QRTP: A Middleware for Broadband Networks

Broadband networks, such as those based on Asynchronous Transfer Mode (ATM), provide large bandwidth and multiple services. An essential application area for broadband networks is multimedia systems. The development of multimedia applications, however, is currently lagging behind the advances in the network technology. Our approach to the problem of more effectively developing multimedia applications is to provide developers with a middleware that encompasses a set of broadband-specific services needed by multimedia applications, for instance virtual connection setup, bandwidth reservation and session synchronization. Our middleware, called the Queen's Real-time Transport Protocol (QRTP), is based on the Real-time Transport Protocol standard from the Internet Engineering Task Force. The paper discuses the design, implementation and evaluation of the QRTP middleware.     

mStar: enabling collaborative applications on the Internet

Distributed, real-time multimedia applications on the Internet permit users to cooperate in new and more interesting ways for collaborative teamwork and net-based learning. The mStar environment features an agent-based architecture, implemented in Java, which preserves compatibility with the dominant Mbone paradigm for IP multicast. The shared software environment provides an integrated solution for generating, presenting, scoring, and editing media in collaborative applications. In particular, mStar supports developers in creating distributed, real-time multimedia software applications such as e-meetings. mStar enhances both distance education and collaborative teamwork by presenting a uniform user interface for real-time audio and video, shared whiteboard, char, voting, and distributed Web-based presentations. The system also supports on-demand recording and session playback     

Leveraging Java applets: toward collaboration transparency in Java

Widespread use of the Internet is giving rise to the need for collaborative applications that link users at remote sites. Many toolkits support the development of collaboration-aware applications, those developed specifically for cooperative work by multiple users. Another approach is collaboration transparency, the collaborative use of applications originally developed for a single user. When the runtime environment supports collaboration transparency, an application programmer need not write new code to make an application collaborative. Thus, collaboration transparency leverages the existing base of single user applications by extending them to collaborative use. We review options for providing collaboration transparency. We also discuss how collaboration transparency can be incorporated into Sun Microsystems' Java, the most widely used vehicle for developing interactive World Wide Web applications     

A coordination framework and architecture for internet groupware

We discuss a group coordination architecture to support Internet-wide distributed collaboration, in particular for WWW-based distance education. With the current surge in e-commerce and Web-centric information exchange among users, the need for systems offering better telepresence and interaction capabilities becomes tangible. Group coordination in distributed systems and networked multimedia systems has many faces manifested in a variety of user interfaces and network protocols. However, to date no general methodology exists for engineering group coordination protocols to streamline the deployment of remote learning and collaboration environments. The objective of this article is to identify the key elements of a general group coordination framework, complementing existing group membership and multicast dissemination models, and to set the cornerstones for a coordination architecture which may be used to leverage the rapid development of group-oriented distributed collaborative applications in the Internet, for example for distance education, distributed scientific simulation and visualization, or similar applications.     

Collaborative telemedicine for interactive multiuser segmentation of volumetric medical images

Telemedicine has evolved rapidly in recent years to enable unprecedented access to digital medical data, such as with networked image distribution/sharing and online (distant) collaborative diagnosis, largely due to the advances in telecommunication and multimedia technologies. However, interactive collaboration systems which control editing of an object among multiple users are often limited to a simple “locking” mechanism based on a conventional client/server architecture, where only one user edits the object which is located in a specific server, while all other users become viewers. Such systems fail to provide the needs of a modern day telemedicine applications that demand simultaneous editing of the medical data distributed in diverse local sites. In this study, we introduce a novel system for telemedicine applications, with its application to an interactive segmentation of volumetric medical images. We innovate by proposing a collaborative mechanism with a scalable data sharing architecture which makes users interactively edit on a single shared image scattered in local sites, thus enabling collaborative editing for, e.g., collaborative diagnosis, teaching, and training. We demonstrate our collaborative telemedicine mechanism with a prototype image editing system developed and evaluated with a user case study. Our result suggests that the ability for collaborative editing in a telemedicine context can be of great benefit and hold promising potential for further research.     

一种共享主存二维SIMD结构资源分配算法的改进与实现

共享主存二维SIMD结构已经广泛应用于多媒体处理加速部件,其数据并行性可以大大提高处理器的运算能力。目前,已有一些针对共享主存二维SIMD结构编译优化方面的研究,这些编译优化技术能有效地提高各种多媒体应用程序的加速比。但是,分析可知,这些优化方法的平均资源利用率只有约50％。本文基于对多媒体应用程序在共享主存二维 维SIMD结构上的执行过程分析,根据原有算法并适当修改经典图着色寄存器分配算法,提出了一种改进的资源分的目的。实验结果说明,该算法的改进对于大部分多媒体应用程序的性能有显著的提高。     

A comparison of multimedia application development platforms towards the object web

In this paper, a complete scenario for the provision of interactive multimedia services over the Internet is considered, exploiting emerging software methodologies that implement different aspects of what is called the object web.Initially, web-application design considerations over the years are presented, in parallel to the evolution of the World Wide Web. Then, the study focuses on a distributed multimedia application aiming to deliver, over the Internet, information on children's TV programs and co-productions. Two different object oriented implementation models are described, the HTTP/Microsoft's active server pages (ASP) approach and the Java/common object request broker architecture (CORBA) approach. Finally, experimental results comparing the two implementation models are presented and the advantages gained from the latter are highlighted.     

The IP multimedia domain: service architecture for the delivery of voice, data, and next generation multimedia applications

The IP Multimedia Subsystem (IMS) is defined by the 3 ^rd Generation Partnership Project (3GPP) as a new core network domain. IMS provides a service control platform that allows creation of new multimedia and multi-session applications utilizing wireless and wireline transport capabilities. In this paper we will cover the concepts and standards defining IMS and review the network architecture from a mobile perspective. We will see how IMS interacts with the Packet Switched Domain (e.g. Wireless LAN, GPRS, and UMTS networks), the Internet, and application services. Then we will examine the key IMS capabilities and show how they can be combined to create new mobile IP services. Finally, we present a software architecture, which is enabled by IMS and allows development of unique applications (with multimedia/multi-session functionality, single/multi-user, service to user). The software architecture is illustrated by an example of a prototype application. This work was done when the author was with Siemens Communications Inc., Boca Raton, FL     

The IP multimedia domain: service architecture for the delivery of voice, data, and next generation multimedia applications

The IP Multimedia Subsystem (IMS) is defined by the 3^rd Generation Partnership Project (3GPP) as a new core network domain. IMS provides a service control platform that allows creation of new multimedia and multi-session applications utilizing wireless and wireline transport capabilities. In this paper we will cover the concepts and standards defining IMS and review the network architecture from a mobile perspective. We will see how IMS interacts with the Packet Switched Domain (e.g. Wireless LAN, GPRS, and UMTS networks), the Internet, and application services. Then we will examine the key IMS capabilities and show how they can be combined to create new mobile IP services. Finally, we present a software architecture, which is enabled by IMS and allows development of unique applications (with multimedia/multi-session functionality, single/multi-user, service to user). The software architecture is illustrated by an example of a prototype application. This work was done when the author was with Siemens Communications Inc., Boca Raton, FL     

Interactive multi-user video retrieval systems

In this paper we present two interactive multi-user systems for video search and browsing. The first is composed by web applications which allows multiuser interaction in a distributed environment; such applications are based on the Rich Internet Application paradigm, designed to obtain the levels of responsiveness and interactivity typical of a desktop application. The second system implements a multi-user collaborative application within a single location, exploiting multi-touch devices. Both systems use the same backend, based on a service oriented architecture (SOA) that provides services for automatic and manual annotation, and an ontology-based video search and browsing engine. Ontology-based browsing let users to inspect the content of video collections; user queries are expanded through ontology reasoning. User-centered field trials of the systems, conducted to assess the user experience and satisfaction, have shown that the approach followed to design these interfaces is extremely appreciated by professional archivists and people working on multimedia.     

Tools for transparent synchronous collaborative environments

Synchronous collaborative environments can provide an identical visual and operable working area among geographically separated participants. There are two basic approaches for providing a shared workspace. They are collaborative-aware approach and collaborative-unaware approach. Since the second approach allows single-user applications to be reused, most users choose to use it. Our work is based on the collaborative-unaware environment. This paper describes the design and implementation of some transparent synchronous collaborative tools. They are: (1) the latecomer support for Java applications, Java applets and JMF players (2) the client synchronization to minimize data transmission latency and (3) the lightweight multi-session support to let different collaboration groups work at the same time. These tools optimize existing transparent synchronous collaboration systems and make them more realistic, more complete and more generic.

基于Internet的多用户共享虚拟环境框架的研究

多用户共享虚拟环境是指网络化的协同虚拟现实系统，在该环境中多个用户之间通过各自的三维图形表示实现在虚拟环境中的多人感知，用户之间的交互以及对虚拟对象的协同操纵，在综合分析现有系统以及Internet的开放性标准化需求基础上，提出了一种基于Internet的多用户共享虚拟环境解决方案，即多用户共享虚拟环境框架（multi-user shared virtual envitonment framework,MSVEF)，该框架描述了多用户虚拟环境的体系结构，定义了基于XML的相关交互协议，通过在原型系统中的初步应用，证明该框架可以支持不同网络平台的用户在同一个虚拟场景中的再现与交互。     

A workflow management system based on intelligent collaborative objects

This paper describes an architecture for workflow management systems based on Workflow Intelligent Business Objects (WIBOs). The design of WIBOs is based on principles of intelligence, autonomy, collaboration and co-operation. Using WIBOs that carry out tasks on users’ behalf, it is possible to build workflow systems that bring further improvements in process automation and dynamic management, and achieve dynamic (re)allocation of resources to Actors. A WIBO prototype architecture has been implemented using Java. A Java Remote Method Invocation (RMI) has been used to enable WIBOs to communicate over an Intranet or Internet.     

InCloud: a cloud-based middleware for vehicular infotainment systems

Smart vehicles form pervasive environment to enhance user experience through multimedia enabled infotainment systems. In order to realize effective infotainment system for vehicles, we need to have context-aware applications that use latest (live) information for enhanced user experience. Such latest information is abundantly available on the Internet due to explosive growth of Web 3.0, which can be accessed through wireless communication infrastructures such as VANETs and LTE. In this paper we propose a cloud-based middleware framework, InCloud, for vehicular infotainment application development. The proposed framework follows service oriented architecture in which data filtering and fusion functionalities are delegated to the cloud. Data filtering and fusion reduce the data flow over wireless link. Furthermore, because most of the processing is done on the cloud, the client becomes lightweight and loosely coupled with Internet resources and underlying platforms in vehicles. We also propose a class-based fusion method for combining information from multiple resources on the Internet. The efficacy of the proposed framework is validated by developing three infotainment applications for vehicles: context-aware music, news, and an enhanced Direction (eDirection) application.

     

多媒体会议系统集成框架的研究和实现

为了解决各种异构多媒体会议系统之间难以互通的问题，结合基于应用层组播技术与代理机制设计和实现了能够让各个异构多媒体会议系统相互协同的集成框架。应用代理机制把各个异构系统封装成可以相互通信的协同群组，在Internet物理拓扑基础上部署一个连接各个协同群组的称为覆盖网的虚拟拓扑结构，以此为基础设施在各协同组之间构建数据组播树，实现数据的高效分发，提供各种协同服务和异构接入服务把各种异构系统封装成相互可以通信的协同工作群组。     

Building KidPad: an application for children's collaborative storytelling

Collaborating in small groups can be beneficial to children's learning and socializing. However, there is currently little computer support for children's collaborative activities. This was our motivation for building KidPad, a collaborative storytelling tool for children. KidPad provides children with drawing, typing, and hyperlinking capabilities in a large, two-dimensional canvas. It supports collaboration by accepting input from multiple mice. In building KidPad, we developed solutions to problems common to all single-display groupware applications for children: using an intuitive user interface metaphor that can support collaboration, and obtaining input from multiple devices. We addressed the need for an appropriate user interface metaphor by using the local tools metaphor. In developing the concept of local tools we learned about the importance of addressing the issue of global modes. Our solution for obtaining input from multiple devices was MID, an architecture written in Java. In building MID, we learned about the importance of building flexible architectures that can support a wide range of applications and devices in a consistent manner, and that are easy to extend and use by programmers. This paper describes our work on local tools and MID in the context of building KidPad, and aims to provide developers with valuable insights into how to develop collaborative applications for children. Copyright © 2004 John Wiley & Sons, Ltd.     

Galoan: a multi-agent approach to herd cows

This paper describes the team Galoan (it is a local Persian name that means shepherd), one of the participants in the Multi-Agent Programming Contest 2010. We present the agents’ architecture as well as the team strategies and the coordination and cooperation approaches. Our system was developed using the blackboard style and was implemented in Java. In our approach each agent stores its perception in a shared world model which is called blackboard. Coordination has been implemented through a supervisor. The supervisor uses the stored information in the blackboard and coordinates the agents to achieve a goal. Finally, we outline our observations and discuss the performance of our team.     

ID-Services: an RFID middleware architecture for mobile applications

The use of RFID middleware to support application development for and integration of RFID hardware into information systems has become quite common in RFID applications where reader devices remain stationary, which currently represents the largest part of all RFID applications in use. Another field for applying RFID technology which is offering a huge set of novel possibilities and applications are mobile applications, where readers are no longer fixed. In order to address the specific issues of mobile RFID-enabled applications and to support developers in rapid application development, we present ID-Services, an architecture for an RFID middleware that is designed to support mobile applications. The ID-Services approach has been used to implement MoVIS (Mobile Visitor Information System), a mobile application which allows museum visitors to request individually adapted multimedia information about exhibits in an intuitive way.     

建立分布式多媒体系统的体系结构参考模型

分布式多媒体系统具有广阔的应用前景。但由于缺乏一致的体系结构，其研究和开发均受到了很大的限制。本文首先给出分布式多媒体系统的资源配置模型和一般功能需求，引入虚拟设备、虚拟连接、ＱｏＳ等概念，最后描述了我们所使用的分布式多媒体系统体系结构参考模型。该模型对理解分布式多媒体系统的特点和工作原理亦有相当帮助。