Mangle

A couple of weeks ago I received an Amazon Kindle as a gift. I immediately began playing around with it and reading about certain undocumented features that the Kindle has. After a couple of hours I discovered it to be the perfect device for reading Manga. Manga is almost always grayscale, and the aspect ratio of most scanlations fits the Kindle's 600x800 pixel screen almost perfectly. Better yet, the Kindle's undocumented image viewer actually keeps track of the last image you viewed and thus you are always able to return to the page you left off on when you power on your Kindle. The device supports several popular image formats (jpeg, png, gif, etc), and is able to dither and downscale images to fit the screen.

However... The Kindle's image viewer does have certain shortcomings:

The Kindle is very picky about file format; any additional embedded data (thumbnails, comments, possibly even exif data) can confuse it. As a result, images may not display properly or even not at all (which actually prevents you from reading the given book, as one bad panel will prevent you from viewing subsequent images).
The first image that you view in a manga (until the Kindle first writes the "bookmark" file) seems to be arbitrary even when files are named sequentially. About half the time it will correctly pick the first file in the batch, at other times it will pick out some other image seemingly at random.
Normally for Kindle to find your manga scans you have to press Alt+Z on the home screen. I haven't always had luck with it correctly identifying image directories. At other times, after finding an image directory the Kindle will appear to hang while trying to access it (forcing you to return to the home screen).
The Kindle image viewer has no functionality to rotate images. So if there is a horizontally large image (such as what often happens with dual-page scans), it can be difficult to make out the text because the image is simply scaled to fit (consequently leaving a lot of wasted space at the bottom of the screen).
Scanlation images are oftentimes much larger than the 600x800 screen; not only does this make them take more space on your memory card but it also slows down image loading (the Kindle has to read more data off of the slow SD card and scale the image). Scanlations often also include color scans of covers and inserts which take up more space than a grayscale equivalent (which is would be fine for the Kindle's limited display).
Kindle's image viewer provides no way to sort images (to determine in which order they are shown). This can be very problematic especially considering that scanlation groups have differing naming conventions, and as a result files from later chapters may appear before earlier ones when you are reading your manga (spoilers ftl).

I was annoyed with these issues and thus Mangle was born (the program name is a mix of "Manga" and "Kindle" in case you haven't figured it out yet; I thought it was pretty clever at the time). Fortunately you can get all the benefits of my work without really doing anything (and it won't even cost you anything since Mangle is free, GPL software). With Mangle you can easily:

Sort and organize images from different directories; bulk rename feature for output to the Kindle
Optionally re-save images in a format Kindle will be sure to understand with no visible quality loss
Downsample and rotate images for optimal viewing on Kindle, convert to grayscale to save space and improve contrast
Automatically generate book meta-data so that your manga is always properly detected and viewable in-order

Mangle is also cross platform, and doesn't require an install (it's a standalone executable that you can run from anywhere). It is also "environmentally friendly" by not messing with your registry or modifying your system in any way. If you ever want to uninstall it, just delete the executable and you're done.

Usage Instructions

Mangle is pretty easy to use, so this won't be really in-depth. If you have any questions drop me a line though.

Add images to the current book by selecting the "Book | Add | Files" or "Book | Add | Directory" menu items
If certain images are not in the order you want, select them in the window, and select the "Book | Shift | Up" or "Book | Shift | Down" menu items
Configure the book title and image processing options by selecting "Book | Options"; this will be the title you see in the Kindle home menu
Create a root-level directory on your SD memory card/Kindle called "pictures" (case might matter)
Once you are satisfied with the your images and options select "Book | Export" and select the "pictures" directory you just created
After the export is complete your new manga books will show up along with all your other books (if they don't for some reason, press Alt+Z while on the home menu)

The Kindle 2 Image Viewer Bug

I've received a couple of reports (and found similar stories on the web) about an annoying bug some owners of Kindle 2 are experiencing. Apparently under certain conditions the Kindle 2 image viewer (which Mangle leverages) will not properly update the display when you flip between picture pages. If this starts happening to your Kindle 2 then you can fix it by performing a reset (holding power button down for 15 seconds). This problem is described in more detail in this forum thread. I don't own a Kindle 2 myself but have used one for viewing manga before with no problem; maybe this notice will be of help to those who run into this issue.

A Disclaimer...

You probably know how this goes by now... Mess around with your Kindle at your own risk. Honestly, nothing bad is going to happen; however if something does then it's your problem.

Downloads (Version 1.1; 2/28/2009)

The Windows binaries and source code for the latest version of Mangle can be found below. You can also download older versions if you like.

Mangle Executable - binary release for Windows users (Win2k and later)
Mangle Executable (Preview) - temporary one-off build by Chris for Kindle 2 DX resolution support
Mangle Source - C++ source code for building on other OSes (and for developers)

Building on Linux

Mangle was initially developed on Xubuntu 8.10 and it's really simple to set up a build environment. If you are running an *buntu variant (although this will probably also work with all Debian based distributions), install the following packages (using apt-get):

build-essential
libwxgtk2.8-dev
libgraphicsmagick1-dev
libmagick9-dev

After you install these packages, simply open up a console to where you extracted the Mangle source code and type make CFG=RELEASE, and you're done (the executable will be created in the ./bin/Release directory)! If you run into any problems building Mangle don't hesitate to ask.