Synthetic lavfi sources — nothing is uploaded, everything renders locally.

Pattern

SMPTE RP 219 HD color bars

Format

Duration (seconds)

Burn-inRunning timecode (drop-frame, from 00:00:00;00)Safe-area markers (93% action / 90% title + center cross)

Audio (1 kHz)

Container

HD SMPTE bars · 1080p59.94 · 30s · 1 kHz −20 dBFS · timecode

Generated file loops here

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