Unequal Forced-Intra-Refresh for robust video streaming

INTRODUCTION In the encoding or transcoding of video stream- ing, intra refresh is introduced as a non-normative error-resilience tool. Although the intra-refresh schemes based on the rate-distortion optimization (C?té et al., 2000; Stockhammer et al., 2002) are superior to the early heuristic intra-refresh strategies, these new schemes cannot yet accurately estimate the video distortion due to time-varying packet losses, and usually ignore the inter-frame error-propagation effect. Chiou…     

医学影像学人才培养模式探讨

在确定"一方向、一重点、二基础"的培养模式的前提下,通过调整教学计划,优化教学内容,改革教学方法等手段,达到为新世纪培养个有中国特色的医学影像学专门人才的目标。     

Learning, change, and the utopia of play

This article looks at some of the rhetoric surrounding video games and other forms of interactive software as additions or alternatives to school curricula. It focuses particularly on the need to articulate ways to “read” videogames in order to achieve significant cultural impact. Noting that reading, even as metaphor, tends to invoke inappropriate assumptions about writing and authorship, the article argues for a less backward-looking approach to newer forms.     

Video gaming as digital media,play, and family routine: implications for understanding video gaming and learning in family contexts

While a number of studies have investigated learning associated with video gaming in out-of-school settings, only recently have researchers begun to explore gaming and learning in the contexts of home and family life. This paper discusses three different frameworks within which we can situate video games and learning at home: (a) video gaming as digital media, (b) video gaming as play, and (c) video gaming as family routine. Each framework brings different issues related to learning into focus, and contributes new insights into the role gaming plays in the lives of children, adults, and families as a whole.     

Efficient video downscaling transcoder from MPEG-2 to H.264

The new H.264 video coding standard achieves significantly higher compression performance than MPEG-2. As the MPEG-2 is popular in digital TV, DVD, etc., bandwidth or memory space can be saved by transcoding those streams into H.264 in these applications. Unfortunately, the huge complexity keeps transcoding from being widely used in practical applications. This paper proposes an efficient transcoding architecture with a smart downscaling decoder and a fast mode decision algorithm. Using the proposed architecture, huge buffering memory space is saved and the transcoding complexity is reduced. Performance of the proposed fast mode decision algorithm is validated by experiments.     

基于运动特征的视频检索技术

运动特征是描述视频内容的一种重要信息，本文介绍了一个基于运动特征的视频检索系统。提出了描述全局摄像机运动及特征提取方法。     

视频通信中的差错掩盖技术

本文讨论了视频通信中压缩视频的关键数据(纹理信息，编码模式I、P、B，以及运动向量MV)的恢复方法，对典型的差错掩盖技术及掩盖方法进行详细描述，并对其适应环境作了简要分析。     

Equation based rate control scheme for video streaming over wireless channels with link level ARQ

INTRODUCTION Video streaming applications generally require continuous high bandwidth guarantees as well as stringent bounds on delays and jitters (Shen et al., 2004; Hassan and Krunz, 2004). Providing video streaming with acceptable quality degradation over wireless channels is fraught with challenges due to the adverse influence of bandwidth limitation, time variation, high error rate, and so on (Etoh and Yo- shimura, 2005; Shen et al., 2004; Chen and Zakhor, 2004; Hassan and Krunz, …     

Using video clubs to develop teachers’ thinking and practice in oral feedback and dialogic teaching

ABSTRACT

The authors report outcomes of an evaluation of a ‘video club’ intervention to improve the feedback and dialogic teaching practice of 91 teachers from 11 primary schools in England. Participating teachers worked collaboratively in a sequence of six video clubs over a six-month period. To understand teacher engagement they examine videos of video club meetings; online platform use metrics; surveys; selected videos of classroom practice; focus groups; and interviews. They evaluate change in teachers’ thinking and practice using survey results for participants compared to a comparison group of non-participating teachers at the intervention schools. The survey includes a new instrument for gathering evidence of teachers’ thinking and practice in feedback. The results suggested changes in thinking and practice for teachers who self-reported as engaging highly with the intervention. They conclude by discussing the potential of video technology within professional development and the challenges of researching changes in thinking and practice.