← all videos

A person speaks normally in a quiet indoor room while facing the camera, then raises both hands and fully covers their mouth, clearly blocking the direct path of sound; instead of becoming muffled, the voice becomes louder, clearer, and brighter once the mouth is covered.

C3-4-06 Environment Transition · env_transition_anti_physics anti-physics principle: Anti-Physics (Anti)
Seedance 2.0ByteDance · proprietary
Kling 3.0 OmniKuaishou · proprietary
Veo 3.1Google · proprietary
LTX-2.3Lightricks · open
Ovi 1.1character.ai · open
JavisDiT++JavisDiT · open
MagiHumanGAIR-NLP · open
Per-prompt rubric

Basic standards

Visual presence

  • a person

Event: a person speaks then covers their mouth with both hands

Audio presence

  • a person

Sound: a person speaking

Key standards

Visual physical commonsense (V-PC)

  • A person speaks at the start of the clip facing the camera with hands away from the face and mouth fully visible.
  • The person then raises both hands and fully covers the mouth, clearly blocking the direct path of sound for the rest of the clip.

Audio physical commonsense (A-PC)

  • The voice in the open-mouth phase has the natural articulation and brightness of normal indoor speech.
  • The voice in the hands-covered phase becomes louder, clearer, and brighter than the open-mouth phase, with increased high-frequency content.

Cross-modal physical commonsense (AV-PC)

  • The shift to louder clearer brighter voice aligns in time with the moment both hands visibly cover the mouth.