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Android library which can interact with ReaStream.

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libReaStream

Android audio streaming library which can interact with ReaStream.

Receive audio/MIDI from REAPER

val audioData = FloatArray(ReaStreamPacket.MAX_BLOCK_LENGTH * 2) // Make an array for audio of sufficient size

val packets = receiveReaStream()
packets.collect { packet ->
    if (packet.isAudio) {
        val audioDataLength = packet.readAudio(audioData)
        // audioData[0 until audioDataLength] is filled.
        // handle audio samples
    } else if (packet.isMidi) {
        packet.midiEvents.forEach { midiEvent ->
            // handle MIDI event
        }
    }
}

Simply use AudioTrackOutput to play received audio.

receiveReaStream().play(sampleRate = 48000) // sampleRate must be equal to input audio

If you want to play audio and process MIDI at the same time, use SharedFlow.

coroutineScope {
    val packets = receiveReaStream().shareIn(this, SharingStarted.WhileSubscribed())
    launch {
        packets.play(sampleRate = 48000)
    }
    launch {
        packets.filter { it.isMidi }
            .collect { packet ->
                packet.midiEvents.forEach { midiEvent ->
                    // handle MIDI event
                }
            }
    }
}

Send audio/MIDI to REAPER

val sampleRate = 48000 // Usually 44100 or 48000 is good choice.
val channels = 2       // Only 1 or 2 are currently supported.
val sender = ReaStreamSender(
    identifier = "default",      // Must be the same as REAPER
    sampleRate = sampleRate,     // Input audio sample rate.
    channels = channels,         // Input audio channels.
    remoteHost = "192.168.10.2", // IP address of Mac/PC which is running REAPER
)

// send MIDI
val data = byteArrayOf(0x90.toByte(), 60, 127)
sender.send(data)

// or something like
sender.send(midiData(MidiCommand.NoteOn, channel, noteNumber, velocity))
sender.send(midiData(MidiCommand.NoteOff, channel, noteNumber, velocity))

// send audio
val input = AudioRecordInput(
    sampleRate = sampleRate,
    channels = channels,
)
input.readAudio()
    // ReaStream uses non-interleaved arrangement.
    // De-interleaving is required if channels is more than 1.
    .map { it.deInterleave(channels = channels) }
    .collect { audioData ->
        sender.send(audioData)
    }

How to use example app

  1. Launch REAPER.
  2. Add track in REAPER.
  3. Add ReaStream to track.
  4. Build app module and launch it in Android.

and...

Stream from REAPER to Android Stream from Android to REAPER
5. Set REAPER's ReaStream to Send audio/MIDI. Set REAPER's ReaStream to Receive audio/MIDI.
6. In Android app, choose Receive audio. In Android app, choose Send audio.
7. Enter Android device's IP address in REAPER's text field Enter REAPER machine's IP address in Android's text field.

How to use libreastream in your app

// app/build.gradle

repositories {
    google()
    maven { url 'https://jitpack.io' } // Add this
}


dependencies {
    implementation 'com.github.niusounds:libReaStream:0.2.0' // Add this
}