OK. Now that the iLiad supports Mobipocket content, I decided to look further into the format.

Previously, I eschewed the format because:
1. It's proprietary (only readable by Mobipocket).
2. It's not reversible - any eBook distributed in Mobipocket cannot be converted into something else.

Overall, the Mobipocket reader is 1 step forward from the PDF viewer - mainly because it supports reflowing content. But that's only reading.

I want to create my own content.

The Mobipocket web site is of limited use for this. The final instruction for creating content is always "use our proprietary software that only runs on buggy, insecure, overpriced Microsoft products" to create the eBook.

Now, I've successfully created Mobipocket content by putting an HTML file into a PalmDOC container. (Note that the Mobipocket reader will not read text files in a PalmDOC container.) Such Mobipocket eBooks are reversible. But have a drawback: only 1 file can be in the container. So no graphics, etc. Just the single document.

I've examined the .mobi files that came with the reader and the Open eBook Format documentation. The problem is that instead of using the standard ZIP container, Mobipocket opted for the file system container. They offer no documentation on this container and the file system they are using does not conform to any known file system.

So it looks like that the Mobipocket format also takes 1 step backwards: I cannot create the same rich content that I can using PDF.

My testing is by no means complete, but right now I don't see anything that has proven my original thoughts of the Mobipocket format wrong.

Mobipocket eBooks are proprietary.
Mobipocket eBooks (that are not an HTML/PalmDOC files) are not reversible.

I agree that Mobipocket is a proprietary format and cannot be converted into something else. That's why I always save my original master copies in HTML format when making a .prc file.

I have been saving my master copies for years, ever since my first eBookwise reader with its proprietary .imp format.
I used these master copies to make .pdf files -- another proprietary format -- when I eventually changed to the iLiad.

Not everyone is able to or desires to convert their own content. For these the the Mobipocket viewer is a wonderful addition to the iLiad. I think it increases the value of the iLiad and will make it more appealing to buyers because they now have a much larger choice of content. Some readers do wish to purchase DRM'd ebooks and for these the viewer is a great thing to have. I am personally opposed to DRM but I have to be realistic and live in today's commercialistic world. If we want the iLiad to be a marketing success, it will help if it can accommodate secure and non-secure content.

MobiPocket seems to be one of the better "closed" formats. From their web site: mobigen (formerly known as prcgen): this command line tool allows you to build a Mobipocket eBook from an OPF publication or a single HTML file. One hangup is that mobigen, like Mobipocket Creator, only works on Windows. There have been requests for a Unix/Linux version on their forum (http://www.mobipocket.com/forum/viewtopic.php?t=5122) and Mobipockets response was encouraging, but the bottom line is that there is no non-Windows mobigen yet. Another hangup is that there needs to be a mobi2opf command to go back to a non-proprietary format. I think it would be to MobiPocket's advantage to make available source-code for both opf2mobi (mobigen) and mobi2opf. Note that these would obviously be without encription, and would have the effect of making many more books available in the MobiPocket format. I think MobiPocket should do this, but I won't be holding my breath. It should not be all that difficult to produce versions without MobiPocket's support. For example, FBReader already reads unencripted Mobi files, so mobi's file format wrapper to opf is either discoverable or actually documented somewhere.

MobiPocket's Forum includes a thread (http://www.mobipocket.com/forum/viewtopic.php?t=3193) on using mobigen under wine. It was reported to work, although the old prcgen was easier to get going.

The Mobipocket web site is of limited use for this. The final instruction for creating content is always "use our proprietary software that only runs on buggy, insecure, overpriced Microsoft products" to create the eBook.


I take it that you dont like Windows...at all ;)


So it looks like that the Mobipocket format also takes 1 step backwards: I cannot create the same rich content that I can using PDF.

By no means, the Mobipocket is not the holy grail of formats. It is a format developed by a company with a specific purpose in mind (books). It is not an 'universal' format like PDF is, so as long as the format does what it's creators want it to do, there is no reason for the company to change/improve it.

The Mobipocket source is OeB format so it is XHTML. The content of the book is slightly altered to suit the needs of the Reader program. Mainly the image tags are changed to contain a number attribute and the anchor tags to contain an attribute giving the file offset to the anchor destination.
The .prc file can be compressed in several ways. Standard Palm compression which is documented. Such books can be reverted to source. Usually the books are compressed in the proprietary Mobipocket compression.
The DRM is probably simply an encryption using the PID as key.
The current .mobi format is only different in some details.

Do not be too harsh with Mobipocket. They are working on a mobigen for Linux program. Their main problem seems to be lack of specialist programmers.