Hardware Design for the Separable Symmetric Normalized Wiener Filter of the AV1 Decoder

This paper presents the first dedicated hardware design in the literature for the Separable Symmetric Normalized Wiener Filter (SSNWF) targeting the decoder of the AOM Video 1 (AV1) video format. The SSNWF is one of the last filters into the decoding filtering loop, being part of the Switchable Loop Restoration Filter (SLRF). The SLRF is the main novelty introduced by AV1 in the in-loop filtering process. It is used to attenuate the blurring artifacts, improving the subjective video quality and the coding efficiency. The developed hardware design presented in this paper targets the AV1 decoder and it can process Ultra-High Definition (UHD) videos with 3840x2160 pixels per frame at 60 frames per second (fps) when running at 207.03 MHz. The architecture was synthesized to standard cells using the 40 nm TSMC library, reaching an area of 37.78 Kgates and a power dissipation of 26.36 mW.