https://stackoverflow.com/questions/72486980/combine-lists-in-one-list-in-flutter-dart

stream_processing.dart

import 'dart:typed_data';

void main() async {
  // Generate a stream that emits an [Uint8List] every second containing a single element which is the second index [c]
  final stream = Stream.periodic(Duration(seconds: 1), (c) => Uint8List.fromList([c + 1])).asBroadcastStream();
  
  // Take only 3 seconds
  final rawData = stream.take(3).toList();
  final processedData = stream.take(3).reduce((previous, current) => Uint8List.fromList([...previous, ...current]));

  print(await rawData); // List of Uint8List [[0], [1], [2]]
  print(await processedData); // A single processed Uint8List [0, 1, 2]
}