DocBook 5: The Definitive Guide

Name

mediaobject — A displayed media object (video, audio, image, etc.)

Synopsis

mediaobject ::= (info? ^{db.titleforbidden.info}, alt?, (audioobject | imageobject | imageobjectco | textobject | videoobject)+, caption? ^db.caption)

Attribute synopsis

Common attributes and common linking attributes.

Description

This element contains a set of alternative “media objects.” Exactly one object will be selected and rendered.

Processing expectations

Formatted as a displayed block. The primary purpose of the mediaobject is to provide a wrapper around a set of alternative presentations of the same information.

If possible, the processing system should use the content of the first object within the mediaobject. If the first object cannot be used, the remaining objects should be considered in the order that they occur. A processor should use the first object that it can, although it is free to choose any of the remaining objects if the primary one cannot be used.

Under no circumstances should more than one object in a mediaobject be used or presented at the same time.

For example, a mediaobject might contain a video, a high-resolution image, a low-resolution image, a long text description, and a short text description. In a “high-end” online system, the video is used. For print publishing, the high-resolution image is used. For other online systems, either the high- or the low-resolution image is used, possibly including the short text description as the online alternative. In a text-only environment, either ...