pepsi1978/android-audio

Android Audio Skill — Professional Sound Integration

Step 1: Choose the Right API

Ask the user what kind of audio they need, then recommend:

| Need | API | Kotlin/C++ | Latency | |------|-----|------------|---------| | Short UI sounds (clicks, alerts, game effects < 5s) | SoundPool | Pure Kotlin | ~50ms | | Music, podcasts, streaming, long audio | Jetpack Media3 | Pure Kotlin | ~100ms | | Real-time audio, instruments, games requiring < 20ms | Oboe | C++ (NDK) + Kotlin JNI | < 20ms | | Procedural/generated sounds (synthesis, DSP) | TarsosDSP or MWEngine | Kotlin / C++ | Variable | | 3D spatial audio (headphones, XR) | Spatializer API (API 32+) | Pure Kotlin | ~50ms | | Audio synced with haptic vibration | HapticGenerator (API 31+) | Pure Kotlin | Synced |

Step 2: Generate Dependencies

Based on the chosen API, add these to build.gradle.kts:

SoundPool (built-in, no dependency needed)

// SoundPool is part of Android SDK — no extra dependency
// Just use: import android.media.SoundPool

Jetpack Media3

val media3Version = "1.6.0"
dependencies {
    implementation("androidx.media3:media3-exoplayer:$media3Version")
    implementation("androidx.media3:media3-session:$media3Version")
    implementation("androidx.media3:media3-ui:$media3Version")
    implementation("androidx.media3:media3-common-ktx:$media3Version") // Kotlin Coroutines
}

Oboe (C++ NDK)

// build.gradle.kts
android {
    defaultConfig {
        externalNativeBuild {
            cmake {
                arguments("-DANDROID_STL=c++_static")
                cppFlags("-std=c++17")
            }
        }
    }
    externalNativeBuild {
        cmake { path = file("src/main/cpp/CMakeLists.txt") }
    }
}
dependencies {
    implementation("com.google.oboe:oboe:1.9.0")
}

TarsosDSP

repositories { maven { url = uri("https://jitpack.io") } }
dependencies {
    implementation("com.github.AkshayChordiya:TarsosDSP-Android:master-SNAPSHOT")
}

Step 3: Generate Boilerplate Code

SoundPool Manager (for short effects)

class SoundEffectManager(private val context: Context) {
    private val soundPool = SoundPool.Builder()
        .setMaxStreams(10)
        .setAudioAttributes(
            AudioAttributes.Builder()
                .setUsage(AudioAttributes.USAGE_GAME)
                .setContentType(AudioAttributes.CONTENT_TYPE_SONIFICATION)
                .build()
        ).build()

    private val sounds = mutableMapOf<String, Int>()

    fun load(name: String, resId: Int) {
        sounds[name] = soundPool.load(context, resId, 1)
    }

    fun play(name: String, volume: Float = 1.0f) {
        sounds[name]?.let { soundPool.play(it, volume, volume, 1, 0, 1.0f) }
    }

    fun release() = soundPool.release()
}

Media3 Player (for music/streaming)

@Composable
fun AudioPlayer(uri: String) {
    val context = LocalContext.current
    val player = remember {
        ExoPlayer.Builder(context).build().apply {
            setMediaItem(MediaItem.fromUri(uri))
            prepare()
        }
    }
    DisposableEffect(Unit) { onDispose { player.release() } }

    Row(verticalAlignment = Alignment.CenterVertically) {
        IconButton(onClick = {
            if (player.isPlaying) player.pause() else player.play()
        }) {
            Icon(
                if (player.isPlaying) Icons.Default.Pause else Icons.Default.PlayArrow,
                contentDescription = if (player.isPlaying) "Pause" else "Play"
            )
        }
    }
}

Step 4: Audio Format Recommendations

| Format | Best for | Size | Quality | Android since | |--------|----------|------|---------|---------------| | OGG Vorbis | Effects + Music | Small | Excellent | API 1 | | OGG Opus | Speech/Streaming | Very small | Excellent low-bitrate | API 21 | | WAV | Development only | Large | Lossless | API 1 | | FLAC | Hi-fi music apps | Medium | Lossless | API 12 |

Recommendation: Use OGG Vorbis at 128-192 kbps for everything. Better than MP3 at same bitrate.

Step 5: Audio Focus (MANDATORY for playback apps)

val audioManager = context.getSystemService(Context.AUDIO_SERVICE) as AudioManager
val focusRequest = AudioFocusRequest.Builder(AudioManager.AUDIOFOCUS_GAIN)
    .setAudioAttributes(AudioAttributes.Builder()
        .setUsage(AudioAttributes.USAGE_MEDIA)
        .build())
    .setOnAudioFocusChangeListener { focusChange ->
        when (focusChange) {
            AudioManager.AUDIOFOCUS_LOSS -> player.pause()
            AudioManager.AUDIOFOCUS_LOSS_TRANSIENT -> player.pause()
            AudioManager.AUDIOFOCUS_LOSS_TRANSIENT_CAN_DUCK -> player.setVolume(0.2f)
            AudioManager.AUDIOFOCUS_GAIN -> { player.setVolume(1.0f); player.play() }
        }
    }.build()
audioManager.requestAudioFocus(focusRequest)

Step 6: Free Sound Resources

| Source | License | Best for | |--------|---------|----------| | Zapsplat | Royalty-free | 160K+ sounds, app/game ready | | Freesound | CC (varies) | OGG downloads, community | | SONNISS GDC | Royalty-free, no attribution | Annual pro pack | | Mixkit | Royalty-free | Clean game sounds |

Sound Preview

To preview sounds on macOS before adding to your app:

# Play any audio file
afplay path/to/sound.ogg
afplay path/to/sound.wav
afplay path/to/sound.mp3

# Play with volume adjustment (0.0 to 1.0)
afplay -v 0.5 path/to/sound.ogg

# Play at different speed
afplay -r 1.5 path/to/sound.ogg  # 1.5x speed

For visual preview with waveform, open in QuickTime Player or use ffplay:

ffplay -nodisp path/to/sound.ogg  # Audio only, no window
ffplay -showmode 1 path/to/sound.ogg  # With waveform visualization

Proactive Sound Suggestions (MANDATORY)

When working on ANY Android app with UI interactions, ALWAYS proactively suggest sounds:

Sound-Moeglichkeiten fuer dein Projekt:

| Interaktion | Sound-Typ | Empfehlung | |-------------|-----------|------------| | Button-Taps | Kurzer Click (50-100ms) | SoundPool, OGG Vorbis | | Richtige Antwort | Aufsteigende Tonfolge | SoundPool + HapticFeedback | | Falsche Antwort | Kurzer Buzz/absteigend | SoundPool + VibrationEffect | | Timer/Countdown | Tick-Tock, Tempo steigernd | SoundPool mit Pitch-Variation | | Seitenwechsel | Sanfter Whoosh | SoundPool | | Achievement/Level-Up | Fanfare (1-2s) | Media3 oder SoundPool | | Hintergrundmusik | Loop, dezent | Media3 mit AudioFocus |

Soll ich passende Sounds auf Freesound suchen? Sag z.B. "suche einen Erfolgs-Sound"

After adding any sound to the project, ALWAYS offer to preview it:

Soll ich dir den Sound vorspielen? (afplay [path])

Use the sound-search skill for Freesound API integration when the user wants to search.