Beat-synced short-form edits for a music release

A demo built for a specific brief. Not client work: the material shown is sample data, so what is on display is the mechanism.

I built a beat-synced cut-list demo for a placeholder single. A tempo map (bar 1 at 92 BPM, bar 5 at 124 BPM, 4/4), a section map of 6 sections over 60 bars and 8 lyric lines go in. Four edits come out, each tied to a post day around release: a hook-first teaser (15.48 s, 22 cuts, with a two-bar title hold), an intro edit across the tempo change, a lyric card where every lyric line starts on a cut, and a transition edit with eight half-beat flash cuts into the hook downbeat. The build integrates the tempo map to song time and converts 84 cuts to frames at 30 fps; the worst error is 0.484 frames. A fixed-frame rhythm at the opening tempo would drift up to 122 frames. Each edit is rendered as a 540×960 preview with FFmpeg and read back with scene detection: 84 of 84 cuts found at the planned frame. Cut lists ship as CSV and CMX 3600 EDL, with a 240-beat grid. Any failed check exits non-zero and writes nothing.