How papers are selected for Best Paper, Oral, or Highlight presentation at major ML/CV conferences such as CVPR, ICCV, ECCV, NeurIPS, and ICLR? [D]

From what I understand, reviewers usually do not directly vote for these categories or nominate papers themselves. So how does the selection process typically work?

Here are specific questions I wonder

- Who actually selects the candidates: ACs, SACs, program chairs, award committees, or a separate committee?

- Do ACs or committees read the camera-ready version, or is the decision based on the originally submitted/reviewed version?

- Is the selection mostly based on reviewer scores, or do factors like novelty, impact, and discussion among ACs play a bigger role?