v10/packages/utils/src/dom/time-ranges.ts

/** Converts a TimeRanges object to an array of [start, end] tuples. */
export function serializeTimeRanges(ranges: TimeRanges): Array<[number, number]> {
  const result: Array<[number, number]> = [];

  for (let i = 0; i < ranges.length; i++) {
    result.push([ranges.start(i), ranges.end(i)]);
  }

  return result;
}