next up previous contents
Next: Interactions in Virtual Up: Architectures and Interaction Previous: The cognitive coprocessor

Architectural qualities and principles

In [141], Hill and his coauthors have defined five qualities for multimodal and multimedia interfaces:

  1. Blended modalities: The user should be able to blend modes at any time.
  2. Inclusion of ambiguity: Input modes that yield ambiguous or probabilistic input are desirable when appropriate.
  3. Protocol of cooperation: Intervention on input and output modules should be available at any time.
  4. Full access to the interaction history: The interpreted levels of interaction history must be accessible on-line as well as after the finishing of the interaction session.
  5. Evolution: The interfaces have to be open to improvements without the need for a complete reimplementation.
By investigating traditional interface architectures, they found that semantics and pragmatics are usually not shared across modalities. Another drawback is the missing of ``felicitous interruption, information volunteering, and intelligent displays'', which are considered to be important interface building techniques. The different modalities of traditional architectures are therefore ``noncommunicating components'', as shown in figure 4.4 .

  
Figure 4.4 : The traditional structure of modality cooperation (Taken from [141])

In the new structure proposed by Hill et al., some of the processing levels have been unified across input modalities, whereas others have been opened. Thus, ``applications [...] interact with a semantic representation of user activities rather than a syntactic one.'' The principle architecture according to this approach is shown in figure 4.5 . It is based on the principle of uniform access, which guarantees for a separation of interface aspects from the application; and the compromise of almost homogeneous representation, which tries to balance between performance (mainly: speed) achieved by specialized device drivers and access functions on the one hand, and homogeneity that allows the blending of modalities on the other hand.

  
Figure 4.5 : A better structure for modality blending (Taken from [141])



next up previous contents
Next: Interactions in Virtual Up: Architectures and Interaction Previous: The cognitive coprocessor



Esprit Project 8579/MIAMI (Schomaker et al., '95)
Thu May 18 16:00:17 MET DST 1995