I think the article could have used a little more on chroma subsampling ("downsampling," per the article). A couple examples: It is basically an optional step (

I think the article could have used a little more on chroma subsampling ("downsampling," per the article). A couple examples: It is basically an optional step (in the case of 4:4:4). And the visual impact on heavily saturated colors (looking at you, bright red).