Multimedia Production and Authoring Tools

Published by Emil Abraham, 



Multimedia authoring is a process of assembling different types of media contents like text, audio, image, animations and video as a single stream of information with the help of various software tools available in the market.

Topics covered in this article:
  • Multimedia authoring tools
    • Features of authoring softwares
  • Types of authoring tools
    • Card- and page-based
    • Icon-based
    • Time-based
  • Navigation structures
    • Linear
    • Hierarchical
    • Non-linear
    • Composite
  • Compositing
    • Matting

Multimedia Authoring Tools
  • Multimedia authoring tools give an integrated environment for joining together the different elements of a multimedia production.
  • It gives the framework for organizing and editing the components of a multimedia project.
  • It enables the developer to create interactive presentation by combining text, audio, video, graphics and animation.

Multimedia authoring softwares have the following features:
Editing Features
Most authoring environment and packages exhibit capabilities to create, edit and transform different kinds of media that they support.
For example, Macromedia Flash comes bundled with its own sound editor. This eliminates the need for buying dedicated software to edit sound data. So authoring systems include editing tools to create, edit and convert multimedia components such as animation and video clips.
Organizing Features
The process of organization, design and production of multimedia involve navigation diagrams or storyboarding and flowcharting.
Some of the authoring tools provide a system of visual flowcharting or overview facility to showcase your project's structure at a macro level. Navigation diagrams help to organize a project. Many web-authoring programs like Dreamweaver include tools that create helpful diagrams and links among the pages of a website.
Programming features
    • Visual programming with icons or objects - It is the simplest and easiest authoring process. For example, if you want to play a sound then just click on its icon.
    • Programming with a scripting language - Authoring software offers the ability to write scripts for software to build features that are not supported by the software itself. With script you can perform computational tasks - sense user input and respond, character creation, animation, launching other application and to control external multimedia devices.
Document Development tools- Some authoring tools offers direct importing of pre-formatted text, to index facilities, to use complex text search mechanism and to use hypertext linking tools.
Interactivity Features- Interactivity empowers the end users to control the content and flow of information of the project. Authoring tools may provide one or more levels of interactivity.
    • Simple branching - Offers the ability to go to another section of the multimedia production.
    • Conditional branching - Supports a go to base on the result of IF-THEN decision or events.
Playback Features
When you are developing multimedia project, you will continuously assembling elements and testing to see how the assembly looks and performs. Therefore authoring system should have playback facility.
    • Supporting CD-ROM or Laser Disc Sources- This software allows over all control of CD-drives and Laser disc to integrate audio, video and computer files. CD-ROM drives, video and laserdisc sources are directly controlled by authoring programs.
    • Supporting Video for Windows- Videos are the right media for your project which are stored on the hard disk. Authoring software has the ability to support more multimedia elements like video for windows.
Hypertext- Hypertext capabilities can be used to link graphics, some animation and other text. The help system of window is an example of hypertext. Such systems are very useful when a large amount of textual information is to be represented or referenced.
Cross-Platform Capability- Some authoring programs are available on several platforms and provide tools for transforming and converting files and programs from one to the other.
Run-time Player for Distribution - Run time software is often included in authoring software to explain the distribution of your final product by packaging playback software with content. Some advanced authoring programs provide special packaging and run-time distribution for use with devices such as CD-ROM.
Internet Playability - Due to Web has become a significant delivery medium for multimedia, authoring systems typically provide a means to convert their output so that it can be delivered within the context of HTML or DHTML.
Types of authoring tools
  • Card- and page-based tools.
  • Icon-based, event-driven tools.
  • Time-based tools.

Card- and page-based tools.
  • In these authoring systems, elements are organized as pages of a book or a stack of cards. In the book or stack there are thousand of pages or cards available. These tools are best used when the bulk of your content consists of elements that can be viewed individually, for example the pages of a book or file cards in card file. You can jump from page to page because all pages can be interrelated. In the authoring system you can organize pages or cards in the sequences manner. Every page of the book may contain many media elements like sounds, videos and animations.
  • Card‐ and page‐based authoring systems provide a simple and easily understood metaphor for organizing multimedia elements.
  • It contains media objects such as buttons, text fields, and graphic objects.
  • It provides a facility for linking objects to pages or cards.
  • One page may have a hyperlink to another page that comes at a much later stage and by clicking on the same you might have effectively skipped several pages in between. Some examples of card or page tools are: Hypercard(Mac), Tool book (Windows), PowerPoint (Windows), Supercard(Mac)

Icon-based or Event-driven authoring tools
Icon-based tools give a visual programming approach to organizing and presenting multimedia. First you build a structure or flowchart of events, tasks and decisions by dragging appropriate icons from a library.
Each icon does a specific task, for example- plays a sound, open an image etc. The flowchart graphically displays the project's logic.
When the structure is built you can add your content text, graphics, animation, video movies and sounds. A nontechnical multimedia author can also build sophisticated applications without scripting using icon based authoring tools.
Some examples of icon based tools are: Authorware Professional (Mac/Windows), Icon Author (Windows)

Time based authoring tools
Time based authoring tools allow the designer to arrange various elements and events of the multimedia project along a well defined time line. By time line, we simply mean the passage of time. As the time advances from starting point of the project, the events begin to occur, one after another. The events may include media files playback as well as transition from one portion of the project to another. The speed at which these transitions occur can also be accurately controlled. These tools are best to use for those projects, wherein the information flow can be directed from beginning to end much like the movies.
Some example of Time based tools are: Macromedia's Director, Macromedia Flash

Object oriented authoring tools support environment based on object.
Each object has the following two characteristics:
State or Attributes - The state or attributes refers to the built in characteristics of an object. For example, a color T.V has the following attributes:
    • Color receiver
    • Volume control
    • Picture control
    • 128 channels
    • Remote control unit
Behavior or Operations - The behavior or operations of an object refers to its action. For example, a T.V can behave in any of the following manner at a given point of time:
    • Switched on
    • Switched off
    • Displays picture and sound from
    • A TV cable connection
    • A TV transmitter
    • A DVD
    • A VCR
  • In these systems, multimedia elements events are often treated as objects that live in a hierarchical order of parent and child relationships. These objects use messages passed among them to do things according to the properties assigned to them. For example, a video object will likely have a duration property i.e how long the video plays and a source property that is the location of the video file. This video object will likely accept commands from the system such as play and stop. Some examples of the object oriented tools are: mTropolis (Mac/Windows), Apple Media Tool (Mac/Windows), Media Forge (Windows)


Navigation structures

Linear:Users navigate sequentially, from one frame of information to another
Hierarchical:Users navigate along the branches of a tree structure that is shaped by the natural logic of the content
Nonlinear: Users navigate freely through the content of the project, unbound by predetmined routes
Composite: Users may navigate freely, but are occasionally constrained to linear presentations of movies or date.

Designing the structure
  • Consideration on Hot Spot, button and icon
    • Hot spot: Areas of the screen that are ‘clickable’.
    • Button: Provide button feedback whenever possible
  • Have a unique ‘pressed’ or ‘clicked’state
  • In HTML, feedback is provided by colour changing
  • Icon: Avoid forcing users to learn special icons in your project. Try to follow the design convention set by other leading software.
Designing the Appearance
  • Usually called the user interface design or the look and feel design.
  • The target is to facilitate communication, provide entertainment, elicit emotion, etc
  • The graphic design of your multimedia product is the users first impression. A well design interfaces provide a good match between the user’s task needs, skill level and learning ability and will lead to satisfied and productive users.

Compositing


Compositing is the process through which two or more images combine to make the appearance of a single picture. Typically, paste a foreground object onto a new background. The composite process can be done on-set and in-camera or during Post-Production. There are dozens of different ways to composite shots but perhaps the most common example is when a weatherman is placed in front of a greenscreen with the weather details behind them.
It is widely used for,
  • Movie special effect
  • Combining graphics & film
  • Photo retouching
    • Change background
    • Fake depth of field
    • Page layout: extract objects, magazine covers
Compositing techniques
  • Composting techniques known as chroma keying that remove all areas of a certain color from a recording - colloquially known as "bluescreen" or "greenscreen" (because those are the most popular colors used) are probably the best-known and most widely used modern techniques for creating traveling mattes.



  • Computer-generated imagery, either static or animated, is also often rendered with a transparent background and digitally overlaid on top of modern film recordings using the same principle as a matte - a digital image mask.
  • Matting
    Mattes are used to combine a foreground image (e.g. actors on a set or a spaceship) with a background image (e.g. a scenic vista or a starfield with planets). In this case, the matte is the background painting. In film and stage, mattes can be physically huge sections of painted canvas, portraying large scenic expanses of landscapes.
In film, the principle of a matte requires masking certain areas of the film emulsion to selectively control which areas are exposed. However, many complex special-effects scenes have included dozens of discrete image elements, requiring very complex use of mattes, and layering mattes on top of one another. For an example of a simple matte, we may wish to depict a group of actors in front of a store, with a massive city and sky visible above the store's roof. We would have two images—the actors on the set, and the image of the city—to combine onto a third. This would require two masks/mattes. One would mask everything above the store's roof, and the other would mask everything below it. By using these masks/mattes when copying these images onto the third, we can combine the images without creating ghostly double-exposures. In film, this is an example of a static matte, where the shape of the mask does not change from frame to frame. Other shots may require mattes that change, to mask the shapes of moving objects, such as human beings or spaceships. These are known as traveling mattes. Traveling mattes enable greater freedom of composition and movement, but they are also more difficult to accomplish.