MPEG-1～MPEG-7的分析与评价

简要介绍MPEG-1～MPEG-7的发展过程;着重分析了MPEG-2标准及其编码策略和存在的缺陷,MPEG-4标准的新特色及其构成框架,MPEG-7标准构想所涉及的主要技术及难点等;详细介绍了MPEG系列标准的发展思路、技术原理及各自的应用领域,并展望了其对未来人类生活产生的的影响。     

一种基于MPEG-7的图像内容描述方案

图像内容检索是互联网应用的一个研究热点内容,如何准确地描述图像信息是多媒体信息检索必须要解决的问题。本文提出一种基于MPEG-7标准的图像内容的描述方案,可以有效地对图像内容进行描述。文章首先介绍了MPEG-7标准和描述方案,然后叙述基于MPEG-7的图像描述方案的技术与相关特征,最后给出一个具体的基于MPEG-7的图像描述方案的例子。     

MPEG-7的现状和发展

为了实现基于内容的多媒体信息检索，活动图像专家组MPEG制订了“多媒体内容描述接口”MPEG-7标准，与MPEG-1、2、4不同，MPEG-7不是一种新的编码标准，它独立于其它标准，运用MPEG-1、2、4中的工具和手段，同时为其服务。介绍了MPEG-7的研究背景、目标、研究内容以及应用领域。     

基于帧内区域的细粒度可扩展视频编码最优码率分配算法

MPEG-4 FGS是MPEG-4中精细可扩展性编码方法,由于采用帧8*8交织的位平面编码结构,无法支持帧内区域级的动态码率分配,不适合基于内容的增强和流化传输,针对MPEG-4 FGS这编码限制,本文根据MPEG-7的内容描述标准,提出了一种基于帧内区域的细粒度可扩展A-FGS编码,实现了实时的帧内区域流化编码,并就该编码提出了一种最优码率分配算法.利用帧内区域8*8宏块高位平面非零系数很少的特点,提出了动态码率分配算法,使在中等码率范围内编码效率提高了0.5dB左右.     

MPEG-7标准的目标及应用

活动图像专家组（ＭＰＥＧ）在完成ＭＰＥＧ－４第一版标准的制定工作后,又在着手制定ＭＰＥＧ－７标准。描述了ＭＰＥＧ－７标准的目标,并列举了ＭＰＥＧ－７工具将支持的若干应用。     

MPEG-2 spatial scalable coding and transport stream errorconcealment for satellite TV broadcasting using Ka-band

An effective MPEG-2 spatial scalable video codec is designed, and error concealment technique of associated transport stream is proposed. The spatial scalability can provide robust error resilience for Ka-band rain attenuation, as well as the co-existence of HDTV and SDTV systems. In MPEG-2, the spatial scalable encoder combines both spatial and temporal predictions. This paper proposes a near optimal spatial-temporal weighting analyzer to properly assign weights. Simulation shows that the proposed spatial scalable codec structure outperforms the performance of the other MPEG-2 codecs for TV broadcasting in Ka-band using satellites. We also propose a suitable error protection and concealment method for MPEG-2 transport stream. With the combination of scalable coding and error protection systems, the proposed system will achieve high link availability     

Everything you wanted to know about MPEG-7. 1

Audio-visual information must allow some degree of interpretation, which can be passed onto, or accessed by a device or a computer code. MPEG-7 aims to create a standard for describing these operational requirements. We provide an overview on the development, functionality, and applicability of MPEG-7. We present the role of MPEG-7 and outline ideas for using MPEG-7 technology based on examples of improved versions of existing applications as well as completely new ones. The MPEG standards preceding MPEG-7 have mainly addressed coded representation of audio-visual information. MPEG-7, on the other hand, focuses on the standardization of a common interface for describing multimedia materials (representing information about the content, but not the content itself (“the bits about the bits”)). In this context, MPEG-7 addresses aspects such as facilitating interoperability and globalization of data resources and flexibility of data management     

MPEG-2 spatial scalable coding and transport stream errorconcealment for satellite TV broadcasting using Ka-band

In this paper, an effective MPEG-2 spatial scalable video codec is designed, and an error concealment technique for the associated transport stream is proposed. The spatial scalability can provide robust error resilience for Ka-band rain attenuation, as well as the co-existence of HDTV and SDTV systems. In MPEG-2, the spatial scalable encoder combines both spatial and temporal predictions. This paper proposes a near optimal spatial-temporal weighting analyzer to properly assign weights. Simulation shows that the proposed spatial scalable codec structure outperforms the performance of the other MPEG-2 codecs for TV broadcasting in Ka-band using satellites. We also propose a suitable error protection and concealment method for the MPEG-2 transport stream. With the combination of scalable coding and error protection systems, the proposed system will achieve high link availability     

MPEG-7及其在互动电视系统中的应用

对即将出现并将会在未来的多媒体信息管理中居于重要地位的MPEG - 7做了介绍 ,MPEG -7的目的是要制定一种针对各类多媒体信息的描述标准 ,该描述与内容有关 ,并能够快速高效地搜索用户感兴趣的素材 ,根据MPEG - 7的这些特征 ,介绍了其在互动电视系统中的应用实例。     

基于SSE2的MPEG-4视频快速解码研究

离散余弦逆变换是MPEG-4视频纹理解码中运算时间开销最大的部分.本文在快速离散余弦逆变换算法的基础上,引入针对多媒体数据流的SSE2并行计算技术.在保证图像质量的前提下大幅度提高了软件的解码速度.实验结果表明,该方法能有效地降低MPEG-4视频解码的时间开销,适合于NC环境下的视频分发应用.     

多媒体系列标准MPEG的发展研究

通过对MPEG－1到MPEG－21发展过程的分析，详细论述了MPEG系列标准的技术原理及应用领域；并对MPEG－4，MPEG－7和MPEG－21标准的主要技术进行了重点研究。     

基于内容的图像检索与MPEG-7

随着数字图像信息的高速膨胀与增加,基于内容的图像检索技术已经成为了一个被广泛关注的研究领域.与此同时,国际标准MPEG-7的制定,极大的促进了这一领域的发展.本文将主要对基于内容的图像检索的研究现状以及关键技术进行了分析,介绍了MPEG-7标准的相关内容,并在此基础上提出一种基于MPEG-7标准的图像检索系统模型.     

Improved MPEG-4 still texture image coding under noisy environment

This paper describes the performance of the MPEG-4 still texture image codec in coding noisy images. As will be shown, when using the MPEG-4 still texture image codec to compress a noisy image, increasing the compression rate does not necessarily imply reducing the peak-signal-to-noise ratio (PSNR) of the decoded image. An optimal operating point having the highest PSNR can be obtained within the low bit rate region. Nevertheless, the visual quality of the decoded noisy image at this optimal operating point is greatly degraded by the so-called "cross" shape artifact. In this paper, we analyze the reason for the existence of the optimal operating point and the "cross" shape artifact when using the MPEG-4 still texture image codec to compress noisy images. We then propose an adaptive thresholding technique to remove the "cross" shape artifact of the decoded images. It requires only a slight modification to the quantization process of the traditional MPEG-4 encoder while the decoder remains unchanged. Finally, an analytical study is performed for the selection and validation of the threshold value used in the adaptive thresholding technique. It is shown that, the visual quality and PSNR of the decoded images are much improved by using the proposed technique comparing with the traditional MPEG-4 still texture image codec in coding noisy images.     

3D Model compression using Connectivity-Guided Adaptive Wavelet Transform built into 2D SPIHT

Connectivity-Guided Adaptive Wavelet Transform based mesh compression framework is proposed. The transformation uses the connectivity information of the 3D model to exploit the inter-pixel correlations. Orthographic projection is used for converting the 3D mesh into a 2D image-like representation. The proposed conversion method does not change the connectivity among the vertices of the 3D model. There is a correlation between the pixels of the composed image due to the connectivity of the 3D mesh. The proposed wavelet transform uses an adaptive predictor that exploits the connectivity information of the 3D model. Known image compression tools cannot take advantage of the correlations between the samples. The wavelet transformed data is then encoded using a zero-tree wavelet based method. Since the encoder creates a hierarchical bitstream, the proposed technique is a progressive mesh compression technique. Experimental results show that the proposed method has a better rate distortion performance than MPEG-3DGC/MPEG-4 mesh coder.     

图象压缩技术及其应用

本文介绍当前图象数据压缩技术的研究与应用，对于静态图象重点讨论以人眼视觉感知特性为指导的压缩技术，对于动态图象压缩技术，着重介绍ＭＰＥＧ－２及正在发展中的ＭＰＥＧ－４的一些目标和特点，以及基于模型的编码方法，文中还简介了图象压缩技术的应用和产品研制情况。     

基于MPEG-7的多媒体内容描述方法研究

如何准确地描述多媒体信息是多媒体信息检索必须要解决的问题。文中介绍了MPEG-7标准多媒体内容的描述工具,然后从结构和内容两个方面研究MPEG-7描述多媒体内容的方法,并给出了实际的例子。     

用于音乐的MPEG7和符合MPEG7的音乐

ＭＰＥＧ－７,即多媒体内容描述接口（Ｍｕｌｔｉｍｅｄｉａ Ｃｏｎｔｅｎｔ Ｄｅｓｃｒｉｐｔｉｏｎ Ｉｎｔｅｒｆａｃｅ）致力于对视听材料描述进行标准化,以实现通用的索引、检索、过滤、控制以及由量的元数据所支持的其他操作。文章给出了ＭＰＥＧ－７的概念的一个综述,并提供了一怎样将目前的实际结合进ＭＰＥＧ－７框架中的例子,阐述了对标准的可能发展方向和解决方案的一些想法。