03-09-2010, 04:29 AM | #1 |
Zealot
Posts: 111
Karma: 18638
Join Date: Dec 2009
Device: Sony DPT-S1, Kindle DX, iPad, Kobo Mini,H20,iRiver StoryHD
|
DJVU to ePub best results?
What methods have you used to convert DJVU to ePub?
The current method I am using is as follows: Open DJVU with DjVuLibre DjView 4.4 Export as PDF Then add PDF to Calibre Library and make ePub(this is basically running pdf2html utility) Problem is the conversion to PDF step. 4MB DJVU explodes to 35MB PDF! Then PDF to ePub goes down to 20-25MB, but the results are less than stellar. Slightly smaller problem is that running pdf2html on a 35MB PDF takes about a half an hour, but I could live with that if the quality was good. All of this was done on Ubuntu 9.10, but I would be interested in hearing about DJVU to ePub solutions on Windows or Mac as well. |
03-09-2010, 09:04 AM | #2 |
Wizard
Posts: 1,196
Karma: 1281258
Join Date: Sep 2009
Device: PRS-505
|
DjVu doesn't contain text, it works on images, and that's your problem. It uses an image-compression technology that's highly optimised for text and allows far smaller file sizes than other formats that target more general image types.
You could export the images and OCR them (lots of work to catch the errors), or you could try slapping the images all together as-is (which is what you describe above, possibly with some down-ressing to make it look even worse). Go back to the author and get a file that contains text, because DjVu is useless for your purpose. |
02-07-2011, 03:44 PM | #3 |
Junior Member
Posts: 5
Karma: 10
Join Date: Feb 2011
Device: Kobo Mini
|
I know nothing about this topic, but I have the same problem, and I note that DJVU files do seem to contain text - that is, the documents are searchable. They can be converted to non-searchable PDF with the print command (assuming you have a PDF print driver installed). But this significantly detracts from the utility of the files. And their size is a multiple of the original DJVU. There has got to be a better way.
|
02-07-2011, 04:16 PM | #4 | |
Guru
Posts: 691
Karma: 3026110
Join Date: Dec 2008
Location: Lancashire, U.K.
Device: BeBook 1, BeBook Pure, Kobo Glo, (and HD),Energy Sistem EReader Pro +
|
Quote:
For example most of the DJVU files on The Internet Archive (TIA) contain such a layer and I have used them as a basis for FB2 books. Of course the files the OP is working on may not have such a layer as the original text may not have been OCRd and associated with the image layer. BobC |
|
02-07-2011, 08:59 PM | #5 |
Booklegger
Posts: 1,801
Karma: 7999816
Join Date: Jun 2009
Location: Toronto, Ontario, Canada
Device: BeBook(1 & 2010), PEZ, PRS-505, Kobo BT, PRS-T1, Playbook, Kobo Touch
|
BobC - Can you tell us how to extract that hidden text layer? I haven't run across any DJVU books that I recall, but it would be good to know how to convert them when possible.
|
02-09-2011, 04:55 PM | #6 |
Guru
Posts: 691
Karma: 3026110
Join Date: Dec 2008
Location: Lancashire, U.K.
Device: BeBook 1, BeBook Pure, Kobo Glo, (and HD),Energy Sistem EReader Pro +
|
|
02-11-2011, 02:53 AM | #7 |
Zealot
Posts: 111
Karma: 18638
Join Date: Dec 2009
Device: Sony DPT-S1, Kindle DX, iPad, Kobo Mini,H20,iRiver StoryHD
|
OP here, I resorted to using export Text in WinDJView.
This gets you a text dump with no formatting whatsoever. For my Libre it works well enough, but in general, this procedure is suboptimal. Most DJVU files do seem to have a text layer (unless there is some on the fly OCR happening when you select an area on the page, which seems unlikely). Thus, there must be a way(at least theoretically until someone writes a converter) to preserve the formatting in the text layer. |
02-11-2011, 05:29 AM | #8 |
Banned
Posts: 2
Karma: 10
Join Date: Feb 2011
Device: Kindle 3 3G+WiFi
|
I just print from any djvu reader into a pdf printer, like primopdf or other... only thing is: 240 pages book, 4.5Mb originally was transformed into 40Mb... maybe trimming the quality of the pdf down...
|
02-12-2011, 10:04 AM | #9 | |
Guru
Posts: 691
Karma: 3026110
Join Date: Dec 2008
Location: Lancashire, U.K.
Device: BeBook 1, BeBook Pure, Kobo Glo, (and HD),Energy Sistem EReader Pro +
|
Quote:
If you want to understand DJVUs then you need to get the spec and study it. I've done quite a bit of work with adding TOCs to existing DJVUs and have converted a couple of books to FB2 - this involves manually proof-reading and correcting the dumped text then formatting it to match the original (italics, bold etc). Don't expect too much out of what is a by-product of the search function. BobC |
|
02-12-2011, 02:10 PM | #10 |
Grand Sorcerer
Posts: 11,470
Karma: 13095790
Join Date: Aug 2007
Location: Grass Valley, CA
Device: EB 1150, EZ Reader, Literati, iPad 2 & Air 2, iPhone 7
|
There is a description of DJVU in the wiki.
|
05-05-2017, 11:17 AM | #11 |
Banned
Posts: 23
Karma: 7476
Join Date: Feb 2013
Location: To the left of your body, to the right of your mind, lost in a riddle.
Device: Android phone, Nook Touch Simple Glowlight
|
OK, resurrecting an old thread, sorry. But, I'm now stuck with this problem, has conversion moved on since this was originally posted? I can extract the text in the djvu file (in a few different ways) but I can't get inline images to convert. What I want is to go from djvu to epub, I'm not worried about extra steps in-between as long as both text and images make it to the final epub. Like the OP I'm running Linux, but I can probably borrow a windows machine for a while if that's the only way to do this. Any ideas?
|
05-05-2017, 11:52 AM | #13 | |
Banned
Posts: 23
Karma: 7476
Join Date: Feb 2013
Location: To the left of your body, to the right of your mind, lost in a riddle.
Device: Android phone, Nook Touch Simple Glowlight
|
Quote:
|
|
05-05-2017, 01:41 PM | #14 | |
Grand Sorcerer
Posts: 5,582
Karma: 22735033
Join Date: Dec 2010
Device: Kindle PW2
|
Quote:
If your Nook is rooted, you might be able to install KOReader, which supports DJVU files. Alternatively, if the Nook PDF app doesn't have a reflow function, you might be able to use k2pdfopt to reformat PDF files generated from your DJVU files for your NOOK. (In case you can't figure out the optimal conversion settings, the author, willus, provides tech support in the k2pdfopt forum.) |
|
05-05-2017, 03:37 PM | #15 |
Banned
Posts: 23
Karma: 7476
Join Date: Feb 2013
Location: To the left of your body, to the right of your mind, lost in a riddle.
Device: Android phone, Nook Touch Simple Glowlight
|
|
Tags |
djvu epub conversion |
Thread Tools | Search this Thread |
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Qindle - Qt for Kindle (Now with PDF, DJVU, EPUB and CHM support) | meem | Kindle Developer's Corner | 14 | 07-21-2011 04:49 PM |
A real PDF to epub/djvu/rtf/html software?. | DsOft | ePub | 35 | 01-02-2011 03:57 PM |
Qindle .. Qt port with PDF, DJVU, EPUB and CHM support | meem | Kindle Developer's Corner | 17 | 10-03-2010 06:19 AM |
pdf to epub results in 'garbage'? | wulfie | Calibre | 6 | 09-23-2010 08:01 AM |
History Stillwell, Wendell. X-15 Research Results. Epub v1.0 12 July 2009 | Nate the great | ePub Books | 1 | 08-26-2009 12:02 AM |