Vintage radio interface

Shot change detection is a main technique for automatic temporal segmentation of video, which requires adaptive adjustment of thresholds and real-time operation in actual applications. To date, few researches have been conducted on real-time shot change detection to be applied to hardware terminals with low performance such as PMPs (portable media player) and cellular phones. In this paper, we propose an adaptive real-time shot change detection algorithm and implement it on an actual PMP. The proposed algorithm consists of the following elements: sub-sampling, weighting variance, and adaptive thresholds. Our experiments obtained the detection rate of about 94.4% in overall accuracy, demonstrating a higher detection rate and a computational amount 1/256 less than the conventional algorithms which have optimal fixed thresholds adjusted by humans for each video. We verified the real-time operation of shot change detection by implementing our algorithm on the PMP of Homecast, a PMP company. The proposed algorithm will be helpful in searching video data on portable media players such as PMPs and cellular phones.

For most portable media player (PMP), the demands for large storage space and longer working time usually can not be satisfied at the same time. In this paper, a low power wireless LAN based PMP called WiPMP is proposed. WiPMP is basically a diskless PMP. Instead, it can retrieve a large number of multimedia data from a remote storage device wirelessly. A prototype of WiPMP has been realized on an Intel Xscale embedded platform with embedded Linux as the operating system. A systematic power measurement and analysis method is used in this paper to evaluate the prototype from the perspective of power consumption. The result shows that WiPMP does consume less power and is able to access much more multimedia data than the hard disk based PMP.

Shot change detection is the main technique for automatic temporal segmentation of video. Until now, there were little research reports about real-time shot change detection for applying to hardware terminals with low performance such as PMPs (Portable Multimedia Player) and cellular phones. In this paper, we propose an adaptive real-time shot change detection algorithm using sub-sampling, weighting variance, and an adaptive threshold. We use weighting variance of frame difference for dividing feature extraction at a changed frame. We set an adaptive threshold using the average of variance from the next one of a last shot change frame to the previous one of a current frame. In the experiments, we obtained the detection rate of about 94.4% in overall accuracy. We verified real-time operation of shot change detection by implementing our algorithm on the TVUS HM-900 PMP from the company of Homecast. Therefore, our proposing algorithm will be helpful in searching video data on portable media player such as PMPs and cellular phones.

PodWalks are a new kind of Podcasts where virtual narrators guide users through real-world spaces. PodWalks can increase a user's appreciation of real spaces by connecting them to audio tours stored on portable media players that can be listened to any time and anywhere without using mobile telecommunication services. One disadvantage of PodWalks is that it can be difficult for listeners to synchronize their locations with the location that the narrator is describing and, as a result, listeners become disoriented. To solve this problem we propose a new framework—maPodWalks—as an extension to PodWalks which provides maps that are synchronized to the narrations on mobile media players. By forming linkages between virtual and real-world experiences, maPodWalks help users develop mental maps of places of interest. In this paper, we discuss the characteristics of maPodWalks and present a prototype maPodWalk Maker that allows users to easily create geocoded audio tours. The results of system tests comparing the performance of PodWalks and maPodWalks are reported as well.

A portable media player is a consumer electronics device that is capable of storing and playing digital media such as audio, image, video, and etc. NAND flash memory has been widely deployed as a storage medium for these portable media players because of its small size, light weight and low power consumption. However, due to distinct characteristics of NAND flash memory such as no in-place update, asymmetric operation unit and speed, conventional disk-based buffer replacement scheme may not yield good performance on flash memory-based storage systems. In this work, we propose a novel buffer replacement scheme considering the features of metadata as well as multimedia data for portable media players. Our proposed scheme classifies the pages into a long sequential reference set and a short sequential reference set by checking the sequential continuity of pages in the buffer. And then, it mainly evicts long sequential reference sets first from the buffer and keeps short sequential reference sets in the buffer as long as possible to improve the hit ratio. By this strategy, we can efficiently reduce the number of write and erase operations to the flash memory when storing and playing digital media. Through various experiments, we show that our proposed scheme yields better performance than its related work <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> .

Usability testing has gained a rather stable status as a method for usability evaluation even though it has both low reliability and validity. The sources of result variance are well acknowledged among researchers and practitioners. However, the validity problem has not been explicated or exemplified although it is frequently discussed in the literature how the results of usability tests should be interpreted and to what extent results are generalizable. We employ Activity Theory and a case example to argue that the validity problem is mainly caused by the fact that what we are testing are artifacts and what people are using in their real life activities are tools and these two entities are qualitatively different. Basing on our analysis, the effects of the reliability and validity problems on the application of usability testing and its role as one of the tools in the design process are discussed.

This paper assesses the implementation of the framework for building new Distinctive Features and design mathematics games. We explain how to design a typical mathematics game according to the learning needs of elementary school students. Next, we explain how to build new Distinctive features that are unique to students' needs and can be run in math games. We explain the importance of constructing mathematics game features and designs that suit the characteristics of primary school students. We conclude that the selection of distinctive features and game design according to students' needs are the most important aspects in building an interesting mathematics learning experience. This conclusion was obtained from the results of usability tests on elementary school students. This paper has broad implications in the development of elementary school games.

Pressure from customers, the trade press, and the competition is causing companies to focus more on delivering usable products. But even when the commitment is there, companies still find it difficult to get their developers to believe in the results of usability tests and to make improvements based on them. The authors report on what Lotus has done to bring developers closer to the process, describing tools, techniques, and concepts to optimize user interfaces. They have found four approaches particularly valuable in getting developers and other members of the product team involved in usability testing: informal setups, sit-in sessions, usability nights, and videotapes. Their experience shows that these methods are more effective than conventional practices, in which developers merely receive reports of key problems from the test sessions. >

Projet MIRAS : robot d’assistance à la déambulation avec interaction multimodale

Orientation software produced today is generally designed for the navigation of cars. However, the navigation needs of pedestrians are different from those of drivers. The aim of this study is the design of a cartographic interface that supports the navigation of pedestrians in unfamiliar areas using landmarks and evaluation of this geo-mobile application by usability testing. In this study, an approach to landmark orientation based on the Voronoi diagram is proposed. Furthermore, the developed mobile application that uses this approach is explained in detail. The results of user tests are also given.

Electromagnetic interference with pacemakers caused by portable media players

The implantable loop recorder has been shown to be a cost-effective tool for diagnosis of intermittent cardiovascular symptoms such as syncope and palpitations. Electromagnetic interference in these recorders may be caused by commonly encountered electronic devices such as antitheft electronic surveillance systems and magnetic resonance imaging cameras. In this report, we describe interference in two patients with implantable loop recorders from a portable digital media player.

In this paper we present a general approach to the automatic content-based organization and visualization of large digital music collections. The general methodology consists in extracting musically and perceptually relevant patterns (‘features’) from the given audio recordings (e.g., mp3 files), using topology-preserving data projection methods to map the entire music collection onto two-dimensional visualization planes (possibly in a hierarchical fashion), and using a new display metaphor (the ‘Islands of Music’) to display the inherent structure of the music collection to the user. It is shown how arbitrary meta-data can be integrated into the visualization process, and how similarity according to different viewpoints can be defined and exploited. The basic methodology is briefly described, three prototype systems are presented, and a general discussion of the practical application possibilities of such technologies is offered.

A case study on migrating large digital collections into a consolidated repository

We are witnessing an explosion of digital information, some of it in unstructured repositories, some in still primitive digital libraries. This trend is certain to accelerate as the National Information Infrastructure (NII) and Global Information Infrastructure (GII) become a reality. Several digital library projects in the USA and abroad are in progress, with the goal of developing the enabling technologies for creating a single, integrated and “universal” library, composed of the large numbers of individual heterogeneous repositories. These include materials in personal information collections, collections in conventional libraries, and large data collections shared by scientists, engineers and other researchers. Six US institutions received funding for Digital Library Initiatives in the fall of 1994. In addition, the Library of Congress (LC) has a National Digital Library Project under way that is funded, in part, by private corporations and foundations to make some of its large text and image collections accessible via computer networks. Focuses on projects at Carnegie Mellon University, the University of Illinois and the Library of Congress, including how these initiatives will affect the way image and text archives are organized as we enter the next century, and their implications for the international community. Addresses the following issues: how can we encourage global intellectual access and p articipation by our citizenry? How does one locate (“navigate”) information of interest in a very large, distributed and possibly disconnected collection of libraries and archives around the world? And how can we protect the intellectual property of authors and publishers and detect violations in this new information environment?