sync_logic.py: pure delay_ms computation with the documented sign convention. Caught and fixed a sign error in my own test-fixture ground-truth doc while writing the unit tests: the audio+350ms fixture actually requires delay_ms=-350 (delay video), not +350, since the audio is already the late one. ffmpeg_export.py: ports ffdelay's two-branch command structure (offset video input vs audio input depending on delay_ms sign) plus its documented quirks (leading-zero float formatting, -ss/-t applied to both inputs for clip mode, non-fatal stream-copy warnings surfaced via stderr rather than swallowed). Added an end-to-end integration test (scripts/test_export_roundtrip.py) that independently re-detects event timing in the exported output via ffmpeg scene-change/silence detection (not the same code path used to build the export) and confirms both the positive- and negative-delay branches bring drift down from ~350ms to under 1ms.
651 KiB
651 KiB