Dual display format Kindle file

[PaulFraser]

I currently get a magazine in my iPad Kindle app that provides two different modes of display. One is a standard Kindle ebook format similar to that which displays on my original Kindle; the other offers a PDF/image-like copy of the actual magazine page. I can switch between these by using an image/text toggle on the top right hand corner of the display.

If I unpack the file it gives HDImages and Mobi7 folders. The first is empty; the second contains book.html, content.opf, and toc.ncx files, as well as an Images sub-folder, which contains the page images, thumbnail images, and what looks like images for the book.html file.

Although I've searched several times, I can't find any documentation referring to this dual display option. Can someone point me in the right direction please?

[jhowell]

What sort of documentation are you searching for? Are you looking for general information or something specific enough that you could write code based on it?

I don't know of any online documentation on this. Perhaps someone else will link to some. In the mean time here is some general information.

Magazines with the ability to switch between article text and page images can be in either MOBI or KFX format. The magazine you see in the Kindle for iOS app is likely delivered in KFX format. If you download the same magazine from Amazon's website using "Download & transfer via USB" you will get it in MOBI format. Both accomplish the same thing but use different methods to achieve it. I will describe the MOBI version since that is what you have examined already.

MOBI is a proprietary binary format. Kindleunpack attempts to create standard EPUB files that correspond to the content of MOBI file. There are some things that it does not currently handle and the special fields used in periodicals is one of them.

In the MOBI file the index structure that corresponds to the NCX has additional fields that kindleunpack ignores and so they do not appear in the recreated NCX that it produces. In the NCX file produced from your magazine you will see a list of entries labeled with page numbers that link to content in the HTML file of the book. Missing from that, but present in the MOBI file, are also links to the full size image and thumbnail image of each page.

Some magazines have even more detailed information, indicating which rectangles on which each page correspond to the content contained in articles.

[PaulFraser]

Thanks for your reply. I'd like to be able to create an ebook that has the same dual format options, and would like to know what software (if any) can achieve this (I guess this is beyond Amazon's Kindle Creation software. Does InDesign do this? Framemaker? Or do I have to learn to use CSS?)

FWIW, the unpack came from a .prc file.

Originally Posted by jhowell

What sort of documentation are you searching for? Are you looking for general information or something specific enough that you could write code based on it?

[jhowell]

As far as I can tell the source format for those magazines is Adobe InDesign. I don't know how they are processed to become Kindle magazines. I suspect that the ability to do that is only made available to major magazine publishers.

[Hitch]

Originally Posted by jhowell

As far as I can tell the source format for those magazines is Adobe InDesign. I don't know how they are processed to become Kindle magazines. I suspect that the ability to do that is only made available to major magazine publishers.

I can tell you absolutely that that is an option only available to major publishers. It's not remotely available to self-pubs.

Hitch

[PaulFraser]

Originally Posted by Hitch

I can tell you absolutely that that is an option only available to major publishers. It's not remotely available to self-pubs.
Hitch

Thanks. I'd be interested in more information nonetheless (what the format is called etc.) and whether it might be possible to create a mobi of that type outside the Amazon ecosystem.

[Doitsu]

Originally Posted by PaulFraser

Thanks. I'd be interested in more information nonetheless (what the format is called etc.)

These files are often referred to as master mobi files or dual mobi files.

Originally Posted by PaulFraser

[...] and whether it might be possible to create a mobi of that type outside the Amazon ecosystem.

You can create these files with Calibre. (You'll need to select Preferences > Output options > Mobi output > Mobi file type: both > Apply before the conversion.)
I stand corrected.

[jhowell]

Originally Posted by Doitsu

These files are often referred to as master mobi files or dual mobi files.

No, that is not the sort of dual format being referred to in this thread. It is about magazines being able to switch between page image view and article view.

[Hitch]

Originally Posted by PaulFraser

Thanks. I'd be interested in more information nonetheless (what the format is called etc.) and whether it might be possible to create a mobi of that type outside the Amazon ecosystem.

No, it's not possible. It requires (at this time) proprietary Amazon coding, software (internal to them and not available outside of their hallowed halls) and device functionality.

Hitch