muvid.footage.scoring.motionbeat

Motion-to-beat tier: motion_beat_bas + motion_onset_xcorr → song-grid tracks.

Pure given a FramePass (the camera-compensated motion envelope) + the master mixing.audio.BeatGrid (computed ONCE on the clean song). No per-clip beat/onset recomputation — everything maps to song time via the clip’s offset.

• motion_beat_bas — a per-beat Beat Alignment Score (AIST++ [11] idea, localized): each audio beat scores how close its nearest MOTION peak is (exp(−(Δt/σ)²/2)); the score is held over that beat’s interval. NA where the clip has no motion (static / no person) — never 0 (a 0 would penalize valid instrumental footage). Person-present signal.

• motion_onset_xcorr — the clip-level normalized cross-correlation of the motion envelope vs the master onset envelope at the best lag within a bounded A/V-latency window (the lag refines per-clip capture latency). Content-agnostic (covers no-person clips). Held over the clip’s coverage.

Commercial-clean (librosa beats via mixing[beats], numpy motion). See the design §3b.

Functions

motionbeat_tracks(frame_pass, *, clip_id, ...)

The two motion-to-beat tracks for one clip.

muvid.footage.scoring.motionbeat.motionbeat_tracks(frame_pass, *, clip_id, offset_s, beat_times, onset_env, onset_hop_s, t0, hop_s, n)

The two motion-to-beat tracks for one clip.

Return type:

list[ScoreTrack]