I'll see if I can make this simple and clear:
Opening the epub (unzipping it) gives the usual three files/folders..META-INF, OPS, and mimetype.
In the OPS folder are two other folders--/CSS and /images--along with a lot of individual xml files that comprise the articles themselves, including one .ncx and one .opf file, and on file called 'ReplicaMap.xml'.
I pulled one image out of the /images folder and simply copied it to a folder on my EVO cellphone, as well as to my color Nook, and then opened it. On my EVO if I choose simply to 'view the file' it opens and is fully zoomable. (Curiously to me, if I open it using "ES Image Browser" it isn't zoomable..)
Now, if I load the ePub file to my EVO read it with a reader app (Aldiko), it displays the article files which have smaller versions of the images included in each article. The magazine looks and behaves basically like a regular ePub book would as far a changing pages, chapters, etc. But, the images are -not- zoomable...they are static...and look only like thumbnails or small versions embedded with each article.
However, If I open the ePub on the color Nook, it defaults to a version of the magazine that is an image-based version. These images are found under the /images directory in a subfolder called /pages. It seems clear to me that this is all being done using the /OPS/ReplicaMap.xml file since that is the only place with coding that calls these specific images. How the Nook knows to go to ReplicaMap.xml and show that layout first and not the default layout that opens on a PC or on my EVO is beyond me. Maybe there is something in the Nook software as a reader that tells it to always go with ReplicaMap.xml first if it exists.
Anyway, the whole point of this is that when the images are displayed on the Nook (via ReplicaMap.xml) they appear as if you're looking at a two page spread of the actual magazine pages and you can pinch-to-zoom on them and enlarge them, etc.
Somehow, even though everything is buried in the same ePub, if the images are displayed one way (via ReplicaMap) they are zoomable...but displayed as part of the pages of articles they are not. It's frustrating.
Folders:
META-INF
OPS
+CSS
+images
+pages
ReplicaMap.xml looks like this:----------------------------------------------
<?xml version="1.0" encoding="UTF-8"?> <ReplicaMap xmlns="http://www.hp.com/schemas/imaging/ereader/hff">
<Title>Popular Science - Sample Issue</Title>
<Pages>
<Page pageNum="0" file="images/pages/pg-01.jpg"
thumbFile="images/pages/pg-01-thumb.jpg">
<Group ePubTarget="article_1-1.xml"/>
</Page>
<Page pageNum="1" file="images/pages/pg-07.jpg"
thumbFile="images/pages/pg-07-thumb.jpg"/>
<Page pageNum="2" file="images/pages/pg-08.jpg"
thumbFile="images/pages/pg-08-thumb.jpg"/>
<Page pageNum="3" file="images/pages/pg-16.jpg"
thumbFile="images/pages/pg-16-thumb.jpg">
<Group ePubTarget="article_16-1.xml">
----SNIPPED OUT A LOT FROM THE MIDDLE----
<TocEntry title="The Toughest Bike Tire">
<Summary>Better known for making rubber seals for NASA, Hutchinson is the first company to get airless bicycle tires right. The Serenity consists of a solid tube-like core made from a foam-type material, and</Summary>
<Page pagenum="34"/>
<Article refid="a1948316537"/>
</TocEntry>
</TOC> </ReplicaMap>
---------------------------------------------------------------
Still...all I really need to do is to have a link that 'views' an image so it is zoomable. If there's a simple way to do that then I'd be happy.
Thanks,
-JTT