DjVu viewer with full zoom and panning around the page

[tigran]

I have written a DjVu viewer for Hanlin V3 (aka "BeBook 1" or "Pixelar" or "Lbook V3" depending on where you live). I called it libdjvu to match the name of the plugin "libdjvu.so". It is written in C and uses GPL'd djvulibre library.

The main features are: arbitrary level zoom (down to microscopic level, so you can examine individual dust specks present while the book was scanned and panning the view window around the page.

Note that this means that not only all scanned books (literally _millions_ of them!) are now available for reading on Hanlin V3 but also any "nasty" PDF (i.e. those which can't be handled by Adobe reader properly) can be very easily converted to DjVu (via pdftoppm, cjb2 and djvm) and handled by this viewer.

The source code (GPL) and both the arm and i386 binaries are here:

http://www.bibles.org.uk/libdjvu-1.1.tar.gz

but most of you are probably more interested in a ready-made firmware image containing it. So here it is as well (based on the latest lbook one but you can easily set the language to English if you don't like Russian as default):

http://www.bibles.org.uk/hanlin-v3-firmware.zip

To use it just open any .djvu file as usual and use the following keys:

ZOOM IN/OUT: Volume '+'/'-' keys
There are menu options for increasing/decreasing the zoom step.

ZOOM RESET TO DEFAULT (i.e. FIT WIDTH): Long press volume '+' key

PAN AROUND THE PAGE: Next/Prev buttons (on the left side) for vertical and long presses of these for horizontal movement.
There are menu options for increasing/decreasing the horizontal and vertical movement steps.

ROTATE: Long press 'OK' to toggle between Landscape and Portrait modes. Note that rotating resets the zoom level to default zoom state.

TOGGLE BETWEEN COLOUR AND B&W MODES: Long press volume '-' key.
(colour mode is important for many Google Books and archive.org djvu files because they sometimes split the text between different layers. I personally always convert important stuff to pure bitonal format but not everyone is willing to spend time or knows how to do it, so I implemented this toggle).

Try "About..." menu option to see various bits of info, current zoom level, step values, current rendering mode etc.

Comments, bugreports etc etc => tigran@bibles.org.uk.

[keng2000]

Very nice library...
I will try it.

[tigran]

I fixed a couple of bugs pointed out by folks at the-ebook.org and uploaded the current stable version to the following location:

http://www.bibles.org.uk/libdjvu

Note that I have now started adding some advanced features and optimizations so it will be a long while (more than two days before I make the next version available, i.e. call it "stable".

[Siorghlas]

I find your work very interesting and useful. Have you thought of integrating it with OpenInkpot? That would be a good marriage.

[mbovenka]

Originally Posted by Siorghlas

I find your work very interesting and useful. Have you thought of integrating it with OpenInkpot? That would be a good marriage.

I was thinking the same thing.

[tigran]

Originally Posted by Siorghlas

I find your work very interesting and useful. Have you thought of integrating it with OpenInkpot? That would be a good marriage.

Thank you, I will consider it. But first I need to complete the current version and make sure it is as efficient and stable as possible.

[allen]

Originally Posted by tigran

Thank you, I will consider it. But first I need to complete the current version and make sure it is as efficient and stable as possible.

Tigran! Good Job! Mr Aivazian

[sankar10]

This might be the best news for people likeme who have lots of badly scanned pdf books and would like to use hanlin to read them , if only they knew how.

[Siorghlas]

Tigran, I wonder what firmware version from which manufacturer have you used in the integrated version you have for download. And related to it, I'd like to know if it would be difficult to integrate the library with newer firmwares. If I were to do it myself with my preferred firmware, would I have to recompile the firmware? How would I do it?

[tigran]

I have just released the final stable version 1.3 of libdjvu:

http://www.bibles.org.uk/libdjvu/

As for the base firmware --- I used the latest lbook.ua one plus I made some modifications to speed up startup, speed up update (removed unused programs, e.g. screen calibration is not needed for Hanlin V3 which has no touchscreen), fixed some spelling/grammar errors in both English and Russia menus etc etc.

If you want to use libdjvu.so in another firmware you have to copy arm-lib/libdjvu.so to wherever the libraries are stored in your version. In mine it is in /usr/lib of rootfs cramfs image. Also, to be on the safe side, copy the libdjvulibre* files (and symlinks) from my image as these I compiled myself and tested whereas some others may or may not work with my libdjvu.so.

[tigran]

I released the version 1.6 which has Spanish localization plus some more optimizations and an extra feature (you have to turn it on via menu option) to show previous window position via horizontal line --- this helps the eye to quickly locate the next line to read when panning the window vertically.

[Siorghlas]

Wow, I'd just downloaded v1.5 a couple of hours ago! Keep up the good work!

[tigran]

I moved the project to SourceForge.net:

http://sourceforge.net/projects/libdjvu/

[avysk]

Is it possible to have your viewer as separate thing running from SD card, instead of reflashing the device?

[tigran]

Originally Posted by avysk

Is it possible to have your viewer as separate thing running from SD card, instead of reflashing the device?

Unfortunately, not. The reason is because the paths to plugins are hardcoded in Jinke's viewer software so they cannot be changed. However, what you can do (if you want to use the rest of your firmware and only replace the DjVu support) is to take libdjvu.so and libdjvulibre.so* files from my V3update.bin and put them in rootfs/usr/lib of your V3update.bin firmware image.

Today I have released libdjvu 1.8 which has support for multicolumn mode of window movements. This is useful for reading books typeset in two (or more) columns, e.g. encyclopedias.