This paper examines dependencies of voice and video contents on human perception of group (or inter-destination) synchronization error in remote learning by Quality of Experience (QoE) assessment. In our assessment, w...This paper examines dependencies of voice and video contents on human perception of group (or inter-destination) synchronization error in remote learning by Quality of Experience (QoE) assessment. In our assessment, we use two videos and three voices (two voices for one video and one voice for the other video). We also investigate influences of silence periods in the voices and temporal relations between the voices and videos (called the tightly-coupled and loosely-coupled contents here). The voices are spoken by a teacher according to the videos. Each subject as a student assesses the group synchronization quality by watching each lecture video and the corresponding explanation voice, and then the subject answers whether he/she perceives the group synchronization error or not. As a result, assessment results illustrate that silence periods mitigate the perception rate of the error, and we can also find that we can more easily perceive the error for tightly-coupled contents than loosely-coupled ones.展开更多
随着高清电视和网络媒体的快速发展,音视频同步技术在广播电视节目制作中的重要性日益突出。通过对当前音视频同步系统的分析,深入研究节目时钟参考(Program Clock Reference,PCR)、显示时间戳(Presentation Time Stamp,PTS)/解码时间戳...随着高清电视和网络媒体的快速发展,音视频同步技术在广播电视节目制作中的重要性日益突出。通过对当前音视频同步系统的分析,深入研究节目时钟参考(Program Clock Reference,PCR)、显示时间戳(Presentation Time Stamp,PTS)/解码时间戳(Decoding Time Stamp,DTS)、音视频缓冲区控制等关键技术在实际制作环境中的应用。基于自适应缓冲区控制的音视频同步方案能将音视频延迟控制在±15 ms以内,满足广播级节目制作要求。展开更多
随着电视新闻节目制作技术的发展,多机位编辑日益成为提升节目品质和效率的关键手段。精确时间协议(Precision Time Protocol,PTP)有助于实现电视新闻多机位编辑的音视频同步。介绍PTP的基本原理和优势,分析电视新闻多机位编辑对于音视...随着电视新闻节目制作技术的发展,多机位编辑日益成为提升节目品质和效率的关键手段。精确时间协议(Precision Time Protocol,PTP)有助于实现电视新闻多机位编辑的音视频同步。介绍PTP的基本原理和优势,分析电视新闻多机位编辑对于音视频同步的特殊要求以及传统同步技术的局限性。在此基础上,从系统架构设计、主时钟选择与同步、延迟测量与补偿等方面详细阐述基于PTP的音视频同步技术在多机位编辑中的应用。展开更多
文摘This paper examines dependencies of voice and video contents on human perception of group (or inter-destination) synchronization error in remote learning by Quality of Experience (QoE) assessment. In our assessment, we use two videos and three voices (two voices for one video and one voice for the other video). We also investigate influences of silence periods in the voices and temporal relations between the voices and videos (called the tightly-coupled and loosely-coupled contents here). The voices are spoken by a teacher according to the videos. Each subject as a student assesses the group synchronization quality by watching each lecture video and the corresponding explanation voice, and then the subject answers whether he/she perceives the group synchronization error or not. As a result, assessment results illustrate that silence periods mitigate the perception rate of the error, and we can also find that we can more easily perceive the error for tightly-coupled contents than loosely-coupled ones.
文摘随着高清电视和网络媒体的快速发展,音视频同步技术在广播电视节目制作中的重要性日益突出。通过对当前音视频同步系统的分析,深入研究节目时钟参考(Program Clock Reference,PCR)、显示时间戳(Presentation Time Stamp,PTS)/解码时间戳(Decoding Time Stamp,DTS)、音视频缓冲区控制等关键技术在实际制作环境中的应用。基于自适应缓冲区控制的音视频同步方案能将音视频延迟控制在±15 ms以内,满足广播级节目制作要求。
文摘随着电视新闻节目制作技术的发展,多机位编辑日益成为提升节目品质和效率的关键手段。精确时间协议(Precision Time Protocol,PTP)有助于实现电视新闻多机位编辑的音视频同步。介绍PTP的基本原理和优势,分析电视新闻多机位编辑对于音视频同步的特殊要求以及传统同步技术的局限性。在此基础上,从系统架构设计、主时钟选择与同步、延迟测量与补偿等方面详细阐述基于PTP的音视频同步技术在多机位编辑中的应用。
