Friday, February 8, 2013

HTML Widgets Made Easy: External Video Player Example

The iBookstore limits the size of of *.ibooks files created with iBook Author (henceforth, IBA) to 2 GB and recommends that you keep the size of your iBook file under one gigabyte if possible in order to avoid taking too much space on your readers' iPads as well as to avoid your readers having to endure long download times. Although including video that is internal to your IBA project is a simple drag and drop application using the Media Widget in IBA, that kind of video will very quickly increase the size of your iBook and may place an unwelcome burden on some of your readers.

The alternative is to include external video in your IBA project using a custom made HTML Widget. The big advantage is that a one megabyte HTML Widget can play a 70 megabyte video in your iBook. The downside, of course, is that the reader must have an active internet connection and the availability of the video must be maintained. If a video used in your iBook should become unavailable, you can provide your readers with a free upgrade correcting that issue via the iBookstore's versioning feature.

Unfortunately, many people are persuaded not to use this approach because it involves writing HTML code but this post will offer you a way around that obstacle. If you can use a text editor, you can modify an HTML widget template that plays an external video that you select for your iBook. Here's how:

As you'll learn from
this Apple support document, an HTML widget is nothing more than a collection of text files enclosed in a folder with the suffix ".wdgt" added to it. On the Mac, adding that suffix to the folder name changes the appearance of the folder into a widget icon. The minimum HTML widget contains three files: a Default.png file, an index.html file and an info.plist file. I have prepared an HTML widget that you can use as both an example and a template. It is a ZIP archive containing a complete working widget that you can add to a test IBA project. Once you have it in an IBA project you may use the Preview function to see how it works in the on an iPad. Download that HTML widget here and then double-click on it to extract it.

This example widget plays a video called "Open Access Explained" that is hosted on a server that I have access to. In this tutorial, I will show you how to open the widget and modify it so that it will play another video, one that is on a server that I do not have access to, a video that you choose. All I'll have to do to accomplish this feat is to open the widget, change the Default.png file and edit the text of the index.html and info.plist files so that they reference a different video. It's just that easy.

Of course that video must be playable on an iPad so no Flash. These
tech specs provide all the necessary details. The great thing about video on the iPad is that the HTML 5 video tag works without having to create multiple fallback versions of your video (*.mp4, *.ogg and *webm) as one would have to do on a web site. As long as it's using the MPEG-4 H.264 video and AAC audio CODECs, it can be in either a MOV, MP4 or M4V container. More simply, if the video plays on your iPad, it will play in this widget.

The video that I'll be modifying the widget to use in this tutorial is: Because I'll be changing the widget to play another movie with different dimensions, I'll need to create a new Default.png file and change all of the references from the old video to the new video. I'll be using the BBEdit text editor but any plain text editor such as TextEdit will do just as well. Here's a screencast showing how this is done. Click HERE or click the image below.

Caveats: Some video services such as Vimeo and YouTube go to great lengths to tie their hosted video to their own web sites so that they can generate data about you and get paid for exposing advertising to you. Thus, it is just a little more difficult to use these videos in an iBook but it can be done. I may take that topic up in the next post.


• About the "auto play" attribute. You'll notice that I use the optional "auto play" attribute in the HTML 5 "video" tag. All HTML widgets take over the entire screen when invoked. Under iOS 6.x (tested), tapping this external video player widget will bring the poster (Default.png) image to full size atop a white background that also displays the widget's title and caption as well as a close button. A standard iOS "play" icon will be superimposed on the center. The video will begin to play automatically without the reader having to tap this play button. The time that auto play takes depends upon the size of the video and the speed of the network. The operating system tries to estimate when it can play the external video without interruption. The reader can always tap the play button prior to auto play. Simply delete the "auto play" attribute if you rather not have this feature operative.

• About the "controls" attribute. I also use the optional "controls" attribute. This provides the reader with a standard video controller with which they can control playback of the video such as audio volume and two "full screen" options as well as a scrubber for moving the play head to arbitrary points along the time line. Simply delete the "controls" attribute if you'd rather not have this feature be available to your readers. The following image shows these various controls and their effects.


Safari HTML 5 Audio and Video Guide

iBooks Author: About HTML widget creation

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