MPEG4的引入 ■因特网的多媒体应用;多媒体移动通信;多媒体 创作工具;多媒体数据库;交互式视频购物和视 频游戏;以及远程监控和医疗等。 而MPEG-1和MPEG-2采用的基于“帧和基于“块 的压缩算法,不能支持表征图像内容的数据结构。 而这些又正是许多交互式应用所必需的。 当"码率很低时"会产生严重的"方块效应"和"动作 失真",而"低码率"又是多媒体移动通信所必需的 因此,既然预见到了3C融合所出现的需求,就必 须努力克服MPEG-2的不足
◼ 因特网的多媒体应用;多媒体移动通信;多媒体 创作工具;多媒体数据库;交互式视频购物和视 频游戏;以及远程监控和医疗等。 ◼ 而MPEG-1和MPEG-2采用的基于“帧”和基于“块” 的压缩算法,不能支持表征图像内容的数据结构。 而这些又正是许多交互式应用所必需的。 ◼ 当"码率很低时"会产生严重的"方块效应"和"动作 失真",而"低码率"又是多媒体移动通信所必需的。 因此,既然预见到了3C融合所出现的需求,就必 须努力克服MPEG-2的不足。 MPEG4的引入
MPEG4目标 专门用于64kbps以下的甚低速率下的音 视频编码 不仅适应与移动通信和个人通信业务 而且也使用于固定功用通信网和电视电 话 使用于窄带多媒体通信等广泛的应用; 实现基于内容的压缩编码,具有良好的 兼容、伸缩性、可靠性
MPEG4目标 ◼ 专门用于64kbps以下的甚低速率下的音 视频编码; ◼ 不仅适应与移动通信和个人通信业务, 而且也使用于固定功用通信网和电视电 话; ◼ 使用于窄带多媒体通信等广泛的应用; ◼ 实现基于内容的压缩编码,具有良好的 兼容、伸缩性、可靠性
MPEG4 Coding of audio-visual objects, from 1994 ■Part1 Systems Part 10 Advanced Part2Ⅴ isual Video coding ■Part3 audio Part 11 Scene Description Part 4 Conformance testing and Application Engine Part 5 Reference Software Part 12 ISo Base Media a Part 6 Delivery Multimedia File format Integration Framework Part 13 IPMP Extensions Part7 Optimised software for (Intellectual Property MPEG-4 tools Management and Protection Part8 4 on IP framework Part 14 MP4 File format Part 15 AVC File format Part 9 Reference Hardware Description Part 16 Animation Framework eXtension(AFX
MPEG4 Coding of audio-visual objects,from 1994 ◼ Part 1 Systems ◼ Part 2 Visual ◼ Part 3 Audio ◼ Part 4 Conformance testing ◼ Part 5 Reference Software ◼ Part 6 Delivery Multimedia Integration Framework ◼ Part 7 Optimised software for MPEG-4 tools ◼ Part 8 4 on IP framework ◼ Part 9 Reference Hardware Description ◼ Part 10 Advanced Video Coding ◼ Part 11 Scene Description and Application Engine ◼ Part 12 ISO Base Media File Format ◼ Part 13 IPMP Extensions (Intellectual Property Management and Protection ) ◼ Part 14 MP4 File Format ◼ Part 15 AVC File Format ◼ Part 16 Animation Framework eXtension (AFX)
New Project (MPEG a 3DAV: coding of audio and video information from a 3D space 三维空间内音视频信息编码 Scalable video Coding: coding of video with high scalability features and high compression 可伸缩性视频编码
New Project (MPEG) ◼ 3DAV: coding of audio and video information from a 3D space 三维空间内音视频信息编码 ◼ Scalable Video Coding: coding of video with high scalability features and high compression 可伸缩性视频编码
Over view(编码) standardized ways to support ■ Coding(编码) representing units of audio, visual, audiovisual content Composition(合成) I describing how these objects are composed together to produce compound media objects Multiplex(多路复用和合成) a multiplex and synchronize data associated with media objects ■ Interaction(交互性) a interacting with user
OverView(编码) ◼ standardized ways to support: ◼ Coding(编码) ◼ representing units of audio, visual, audiovisual content ◼ Composition(合成) ◼ describing how these objects are composed together to produce compound media objects ◼ Multiplex(多路复用和合成) ◼ multiplex and synchronize data associated with media objects ◼ Interaction(交互性) ◼ interacting with user
System overview(解码) a number of decoders for each type of media(解码) a a composition process which puts the decoded parts together(分量合成) composition ideas are similar to VRML(合成方法) a scene graph of objects composition information is defined in the links hierarchical structure, not necessarily static composition stream has extra information for mp4 a spatial relationships a temporal relationships
System overview(解码) ◼ a number of decoders for each type of media(解码) ◼ a composition process which puts the decoded parts together(分量合成) ◼ composition ideas are similar to VRML(合成方法) ◼ scene graph of objects ◼ composition information is defined in the links ◼ hierarchical structure, not necessarily static ◼ composition stream has extra information for mp4 ◼ spatial relationships ◼ temporal relationships