Download a sub stream with youtube_explode_dart - flutter

Question

I'm developing a Flutter app, using the package youtube_explode_dart.
Currently I download all the audio stream, then crop it using ffmpeg. Quickly this looks like :
var id = "aboZctrHfK8";
var file = File("mySong.mp4");
var start = "2000ms";
var end = "5000ms";
// Downloading audio only
var manifest = await yt.videos.streamsClient.getManifest(id);
var audio = manifest.audioOnly.first;
var audioStream = yt.videos.streamsClient.get(audio);
var output = file.openWrite(mode: FileMode.writeOnlyAppend);
for (final data in audioStream) {
output.add(data);
}
// Croping audio
FlutterFFmpeg _flutterFFmpeg = new FlutterFFmpeg();
await _flutterFFmpeg.executeWithArguments([
"-v", "error",
"-ss", start,
"-to", end,
"-i", file.path,
"-acodec", "copy", "myCroppedSong.mp4"]);
Now I'm facing another issue: Some videos are really heavy and take a while to download. This is not acceptable for my end users, especially since I only want part of the original audio.
Is there a way to download only a subset of the audio stream?
Something like:
for (final data in audioStream.subset(start, end)) {
output.add(data);
}
It would be anwsome!

Answer 1

import 'package:youtube_explode_dart/youtube_explode_dart.dart';
// Initialize the YoutubeExplode instance.
final yt = YoutubeExplode();
Future<void> ExplodeDown() async {
stdout.writeln('Type the video id or url: ');
var url = stdin.readLineSync()!.trim();
// Save the video to the download directory.
Directory('downloads').createSync();
// Download the video.
await download(url);
yt.close();
exit(0);
}
Future<void> download(String id) async {
// Get video metadata.
var video = await yt.videos.get(id);
// Get the video manifest.
var manifest = await yt.videos.streamsClient.getManifest(id);
var streams = manifest.videoOnly;
// Get the audio track with the highest bitrate.
var audio = streams.first;
var audioStream = yt.videos.streamsClient.get(audio);
// Compose the file name removing the unallowed characters in windows.
var fileName = '${video.title}.${audio.container.name}'
.replaceAll(r'\', '')
.replaceAll('/', '')
.replaceAll('*', '')
.replaceAll('?', '')
.replaceAll('"', '')
.replaceAll('<', '')
.replaceAll('>', '')
.replaceAll('|', '');
var file = File('downloads/$fileName');
// Delete the file if exists.
if (file.existsSync()) {
file.deleteSync();
}
// Open the file in writeAppend.
var output = file.openWrite(mode: FileMode.writeOnlyAppend);
// Track the file download status.
var len = audio.size.totalBytes;
var count = 0;
// Create the message and set the cursor position.
var msg = 'Downloading ${video.title}.${audio.container.name}';
stdout.writeln(msg);
// Listen for data received.
// var progressBar = ProgressBar();
await for (final data in audioStream) {
// Keep track of the current downloaded data.
count += data.length;
// Calculate the current progress.
var progress = ((count / len) * 100).ceil();
print (progress);
// Update the progressbar.
// progressBar.update(progress);
// Write to file.
output.add(data);
}
await output.close();
}
**How to download load youtube video & audio & play stream audio **

Answer 2

String youTubeLink = "https://www.youtube.com/watch?v=Ja-85lFDSEM";
Future<void> _downloadVideo(youTubeLink) async{
final yt = YoutubeExplode();
final video = await yt.videos.get(youTubeLink);
// Get the video manifest.
final manifest = await yt.videos.streamsClient.getManifest(youTubeLink);
final streams = manifest.muxed;
final audio = streams.first;
final audioStream = yt.videos.streamsClient.get(audio);
final fileName = '${video.title}.${audio.container.name.toString()}'
.replaceAll(r'\', '')
.replaceAll('/', '')
.replaceAll('*', '')
.replaceAll('?', '')
.replaceAll('"', '')
.replaceAll('<', '')
.replaceAll('>', '')
.replaceAll('|', '');
final dir = await getApplicationDocumentsDirectory();
final path = dir.path;
final directory = Directory('$path/video/');
await directory.create(recursive: true);
final file = File('$path/video/$fileName');
final output = file.openWrite(mode: FileMode.writeOnlyAppend);
var len = audio.size.totalBytes;
var count = 0;
var msg = 'Downloading ${video.title}.${audio.container.name}';
stdout.writeln(msg);
await for (final data in audioStream){
count += data.length;
var progress = ((count / len) * 100).ceil();
print(progress);
output.add(data);
}
await output.flush();
await output.close();
}