tubakhxn/pedestrian-vehicle-safety-cv — reverse-engineered prompt

Build me a simple Python app for crosswalk safety monitoring from traffic video. I want to run one file, give it a path to a video, or just press Enter to use a demo clip, and then watch it analyze the scene in real time.

It should detect pedestrians and vehicles, keep tracking the same ones across frames, draw the crosswalk related zones on screen, and figure out who is waiting, who is actively crossing, and whether nearby vehicles are stopped or still moving. If a person is crossing and a vehicle is not yielding, show a clear warning on the video so the unsafe situation is obvious.

Please include the basic on screen HUD, automatic download of the model and demo video on first run, and support for ordinary video files instead of needing a webcam. A fixed default zone layout is fine for now. Keep it easy to run and reasonably clean to read. If anything is unclear, look up current docs online and make sensible choices.