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101.
102.
IPMulticast在多媒体远程安全监控系统中的应用 总被引:1,自引:1,他引:0
介绍了IPMulticast技术在多媒体远程安全监控系统中的应用,给出了整个监控系统的功能模块和系统框图,从分析整个多媒体远程安全监控系统中所需传输的数据类型出发,讨论了IPMulticast技术在整个监控系统中的应用,最后给出了相关的C 程序实现的源代码。 相似文献
103.
104.
多媒体信息网络实时传输的应用研究 总被引:2,自引:1,他引:1
论述了基于MPEG-I的编解码国际标准和TCP/IP网络协议,多媒体信息在网络环境下的实时传输,并对视频编解码技术和网络编程技术进行了探讨。给出了一个多媒体网络实时监控系统的实例,介绍了它的功能、体系结构和核心模块的设计与实现。 相似文献
105.
Mohamed Ahmed Hamid Harroud Roger Impey Ahmed Karmouch 《Multimedia Tools and Applications》2007,34(3):299-315
In this paper, we aim to provide adaptive multimedia services especially video ones to end-users in an efficient and secure
manner. Users moving outside the office should be able to maintain an office-like environment at their current locations.
First, the agents within our proposed architecture negotiate the different communication and interaction factors autonomously
and dynamically. Moreover, we needed to develop a user agent in addition to service and system agents that could negotiate
the requirements and capabilities at run time to furnish best possible service results. Thus we designed and integrated a
video indexing and key framing service within our overall agent-based architecture. We integrated this video indexing and
content-based analysis service to adapt the video content according to run time conditions. We designed a video XML schema
to validate the media content out of this multimedia service according to specific requirements and features, as we will describe
later.
相似文献
Ahmed KarmouchEmail: |
106.
鲁松 《数字社区&智能家居》2007,1(5):1405-1407
利用"方正奥思"制作的综合型多媒体课件,可以实现学生自我测试试题的随机抽取,并进行自动判分;自动记录学生学习进度、测试成绩;实现教师对课件中教学内容或测试试题的增删、修改管理等功能.本文将对全套设计给出思路和方法. 相似文献
107.
The use of collaborative virtual environments in e-learning is one of the most promising uses of virtual reality technology. While much research has been done in the area of networked virtual environments corresponding to the sharing of events, very little research has been done on specific services and functionality. However both the requirements and the kind of the offered services affect significantly the design of a system. In this paper we present the design and implementation of a platform suitable for educational virtual environments, which are collaborative virtual environments aiming at offering collaborative e-learning services to the users. Apart from the platform itself, we present the technological choices, and a new method for sharing virtual environments. Furthermore, we present an e-learning environment to support e-learning services using collaborative virtual environments from both the technical and functional point of view, along with the end-user evaluation results.
相似文献
C. BourasEmail: |
108.
As music can be represented symbolically, most of the existing methods extend some string matching algorithms to retrieve musical patterns in a music database. However, not all retrieved patterns are perceptually significant because some of them are, in fact, inaudible. Music is perceived in groupings of musical notes called streams. The process of grouping musical notes into streams is called stream segregation. Stream-crossing musical patterns are perceptually insignificant and should be pruned from the retrieval results. This can be done if all musical notes in a music database are segregated into streams and musical patterns are retrieved from the streams. Findings in auditory psychology are utilized in this paper, in which stream segregation is modelled as a clustering process and an adapted single-link clustering algorithm is proposed. Supported by experiments on real music data, streams are identified by the proposed algorithm with considerable accuracy.
相似文献
Man Hon WongEmail: |
109.
On Similarity Measures for Multimedia Database Applications 总被引:1,自引:1,他引:0
A multimedia database query consists of a set of fuzzy and boolean (or crisp) predicates, constants, variables, and conjunction,
disjunction, and negation operators. The fuzzy predicates are evaluated based on different media criteria, such as color,
shape, layout, keyword. Since media-based evaluation yields similarity values, results to such a query is defined as an ordered
set. Since many multimedia applications require partial matches, query results also include tuples which do not satisfy all
predicates. Hence, any fuzzy semantics which extends the boolean semantics of conjunction in a straight forward manner may
not be desirable for multimedia databases. In this paper, we focus on the problem of ‘given a multimedia query which consists of multiple fuzzy and crisp predicates, how to provide the user with a meaningful
overall ranking.’ More specifically, we study the problem of merging similarity values in queries with multiple fuzzy predicates. We describe
the essential multimedia retrieval semantics, compare these with the known approaches, and propose a semantics which captures
the retrieval requirements in multimedia databases.
Received 13 August 1999 / Revised 13 May 2000 / Accepted in revised form 26 July 2000 相似文献
110.
Adaptive e-learning materials can help teachers to educate heterogeneous student groups. This study provides empirical data about the way academic students differ in their learning when using adaptive e-learning materials. Ninety-four students participated in the study. We determined characteristics in a heterogeneous student group by collecting demographic data and measuring motivation and prior knowledge. We also measured the learning paths students followed and learning strategies they used when working with adaptive e-learning material in a molecular biology course. We then combined these data to study if and how student characteristics relate to the learning paths and strategies they used. We observed that students did follow different learning paths. Gender did not have an effect, but (mainly Dutch) BSc students differed from (international) MSc students in the intrinsic motivation they had and the learning paths and strategies they followed when using the adaptive e-learning material. 相似文献