Video editing needs separate source and output timelines, tutorial argues

A tutorial explains that edited video notes can point to the wrong moment when timestamps from the original recording are used on the edited output. It describes a small local JavaScript mapper that converts between source and output times for hard cuts, reordered spans, repeated ranges and constant playback speeds. The example shows one source timestamp appearing twice in the output and another not appearing at all, so lookups must return lists rather than single answers. The author notes the code is educational rather than a production schema, and discloses that it was published by a commercial AI video editor and written with an AI agent.