基于感知运动能量模型的MPEG-21数字项适配

最新的MPEG-21标准定义了一个统一的多媒体框架，其目标是使多媒体资源能在异构网络和终端上进行透明传输和得到充分利用。多媒体适配(Multimedia Adaptation)技术作为实现上述目标的关键技术得到了越来越多的研究。本文将感知运动能量模型与MPEG-21数字项适配框架相结合，研究和实现了基于感知运动能量的H．264／AVC视频丢帧适配技术。本文的研完工作有两个方面的优点：一方面，感知运动能量模型的使用将丢帧适配引起的运动抖动减至最小，保证了较高的用户视觉上的主观感知质量；另一方面，数据处理能力和资源受限的适配节点不需了解具体的H．264／AVC编码语法结构和编解码算法，就能方便地执行丢帧操作，实现了独立于媒体编码格式的视频适配机制，提高了多媒体适配系统的灵活性和可扩展性。

MPEG-21 Digital Item Adaptation by Applying Perceived Motion Energy to H. 264/AVC Video

The new MPEG-21 standard defines a multimedia framework to enable transparent and augmented use of multimedia resources across heterogeneous networks and devices used by different communities. In this paper, we in- corporate the Perceived Motion Energy (PME) Model into the proposed MPEG-21 Digital Item Adaptation Frame- work for frame dropping in H. 264 encoded video adaptation. There are two advantages of this work, one is the use of PME model to reduce the viewer's perceived motion jitter due to frame dropping to a minimum. The other is the adap- tation nodes can easily apply frame dropping operations without knowledge of detailed encoding syntax of H. 264 videos.