Add ass/ssa subtitle support (#2136)

* Add ass/ssa subtitle support

Create renderers factory using constructor

Init libass when exoPlayerDirectPlayAss is true

Replace MediaSource.Factory singleton with factory

Fix linter errors

* Update SSA/ASS direct play description

app/build.gradle.kts

@@ -172,6 +172,7 @@ dependencies {
     implementation(libs.bundles.androidx.media3)
     proprietaryImplementation(libs.androidx.media3.cast)
     proprietaryImplementation(libs.bundles.playservices)
+    implementation(libs.libass.media)
 
     // Room
     implementation(libs.bundles.androidx.room)

app/src/main/java/org/jellyfin/mobile/app/AppModule.kt

@@ -14,15 +14,16 @@ import androidx.media3.datasource.cache.Cache
 import androidx.media3.datasource.cache.CacheDataSource
 import androidx.media3.datasource.cache.NoOpCacheEvictor
 import androidx.media3.datasource.cache.SimpleCache
-import androidx.media3.exoplayer.hls.HlsMediaSource
 import androidx.media3.exoplayer.source.DefaultMediaSourceFactory
 import androidx.media3.exoplayer.source.MediaSource
-import androidx.media3.exoplayer.source.ProgressiveMediaSource
-import androidx.media3.exoplayer.source.SingleSampleMediaSource
 import androidx.media3.extractor.DefaultExtractorsFactory
 import androidx.media3.extractor.ts.TsExtractor
 import androidx.work.WorkManager
 import coil3.ImageLoader
+import io.github.peerless2012.ass.media.AssHandler
+import io.github.peerless2012.ass.media.kt.withAssMkvSupport
+import io.github.peerless2012.ass.media.parser.AssSubtitleParserFactory
+import io.github.peerless2012.ass.media.type.AssRenderType
 import kotlinx.coroutines.channels.Channel
 import okhttp3.OkHttpClient
 import org.jellyfin.mobile.MainViewModel
@@ -68,6 +69,7 @@ val applicationModule = module {
     single { RemoteVolumeProvider(get()) }
     single(named(PLAYER_EVENT_CHANNEL)) { Channel<PlayerEvent>() }
     factory { WorkManager.getInstance(get()) }
+    single { AssHandler(AssRenderType.OVERLAY_OPEN_GL) }
 
     // Controllers
     single { ApiClientController(get(), get(), get(), get(), get()) }
@@ -155,7 +157,7 @@ val applicationModule = module {
             }
     }
 
-    single<MediaSource.Factory> {
+    factory<MediaSource.Factory> {
         val context: Context = get()
         val extractorsFactory = DefaultExtractorsFactory().apply {
             // https://github.com/google/ExoPlayer/issues/8571
@@ -166,8 +168,18 @@ val applicationModule = module {
                 },
             )
         }
+
+        val appPreferences: AppPreferences = get()
+        if (appPreferences.exoPlayerDirectPlayAss) {
+            val assHandler: AssHandler = get()
+            val assSubtitleParserFactory = AssSubtitleParserFactory(assHandler)
+            val assExtractorsFactory = extractorsFactory.withAssMkvSupport(assSubtitleParserFactory, assHandler)
+            DefaultMediaSourceFactory(get<CacheDataSource.Factory>(), assExtractorsFactory)
+                .setSubtitleParserFactory(assSubtitleParserFactory)
+        } else {
             DefaultMediaSourceFactory(get<CacheDataSource.Factory>(), extractorsFactory)
         }
+    }
 
     single(createdAtStart = true) { StorageManager(get(), get()) }
     single { DownloadManager(get(), get(), get(), get(), get()) }

app/src/main/java/org/jellyfin/mobile/player/PlayerViewModel.kt

@@ -27,6 +27,8 @@ import androidx.media3.exoplayer.mediacodec.MediaCodecSelector
 import androidx.media3.exoplayer.source.MediaSource
 import androidx.media3.exoplayer.trackselection.DefaultTrackSelector
 import androidx.media3.exoplayer.util.EventLogger
+import io.github.peerless2012.ass.media.AssHandler
+import io.github.peerless2012.ass.media.factory.AssRenderersFactory
 import kotlinx.coroutines.CoroutineScope
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.Job
@@ -239,6 +241,7 @@ class PlayerViewModel(application: Application) : AndroidViewModel(application),
                 .build()
             else -> DefaultLoadControl()
         }
+        val appPreferences: AppPreferences = get()
         val renderersFactory = DefaultRenderersFactory(getApplication()).apply {
             setEnableDecoderFallback(true) // Fallback only works if initialization fails, not decoding at playback time
             val rendererMode = when {
@@ -272,7 +275,7 @@ class PlayerViewModel(application: Application) : AndroidViewModel(application),
 
                 filteredDecoderList
             }
-        }
+        }.let { if (appPreferences.exoPlayerDirectPlayAss) AssRenderersFactory(get(), it) else it }
         _player.value = ExoPlayer.Builder(getApplication(), renderersFactory, get()).apply {
             setUsePlatformDiagnostics(false)
             setTrackSelector(trackSelector)
@@ -282,6 +285,7 @@ class PlayerViewModel(application: Application) : AndroidViewModel(application),
         }.build().apply {
             addListener(this@PlayerViewModel)
             applyDefaultAudioAttributes(C.AUDIO_CONTENT_TYPE_MOVIE)
+            if (appPreferences.exoPlayerDirectPlayAss) get<AssHandler>().init(this)
         }
     }
 

app/src/main/java/org/jellyfin/mobile/player/ui/PlayerFragment.kt

@@ -27,6 +27,8 @@ import androidx.fragment.app.viewModels
 import androidx.lifecycle.lifecycleScope
 import androidx.media3.common.Player
 import androidx.media3.ui.PlayerView
+import io.github.peerless2012.ass.media.AssHandler
+import io.github.peerless2012.ass.media.widget.AssSubtitleView
 import kotlinx.coroutines.Job
 import kotlinx.coroutines.launch
 import org.jellyfin.mobile.R
@@ -59,6 +61,7 @@ import androidx.media3.ui.R as Media3R
 @Suppress("TooManyFunctions")
 class PlayerFragment : Fragment(), BackPressInterceptor {
     private val appPreferences: AppPreferences by inject()
+    private val assHandler: AssHandler by inject()
     private val viewModel: PlayerViewModel by viewModels()
     private var _playerBinding: FragmentPlayerBinding? = null
     private val playerBinding: FragmentPlayerBinding get() = _playerBinding!!
@@ -209,6 +212,12 @@ class PlayerFragment : Fragment(), BackPressInterceptor {
         // Disable controller animations
         playerView.setControllerAnimationEnabled(false)
 
+        if (appPreferences.exoPlayerDirectPlayAss) {
+            playerView.subtitleView?.apply {
+                addView(AssSubtitleView(this.context, assHandler))
+            }
+        }
+
         playerLockScreenHelper = PlayerLockScreenHelper(this, playerBinding, orientationListener)
         playerGestureHelper = PlayerGestureHelper(this, playerBinding, playerLockScreenHelper)
 

app/src/main/java/org/jellyfin/mobile/settings/SettingsFragment.kt

@@ -170,7 +170,7 @@ class SettingsFragment : Fragment(), BackPressInterceptor {
         }
         directPlayAssPreference = checkBox(Constants.PREF_EXOPLAYER_DIRECT_PLAY_ASS) {
             titleRes = R.string.pref_exoplayer_direct_play_ass
-            summaryRes = R.string.pref_exoplayer_direct_play_ass_summary
+            summaryRes = R.string.pref_exoplayer_direct_play_ass_description
             enabled = appPreferences.videoPlayerType == VideoPlayerType.EXO_PLAYER
         }
         val networkBufferOptions = listOf(

app/src/main/res/values/strings.xml

@@ -111,7 +111,7 @@
     <string name="pref_exoplayer_allow_horizontal_gesture">Horizontal gestures</string>
     <string name="pref_exoplayer_allow_horizontal_gesture_summary">Allow horizontal gesture control for video seeking</string>
     <string name="pref_exoplayer_direct_play_ass">Allow SSA/ASS subtitles in direct play</string>
-    <string name="pref_exoplayer_direct_play_ass_summary">Prevent transcoding and show subtitles with basic styling only. Advanced subtitle styling will not be available if enabled.</string>
+    <string name="pref_exoplayer_direct_play_ass_description">Use experimental client-side subtitle rendering, may not always work</string>
     <string name="pref_exoplayer_network_buffer">Playback buffer size</string>
     <string name="network_buffer_auto">Auto</string>
     <string name="network_buffer_auto_description">Default buffer, suitable for most playback scenarios</string>

gradle/libs.versions.toml

@@ -52,6 +52,7 @@ androidx-mediarouter = "1.8.1"
 androidx-media3 = "1.11.0"
 jellyfin-androidx-media = "1.9.0+1"
 playservices = "22.3.1"
+libass-media = "0.5.1"
 
 # Room
 androidx-room = "2.8.4"
@@ -138,6 +139,7 @@ androidx-media3-cast = { module = "androidx.media3:media3-cast", version.ref = "
 playservices-cast = { group = "com.google.android.gms", name = "play-services-cast", version.ref = "playservices" }
 playservices-castframework = { group = "com.google.android.gms", name = "play-services-cast-framework", version.ref = "playservices" }
 jellyfin-androidx-media3-ffmpeg-decoder = { module = "org.jellyfin.media3:media3-ffmpeg-decoder", version.ref = "jellyfin-androidx-media" }
+libass-media = { module = "io.github.peerless2012:ass-media", version.ref = "libass-media" }
 
 # Room
 androidx-room-runtime = { group = "androidx.room", name = "room-runtime", version.ref = "androidx-room" }