ePub Books Blog

Experiment: Advancing ePub with HTML5 Video’s

There are a number of people in the eBook world who really know their ePub format – luckily for us they enjoy sharing this knowledge among the community. One of these such people is Bookworm developer, Liza Daly.

There’s a lot of a misconception around the ePub format with the belief that it is not a very advance format to work with, this is certainly not the case. Being based on several web standards, ePub can do pretty much whatever those standards can do themselves.

In a recent blog post, Liza conducted an experiment to include a HTML5 <video> in an ePub file, which she accomplished by using out-of-island XML mark-up. Okay, so this is something of a hack, and very few ePub readers will render the content (although Bookworm does), but this just goes to show there’s some power in the ePub standard.

All you ePub developers out there might want to keep an eye on Lizas blog as she will be sharing lots of ePub tips throughout this month.

Marking Up Page Numbers in the EPUB NCX

Below is an example <pageList> markup (that is valid per the NCX DTD) which can be used to mark up page numbers within ePub documents.

Note that <pageList> must be placed right after the required <navMap>, and must occur before the first optional <navList>. There may be one and only one <pageList> (but there can be any number of <navList> — of course, there can only be one <navMap>).

<pageList id="page-mapping">

  <navLabel><text>Paper Edition Page Mapping</text></navLabel>

  <pageTarget id="page-iii" value="3" type="front" playOrder="82">
    <navLabel><text>Page iii</text></navLabel>
    <content src="frontmatter.html#pageiii"/>
  </pageTarget>

  <!-- ... -->

  <pageTarget id="page-105" value="105" type="normal" playOrder="192">
    <navLabel><text>Page 105</text></navLabel>
    <content src="chap5.html#page105"/>
  </pageTarget>

</pageList>

Notes:

1. Currently there is an error in epubcheck 1.0.3 which says <pageList> must include both the id and class attributes, while they should be optional. Hopefully that bug will get fixed. The above markup includes the optional id (generally a good idea), but not the class so it will not validate to 1.0.3.
Read the full article »

epubcheck and Adobe’s page-map attribute

A couple of weeks back we had a new release of the epub validation tool as the old one was not validating documents properly. epubcheck-1.0.3 was released to fix the XMLParser as it was not allowing multiple validators to be added.

The error was first realised by Jon Noring who noticed that Adobe’s “page-map” attribute extension, which is used in the NCX , was being validated incorrectly. This extended markup can be used for mapping page numbers (to align with those in the paper book edition).

Jon Noring has posted to several communities about the page-map issue. Here’s a short extract (slightly edited); Read the full article »

Using Q tags in ePub documents

Recently I’ve been making great progress on my ePub converter but in the process I’ve come across a few areas that have needed some thought. For this short article I’m going to discuss the XHTML Quote tag.

When looking though the IDPF OPS specs I noticed that <q> tags are allowed within ePub documents. As I mark up all quotes in my master TEI documents with a <q> tag I was really happy to see this. However, when I came to test my files in Adobe Digital Editions none of my quotes showed.

After seaching around the net I also noticed that <q> tags are not supported by all web browsers (i.e. Internet Explorer). Liza Daly has also noted that the HTML 5.0 specs will depreciate Q tags – will a version of XHTML follow suite in the future? Will a future IDPF OPS spec implement that future XHTML spec?

(FYI, Liza mentioned that she is currently working on implementing <q> tags in her Bookworm reader, with a work around for IE.)

This is an area which I believe ePub developers should give some serious thought over. Even if Adobe DE go ahead and implement this feature, other readers may not necessarily follow suite.

For my own project I have decided to convert all my <q> tags into regular “quote” characters. Providing more safety both now and in the long term.

Creating an ePub document from XHTML

In my last post I talked about the ePub Books Project and how I plan to convert Project Gutenberg .txt eBooks to the ePub format and how I will make these eBooks available for download from ePubBooks.com.

I already have in place a converter to transform the PG .txt files to a TEI Master Format and also an XSLT script to convert these into XHTML. The final task now is to create a converter for TEI to the ePub format.

Before I attempt to write this converter I will need to have a much better understanding on how a book is laid out inside the ePub OEBPS Container Format (OCF) .zip archive. So I set about taking my XHTML output file and breaking it up into the appropriate parts ready to be packaged in to an .epub file.

On the whole this went fairly smoothly, although I did encounter a couple of issues, which I’ll explain at the end of this article.

Read the full article »

TOC tutorial on how to read O’Reilly ePub books on your iPhone

Andrew Savikas over on the O’Reilly TOC has written a nice tutorial on how to read your O’Reilly ePub formatted books on the iPhone using Stanza.

One thing to note about this is that he was only successful in doing so when using his MacBook Pro, he was unable to say the same about the process using Windows.

After reading his article, I have to say the whole thing seems really easy!

Andrew did bring up one of Stanza’s failings, “A lot of the formatting isn’t (yet) supported by Stanza, including lists and tables. The text appears, but without bullets or clear indentation.” Perhaps it’s understandable about tables but I am surprised that lists are not yet supported. However, the app is still in beta and we know that Lexcycle are working hard on improving it.

One thing Andrew noted in his post was that O’Reilly are also looking into releasing their titles as individual iPhone Apps. I’m not convinced by this approach myself, but hey, for you iPhone users it will if nothing else give the proper formatting that O’Reilly intended

Okay, there’s a long way to go before ePub is a format that all devices can read properly, however it’s great to see that the industry is still moving forward.

What image formats are suitable for ePub?

A question posted over on the ePub Community Group was asking what image formats are suitable for use in ePub.

As Jon Noring replied, the OPS 2.0 Specifiaction says that an OPS (ePub) Reading System must support the GIF, PNG, JPEG and SVG image formats.

These are pretty standard formats to be supported so I don’t see any problems with rendering these. But I do have some concerns regarding SVG – these of course stem form having absolutely no clue at all about the format!

Still, I am wondering if there will be any issues when rendering SVG, akin perhaps, to what we had during the browser wars.

Is there anyone out there who understands SVG and can shed some light on this matter?

Join the new EPub Community mailing list

I’m currently subscribed to a number of mailing lists, though I must confess I don’t really contribute [I hang my head in shame]. As a result of being a member I received an invitation from Jon Noring to his new YahooGroup, EPub Community — I’m starting to believe he is addicted to these lists

In the invitation email he writes,

EPub Community is intended for publication creators, developers, readers, and anyone else interested in all things related to EPub and the IDPF specifications which underlie EPub (OPS/OPF/OCF).

Although the group’s focus is likely to be fairly technical, we certainly invite and encourage non-technical discussions.

To subscribe you’ll need to do one of the follow things;

1. With your YahooID — click on the “Join this Group” button at the group’s homepage
2. Send a blank email to epub-community-subscribe@yahoogroups.com

This group is independent to the IDPF but could become a great place to discuss all things ePub.

At the moment Jon is away travelling so he has switched off the ability to make posts. He informs us that once he returns, allowing ample time for there to be a good number of subscribers, he’ll open the group for posting.

In a personal email to Jon I made a passing reference on how to write the word ePub, perhaps I’ll make my opening post on that very subject.

Looking for a guide to creating ePub documents?

I created this site because there are very few blogs, mailing lists and other resources on the ePub standard. I wanted to try and bring together the few that there are in one handy place, in the hope to make this information easily available.

I am no ePub expert myself so I’m continually searching for new information and resources to help me learn. One very useful tutorial I found was the ‘Epub Format Construction Guide‘.

Not only is this guide about creating ePub documents, it also gives some nice insights into the compliance of the ADE (Adobe Digital Editions) reader, still the most conformant reader at this time. A couple of surprising things about ADE v1.0 is that it does not support certain CSS attributes. Two big surprises were; text-transform and text-align: justify.

The tutorial itself is more like an “annotated example”, if you just wish to construct an ePub document in a quick hassle free way then this will help tremendously. Once nice thing I like about the guide is that it highlights the areas which need to be altered on a per project basis.

In the future I’m hoping to find more detailed tutorials so if you need more in-depth information, you’ll just have to reference the IDPF specifications.

You can read the ‘Epub Format Construction Guide’ at www.hxa7241.org.