keepRanges static method

List<TimeRange> keepRanges(List<TimeRange> silences, Duration total, { Duration padding = const Duration(milliseconds: 120), Duration minKeep = const Duration(milliseconds: 300), })

The complement of silences within total, widened by padding and without ranges shorter than minKeep.

Implementation

static List<TimeRange> keepRanges(
  List<TimeRange> silences,
  Duration total, {
  Duration padding = const Duration(milliseconds: 120),
  Duration minKeep = const Duration(milliseconds: 300),
}) {
  final sorted = [...silences]..sort((a, b) => a.start.compareTo(b.start));
  final keep = <TimeRange>[];
  var cursor = Duration.zero;
  void add(Duration from, Duration to) {
    final s = from < Duration.zero ? Duration.zero : from;
    final e = to > total ? total : to;
    if (e - s < minKeep) return;
    // Padding can make neighbours overlap; merge them.
    if (keep.isNotEmpty && s <= keep.last.end) {
      keep[keep.length - 1] = TimeRange(keep.last.start, e);
    } else {
      keep.add(TimeRange(s, e));
    }
  }

  for (final silence in sorted) {
    if (silence.start > cursor) add(cursor - padding, silence.start + padding);
    if (silence.end > cursor) cursor = silence.end;
  }
  if (cursor < total) add(cursor - padding, total);
  return keep;
}