Video streaming, in various forms of video on demand (VOD), live, and 360 degree streaming, has grown dramatically during the past few years. In comparison to traditional cable broadcasters whose contents can only be watched on TVs, video streaming is ubiquitous and viewers can flexibly watch the video contents on various devices, ranging from smart-phones to laptops and large TV screens. Such ubiquity and flexibility are enabled by interweaving multiple technologies, such as video compression, cloud computing, content delivery networks, and several other technologies. As video streaming gains more popularity and dominates the Internet traffic, it is essential to understand the way it operates and the interplay of different technologies involved in it. Accordingly, the first goal of this paper is to unveil sophisticated processes to deliver a raw captured video to viewers' devices. In particular, we elaborate on the video encoding, transcoding, packaging, encryption, and delivery processes. We survey recent efforts in academia and industry to enhance these processes. As video streaming industry is increasingly becoming reliant on cloud computing, the second goal of this survey is to explore and survey the ways cloud services are utilized to enable video streaming services. The third goal of the study is to position the undertaken research works in cloud-based video streaming and identify challenges that need to be obviated in future to advance cloud-based video streaming industry to a more flexible and user-centric service.
翻译:在过去几年里,通过各种需求视频(VOD)、现场视频和360度视频(VOD)、现场视频流和360度视频流,视频流在过去几年中急剧增长。与传统有线广播公司相比,其内容只能在电视上观看,视频流无处不在,观众可以灵活地观看各种设备(从智能手机到笔记本电脑和大型电视屏幕)的视频内容。这种无处不在和灵活性是通过视频压缩、云计算、内容传输网络和其他若干技术等多种互交技术实现的。随着视频流越来越受欢迎并主导互联网的流通,因此,了解视频流的运作方式以及其中涉及的不同技术的相互作用至关重要。因此,本文的第一个目标是公布各种设备,从智能手机到笔记笔记笔记电脑和大型电视屏幕屏幕屏幕的复杂过程。我们调查学术界和工业界最近为加强这些过程所作的努力。随着视频流产业越来越依赖云计算,本次调查的第三个目标是探索和调查云流服务如何利用云流用户服务来推进视频流研究。