Design of a SSIM-optimal 2D post filter with symmetric coefficients for coding artifacts reduction
Kodai Ogawa, Yasuyo Kita, Ichiro Matsuda, Susumu Itoh, Yusuke Kameda · International Workshop on Advanced Imaging Technology (IWAIT) 2022 · 2022
We previously proposed a method of designing a 2D FIR filter that can maximize the well-known objective quality index called SSIM. The designed filter can be used as a post processing tool for lossy image coding methods to reduce coding artifacts. In this scenario, there is a trade-off between the amount of side information on filter coefficients and the obtained gain in image quality. In this paper, effectiveness of the designed filters on the rate-SSIM based coding performance is evaluated under different settings of the size and quantization precision of the filter coefficients. Moreover, we introduce symmetric constraints on the filter coefficients to reduce the side information.