DJVU, anychance?

Artha · 07-30-2011, 08:37 AM

I have a few djvu files. From what I read online, it's a breeze to work with them compared with PDFs from a programmer's standpoint. Is there a chance to have them supported just like PDFs? Meaning reading the metadata, extracting the cover, etc.

itimpi · 07-30-2011, 09:01 AM

Up to now none of the developers has felt motivated enough to create a Calibre plugin that supports DJVU. I do not think there is anyoen against such support - just no one willing to do the work required.

Manichean · 07-30-2011, 11:02 AM

From what I know, DJVU would be about as useful as an ebook format as PDF, but I'm pretty sure that Kovid would include a plugin if someone were to write and support one.

Caleb666 · 08-04-2011, 05:56 AM

DjVu is particularly useful for textbooks. I have many textbooks in that format, and it would've been lovely to see it supported for the same reason PDF is.

DoctorOhh · 08-04-2011, 07:33 AM

Quote:

Originally Posted by Caleb666

DjVu is particularly useful for textbooks. I have many textbooks in that format, and it would've been lovely to see it supported for the same reason PDF is.

PDF is supported for the 1000s of basic novels floating around in that format. You won't find many text books in PDF that can be successfully converted to ePub or Mobi and still be very usable.

As had been stated in the past if someone comes along that has an interest in this format and the skills I'm sure Kovid would welcome a patch.

Caleb666 · 08-04-2011, 09:17 AM

Yes, I know, but I'm using an iPad, not an ebook reader, so I can read scanned books (e.g. older math or science textbooks) easily on it.

From what I see, I can add DJVU files to my library, and I can edit metadata too... so it seems that Calibre does support DjVu files after all.

chaley · 08-04-2011, 09:50 AM

Quote:

Originally Posted by Caleb666

From what I see, I can add DJVU files to my library, and I can edit metadata too... so it seems that Calibre does support DjVu files after all.

In that sense, calibre supports any extension. You can drop anything into the format box.

What you cannot do is examine metadata in the file, update metadata in the file during save/send, or view it with calibre's viewer. These operations require that code be written that understands the internals of the format.

Caleb666 · 08-04-2011, 01:01 PM

You are talking about modifying the files itself... but doesn't Calibre write metadata in a separate OPF file (and the database), or does it actually modify some file formats (like EPUB and MOBI?).

In the case of file formats it doesn't understand, I still can edit and update metadata, it just doesn't get saved in the file itself, right?

user_none · 08-04-2011, 01:07 PM

Calibre writes metadata changes to its database file. It also writes an opf file with the metadata to disk as a backup. Formats that have a metadata writing plugin installed will have the metadata written to the file itself when it is written outside of calibre (save to disk, send to device ...).

chaley · 08-04-2011, 01:07 PM

Quote:

Originally Posted by Caleb666

You are talking about modifying the files itself... but doesn't Calibre write metadata in a separate OPF file (and the database), or does it actually modify some file formats (like EPUB and MOBI?).

Calibre can modify the metadata in many formats. It does this during save-to-disk and send-to-device. It does not modify metadata in the formats stored in the library unless you do a convert.

The OPF file is a backup of the metadata stored in calibre's database. Calibre reads this file only when restoring the database.

Quote:

In the case of file formats it doesn't understand, I still can edit and update metadata, it just doesn't get saved in the file itself, right?

Yes.

07-30-2011, 08:37 AM	#1
Artha ----- Posts: 114 Karma: 10 Join Date: Jun 2011 Device: Samsung SNE65	DJVU, anychance? I have a few djvu files. From what I read online, it's a breeze to work with them compared with PDFs from a programmer's standpoint. Is there a chance to have them supported just like PDFs? Meaning reading the metadata, extracting the cover, etc.

08-04-2011, 09:17 AM	#6
Caleb666 Zealot Posts: 100 Karma: 400000 Join Date: Jul 2010 Device: iPad 2 64GB	Yes, I know, but I'm using an iPad, not an ebook reader, so I can read scanned books (e.g. older math or science textbooks) easily on it. From what I see, I can add DJVU files to my library, and I can edit metadata too... so it seems that Calibre does support DjVu files after all. Last edited by Caleb666; 08-04-2011 at 09:32 AM.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
DJVU Problem	LTCSZ	Conversion	2	02-04-2011 09:24 PM
iLiad My djvu viewer	ericshliao	iRex Developer's Corner	8	10-17-2010 08:28 AM
djvu	ulgr	Calibre	4	07-09-2010 05:25 AM
Easy DJVU Reader - reading DJVU books	Rsfor	Apple Devices	5	02-05-2010 08:30 PM
DJVU?	algol	iRex	5	06-09-2009 06:28 AM

07-30-2011, 09:01 AM	#2
itimpi Wizard Posts: 4,553 Karma: 950151 Join Date: Nov 2008 Device: Sony PRS-950, iphone/ipad (Marvin/iBooks/QuickReader)	Up to now none of the developers has felt motivated enough to create a Calibre plugin that supports DJVU. I do not think there is anyoen against such support - just no one willing to do the work required.

07-30-2011, 11:02 AM	#3
Manichean Wizard Posts: 3,130 Karma: 91256 Join Date: Feb 2008 Location: Germany Device: Cybook Gen3	From what I know, DJVU would be about as useful as an ebook format as PDF, but I'm pretty sure that Kovid would include a plugin if someone were to write and support one.

08-04-2011, 05:56 AM	#4
Caleb666 Zealot Posts: 100 Karma: 400000 Join Date: Jul 2010 Device: iPad 2 64GB	DjVu is particularly useful for textbooks. I have many textbooks in that format, and it would've been lovely to see it supported for the same reason PDF is.

08-04-2011, 01:01 PM	#8
Caleb666 Zealot Posts: 100 Karma: 400000 Join Date: Jul 2010 Device: iPad 2 64GB	You are talking about modifying the files itself... but doesn't Calibre write metadata in a separate OPF file (and the database), or does it actually modify some file formats (like EPUB and MOBI?). In the case of file formats it doesn't understand, I still can edit and update metadata, it just doesn't get saved in the file itself, right?

08-04-2011, 01:07 PM	#9
user_none Sigil & calibre developer Posts: 2,487 Karma: 1063785 Join Date: Jan 2009 Location: Florida, USA Device: Nook STR	Calibre writes metadata changes to its database file. It also writes an opf file with the metadata to disk as a backup. Formats that have a metadata writing plugin installed will have the metadata written to the file itself when it is written outside of calibre (save to disk, send to device ...).

Advert

Advert