: http://djvulibre.djvuzone.org/gsdjvu.html

From that link:

"Lizardtech then discovered that the DjVuDigital license they have from AT&T is different. The main DjVu agreement requires Lizardtech to make an open source release of the DjVu Reference Library. The DjVuDigital agreement apparently prevents Lizardtech to distribute the source code of GSDjVu. Quite curious for a derivative of Ghostscript!

We contacted AT&T Intellectual Property (IP) division and we asked them to correct this apparently benign situation. Alas AT&T has been suffering much in the last few years. Workforce reductions are frequent and painful. Nobody in the IP division wants to do the work and take the risk to open source a piece of code that does not seem to be central to the company business.

For all we know AT&T does not even care about GSDjVu. There is no-one left in AT&T who knows the DjVuDigital code, let alone how to improve it. Were it available as part of DjVuLibre instead of rotting on a shelf, it could be used to help academics, librarians, researchers, scientists, and students disseminate knowledge and culture. "

There are licensing problems with djvu...

Actually, I was mildly pissed when I found out about the name... I was looking for a business name at the time and... well, that became not a choice.

But you've just compared a complete storage system encompassing fonts, vector graphics, images, form fields and the whole kitchensink - with an image compression app.

This appears to describe more than that, and describes metadata capability that sounds like it could handle the functionaliy you describe if anyone wanted to standardize a format that would fit within the DJVU container.

Depends on what you need a document format for. If I want to put complete job information for a print run into a document and e-mail it to a printer, of course a PDF is the format of choice. That's what printers are set up for, and that's certainly reason enough.

If I want to display via browser plugin or download a big document, whether formatted print or image or the combination of the two, djvu is the format of choice, if enough people can be persuaded to use it.

easiest to quote, I rearranged the text order a bit to highlight the most obvious and important difference.

From What's Inside DJVU

In short, DjVu is a multipage document format that can use a number of different coder/decoders (codecs) to compress the individual chunks that compose an images or a page. In fact, DjVu is really four compression techniques wrapped into one format:

BZZ: A general-purpose data compression technique similar to bzip2. Bzz is used to compress searchable text layers and other metadata in DjVu documents.

and that's what makes it more than just another compressed bitmap format like .JPG)

DjVuPhoto (aka IW44): A progressive, wavelet-based lossy compression format for continuous-tone images (i.e. photos and pictures).

DjVuBitonal (aka JB2): A lossless or lossy compression technique for bitonal (black & white) or palettized images that is particularly effective on images with repeated shapes (such as documents images where the same character appears many times in the document).

DjVuDocument: A technique for scanned color document that separates images into a foreground layer that contains the text and line drawings, and a background layer that contains the pictures and background textures. The foreground is encoded with DjVuBitonal and the Background with DjVuPhoto.

and that can really make for small files with big impact. I once downloaded a map document that was a meg or two with DJVU, that decompressed to 100+ megs when I decompressed it into a bitmap. (I think it was the early 1900s map of Yellowstone on the djvuzone site somewhere) The text was sharp and clear in either document... as you know, legible text does not survive high image compression levels well in ordinary bit maps.

What it is/does

Info from DJVUZONE:

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. . . . and white documents. Scanned pages at 300 DPI in full color can be compressed down to 30 to 100KB files from 25MB.. Black-and-white pages at 300 DPI typically occupy 5 to 30KB when compressed. This puts the size of high-quality scanned pages within the realm of an average HTML page (which is typically around 50KB).

How to get it

Viewers are available for Win/Mac/Linux.

The Linux package DJVUlibre allows both viewing and DJVU document creation and is Open Source. It is available for most major Linux distros, source, Solaris, cygwin and may be available for automated installation by whatever method your distro uses.

LizardTech (ABSOLUTELY NO RELATION) provides the free downloadable Mac/Win viewers, and sells Win/Mac DJVU creation tools. (either above URL)

However, there are also free document conversion sites, upload various file formats (e.g. PDF, images) and get back .DJVUs.

Check it out.

What it is/does

Info from DJVUZONE:

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. . . . and white documents. Scanned pages at 300 DPI in full color can be compressed down to 30 to 100KB files from 25MB.. Black-and-white pages at 300 DPI typically occupy 5 to 30KB when compressed. This puts the size of high-quality scanned pages within the realm of an average HTML page (which is typically around 50KB).

How to get it

Viewers are available for Win/Mac/Linux.

The Linux package DJVUlibre allows both viewing and DJVU document creation and is Open Source. It is available for most major Linux distros, source, Solaris, cygwin and may be available for automated installation by whatever method your distro uses.

LizardTech (ABSOLUTELY NO RELATION) provides the free downloadable Mac/Win viewers, and sells Win/Mac DJVU creation tools. (either above URL)

However, there are also free document conversion sites, upload various file formats (e.g. PDF, images) and get back .DJVUs.

Check it out.

What it is/does

Info from DJVUZONE:

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. . . . and white documents. Scanned pages at 300 DPI in full color can be compressed down to 30 to 100KB files from 25MB.. Black-and-white pages at 300 DPI typically occupy 5 to 30KB when compressed. This puts the size of high-quality scanned pages within the realm of an average HTML page (which is typically around 50KB).

How to get it

Viewers are available for Win/Mac/Linux.

The Linux package DJVUlibre allows both viewing and DJVU document creation and is Open Source. It is available for most major Linux distros, source, Solaris, cygwin and may be available for automated installation by whatever method your distro uses.

LizardTech (ABSOLUTELY NO RELATION) provides the free downloadable Mac/Win viewers, and sells Win/Mac DJVU creation tools. (either above URL)

However, there are also free document conversion sites, upload various file formats (e.g. PDF, images) and get back .DJVUs.

Check it out.

What it is/does

Info from DJVUZONE:

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. . . . and white documents. Scanned pages at 300 DPI in full color can be compressed down to 30 to 100KB files from 25MB.. Black-and-white pages at 300 DPI typically occupy 5 to 30KB when compressed. This puts the size of high-quality scanned pages within the realm of an average HTML page (which is typically around 50KB).

How to get it

Viewers are available for Win/Mac/Linux.

The Linux package DJVUlibre allows both viewing and DJVU document creation and is Open Source. It is available for most major Linux distros, source, Solaris, cygwin and may be available for automated installation by whatever method your distro uses.

LizardTech (ABSOLUTELY NO RELATION) provides the free downloadable Mac/Win viewers, and sells Win/Mac DJVU creation tools. (either above URL)

However, there are also free document conversion sites, upload various file formats (e.g. PDF, images) and get back .DJVUs.

Check it out.

http://djvuzone.org/djvu/att/archives/index.html.

Personal favorite: the invention of the transistor.

http://djvuzone.org/djvu/att/archives/index.html.

Personal favorite: the invention of the transistor.

"Auctioning the library off in such a piecemeal fashion just seems wrong, IMNSHO."

Whether that is wrong or not, I do think important historical documents should be electronically 'preserved' and made available for the benefit of the public. Some institutions and companies make an effort but not all and quality is variable - the British Library recently scanned some 17th century Shakespeare Quartos and put images of them up online in jpeg format. They are readable but not as readable as if they'd used something like the excellent DjVu.

It would be good to see documents like those original Turing and other papers preserved and presented like the Shannon example here has been - whatever later happens to the actual physical copies.

DjVu is a wavelet-based image compression format which gets about 50-70% better compression ratio than JPEG for a given level of image quality loss after compression.

The open-source DjVu decoder and encoder implementation is called DjVuLibre.

Interesting background information from www.djvuzone.org:

• After a 2 year hiatus, DjVuZone is coming back to life. DjVuZone is maintained by the original developers of DjVu Yann LeCun and Leon Bottou. Until recently, we had major disagrements with LizardTech's DjVu strategy. Seeing our creation go to waste because of corporate greed and incompetence was too much to bear. Rather than wasting our time trying to help LizardTech with their failed strategy, we decided to concentrate our efforts on maintaining DjVuLibre, the open source implementation of DjVu, and Any2DjVu, the free conversion server. Were it not for DjVuLibre, Any2DjVu, and a few dedicated fans of the technology (such as Jim Rile at PlanetDjVu), DjVu would have disappeared by now.

They have another imaging technology that they purchased from AT&T called DjVu. They've Open Sourced the viewer for that technology under the GPL.

I believe an encoder/decoder is also available under a GPL license, though LizardTech doesn't appear to be happy with the GPL because they are pro software patents, and the GPL is not. The encoder/decoder may or may not be a fractal engine, someone more knowledgeable will have to answer that question.

LizardTech may be involved in a squable over the JPEG2000 technology. Something to do with patent litigation.

= 9J =

The system isn't 800TB, but will scale to 800TB, according to this EDS press release. In fact, given that they've spent a mere $2.5M (powerpoint!) there's not a hope in hell that they've got 800TB! The powerpoint says it's a 5TB EMC SAN & an ADIC tape library for backup.

An interesting point is that they're delivering the documents using DjVu by Lizardtech, which is GPLd, and developed by the creators of DjVu in conjuction with LizardTech (after a period of LT not-getting-it). The DjVuLibre home page is here. LizardTech still have the best encoders for the format.

I'm using Firefox (from Windows sadly) and I can access the content just fine.

As for OSX and Linux users, there is a plug in for viewing the content needed. But they report to support OSX and "UNIX". The plug-in is called DjVu and has an open source equivalent at sourceforge (with RPMs, OS/2 and even Cygwin support).

I can think of two successors to JPEG...

JPEG 2000

JPEG 2000 is "the" successor to JPEG (designed by the same team), and was noticeably better than JPEG when I checked out quality vs size, but it's patent encumbered. It is however intended to be royalty and license-fee free.

Elysium Ltd has developed a freeware Netscape plugin to make IE, Opera and Netscape browsers able to view JPEG 2000 pictures. This plugin is for Windows, and I don't really know if there are others for other platforms.

DjVu

DjVu was designed for the web to replace common formats like JPEG, GIF and TIFF. Although designed primarly for compressing text, it's very efficient at regular photos as well, and should compress similarly as JPEG 2000 (about half the size of JPEG with similar quality).

DjVuLibre is a GPL licensed open source implementation that includes plugins, viewers, and encoders for this format.

I can think of two successors to JPEG...

JPEG 2000

JPEG 2000 is "the" successor to JPEG (designed by the same team), and was noticeably better than JPEG when I checked out quality vs size, but it's patent encumbered. It is however intended to be royalty and license-fee free.

Elysium Ltd has developed a freeware Netscape plugin to make IE, Opera and Netscape browsers able to view JPEG 2000 pictures. This plugin is for Windows, and I don't really know if there are others for other platforms.

DjVu

DjVu was designed for the web to replace common formats like JPEG, GIF and TIFF. Although designed primarly for compressing text, it's very efficient at regular photos as well, and should compress similarly as JPEG 2000 (about half the size of JPEG with similar quality).

DjVuLibre is a GPL licensed open source implementation that includes plugins, viewers, and encoders for this format.

The files are about 5 times smaller than with PDF for black and white 300dpi scans, and 10 or 20 times smaller for color scans (nothing even comes close to DjVu for high-res document scans).

DjVu is open source (the decoders and viewers at least). There are open source compressors, but they are not very good for scanned docs. You are better off using the free conversion server (see http://any2djvu.djvuzone.org ), or the commercial app from LizardTech (there is a free download version).

-- Anonycous Moward.

The files are about 5 times smaller than with PDF for black and white 300dpi scans, and 10 or 20 times smaller for color scans (nothing even comes close to DjVu for high-res document scans).

DjVu is open source (the decoders and viewers at least). There are open source compressors, but they are not very good for scanned docs. You are better off using the free conversion server (see http://any2djvu.djvuzone.org ), or the commercial app from LizardTech (there is a free download version).

-- Anonycous Moward.

Acrobat sucks ass for bitmap images. It doesn't display them very well, they don't print out well, and the files are huge. DjVu is a new image format that compresses extremely well (a few kilobytes a page -- actually comparable to ASCII text). It's somewhat proprietary, but it's probably the best solution here. There are free web-based services that can compress your images. You can try some of them and see for yourself.

http://www.djvuzone.org/

I've converted Keisler's calculus textbook to full text-searchable DjVu and put it up in both bundled (single file to download) and unbundled (many files for fast browsing) formats. Enjoy!

For those who don't yet know, DjVu is a free, highly effective compression format for scanned documents. Conversion from PDF to DjVu shrank the Keisler from 24MB to 10MB without perceptible loss in quality, and added incremental loading, fast browsing, and (most importantly) full-text search capabilities. Get the free viewer.

I've converted Keisler's calculus textbook to full text-searchable DjVu and put it up in both bundled (single file to download) and unbundled (many files for fast browsing) formats. Enjoy!

For those who don't yet know, DjVu is a free, highly effective compression format for scanned documents. Conversion from PDF to DjVu shrank the Keisler from 24MB to 10MB without perceptible loss in quality, and added incremental loading, fast browsing, and (most importantly) full-text search capabilities. Get the free viewer.

I've converted Keisler's calculus textbook to full text-searchable DjVu and put it up in both bundled (single file to download) and unbundled (many files for fast browsing) formats. Enjoy!

For those who don't yet know, DjVu is a free, highly effective compression format for scanned documents. Conversion from PDF to DjVu shrank the Keisler from 24MB to 10MB without perceptible loss in quality, and added incremental loading, fast browsing, and (most importantly) full-text search capabilities. Get the free viewer.

One of the main technologies behind DjVu is the ability to separate an image into a background layer (i.e., paper texture and pictures) and foreground layer (text and line drawings). Traditional image compression techniques are fine for simple photographs, but they drastically degrade sharp color transitions between adjacent highly contrasted areas - which is why they render type so poorly. By separating the text from the backgrounds, DjVu can keep the text at high resolution (thereby preserving the sharp edges and maximizing legibility), while at the same time compressing the backgrounds and pictures at lower resolution with a wavelet-based compression technique.

1. 
   Downloads faster.
   Displays and renders faster.
   Looks nicer on screen.
   Consumes less client resources.
   Can be OCRd and indexed.
   

You can't search a JPEG, but you can search a DjVu: you can run OCR and have the text embedded in the DjVu file. In fact, the on-line DjVu compression server does just that.

You could imagine having a clickable table of content. In fact, DjVu books that are done by hand have hyperlinked TOC (see DjVu Editions).

The best and cheapest way to get existing books on the web is to scan them and compress the images. Compression technology for text images is so good (see DjVu), and storage so cheap nowadays that you are better off just distributing high resolution scans.

This is a much more efficient way to make books available on the web, much more efficient than having volunteers painstakingly transcribe the text or correcting OCR mistakes.

OCR can be used for indexing scanned documents, but there is no need to do manual correction. DjVu can compress 300dpi black and white pages of text to 5-25KB. That's less than most HTML pages, and the images look just like the original book.

The Million Book Project at the Internet Archive uses DjVu (as well as other formats).

The open source implementation of DjVu is available on sourceforge

Here's my little blurb for a format that gets little attention, but would be of great benifit for everyone. It's even open-source.

DjVu

DjVu on the web

Plugins for various browsers

The size is considerably smaller than PDF with equal or better quality, and can be printed out.

They do need people to help with the libre version over at Sourceforge.

Here's my little blurb for a format that gets little attention, but would be of great benifit for everyone. It's even open-source.

DjVu

DjVu on the web

Plugins for various browsers

The size is considerably smaller than PDF with equal or better quality, and can be printed out.

They do need people to help with the libre version over at Sourceforge.

Here's my little blurb for a format that gets little attention, but would be of great benifit for everyone. It's even open-source.

DjVu

DjVu on the web

Plugins for various browsers

The size is considerably smaller than PDF with equal or better quality, and can be printed out.

They do need people to help with the libre version over at Sourceforge.

I will grant that PDF can store scanned documents, but it's really designed and best for storing printed-directly-to-PDF files...otherwise, you end up with absolutely massive files. Unfortunately, it's commonly used for said purpose. Even PNG would be much better.

DjVu is an interesting format that was primarily designed for storing scanned formats.

It uses a couple of techniques, such as OCR/pseudo-OCR, and multiple embedded images (JPEG/PNG) within the file for rasterable images. The idea is that, say, a scanned magazine page with text and a photographic image is stored as text, a little bit of outline font information, and a JPEG of the photographic image.

There is a free online conversion server at Any2DjVu.

Info can be found at DjVuZone.

There is a free online conversion server at Any2DjVu.

Info can be found at DjVuZone.

For scanned documents, nothing can beat DjVu. Bitonal documents are 3 to 10 times smaller than with TIFF or PNG. Color documents are 5 to 10 times smaller than JPEG or PDF. There is a free online conversion service at Any2DjVu.

... there's no problem with using an oddball format with only one implementation that has apparently been left to languish.

Well, they have an open-source project at sourceforge, and they provide utilities to convert to other formats.

While these constraints aren't an issue for folks attempting to document illuminated manuscripts and other like materials they are very much a problem for folks on the World Wide Web.

I agree, but it is useful for people like me who needed a scientific article which was offered only in DjVu format (conference proceedings, which is very difficult to find normally on the web, due to their large volume). Check CiteSeer (a database for research papers) for example, and the conference proceedings I mentioned was NIPS.

DjVu offers high rate of compression in the kind of documents you very well explained. Which is why it is useful for the people in the scientific community who is in need to communicate large volumes of research papers.

Let us know when you read another technology-of-the-future article from '98 though!

Gee, thanks.. That's a nice reply now. Whatever I've written was due to things I found out very recently, and somehow the DjVu web site is not down.

However you may be right in saying the format will disappear soon, this is not a valid reason to disregard this format when it can be useful for some of us.

I thought this has become common knowledge, but there's a bitmap compression format called DjVu invented at the AT&T Labs in 1998 which has significant advantages over the currently popular formats (JPEG, PDF, etc.). They advocate that their format is best suited for scanned documents.

• the files are smaller and display a whole lot faster.
• unlike PDF, it has no portability problems due to fonts, plug-ins, out-of-sync versions, encryption, etc..... Documents look exactly identical down to the pixel on every platform.
• it's perfect for scanned documents and photos (PDF does a terrible job at that)
• it is GPL'd , although the best compressors are commercial (like with MPEG).
• there are free conversion servers here, and here.
• the wiewer is 1.5MB (Acroread is 16MB).

Yeah, I'm biased, but still....

- AC

• the files are smaller and display a whole lot faster.
• unlike PDF, it has no portability problems due to fonts, plug-ins, out-of-sync versions, encryption, etc..... Documents look exactly identical down to the pixel on every platform.
• it's perfect for scanned documents and photos (PDF does a terrible job at that)
• it is GPL'd , although the best compressors are commercial (like with MPEG).
• there are free conversion servers here, and here.
• the wiewer is 1.5MB (Acroread is 16MB).

Yeah, I'm biased, but still....

- AC

Try DjVu. The files are smaller, and the reference library and the Unix netscape plug-in are GPLed.

Product info at www.djvu.com, Technical info and demos at djvuzone.org, and source code at sourceforge.net/projects/djvu.

I am one of the four persons who created DjVu in the first place. The events took place in AT&T-Labs Research between 1997 and 1999.

1. There is Linux support. Just go to the download page and select the Linux platform. Most of DjVu was first coded under Linux.
2. After the Lizardtech deal, we set up a "non commercial site" named DjVuZone. It contains general information, benchmarks. links, a searchable digital library, etc.
3. There is source code. Lizardtech recently had the good idea to relicense version 2 of the DjVu reference library under the GPL. We have the corresponding online documentation on DjVuZone. We are just waiting for the release of version 3 to redo that part of the site.
4. DjVu combines several new technologies including new approaches to arithmetic coding (Z'-coder), new compression methods for textual images (Soft pattern matching, JB2), new wavelet method (IW44), and new ways of combining them together. The current implementation is geared toward compressing scanned document images in 24 bit colors around 300 dpi (raw size is 25MB) and typically packs them into 50-60KB. Neither TIFF, nor JPEG, nor JPEG-2000 nor Fax-G4 can do that. None of these technologies will let you realistically view such documents over the web. DjVu can.

Hope this helps :-).

- Leon Bottou, AT&T-Labs Research.

I am one of the four persons who created DjVu in the first place. The events took place in AT&T-Labs Research between 1997 and 1999.

1. There is Linux support. Just go to the download page and select the Linux platform. Most of DjVu was first coded under Linux.
2. After the Lizardtech deal, we set up a "non commercial site" named DjVuZone. It contains general information, benchmarks. links, a searchable digital library, etc.
3. There is source code. Lizardtech recently had the good idea to relicense version 2 of the DjVu reference library under the GPL. We have the corresponding online documentation on DjVuZone. We are just waiting for the release of version 3 to redo that part of the site.
4. DjVu combines several new technologies including new approaches to arithmetic coding (Z'-coder), new compression methods for textual images (Soft pattern matching, JB2), new wavelet method (IW44), and new ways of combining them together. The current implementation is geared toward compressing scanned document images in 24 bit colors around 300 dpi (raw size is 25MB) and typically packs them into 50-60KB. Neither TIFF, nor JPEG, nor JPEG-2000 nor Fax-G4 can do that. None of these technologies will let you realistically view such documents over the web. DjVu can.

Hope this helps :-).

- Leon Bottou, AT&T-Labs Research.

I am one of the four persons who created DjVu in the first place. The events took place in AT&T-Labs Research between 1997 and 1999.

1. There is Linux support. Just go to the download page and select the Linux platform. Most of DjVu was first coded under Linux.
2. After the Lizardtech deal, we set up a "non commercial site" named DjVuZone. It contains general information, benchmarks. links, a searchable digital library, etc.
3. There is source code. Lizardtech recently had the good idea to relicense version 2 of the DjVu reference library under the GPL. We have the corresponding online documentation on DjVuZone. We are just waiting for the release of version 3 to redo that part of the site.
4. DjVu combines several new technologies including new approaches to arithmetic coding (Z'-coder), new compression methods for textual images (Soft pattern matching, JB2), new wavelet method (IW44), and new ways of combining them together. The current implementation is geared toward compressing scanned document images in 24 bit colors around 300 dpi (raw size is 25MB) and typically packs them into 50-60KB. Neither TIFF, nor JPEG, nor JPEG-2000 nor Fax-G4 can do that. None of these technologies will let you realistically view such documents over the web. DjVu can.

Hope this helps :-).

- Leon Bottou, AT&T-Labs Research.

I am one of the four persons who created DjVu in the first place. The events took place in AT&T-Labs Research between 1997 and 1999.

1. There is Linux support. Just go to the download page and select the Linux platform. Most of DjVu was first coded under Linux.
2. After the Lizardtech deal, we set up a "non commercial site" named DjVuZone. It contains general information, benchmarks. links, a searchable digital library, etc.
3. There is source code. Lizardtech recently had the good idea to relicense version 2 of the DjVu reference library under the GPL. We have the corresponding online documentation on DjVuZone. We are just waiting for the release of version 3 to redo that part of the site.
4. DjVu combines several new technologies including new approaches to arithmetic coding (Z'-coder), new compression methods for textual images (Soft pattern matching, JB2), new wavelet method (IW44), and new ways of combining them together. The current implementation is geared toward compressing scanned document images in 24 bit colors around 300 dpi (raw size is 25MB) and typically packs them into 50-60KB. Neither TIFF, nor JPEG, nor JPEG-2000 nor Fax-G4 can do that. None of these technologies will let you realistically view such documents over the web. DjVu can.

Hope this helps :-).

- Leon Bottou, AT&T-Labs Research.