End User Video Quality Prediction and Coding Parameters Selection at the Encoder for Robust HEVC Video Transmission

Abstract

Along with the rapid increase in the availability for high quality video formats such as HD (High Definition), UHD (Ultra HD) and HDR (High Dynamic Range), a huge demand for data rates during their transmission has become inevitable. Consequently, the role of video compression techniques has become crucially important in the process of mitigating the data rate requirements. Even though the latest video codec HEVC (High Efficiency Video Coding) has succeeded in significantly reducing the data rate compared to its immediate predecessor H.264/AVC (Advanced Video Coding), the HEVC coded videos in the meantime have become even more vulnerable to network impairments. Therefore, it is equally important to assess the consumers' perceived quality degradation prior to transmitting HEVC coded videos over an error prone network, and to include error resilient features so as to minimize the adverse effects those impairments. To this end, this paper proposes a probabilistic model which accurately predicts the overall distortion of the decoded video at the encoder followed by an accurate QP-λ relationship which can be used in the RDO (Rate Distortion Optimization) process. During the derivation process of the probabilistic model, the impacts from the motion vectors, the pixels in the reference frames and the clipping operations are accounted and consequently the model is capable of minimizing the prediction error as low as 3.11% whereas the state-of-theart methods can't reach below 20.08% under identical conditions. Furthermore, the enhanced RDO process has resulted in 21.41%-43.59% improvement in the BD-rate compared to the state-ofthe-art error resilient algorithms.

Research on Low Frame Rate Video Compression Algorithm in the Context of New Media

“…Recent results, particularly from CVPR's Learning Image Compression Challenges (CLIC), suggest that this novel approach, which typically trains end-to-end, may have good potential to further improve compression efficiency [6]. Kulupana et al [7] propose a probabilistic model that accurately predicts the overall distortion of the decoded video at the encoder followed by an accurate QP-λ relationship, which can be used in the rate-distortion optimization (RDO) process. Kulupana et al [7] propose a novel RC method which considers distortion characteristics for model parameters updating for quality enhancement, including a low-complexity-based I-frame QP decision strategy of low-delay applications.…”

Measuring, Modeling and Integrating Time-Varying Video Quality in End-to-End Multimedia Service Delivery: A Review and Open Challenges

“…For instance, probabilistic models that predict the overall distortion at the decoder based on the impact on motion vectors, the pixels in the reference frames, and the clipping operations. The predicted error is used in the encoders to select the optimum coding parameters to facilitate robust video transmission in lossy channels [203]. A similar approach is undertaken in [204] where the optimal error concealment strategies at the decoder are identified in the encoder by simulating the transmission errors.…”