ETD Guide/Technical Issues/Overview: hardware, software, multimedia, scripts, encoding, document representations\conversions
Preparing an ETD is somewhat like preparing a book to be given to a publisher, and then distributed electronically (and perhaps on paper). There are many aspects to this process, briefly summarized in the next paragraphs.
First, there is the hardware perspective.
Authors of ETDs nowadays almost always use a computer for this activity. In many cases this means a personal computer, though in some cases a terminal, PDA, or another device might be chosen. With the continuing increase in performance and functionality, given a particular price, it is becoming more feasible for authors to have their own computers. However, in some cases, an office or laboratory or shared computer might be used, at least from time to time.
- Other Devices
In addition to a computer, authors may use other special devices to prepare parts of the ETD. In particular, in the case of multimedia content, parts might result from using a scanner, digital camera, digital camcorder, slide scanner, microphone, sound card, MIDI device, or other special equipment. Special systems might be used for audio or image or video editing, though in some cases such editing can be done on a PC.
Second, consider software
- Software Editors
Software that can help with ETD production may be specialized by role. Text editors like Wordpad, vi, and emacs allow creation of files of characters, often encoded in ASCII. More powerful word processors may allow handling of more extensive sets of characters, like UNICODE, and entry of character codes from large sets (e.g., for Chinese, Japanese, or Korean texts).
- Separate Editors
Separate editors may support multimedia content. Photoshop handles photos and other images, for example, while Sound Forge allows manipulation of audio files. Premiere is a tool for video editing that also can process audio, animations, and other related components. Editing tools may handle conversions as well, or accept the results of conversion. Ultimately, one may think of authoring, capture, conversion, and editing tools for all media types as all having the objective of amassing a pool of components that go into the ETD.
Large documents thus are made of pools of content objects, and students can use special software to integrate the content into a coherent whole. A simple integration is to have a linear structure, like a book, where all the components are ordered, as in a sequence of pages, manipulated by a word processor. It is simple for images to be included in such a work, as long as sizing is adjusted. However, large images, and other multimedia content (e.g., audio), must be integrated in a different fashion.
Such integration may involve linking (as in hypermedia, found in many Web sites). Additional interactivity may require a tailored hypertext system (e.g., Toolbook, Guide), or a multimedia integration package (e.g., Director or AuthorWare). Such a system will support synchronization (e.g., using the WWW standard, SMIL), or complex performances. Ultimately, the most sophisticated integration of content with reader interaction requires a programming language. In the case of multimedia languages, this typically is called a scripting language. However, students can also use general purpose languages like Java for sophisticated handling of content along with interaction.
Third, consider representation. Each content object must have a representation scheme, depending on its form. Text components are characterized by character encoding, as well as supplemental information to support presentation (e.g., font, size, style). Multimedia components are encoded in suitable forms, depending on resolution or other measure of level of detail, compression, and other attributes. For the purpose of archival preservation, the representations used for content objects (e.g., UNICODE, MPEG), as well as those used to describe the organization and rendering of content (e.g., SMIL), will be in standard forms.
Fourth, for an ETD or other large work, one can choose from archival forms, and related software support.. In particular, for more detail about software, see the next subsection. For details about PDF, SGML/XML, and other matters, see the next sections.
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