【作者】 高燕萍；

【导师】 赵旦峰；

【作者基本信息】 哈尔滨工程大学 ， 通信与信息系统， 2002， 硕士

【摘要】 随着数字视频广播(DVB)和高清晰度电视(HDTV)技术及业务的发展，MPEG2(ISO／IEC 13818)运动图像及其伴音编码标准在数字音视频领域得到了广泛的应用。节目源缺乏是开播标准清晰度电视(SDTV)和高清晰度电视面临的一个主要困难，也是DVB、视频点播(VOD)等系统取得成功的重要因素。本课题的研究旨在解决这一问题，主要完成了以下几项研究工作： 1)视频信息从MPEG2 PS格式至MPEG2 TS格式的转换。 2)针对目前机顶盒不能解码的NTSC制式Dolby AC3编码算法音频信息，转换成MPEG1／2 LayerⅡ编码，并打成满足MPEG2 TS语法的信息包。 3)提出了能使音视频达到良好同步的继承性时间标签打入算法 本文详细介绍了MPEG2标准的语法，讨论了MPEG2系统的时间模型从而指出视音频处理中的关键，对PCR的处理进行了详细的分析，提出了新的视、音频同步算法。 本课题实现了为VOD系统节目采编工作站提供丰富的节目源。采用高清晰度的DVD盘片作为节目的来源，将DVD中的视频、音频节目内容转换成符合DVB传送标准的MPEG2 TS格式，存储在磁盘阵列上，实现DVB-VOD和IP-VOD的共享使用。在涉及的各个方面，都做了深入的研究。更多还原

【Abstract】 As the technology and application of DVB and HDTV developing, MPEG2 are used in more and more broad fields. But the lack of programs is still the key difficulty which HDTV and SDTV are facing. And also this affects the application of DVB and VOD system. This thesis intends to solve the problem above. This research accomplished changing the content of DVD into programs accord with MPEG2 TS. For details below:1) Video changed from MPEG2 PS to MPEG2 TS2) Audio of NTSC format that can not be decoded by STB could be changed from Dolby ACS coding standard to MPEG1/2 Layerll standard, and packed into MPEG2 TS format3) Well synchronized with audio and video by a new arithmetic "successive time stamp"This thesis made a introduction of MPEG2 standard in detail;discussed the system timing model;indicated the key during the transforming of video and audio;especially explain how to deal with the PCR. The most important of all, it brought forward a new arithmetic of synchronization of audio and video.This project achieved offering programs for VOD server. It adopted high definition DVD for source; changed video and audio information to MPEGII TS format;storaged information in disk cluster;actualized share used for DVD-VOD and IP-VOD. In every aspects it involved, it reached a high and embedded level.更多还原