A combined SAO and de-blocking filter architecture for HEVC video decoder

The up-coming video compression standard, high efficiency video coding (HEVC), reduces 50% bit rates in encoding video sequences with same picture quality compared to H.264/AVC. In the in-loop filter (LF) part of HEVC, sample adaptive offset (SAO) is newly added and de-blocking filter (DBF) has been changed a lot. Thus how to construct a high speed and low cost VLSI architecture for HEVC SAO and de-blocking filter is a challenge. In this article, we propose a HEVC LF architecture composed of fully utilized de-blocking filter and SAO. Block based SAO and DBF are employed in this architecture to achieve seamless pipeline between them. The implementation results show that it can be synthesized to 240MHz with 65nm technology. Thus this solution can process 3.84G pixels/s and support 4320p(7680×4320)@120fps decoding.