An Energy-Aware Caching Algorithm for VVC Video Streaming in Content Delivery Networks

This study introduces a video caching algorithm that consolidates the processing workflows of multi-layer VVC sources and diverse target codecs (e.g., VVC, HEVC, H.264) into a single formalized structure. To tackle the challenges associated with transcoding costs and selecting optimal transcoding paths across codecs, the Energy-Aware Video Extracting and Transcoding Graph (EWVETG) is introduced. The EWVETG considers both encoder and decoder energy usage, in addition to processing latency, and integrates Peak Signal-to-Noise Ratio (PSNR) as a Quality of Experience (QoE) metric in its decision making process. Building upon the EWVETG, an energy-aware caching algorithm is further developed, which operates at the level of video segments and adaptive layers. The algorithm uses a multi-factor density scoring system to guide decisions on content inclusion and eviction. Simulation results indicate that the proposed method can reduce end-to-end energy consumption and transcoding overhead on edge servers, while maintaining satisfactory video quality.