This project took place over Summer 2023 as part of the Google Summer of Code (GSoC). This project's objective was to implement the in-loop filter portion of the new Versatile Video Codec (VVC, H.266) decoder currently under development in FFmpeg. The In-Loop filters that I chose to implement are the Sample Adaptive Offset (SAO) and Deblocking filters. These filters are already implemented in C, and my objective was to implement x86_64 assembly versions that were more performant than the C "template" version.