arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2311.08074cs.MM
收藏

面向绿色直播的内容自适应可变帧率编码方案

Content-Adaptive Variable Framerate Encoding Scheme for Green Live Streaming

Vignesh V Menon, Samira Afzal, Prajit T Rajendran, Klaus Schoeffmann, Radu Prodan, Christian Timmerer

AI总结:

本文提出内容自适应可变帧率(CVFR)编码方案,通过预测优化帧率和预设,在相同码率下提升PSNR和VMAF,并显著降低编码与存储能耗,适用于绿色直播流媒体。

摘要:

自适应实时视频流应用在会话中使用固定的预定义配置,包括恒定帧率和编码预设。然而,为码率阶梯中的每个表示选择优化的帧率和预设,可以提升感知质量,改善计算资源分配,从而提高流媒体能效。特别是,低码率表示采用低帧率可减少压缩伪影并降低编码能耗。此外,优化的预设可能带来更好的压缩效率。为此,本文提出一种内容自适应可变帧率(CVFR)编码方案,提供两种运行模式:生态(ECO)模式和高品质(HQ)模式。CVFR-ECO通过预测码率阶梯中每个表示的优化帧率,以实现最高的编码能耗节省。CVFR-HQ则进一步利用基于低复杂度离散余弦变换能量的空间和时间特征,预测每个表示的优化帧率-编码预设对,以提升压缩效率和可持续存储。我们使用x264开源视频编码器展示了CVFR的优势。结果表明,与最快预设最高帧率编码相比,在相同码率下,CVFR-ECO平均PSNR和VMAF分别提高0.02 dB和2.50点。考虑六个VMAF点的恰可察觉差异(JND),CVFR-ECO平均编码和存储能耗分别降低34.54%和76.24%。相比之下,CVFR-HQ在相同码率下平均PSNR和VMAF分别提高2.43 dB和10.14点。最后,考虑六个VMAF点的JND,CVFR-HQ平均存储能耗降低83.18%。

英文摘要:

Adaptive live video streaming applications use a fixed predefined configuration for the bitrate ladder with constant framerate and encoding presets in a session. However, selecting optimized framerates and presets for every bitrate ladder representation can enhance perceptual quality, improve computational resource allocation, and thus, the streaming energy efficiency. In particular, low framerates for low-bitrate representations reduce compression artifacts and decrease encoding energy consumption. In addition, an optimized preset may lead to improved compression efficiency. To this light, this paper proposes a Content-adaptive Variable Framerate (CVFR) encoding scheme, which offers two modes of operation: ecological (ECO) and high-quality (HQ). CVFR-ECO optimizes for the highest encoding energy savings by predicting the optimized framerate for each representation in the bitrate ladder. CVFR-HQ takes it further by predicting each representation's optimized framerate-encoding preset pair using low-complexity discrete cosine transform energy-based spatial and temporal features for compression efficiency and sustainable storage. We demonstrate the advantage of CVFR using the x264 open-source video encoder. The results show that CVFR-ECO yields an average PSNR and VMAF increase of 0.02 dB and 2.50 points, respectively, for the same bitrate, compared to the fastest preset highest framerate encoding. CVFR-ECO also yields an average encoding and storage energy consumption reduction of 34.54% and 76.24%, considering a just noticeable difference (JND) of six VMAF points. In comparison, CVFR-HQ yields an average increase in PSNR and VMAF of 2.43 dB and 10.14 points, respectively, for the same bitrate. Finally, CVFR-HQ resulted in an average reduction in storage energy consumption of 83.18%, considering a JND of six VMAF points.

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。

↑