Video transcoding is the process of converting a video to the format supported by the viewer's device. Video transcoding requires huge storage and computational resources, thus, many video stream providers choose to carry it out on the cloud. Video streaming providers generally need to prepare several formats of the same video (termed pre-transcoding) and stream the appropriate format to the viewer. However, pre-transcoding requires enormous storage space and imposes a significant cost to the stream provider. More importantly, pre-transcoding proven to be inefficient due to the long-tail access pattern to video streams in a repository. To reduce the incurred cost, in this research, we propose a method to partially pre-transcode video streams and re-transcode the rest of it in an on-demand manner. We will develop a method to strike a trade-off between pre-transcoding and on-demand transcoding of video streams to reduce the overall cost. Experimental results show the efficiency of our approach, particularly, when a high percentage of videos are accessed frequently. In such repositories, the proposed approach reduces the incurred cost by up to 70\%.
翻译:视频转换是将视频转换成由查看器设备支持的格式的过程。视频转换需要大量的存储和计算资源,因此,许多视频流提供商选择在云层上进行。视频流提供商通常需要准备同一视频的几种格式(传输前的间隔),并将适当的格式传送给查看者。然而,传输前需要巨大的存储空间,给数据流提供商带来巨大的成本。更重要的是,由于对存储器视频流的长尾访问模式,预先传输编码证明效率低下。为了降低所发生的费用,我们在这一研究中建议了一种方法,即部分对视频流进行传输前的编码,并根据需求对其余部分进行重新编码。我们将开发一种方法,在视频流的传输前和按需转换之间实现交易,以降低总体成本。实验结果表明我们的方法的效率,特别是当经常访问高比例的视频时。在这类存储库中,拟议的方法将成本降低到70 。