[threeseed]

Humans can determine the size of objects because we look for references in the scene and we understand the context.

If a person is standing next to a bush then we roughly know their height since we know the range of sizes that a bush could grow to. Likewise the size of someone like Thanos from Avengers would look odd in a documentary but because its a superhero movie we assume that's normal.

Self driving cars to my knowledge do none of this.