fix(vlc): add audio transcoding mode to fix 7.1 TrueHD playback

utils/profiles/native.js

@@ -7,12 +7,23 @@ import { Platform } from "react-native";
 import MediaTypes from "../../constants/MediaTypes";
 import { getSubtitleProfiles } from "./subtitles";
 
+/**
+ * @typedef {"ios" | "android"} PlatformType
+ * @typedef {"vlc" | "ksplayer"} PlayerType
+ * @typedef {"auto" | "stereo" | "5.1" | "passthrough"} AudioTranscodeModeType
+ *
+ * @typedef {Object} ProfileOptions
+ * @property {PlatformType} [platform] - Target platform
+ * @property {PlayerType} [player] - Video player being used
+ * @property {AudioTranscodeModeType} [audioMode] - Audio transcoding mode
+ */
+
 /**
  * Audio profiles for react-native-track-player based on platform capabilities.
  * iOS uses AVPlayer, Android uses ExoPlayer - each has different codec support.
  */
-const getAudioDirectPlayProfile = () => {
-  if (Platform.OS === "ios") {
+const getAudioDirectPlayProfile = (platform) => {
+  if (platform === "ios") {
     // iOS AVPlayer supported formats
     return {
       Type: MediaTypes.Audio,
@@ -29,8 +40,8 @@ const getAudioDirectPlayProfile = () => {
   };
 };
 
-const getAudioCodecProfile = () => {
-  if (Platform.OS === "ios") {
+const getAudioCodecProfile = (platform) => {
+  if (platform === "ios") {
     // iOS AVPlayer codec constraints
     return {
       Type: MediaTypes.Audio,
@@ -45,12 +56,99 @@ const getAudioCodecProfile = () => {
   };
 };
 
-export const generateDeviceProfile = () => {
+/**
+ * Gets the video audio codec configuration based on platform, player, and audio mode.
+ *
+ * Key insight: VLC handles AC3/EAC3/DTS downmixing fine.
+ * Only TrueHD and DTS-HD MA (lossless 7.1) cause issues on mobile devices
+ * because VLC's internal downmixing from 7.1 to stereo fails on some Android audio pipelines.
+ *
+ * @param {PlatformType} platform
+ * @param {PlayerType} player
+ * @param {AudioTranscodeModeType} audioMode
+ * @returns {{ directPlayCodec: string, maxAudioChannels: string }}
+ */
+const getVideoAudioCodecs = (platform, player, audioMode) => {
+  // Base codecs that work everywhere
+  const baseCodecs = "aac,mp3,flac,opus,vorbis";
+
+  // Surround codecs that VLC handles well (downmixes properly)
+  const surroundCodecs = "ac3,eac3,dts";
+
+  // Lossless HD codecs that cause issues with VLC's downmixing on mobile
+  const losslessHdCodecs = "truehd";
+
+  // Platform-specific codecs
+  const platformCodecs = platform === "ios" ? "alac,wma" : "wma";
+
+  // Handle explicit user settings first
+  switch (audioMode) {
+    case "stereo":
+      // Force stereo transcoding - only allow basic codecs
+      return {
+        directPlayCodec: `${baseCodecs},${platformCodecs}`,
+        maxAudioChannels: "2",
+      };
+
+    case "5.1":
+      // Allow up to 5.1 - include surround codecs but not lossless HD
+      return {
+        directPlayCodec: `${baseCodecs},${surroundCodecs},${platformCodecs}`,
+        maxAudioChannels: "6",
+      };
+
+    case "passthrough":
+      // Allow all codecs - for users with external DAC/receiver
+      return {
+        directPlayCodec: `${baseCodecs},${surroundCodecs},${losslessHdCodecs},${platformCodecs}`,
+        maxAudioChannels: "8",
+      };
+    default:
+      // Auto mode: platform and player-specific defaults
+      break;
+  }
+
+  // Auto mode logic based on platform and player
+  if (player === "ksplayer" && platform === "ios") {
+    // KSPlayer on iOS handles all codecs well, including TrueHD
+    return {
+      directPlayCodec: `${baseCodecs},${surroundCodecs},${losslessHdCodecs},${platformCodecs}`,
+      maxAudioChannels: "8",
+    };
+  }
+
+  // VLC on Android or iOS - don't include TrueHD (causes 7.1 downmix issues)
+  // DTS core is fine, VLC handles it well. Only lossless 7.1 formats are problematic.
+  return {
+    directPlayCodec: `${baseCodecs},${surroundCodecs},${platformCodecs}`,
+    maxAudioChannels: "6",
+  };
+};
+
+/**
+ * Generates a device profile for Jellyfin playback.
+ *
+ * @param {ProfileOptions} [options] - Profile configuration options
+ * @returns {Object} Jellyfin device profile
+ */
+export const generateDeviceProfile = (options = {}) => {
+  const platform = options.platform || Platform.OS;
+  const player = options.player || "vlc";
+  const audioMode = options.audioMode || "auto";
+
+  const { directPlayCodec, maxAudioChannels } = getVideoAudioCodecs(
+    platform,
+    player,
+    audioMode,
+  );
+
+  const playerName = player === "ksplayer" ? "KSPlayer" : "VLC Player";
+
   /**
    * Device profile for Native video player
    */
   const profile = {
-    Name: `1. MPV Player`,
+    Name: `1. ${playerName}`,
     MaxStaticBitrate: 999_999_999,
     MaxStreamingBitrate: 999_999_999,
     CodecProfiles: [
@@ -76,7 +174,7 @@ export const generateDeviceProfile = () => {
           },
         ],
       },
-      getAudioCodecProfile(),
+      getAudioCodecProfile(platform),
     ],
     DirectPlayProfiles: [
       {
@@ -84,9 +182,9 @@ export const generateDeviceProfile = () => {
         Container: "mp4,mkv,avi,mov,flv,ts,m2ts,webm,ogv,3gp,hls",
         VideoCodec:
           "h264,hevc,mpeg4,divx,xvid,wmv,vc1,vp8,vp9,av1,avi,mpeg,mpeg2video",
-        AudioCodec: "aac,ac3,eac3,mp3,flac,alac,opus,vorbis,wma,dts,truehd",
+        AudioCodec: directPlayCodec,
       },
-      getAudioDirectPlayProfile(),
+      getAudioDirectPlayProfile(platform),
     ],
     TranscodingProfiles: [
       {
@@ -96,6 +194,7 @@ export const generateDeviceProfile = () => {
         Container: "ts",
         VideoCodec: "h264, hevc",
         AudioCodec: "aac,mp3,ac3,dts",
+        MaxAudioChannels: maxAudioChannels,
       },
       {
         Type: MediaTypes.Audio,