Task allocation in distributed multimedia systems based on the host-satellite model

Multimedia applications require intermediate processing between media sources and sinks. In addition to end-user machines intermediate computers can be used for performing media processing. This possibility leads to the problem of allocating processing components on various computers. In this paper, we study this problem in the context of star-shaped application graphs which have to be allocated between given end-user machines (satellites) and a central computer (host). The problem is formulated in terms of best achievable bottleneck resource usage. Several approaches are considered including anapproximate scheme and two fast-heuristics. Performance measurements show the efficiency of the considered approaches. A discussion of our approach shows important differences to solutions provided for related problems of graph partitioning and mapping

Strategic questions in the development of interactive television programs

The aim of this research was to identify questions that a person developing interactive television programs could ask himself. The topic was chosen because it is currently an emerging issue in many of the countries launching digital television. The previous research in this field was reviewed including academic research, field trials in Finland, selected field trials abroad, consumer attitude surveys and expert panels. As it turned out, not much academic work had been done in the subject. The most promising work had been done in the fields of distance education and interactive narration. Five other fields were surveyed as potential sources for suitable ITV development strategies. These fields were linear drama, infomercials and homeshopping, multimedia production, www-production and virtual communities. A group of potential strategies were identified from these fields. Several methodological choices were considered. Among them were predicative methods, scenario analysis, case study method, action research, knowledge brokering and Zetterberg’s method. Finally a combination of knowledge brokering and the Zetterberg’s method was found most suitable for this research. The initial strategies were picked by the researcher from the above mentioned fields. They were then tested with a survey form that was presented to persons involved with the ITV industry. The respondents were identified from various sources and also the snowball method was applied to gather more respondents. Altogether 103 responses were received from persons in significant posts in key companies and institutions of the field. The research can be considered valid and reliable. The main conclusion of this study is that it pays in ITV-development to use the questions that have been found useful in developing film and TV scripts, www-applications, multimedia productions, virtual communities or home-shopping advertisements. Different sets of questions are useful for different ITV-genres. A useful set of questions could be identified for six different ITV genres. These genres were ITV advertising, computer game type of ITV applications, News on Demand applications, Electronic Program Guide (EPG), distance learning applications and background information for TV programs. Other results were also discovered. The following three questions were found important for all genres: 1) How can we make the program aesthetically appealing as possible? 2) How can we make the program visually compelling? 3) What type of an interface should the program have? Another result was that the following two questions that are central in film industry were not considered important for any of the ITV genres: 1) How can we have a three act structure in the program? 2) How can we arrange a happy ending for the program? The identified sets of questions will provide a good starting point for a person developing a program in the respective genre

Strategic questions in the development of interactive television programs

The aim of this research was to identify questions that a person developing interactive television programs could ask himself. The topic was chosen because it is currently an emerging issue in many of the countries launching digital television. The previous research in this field was reviewed including academic research, field trials in Finland, selected field trials abroad, consumer attitude surveys and expert panels. As it turned out, not much academic work had been done in the subject. The most promising work had been done in the fields of distance education and interactive narration. Five other fields were surveyed as potential sources for suitable ITV development strategies. These fields were linear drama, infomercials and homeshopping, multimedia production, www-production and virtual communities. A group of potential strategies were identified from these fields. Several methodological choices were considered. Among them were predicative methods, scenario analysis, case study method, action research, knowledge brokering and Zetterberg’s method. Finally a combination of knowledge brokering and the Zetterberg’s method was found most suitable for this research. The initial strategies were picked by the researcher from the above mentioned fields. They were then tested with a survey form that was presented to persons involved with the ITV industry. The respondents were identified from various sources and also the snowball method was applied to gather more respondents. Altogether 103 responses were received from persons in significant posts in key companies and institutions of the field. The research can be considered valid and reliable. The main conclusion of this study is that it pays in ITV-development to use the questions that have been found useful in developing film and TV scripts, www-applications, multimedia productions, virtual communities or home-shopping advertisements. Different sets of questions are useful for different ITV-genres. A useful set of questions could be identified for six different ITV genres. These genres were ITV advertising, computer game type of ITV applications, News on Demand applications, Electronic Program Guide (EPG), distance learning applications and background information for TV programs. Other results were also discovered. The following three questions were found important for all genres: 1) How can we make the program aesthetically appealing as possible? 2) How can we make the program visually compelling? 3) What type of an interface should the program have? Another result was that the following two questions that are central in film industry were not considered important for any of the ITV genres: 1) How can we have a three act structure in the program? 2) How can we arrange a happy ending for the program? The identified sets of questions will provide a good starting point for a person developing a program in the respective genre

User centered design of new and novel products : case digital television

Product development of innovative new products and applications like digital television is challenging. For new and novel products in general, there is no defined product direction given to the design team at the beginning of the project and there is no clear understanding of user requirements which results in constantly evolving product features. Yet there is a need for new or not-yet-existing hardware and software technologies but no earlier product versions or comparable existing products to benchmark against. User centered design aims to actively involve the users in product development in all phases of the new product design. The limits of user centered design and user research are that the users cannot address any particular future needs without prior experience or knowledge of the subject. Research methods such as usability testing are concerned about existing devices or prototypes but they do not tell directly which new technologies could help meet the users' future needs. New design methods which welcome users' active participation in gathering and interpreting the user data help to shift the point of interest from usability testing in the late phases of usability engineering life cycle to the early phases of product development. Digital television and the new interactive applications enable a transition in the user behavior from straightforward channel surfing to active application usage. This thesis concentrates on user centered design during the early phases of interactive application design for digital television. The aim of research was to find techniques to meet users' future needs and to provide examples of future product concepts. Several techniques were used: a user study based on 'Cultural probes' method, interviews, focus groups, design sessions, usability testing, and storytelling. The work documented here originates from the pre-digital television era in Finland between the years 1998-2003. The author has published her results in seven publications.reviewe