Video stream is converted to several formats to support the user's device, this conversion process is called video transcoding, which imposes high storage and powerful resources. With emerging of cloud technology, video stream companies adopted to process video on the cloud. Generally, many formats of the same video are made (pre-transcoded) and streamed to the adequate user's device. However, pre-transcoding demands huge storage space and incurs a high-cost to the video stream companies. More importantly, the pre-transcoding of video streams could be hierarchy carried out through different storage types in the cloud. To minimize the storage cost, in this paper, we propose a method to store video streams in the hierarchical storage of the cloud. Particularly, we develop a method to decide which video stream should be pre-transcoded in its suitable cloud storage to minimize the overall cost. Experimental simulation and results show the effectiveness of our approach, specifically, when the percentage of frequently accessed videos is high in repositories, the proposed approach minimizes the overall cost by up to 40 percent.

中文翻译：

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云上按需视频流的经济高效存储

视频流被转换为多种格式以支持用户的设备，这种转换过程称为视频转码，它强加了高存储和强大的资源。随着云技术的兴起，视频流公司纷纷采用云处理视频。通常，制作（预转码）相同视频的多种格式并将其流式传输到合适的用户设备。然而，预转码需要巨大的存储空间，并且给视频流公司带来高成本。更重要的是，视频流的预转码可以通过云中不同的存储类型进行分层。为了最小化存储成本，在本文中，我们提出了一种将视频流存储在云的分层存储中的方法。特别，我们开发了一种方法来决定哪个视频流应该在其合适的云存储中进行预转码，以最大限度地降低整体成本。实验模拟和结果显示了我们方法的有效性，特别是当存储库中经常访问的视频百分比很高时，所提出的方法将总成本最小化了 40%。