A simple interactive graphics facility

This paper describes the incorporation of a graphics facility into an existing interactive system. Emphasis is placed on the importance of an inexpensive system with a simple user interface. Details of some implementation considerations are given.     

SUPERMAC—A macro facility that can be added to existing compilers

SUPERMAC is a macro facility that can be added to an existing high-level language as a runtime library. The design aim is to make macros significantly easier to use; this is done by employing a programming language and an environment already familiar to the user.     

Eye and gaze tracking for interactive graphic display

This paper describes a computer vision system based on active IR illumination for real-time gaze tracking for interactive graphic display. Unlike most of the existing gaze tracking techniques, which often require assuming a static head to work well and require a cumbersome calibration process for each person, our gaze tracker can perform robust and accurate gaze estimation without calibration and under rather significant head movement. This is made possible by a new gaze calibration procedure that identifies the mapping from pupil parameters to screen coordinates using generalized regression neural networks (GRNNs). With GRNNs, the mapping does not have to be an analytical function and head movement is explicitly accounted for by the gaze mapping function. Furthermore, the mapping function can generalize to other individuals not used in the training. To further improve the gaze estimation accuracy, we employ a hierarchical classification scheme that deals with the classes that tend to be misclassified. This leads to a improvement in classification error. The angular gaze accuracy is about horizontally and vertically. The effectiveness of our gaze tracker is demonstrated by experiments that involve gaze-contingent interactive graphic display.Received: 21 July 2002, Accepted: 3 February 2004, Published online: 8 June 2004 Correspondence to: Qiang Ji     

A pattern matching macro processor

A general-purpose pattern matching macro processor is described. Macro patterns can be defined using regular expressions. Macro calls are treated by balancing pattern matching at the token unit level, allowing options, alternatives and repetition. Thus, text in a language with a nested structure can be dealt with. In a macro body, Algol-style macro-time operations are allowed, which improves writing and reading. Our macro processor can also be used as a tool for language conversion since it incorporates a feature to declare language-dependent constructs such as comments, string notations and parentheses pairs. Although our macro processor is not biased towards any particular language, it has successfully converted an Algol 68-style text into a Fortran text. Problems of language conversion using macros are briefly discussed based upon the experience obtained through this macro processor.     

An interactive example-driven approach to graphics recognition in engineering drawings

An interactive example-driven approach to graphics recognition in engineering drawings is proposed. The scenario is that the user first interactively provides an example of a graphic object; the system instantly learns its graphical knowledge and uses the acquired knowledge to recognize the same type of graphic objects. The proposed approach represents the graphical knowledge of an object in terms of its structural components and their syntactical relationships. We summarize four types of geometric constraints for knowledge representation, based on which we develop an algorithm for knowledge acquisition. Another algorithm for graphics recognition using the acquired graphical knowledge is also proposed, which is actually a sequential examination of these constraints. In the algorithm, we first guess the next component’s attributes (e.g., size, position and orientation) by reasoning from an earlier found component and the constraint between them, and then search for this hypothetical component in the drawing. If all of the hypothetical components are found, a graphic object of this type is recognized. For improving the system’s recognition accuracy, we develop a user feedback scheme, which can update the graphical knowledge from both positive (missing) and negative (mis-recognized) examples provided by the user for subsequent recognition. Experiments have shown that our proposed approach is both efficient and effective for recognizing various types of graphic objects in engineering drawings. This paper is an extension of our papers published in ICDAR2003 and GREC2003.     

The design of an interactive graphics system for the display of meteorological fields

We describe a computer graphics system for the display of meteorological fields (such as plots of temperature and pressure). Much of the design effort has gone into the command processor which uses the usual command format of VERB PARAMETER = VALUE … The parameter and values are defined in terms of a tree sructure and the program searches as much of the tree as is necessary to make an unambiguous indentification of a token (where such an identification is possible). Because of this, commands can generally be abbreviated to the format VERB VALUE. This shortened form is possible even when the value of the command parameter is numerical. This is achieved by always specifying the units of numerical values (such as 5 days, 24 hours, 1000 millibars, etc.). The command format allows the user to manipulate a number of fields to form derived fields such as the difference of two pressure forecasts. The use of defaults for all parameters (which change as the user requests plots), reduces the amount of typing required to a minimum. A ‘Help’ facility aids the user in his choice of commands.     

MAP: A Pascal macro preprocessor for large program development

The programming language Pascal was originally designed for teaching introductory programming. Currently, however, production systems use it as the primary implementation language. This paper describes extensions of Pascal intended to aid the large program developer. The extensions are implemented in a macro preprocessor MAP, which supports constant expression evaluation, source file inclusion, conditional compilation and macro substitution. While each of these features can be used independently, they are all implemented with a simple, uniform syntax. Furthermore, in keeping with the spirit of Pascal, an attempt has been made to make the facilities straightforward and simple. The design and implementation details are discussed.     

A program structuring preprocessor for a macro assembly language

This paper deals with design considerations and implementation of a program structuring preprocessor for a macro assembly language. The macro assembly language is used for writing the code generation pass of a compiler. Macro instructions become lengthy, tedious and cumbersome when they incorporate some mild code improvement. This is chiefly because the macro assembly language lacks an adequate program structuring facility. Program structuring is a great help in improving ease of programming and the under-standability of the expansion control statements of a macro instruction in such a kind of programming. Considerations on the design of the source language and the outline of implementation are described. The design objective is ease of implementation and ease of use, and is fairly well satisfied by the language.     

Aesthetic geometry evolution in a generic interactive evolutionary design framework

An interactive evolutionary design framework is presented which provides a testbed for the development and exploration of a range of visual aesthetic design spaces. A commercial 3D digital content development software package is used to leverage the strength of existing 3D algorithm implementations and familiar interfaces and tools. The domain of non-representational 3D forms sculpted with a series of non-linear deformers is discussed as the primary example. Additional simple problem domains are shown which are being developed to serve as examples for non-programmer artists and designers who are familiar with digital content authoring in Maya. These examples will enable such individuals to rapidly construct their own interactive evolution systems. Matthew Lewis, Ph.D.: He is a researcher at The Advanced Computing Center for the Arts and Design (ACCAD) at The Ohio State University, where he received his M.S. (1993) and Ph.D. (2001) degrees in Computer Science. His research interests include evolutionary design, generative art, and data remapping for artistic performance and installation. Keith Ruston: He is a student at The Ohio State University where he has earned his B.S. in Computer Science & Engineering (2003) and is currently pursuing his M.S. His major field of study is graphics and animation. His career goals include working in the animated film industry and/or computer game development.     

Iterative process of design and evaluation of icons for interactive TV menu

This paper shows an iterative process of design and evaluation of icons for future interactive TV services. In doing the RNRT (French National Network of Research in Telecommunications) iTV project, we tried to generate icons easy to identify, associate and memorise for 32 categories and services of our iTV system.

Through an iterative process, the Multiple Index Approach was applied until an acceptable icon set was achieved. In addition to existing evaluation criteria such as the intuitiveness, associativeness, preference and suitability with subjective certainty of users, we emphasised the importance of the learnability measured by recall tests.

As a conclusion, we propose a methodology of icon design and evaluation for information appliances that integrate unfamiliar features with common users.     

Personal orchestra: a real-time audio/video system for interactive conducting

We present the first multimedia system to conduct a realistic electronic orchestra. Users can control tempo, dynamics, and instrument emphasis of the orchestra through natural conducting gestures with an infrared baton. Using gesture recognition and tempo adjustment algorithms, the system plays back an audio and video recording of an actual orchestra that follows the users conducting in real time. A major achievement of this system is its ability to vary playback speed in real time while avoiding audio artifacts such as pitch changes. The system has been deployed as an exhibit and has become a major attraction of a large Vienna-based music exhibition center.An erratum to this article can be found at     

Iterative process of design and evaluation of icons for interactive TV menu

This paper shows an iterative process of design and evaluation of icons for future interactive TV services. In doing the RNRT (French National Network of Research in Telecommunications) iTV project, we tried to generate icons easy to identify, associate and memorise for 32 categories and services of our iTV system.

Through an iterative process, the Multiple Index Approach was applied until an acceptable icon set was achieved. In addition to existing evaluation criteria such as the intuitiveness, associativeness, preference and suitability with subjective certainty of users, we emphasised the importance of the learnability measured by recall tests.

As a conclusion, we propose a methodology of icon design and evaluation for information appliances that integrate unfamiliar features with common users.     

Paradigms for the design of interactive drama

The essential purpose of drama, whether it is theatre, film or television, is to evoke subjective experience in its audience. The advent of interactive digital television opens up many new possibilities for the structure and presentation of drama and the way in which people may engage with it. However, the design of interactive, computer-based environments requires theoretical and practical bases that are largely new to the dramatic arts. This paper describes research which is exploring the convergence of ideas and design models from a range of traditional sources including HCl, psychology, the performing arts and media production for this new media form. It starts by reevaluating two traditional dramatic paradigms, Stanislavski's Realism and Brecht's objectivity, and contrasts them with Boal's spect-actor paradigm in which audiences become direct participants in the drama. Although existing technology cannot enable a faithful computer based implementation of the spect-actor paradigm, the model may be approachable in various ways and thus provides a useful goal for designers of interactive drama. The realities of designing and producing interactive drama are illustrated with a practical example. The paper concludes with a discussion of the implications of the work for the design of interactive drama.     

DIALOG: A scheme for the quick and effective production of interactive applications software

DIALOG is a collection of routines, including a main ‘driver’ program, which is used by an applications programmer as the user interface to interactive applications programs. The routines handle command analysis, data input and editing, as well as processing standard commands such as HELP. DIALOG offers, with no extra effort from the applications programmer, not only a simple interface for first-time users which gives complete instruction in using the program, but also a ‘command driven’ interface for more experienced users. DIALOG permits the quick and effective production of interactive applications software by programmers with no previous experience of writing such programs. User reaction to the programs so far produced and offered as part of a university computing service has been extremely favourable.     

Effectiveness of keyword-based display and selection of retrieval results for interactive searches

We present an approach to increasing the effectiveness of ranked-output retrieval systems that relies on graphical display and user manipulation of “views” of retrieval results, where a view is the subset of retrieved documents that contain a specified subset of query terms. This approach has been implemented in a system named VIEWER (VIEwing WEb Results), acting as an interface to available search engines. An experimental evaluation of the performance of VIEWER in contrast to AltaVista is the major focus of the paper. We first report the results of an experiment on single, short query searches where VIEWER, used as an interactive ranking system, markedly outperformed AltaVista. We then concentrate on a more realistic searching scenario, involving free query formulation, unconstrained selection of retrieval results, and possibility of query reformulation. We report the results of an experiment where the use of VIEWER, compared to AltaVista, seemed to shift the user effort from inspection to evaluation of results, increasing retrieval effectiveness, and user satisfaction. In particular, we found that the VIEWER users retrieved half as many nonrelevant documents as the AltaVista users while retrieving a comparable number of relevant documents. Published online: 22 September 2000     

A display package for CAD of control systems

A multi-access computer system has been installed at the Control Systems Centre of the University of Manchester Institute of Science and Technology. The application of this computer to research into the computer aided design of industrial control systems involved the connection of two keyboard display terminals to the system. The ARDS storage tube displays chosen had the advantages of being teletypewriter compatible and not requiring the connection of a satellite computer A graphics package for the entry and structuring of data derived from the stability analysis of control systems was required as soon as possible after the installation was commissioned. The initial package enabled data to be entered by program and then selected and plotted by keyboard requests. Translation, scaling, alteration of the method of plotting (with points or vectors) and the selection of different items for the display were all carried out by keyboard interaction For long term CAD work a more extensive graphics package was required, the specification was determined following feedback from users of the initial package. It provided additional facilities for graphic interaction, alphanumeric annotation of the displays, specialized drawing and data entry functions and the storing of any pictures built up by the user, as well as a more linked data structure. The structure and facilities of this package are described.     

The syntax of interactive command languages: A framework for design

Various qualities of simple command languages, such as ease of use and flexibility, are defined in terms of syntax. Certain design attributes—namely style, structure and level of abstraction—are described for command languages, and these attributes are shown to strongly influence the defined qualities. Commands are designed for three functions to show how the design trade-offs are made in light of the qualities and attributes discussed.     

A probabilistic model for interactive decision-making

A probabilistic reasoning model is defined where the decision maker (d.m.) is engaged in a sequential information-gathering process facing the trade-off between the reliability of the achieved solution and the associated observation cost. The d.m. is directly involved in the proposed flexible control strategy, which is based on information-theoretic principles. The devised strategy works on a Bayesian belief network that allows the efficient representation and manipulation of the knowledge base relevant to the problem domain. It is shown that this strategy guarantees a constant factor approximate solution with respect to the optimum of the decision problem. Some application examples are also discussed.