Precise Encoding Complexity Control for Versatile Video Coding

作     者：Huang, Yan Xu, Jun Zhu, Chen Song, Li Zhang, Wenjun 

作者机构：Shanghai Jiao Tong Univ Inst Image Commun & Network Engn Shanghai 200240 Peoples R China Shanghai Jiao Tong Univ Inst Image Commun & Network Engn MoE Key Lab Artificial Intelligence AI Inst Shanghai 200240 Peoples R China 

出 版 物：《IEEE TRANSACTIONS ON BROADCASTING》 (IEEE Trans Broadcast)

年 卷 期：2023年第69卷第1期

页      面：33-48页

核心收录：

学科分类：0810[工学-信息与通信工程] 0808[工学-电气工程] 08[工学] 

基　　金：National Key Research and Development Project of China [2019YFB1802701] MoE-China Mobile Research Fund Project [MCM20180702] Chinese National Science Funding 111 Project [B07022] Shanghai Key Laboratory of Digital Media Processing and Transmissions Sheitc 

主　　题：Encoding Complexity theory Resource management Partitioning algorithms Switches Transforms Prediction algorithms Versatile video coding (VVC) complexity control fast partition precise 

摘      要：Complexity reduction is a commonly used method to deal with complicated video coding standards, such as High Efficiency Video Coding (HEVC) and Versatile Video Coding (VVC). But the unstable performance under different video contents and Quantization Parameters (QPs) makes it difficult to precisely specify the target encoding time of every single sequence, which limits the practical use of the encoder. Inspired by rate control, in this paper, encoding time budget is regarded as a resource. We incorporate the hierarchical Group of Picture (GOP) encoding structure, the non-accelerated proportion, and block content variation within the frame, and design a top-down allocation and bottom-up feedback scheme, to achieve precise control of encoding complexity by controlling the maximum depth of QuadTree with nested Multi-type Tree (QTMT). In the scheme, Temporal ID (Tid)-based, Sum of Absolute Transformed Difference (SATD)-based methods and Linear (L) Model are designed to facilitate weighted allocation and feedback. The relationship between Planar Cost and encoding time is exploited as a Time-Cost (T-C) model, which guides the selection of Largest Coding Unit (LCU) encoding strategies in I-frames. For B-frames, we investigate a switching suppression assisted status-based method, to efficiently decide the encoding strategy of each LCU. Through the collaboration of the proposed technologies in the scheme, given any encoding time target achievable, encoding strategies will be automatically switched to help the actual encoding time gradually approach the target. To the best of our knowledge, this work is the first work on VVC-based encoding complexity control. The proposed scheme supports directly specifying the target encoding time or target Frame Per Second (FPS), and accurately realizing it within one pass. According to experimental results, under the target encoding time ratio of 80%, 60% and 40%, the average encoding time error is kept under 0.24%, 0.03% and 0.02% by our