Hand written assembly language functions are the bedrock of any real-world codec implementation. It’s the reason any online video encodes at a reasonable speed or decodes without looking like a stuttery mess. Yet knowledge of writing assembly language functions is slowly disappearing.

This presentation will explain how assembly language functions are important in video codecs and try to teach the audience how to write their first x86 assembly language function. This might sound hard, but high-schoolers have literally written the functions you use every single day. This talk was presented at Demuxed ’23, a conference for video nerds in San Francisco featuring amazing talks like this one.