Talk:DjVu/Archive 1

formatted PDF document
''*The DjVu media format cannot store formatted text. It just stores all the data in plain text and the text components are tagged to specific areas.''

PDF can store formatted text. But it cannot be converted in easy way to source document. Moreover, text from many PDF documents cannot be even copied to clipboard! Many times in order to preserve formatting PDF document must be OCRed just like DJVU!

Only minor text edits can be done using expensive Adobe software and if document contains any tables, it is not possible to modify it in an acceptable way. It is not possible to preserve formatted text using clipboard. So in my opinion it is not PDF adventage over DJVU.

- Sorry, I was wrong. PDF file IS editable, with help from third-party software vendors (at least), like Foxit.


 * PDF is an open standard (even if it was defined by Adobe). All you said are problems with the Adobe reader, not with the format. A correctly created PDF file (from original .tex source with .eps images) will always be editable, selectable, printable in arbitrary resolution, and will have a smaller file size than a DjVu for the same situation. 143.106.18.169 16:49, 14 February 2007 (UTC)

conversion between djvu and pdf
Are there any tools for converting djvu files to PDF format? 217.132.202.109 15:27, 20 July 2007 (UTC)

PDF printing software could do the job 69.156.175.57 16:55, 31 October 2007 (UTC)

IrfanView + Djvu/PDF plugins is another option. --84.78.178.21 (talk) 22:32, 4 March 2008 (UTC)

--

on djvu vs pdf
I posted this in the comment section as, first, I didnt check any of the following which derive formely from my use of the two format. And, furthermore my english is pretty limited so I hope someone can check those fact and correct my english mistake and published it in the main article if it feels needed.

The passage on djvu vs pdf is very confuse. Distinction must be made between TEXT, IMAGE and COMBINE MODE data. As mode of compression TEXT offer the best performance (while requiring thorough proofreading to ensure conversion process from OCR). For IMAGE many compression format are available, of which DjVu reach the top in his line. The one I call COMBINE MODE is where TEXT data (which are gather from a quite rought OCR) are held under the IMAGE data to allow search, copy, and so on (of our imperfect TEXT data). It is for obvious reason the most heavier of the three. We may now compare our two format throught these category. Actually PDF do support both TEXT or IMAGE separately or in COMBINE MODE which difference will determine the size of the file at the end. His IMAGE data are stored using jpeg compression which is less efficient then DjVu. Compare to a doc or txt format TEXT data in PDF are more difficult to edit and more tied to their page layout. DjVu format is not intend to store and display TEXT data but IMAGE data(though it support COMBINE MODE).

We could say that PDF is more of a container where DjVu is a compression format. Hence the theorical possibility of having PDF with image compress in DjVu

Wouldn't it be better to have a separate more general article called for instance "prints to digital" to explain these ?

On resizing

Resizing without making pixel visible depends on which kind of data you have IMAGE, TEXT or VECTOR, the later two allowing scaling without the former flaws. So it more depends on the kind of data you have at first then with the PDF or DjVu format (though DjVu only support the IMAGE data while PDF support TEXT, IMAGE and VECTOR) 69.156.175.57 16:55, 31 October 2007 (UTC)

—Preceding unsigned comment added by 69.156.175.57 (talk) 16:12, 31 October 2007 (UTC)

Decompressing DJVU
This article seemingly contains a lot of useless information, except what most people would require: information on how to decompress a DJVU format file. —Preceding unsigned comment added by 24.185.1.129 (talk) 15:07, 4 August 2008 (UTC)

PDF Comparison section should be removed
Is this an article on the DjVu format or just a semi-biased PDF-DjVu comparison? The article should focus on what DjVu is (a format primarily designed for *scanned* documents, so the comparison with vector formats is useless) and where it's being used, instead of discussing in great detail why PDF is or is not better than DjVu. I think I'm going to go ahead and just remove that section ... If it's considered valuable information, I think it's better placed in a separate article anyway, and not in DjVu or PDF. —Preceding unsigned comment added by 129.177.44.106 (talk) 09:22, 18 October 2008 (UTC)


 * I'm not sure what you're talking about. The only part of the article that describes the differences between DjVu and PDF is as follows:
 * "DjVu has been promoted as an alternative to PDF, as it gives smaller files than PDF for most scanned documents."
 * That's hardly great detail, and even hardlier the majority of the article. 129.15.131.245 (talk) 09:30, 19 October 2008 (UTC)
 * That's most likely because by the time you've seen the article, the comparison section has already been removed. —Preceding unsigned comment added by 129.177.44.71 (talk) 14:39, 10 November 2008 (UTC)

intent of this sentence
I'm not sure what the intent of this sentence is: Once a PDF has been converted to DjVu, it becomes as good as an image and a text file bound together.  "As good as" by what criteria? "Bound"? Maybe an example or rewording is in order, but I don't know what this is trying to express. --Ds13 15:13, 28 September 2006 (UTC)

Free Vs. Open Formats
In the body of the article is the claim: "DjVu is a free file format". The citation listed for this claim only specifies that djvu is an open standard. An open standard is not the same as a free standard. For example, from Free and open source software, we have, Free software licences and open source licenses are used by many software packages. The licenses have important differences, which mirror the differences in the ways the two kinds of software can be used and distributed and reflect differences in the philosophy behind the two.

In light of the differences between open and free, it is potentially misleading to call djvu a free format. Someone who knows more about djvu than me should provide a clearer citation for the claim regarding freedom, or else change the wording to reflect the fact djvu is open but not free.128.250.45.36 (talk) 02:28, 16 March 2010 (UTC)

not an open file format
According to http://djvu.sourceforge.net/licensing.html and http://djvu.sourceforge.net/lti-licensing.html is not an open file format because it is patent encumbered and cannot be used by anybody without royalties. (This violated the definition given in the Wikipedia article of open file format and 3. of the definition of Open Standards that is used by the FSFE.

Breiter (talk) 12:33, 30 April 2010 (UTC)

(Media Type)
Posts indicate MIME type image/vnd.djvu may have less or no support. What is the source stating it is valid? Eshouthe (talk) 16:33, 2 August 2010 (UTC)


 * 1. http://www.iana.org/assignments/media-types/image/vnd-djvu
 * 2. if image/x-djvu is a provisional tag as I suspect, the browser vendors are slow as usual...
 * Rursus dixit. ( m bork3 !) 12:49, 11 September 2010 (UTC)

Unjustified comparison
The comparison with PDF seems to be unjustified: DjVu seems like a raster image format (in principle), while PDF is packed Encapsulated PostScript, which is a vector format. Also: there is no immediate conversion from image files to PDF, PDF is generally direct generated from various desktop publishing software, while DjVu, as I perceive it is a kind of OCR encoding, that has to store images as raster images. Rursus dixit. ( m bork3 !) 12:59, 11 September 2010 (UTC)

NPOV dispute
The section History is just so ridiculously anti-PDF, attributing "aggressively marketed" to PDF, giving DjVu the innocent victim role. They're image formats for God's sake, not persons with glittering eyes and sneering mouths! We don't care if the "evil" PDF swallows DjVu whole, we're not going to feel pity for it unless it has a practical usage that it does better than PDF. Rursus dixit. ( m bork3 !) 14:04, 11 September 2010 (UTC)


 * Okay, so change it! — Fly by Night  ( talk )  19:50, 11 September 2010 (UTC)

Not neutral
In my opinion the content is not neutral. It tries to push the idea that Djvu format is superior than PDF without much proof except format author's claims. It also assumes that PDF format is equivalent to Djvu which I doubt. There are lots of possibilities in PDF apart from just images. It is also possible to encode images in pieces, it only depends on a file producer. PDF can also use other compressions than JPEG. There are also seem to be unsupported claims that PDF is more common due to advertizing and nothing else. There is no proof for those words too. Nobody probably made any marketing research of this (to proof anything). It would be great to see it more neutral. --Mrd000 (talk) 21:15, 22 September 2010 (UTC)

Color coding of release history
People with Color_blindness may have problems recognizing the different colors. I propose to change the table to have one more column that displays the state of the release in textual form. --Dreiraumzimmer (talk) 13:53, 24 November 2010 (UTC)

Actual use
The impression I get is that despite this articles big talk "widely used across economic sectors" and despite the formats technical advantages for scanned documents this is still a pretty rare format. Pretty much every academic or technical document I come across is a PDF. Plugwash (talk) 23:17, 12 April 2011 (UTC)