Download all supported audio languages

Readme.md

@@ -56,6 +56,7 @@ To learn more about the war and how you can help, [click here](https://tyrrrz.me
 - Download videos from playlists or channels
 - Download videos by search query
 - Selectable video quality and format
+- Automatically embed audio tracks in alternative languages
 - Automatically embed subtitles
 - Automatically inject media tags
 - Log in with a YouTube account to access private content

YoutubeDownloader.Core/Downloading/VideoDownloadOption.cs

@@ -18,7 +18,10 @@ IReadOnlyList<IStreamInfo> StreamInfos
 
 public partial record VideoDownloadOption
 {
-    internal static IReadOnlyList<VideoDownloadOption> ResolveAll(StreamManifest manifest)
+    internal static IReadOnlyList<VideoDownloadOption> ResolveAll(
+        StreamManifest manifest,
+        bool includeLanguageSpecificAudioStreams = true
+    )
     {
         IEnumerable<VideoDownloadOption> GetVideoAndAudioOptions()
         {
@@ -40,22 +43,50 @@ IEnumerable<VideoDownloadOption> GetVideoAndAudioOptions()
                 // Separate audio + video stream
                 else
                 {
-                    // Prefer audio stream with the same container
-                    var audioStreamInfo = manifest
+                    var audioStreamInfos = manifest
                         .GetAudioStreams()
+                        // Prefer audio streams with the same container
                         .OrderByDescending(s => s.Container == videoStreamInfo.Container)
                         .ThenByDescending(s => s is AudioOnlyStreamInfo)
                         .ThenByDescending(s => s.Bitrate)
-                        .FirstOrDefault();
+                        .ToArray();
 
-                    if (audioStreamInfo is not null)
+                    // Prefer language-specific audio streams, if available and if allowed
+                    var languageSpecificAudioStreamInfos = includeLanguageSpecificAudioStreams
+                        ? audioStreamInfos
+                            .Where(s => s.AudioLanguage is not null)
+                            .DistinctBy(s => s.AudioLanguage)
+                            // Default language first so it's encoded as the first audio track in the output file
+                            .OrderByDescending(s => s.IsAudioLanguageDefault)
+                            .ToArray()
+                        : [];
+
+                    // If there are language-specific streams, include them all
+                    if (languageSpecificAudioStreamInfos.Any())
                     {
                         yield return new VideoDownloadOption(
                             videoStreamInfo.Container,
                             false,
-                            new IStreamInfo[] { videoStreamInfo, audioStreamInfo }
+                            [videoStreamInfo, .. languageSpecificAudioStreamInfos]
                         );
                     }
+                    // If there are no language-specific streams, download the single best quality audio stream
+                    else
+                    {
+                        var audioStreamInfo = audioStreamInfos
+                            // Prefer audio streams in the default language (or non-language-specific streams)
+                            .OrderByDescending(s => s.IsAudioLanguageDefault ?? true)
+                            .FirstOrDefault();
+
+                        if (audioStreamInfo is not null)
+                        {
+                            yield return new VideoDownloadOption(
+                                videoStreamInfo.Container,
+                                false,
+                                [videoStreamInfo, audioStreamInfo]
+                            );
+                        }
+                    }
                 }
             }
         }
@@ -66,7 +97,10 @@ IEnumerable<VideoDownloadOption> GetAudioOnlyOptions()
             {
                 var audioStreamInfo = manifest
                     .GetAudioStreams()
-                    .OrderByDescending(s => s.Container == Container.WebM)
+                    // Prefer audio streams in the default language (or non-language-specific streams)
+                    .OrderByDescending(s => s.IsAudioLanguageDefault ?? true)
+                    // Prefer audio streams with the same container
+                    .ThenByDescending(s => s.Container == Container.WebM)
                     .ThenByDescending(s => s is AudioOnlyStreamInfo)
                     .ThenByDescending(s => s.Bitrate)
                     .FirstOrDefault();
@@ -89,7 +123,10 @@ IEnumerable<VideoDownloadOption> GetAudioOnlyOptions()
             {
                 var audioStreamInfo = manifest
                     .GetAudioStreams()
-                    .OrderByDescending(s => s.Container == Container.Mp4)
+                    // Prefer audio streams in the default language (or non-language-specific streams)
+                    .OrderByDescending(s => s.IsAudioLanguageDefault ?? true)
+                    // Prefer audio streams with the same container
+                    .ThenByDescending(s => s.Container == Container.Mp4)
                     .ThenByDescending(s => s is AudioOnlyStreamInfo)
                     .ThenByDescending(s => s.Bitrate)
                     .FirstOrDefault();

YoutubeDownloader.Core/Downloading/VideoDownloader.cs

@@ -19,20 +19,26 @@ public class VideoDownloader(IReadOnlyList<Cookie>? initialCookies = null)
 
     public async Task<IReadOnlyList<VideoDownloadOption>> GetDownloadOptionsAsync(
         VideoId videoId,
+        bool includeLanguageSpecificAudioStreams = true,
         CancellationToken cancellationToken = default
     )
     {
         var manifest = await _youtube.Videos.Streams.GetManifestAsync(videoId, cancellationToken);
-        return VideoDownloadOption.ResolveAll(manifest);
+        return VideoDownloadOption.ResolveAll(manifest, includeLanguageSpecificAudioStreams);
     }
 
     public async Task<VideoDownloadOption> GetBestDownloadOptionAsync(
         VideoId videoId,
         VideoDownloadPreference preference,
+        bool includeLanguageSpecificAudioStreams = true,
         CancellationToken cancellationToken = default
     )
     {
-        var options = await GetDownloadOptionsAsync(videoId, cancellationToken);
+        var options = await GetDownloadOptionsAsync(
+            videoId,
+            includeLanguageSpecificAudioStreams,
+            cancellationToken
+        );
 
         return preference.TryGetBestOption(options)
             ?? throw new InvalidOperationException("No suitable download option found.");

YoutubeDownloader.Core/YoutubeDownloader.Core.csproj

@@ -5,8 +5,8 @@
     <PackageReference Include="Gress" Version="2.1.1" />
     <PackageReference Include="JsonExtensions" Version="1.2.0" />
     <PackageReference Include="TagLibSharp" Version="2.3.0" />
-    <PackageReference Include="YoutubeExplode" Version="6.4.4" />
-    <PackageReference Include="YoutubeExplode.Converter" Version="6.4.4" />
+    <PackageReference Include="YoutubeExplode" Version="6.5.0" />
+    <PackageReference Include="YoutubeExplode.Converter" Version="6.5.0" />
   </ItemGroup>
 
 </Project>

YoutubeDownloader/Services/SettingsService.cs

@@ -49,6 +49,13 @@ public bool IsAuthPersisted
         set => SetProperty(ref _isAuthPersisted, value);
     }
 
+    private bool _shouldInjectLanguageSpecificAudioStreams = true;
+    public bool ShouldInjectLanguageSpecificAudioStreams
+    {
+        get => _shouldInjectLanguageSpecificAudioStreams;
+        set => SetProperty(ref _shouldInjectLanguageSpecificAudioStreams, value);
+    }
+
     private bool _shouldInjectSubtitles = true;
     public bool ShouldInjectSubtitles
     {

YoutubeDownloader/ViewModels/Components/DashboardViewModel.cs

@@ -104,6 +104,7 @@ private async void EnqueueDownload(DownloadViewModel download, int position = 0)
                 ?? await downloader.GetBestDownloadOptionAsync(
                     download.Video!.Id,
                     download.DownloadPreference!,
+                    _settingsService.ShouldInjectLanguageSpecificAudioStreams,
                     download.CancellationToken
                 );
 
@@ -190,7 +191,10 @@ private async Task ProcessQueryAsync()
             if (result.Videos.Count == 1)
             {
                 var video = result.Videos.Single();
-                var downloadOptions = await downloader.GetDownloadOptionsAsync(video.Id);
+                var downloadOptions = await downloader.GetDownloadOptionsAsync(
+                    video.Id,
+                    _settingsService.ShouldInjectLanguageSpecificAudioStreams
+                );
 
                 var download = await _dialogManager.ShowDialogAsync(
                     _viewModelManager.CreateDownloadSingleSetupViewModel(video, downloadOptions)

YoutubeDownloader/ViewModels/Dialogs/SettingsViewModel.cs

@@ -40,6 +40,12 @@ public bool IsAuthPersisted
         set => _settingsService.IsAuthPersisted = value;
     }
 
+    public bool ShouldInjectLanguageSpecificAudioStreams
+    {
+        get => _settingsService.ShouldInjectLanguageSpecificAudioStreams;
+        set => _settingsService.ShouldInjectLanguageSpecificAudioStreams = value;
+    }
+
     public bool ShouldInjectSubtitles
     {
         get => _settingsService.ShouldInjectSubtitles;

YoutubeDownloader/Views/Dialogs/SettingsView.axaml

@@ -70,11 +70,20 @@
                             IsChecked="{Binding IsAuthPersisted}" />
                     </DockPanel>
 
+                    <!--  Inject language-specific audio streams  -->
+                    <DockPanel
+                        Margin="16,8"
+                        LastChildFill="False"
+                        ToolTip.Tip="Inject audio tracks in alternative languages (if available) into downloaded files">
+                        <TextBlock DockPanel.Dock="Left" Text="Inject alternative languages" />
+                        <ToggleSwitch DockPanel.Dock="Right" IsChecked="{Binding ShouldInjectLanguageSpecificAudioStreams}" />
+                    </DockPanel>
+
                     <!--  Inject subtitles  -->
                     <DockPanel
                         Margin="16,8"
                         LastChildFill="False"
-                        ToolTip.Tip="Inject subtitles into downloaded files">
+                        ToolTip.Tip="Inject subtitles (if available) into downloaded files">
                         <TextBlock DockPanel.Dock="Left" Text="Inject subtitles" />
                         <ToggleSwitch DockPanel.Dock="Right" IsChecked="{Binding ShouldInjectSubtitles}" />
                     </DockPanel>
@@ -83,7 +92,7 @@
                     <DockPanel
                         Margin="16,8"
                         LastChildFill="False"
-                        ToolTip.Tip="Inject media tags into downloaded files">
+                        ToolTip.Tip="Inject media tags (if available) into downloaded files">
                         <TextBlock DockPanel.Dock="Left" Text="Inject media tags" />
                         <ToggleSwitch DockPanel.Dock="Right" IsChecked="{Binding ShouldInjectTags}" />
                     </DockPanel>