#1305 epub-3 video compatibility with i-world AND other worlds

output: ePub
open
nobody
None
5
2014-08-16
2013-06-15
Gérard Vidal
No

Hi,
When an epub3 is built from a docbook containing a video the result is a html5 with a video tag with an src attribute that looks like this :

        <div class="figure" id="idp179296">
            <div class="figure-title">Figure 1. Le film de la descente vers le sol martien</div>
            <div class="figure-contents">
                <div class="mediaobject">
                    <video class="videodata" src="media/curiosityLanding.mp4"></video>
                </div>
            </div>
        </div>

But with such a solution the video in the epub3 can be read only by devices mp4 compatible and if we use a webm video instead, we get the symetric situation. To produce an epub3 compatible with both worlds it is needed to provide the two formats. It is not possible to reach that goal with an attribute, it is necessary to use source tag which may look like this:

          <div class="figure" id="idp179296">
            <div class="figure-title">Figure 1. Le film de la descente vers le sol martien</div>
            <div class="figure-contents">
                <div class="mediaobject">
                    <video class="videodata">
                        <source src="media/curiosityLanding.mp4"/>
                        <source src="media/curiosityLanding.webm"/>
                    </video>
                </div>
            </div>
        </div>

The docbook source code must of course contain yhe requested information in a form like this:

    <figure>
        <title>Le film de la descente vers le sol martien</title>
        <mediaobject>
            <videoobject>
                <videodata fileref="media/curiosityLanding.mp4" width="486" align="center" format="video/mp4">
                    <info>
                        <copyright>
                            <year>2012</year>
                            <holder>NASA JPL</holder>
                        </copyright>
                    </info>
                </videodata>
            </videoobject>
            <videoobject>
                <videodata fileref="media/curiosityLanding.webm" width="486" align="center" format="video/webm">
                    <info>
                        <copyright>
                            <year>2012</year>
                            <holder>NASA JPL</holder>
                        </copyright>
                    </info>
                </videodata>
            </videoobject>
        </mediaobject>
    </figure>

I have peviously submitted this question as requested feature #458 but I think it could be considered as a bug because the epub3 produced with only one video format cannot be seen by all devices and when both formats are provided in docbook, part of the information is lost during XSL Transform to epub3.

Thanks for the work.

Discussion

  • Robert Stayton
    Robert Stayton
    2014-01-17

    This issue was discussed at the last DocBook Technical Committee meeting. The Committee decided to make the necessary changes to the DocBook schema for version 5.1, which is currently in Candidate Release.

    https://lists.oasis-open.org/archives/docbook-tc/201312/msg00005.html

    Once the schema reaches final approval, the stylesheet will be updated to handle the new feature.