Performance Comparison of Weak Filtering in HEVC and VVC

Junghyun Lee,Jechang Jeong

doi:10.3390/electronics9060960

Abstract

This study describes the need to improve the weak filtering method for the in-loop filter process used identically in versatile video coding (VVC) and high efficiency video coding (HEVC). The weak filtering process used by VVC has been adopted and maintained since Draft Four during H.265/advanced video coding (AVC) standardization. Because the encoding process in the video codec utilizes block structural units, deblocking filters are essential. However, as many of the deblocking filters require a complex calculation process, it is necessary to ensure that they have a reasonable effect. This study evaluated the performance of the weak filtering portion of the VVC and confirmed that it is not functioning effectively, unlike its performance in the HEVC. The method of excluding the whole of weak filtering from VVC, which is a non-weak filtering method, should be considered in VVC standardization. In experimental result in this study, the non-weak filtering method brings 0.40 Y-Bjontegaard-Delta Bit-Rate (BDBR) gain over VVC Test Model (VTM) 6.0.

Highlights

The video compression standard in which block unit encoding takes place requires a deblocking filter to reduce blocking artifacts
The degree of blocking artifacts is determined according to the conditions of the reconstructed pixels at the block boundary and the quantization parameter (QP) value used for encoding
The Algorithm 1 (b) part includes the calculation of delta values for the block boundary and the calculation of weak filtering for the two pixels p0 and q0 nearest the boundary

Summary

Introduction

The video compression standard in which block unit encoding takes place requires a deblocking filter to reduce blocking artifacts. In the high efficiency video coding (HEVC) standard, vertical edges are treated in picture units, followed by horizontal edges in picture units Through this method, parallel processing is possible, which is beneficial in terms of complexity [2,3,4]. For blocks with weak filtering selected as the deblocking filter, the additional process of evaluating the situation of the pixels on the boundary determines whether the two or four pixels closest to the boundary are filtered. These current weak filtering methods have been adopted in H.265/AVC Draft Four and have remained the same to date [5,6]

Methods

Results

Conclusion