H.264/ AVC和HEVC视频流密码转码的有效性
Effectiveness of Crypto-Transcoding for H.264/AVC and HEVC Video Bit-streams
摘要：
为了避免因需要在代码转换之前解密视频然后在之后重新加密而产生的延迟，本文评估了一种选择性加密（SE）内容保护方案。该方案适用于最近的标准化编解码器，即H. 264/高级视频编码（AVC）和高效视频编码（HEVC）。具体而言，本文概述了一个联合密码转码方案的安全视频码流的transrating。也就是说，它生成新的视频比特率，可能作为HTTP自适应流（HAS）内容分发网络的一部分。该方案将比特率降低到一个或多个较低的期望比特率，而不会在加密/解密过程中消耗时间，这将是使用完全加密时的情况。此外，解密密钥不再需要暴露在中间设备处，包括当在云数据中心中执行速率转换时。该方案的有效性进行了不同的评估：通过检查SE产生的视觉失真;通过计算和比特率开销的程度;以及通过选择加密时的比特流内的选定元素的密码。结果表明，仍然存在：一个内容;量化水平（transrating的加密视频后）;和编解码器类型依赖于任何失真介绍。另一个建议是，高级加密标准（AES）是首选的SE轻量级XOR加密，尽管它在其他地方作为一种实时加密方法。
英文摘要：
To avoid delays arising from a need to decrypt a video prior to transcoding and then re-encrypt it afterwards, this paper assesses a selective encryption (SE) content protection scheme. The scheme is suited to both recent standardized codecs, namely H.264/Advanced Video Coding (AVC) and High Efficiency Video Coding (HEVC). Specifically, the paper outlines a joint crypto-transcoding scheme for secure transrating of a video bitstream. That is to say it generates new video bitrates, possibly as part of an HTTP Adaptive Streaming (HAS) content delivery network. The scheme will reduce the bitrate to one or more lower desired bit-rate without consuming time in the encryption/decryption process, which would be the case when full encryption is used. In addition, the decryption key no longer needs to be exposed at intermediate middleboxes, including when transrating is performed in a cloud datacenter. The effectiveness of the scheme is variously evaluated: by examination of the SE generated visual distortion; by the extent of computational and bitrate overheads; and by choice of cipher when encrypting the selected elements within the bitstream. Results indicate that there remains: a content; quantization level (after transrating of an encrypted video); and codec-type dependency to any distortion introduced. A further recommendation is that the Advanced Encryption Standard (AES) is preferred for SE to lightweight XOR encryption, despite it being taken up elsewhere as a real-time encryption method.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
