I’ve talked to a few authors and editors who wish to create custom templates for iBooks Author, well beyond what is possible making minor changes to fonts.
To create a custom template with altered background images and formatting, first create a simple iBook using an existing template.
If you are familiar with the ePub format, which is a compressed directory, you know there are several folders within the ePub. These folders contain what might be compared to a self-contained website. I like the ePub structure and wish iBooks were closer to that format than they are. But, Apple goes its own way. The iBooks format is much simpler than ePubs.
Do you wonder what is inside an iBooks “iba” file? To find out, do the following:
1. Copy your “.iba” (I use the Apple-D “Duplicate” command in Finder)
2. Change the extension from “.iba” to “.zip”
3. Double-click the “.zip” file, which will uncompress the folder
4. Explore the new folder
First, you will notice there are a lot of files. In the iBook I tested for this analysis, there were 16,720 files and one folder. That’s why I suggest using a nearly empty book to craft a custom template.
The entire text of the book, layout information, and revision data reside in two files:
The “index.xml” can be opened in any text editor. If you open this file, you can skim through the file until you see the text of your book. While the ePub format supports chapters or sections as individual files, the Apple approach places everything in one huge XML file. Again, I prefer the ePub standard instead of placing everything in one disorganized folder.
The only subdirectory / folder that Apple creates in the iBooks format is named “QuickLook.” The folder contains thumbnail images of the book. This is interesting because the mail folder also contains a long list of thumbnail images. In the sample book I am using for this analysis, the thumbnails in the main folder are named KFPageThumbnail-XXX.jpeg, where the XXX ranges from 1 to 650.
In the example books I have explored, there are some images that seem to exist no matter what. These image files are:
I don’t know what the purpose of the “slate” set of images might be, but they appear in three different books I created using a mix of templates. Maybe someone else can dig into these?
There are also several other image files. These seem to be the images used for the various templates, based on my explorations. These files are different in each template. The design files in the book used for this example are:
Three Adobe/Apple color profiles are also in the book folder:
If you want to craft a custom template, you need to alter the files in this uncompressed iBook folder. For example, you could change the “Background-1.jpg” to a background of your own design. Match the size of the existing file, though. Don’t worry about things like “DPI” or other settings in a graphics program: focus on the pixel-by-pixel size, such as 1024-by-768 pixels used by the original iPad screens.
Once you have changed images or made other tweaks, you can then compress the file back into a “.zip” format. Changing “.zip” to “.iba” makes the compressed folder an “iBook” again, a document you can open and edit in iBooks Author.
Again, the steps are:
1. Create an “empty” shell book using an existing template.
2. Duplicate the file and change the extension to “.zip” so it can be decompressed.
3. Decompress the iBook into a folder you can edit.
4. Alter or replace any images you wish to customize.
5. Compress the modified folder.
6. Change the extension from “.zip” back to “.iba” to open the file in iBooks Author.
7. Open the new file in iBooks Author and save it as a template!
You now have a customized template.
For a discussion on creating a template, read the following thread in the Apple Discussion Forums: