I think they mean that video decoders and encoders tend to have custom assembly code for speedup.
And? It's common knowledge that the "reference" or "research" version of any codec is always quite high level to get development going and actually produce a working bitstream
alt Hacker News
And? It's common knowledge that the "reference" or "research" version of any codec is always quite high level to get development going and actually produce a working bitstream