Usability Research On Video-on-demand Of Digital Television

With the development of the industry of digital and interactive technology, the interactive feature of digital television(DTV) can be fully expressed ,the digital television oriented interactive services become a tendency of household IT application. User can take part in the interactive services of digital television actively, such as interaction, information transmission and entertainment.Video-on-demand(VOD) is one of the important interactive appliances on DTV, which fully demonstrate interactive features of it. It provides video stream when user needs it without delay. But the user survey has showed a low degree of satisfaction to VOD, one of the reasons is the usability problems that the current VOD provide limited programmes, and there are some delays after demanding. The other reason, also most important, is the traditional evaluation method such as Heuristic evaluation,interview and observation, which have many limitations in practical applications, especially in the evaluation process of user interfaces. Such as when having usability test on product, it's based on the interactive between the tester and participant. The tester's expression, expectation, word and deed and all, will affect the participant and the action that they are taking part in. It will be more obviously when there are many testers. The result is we can't collect the accurate and objective user data, just existing some subjective when having the usability test.This thesis relies on the project of panel display of Guangdong Province, conducts research from the perspective of usability to build a complete usability evaluation and testing system which should be based on the theory of user-centered-design. And this thesis extends the traditional usability evaluation method by adding eye tracking technique. To evaluate the VOD usability by the combination of eye tracking technique and traditional usability evaluation. Which not only improve the accuracy and the objectivity of data, but also greatly reduce the subjective influence and error. This method contains the subjective one (interview and questionnaire scale) and the objective survey (eye movement scale in the laboratory) were combined together. The eye movement meter recorded the point of fixation, visual fixation position and visual time etc in the process of demanding movie,finding hotspot film. In addition to the survey of interview and questionnaire, we try to find what users need and then get the evaluation of VOD usability and propose the suggestions. On the background that the usability research area is almost a bland space, this paper's work will have many meanings both on theoretic study and practical application.