Easy Visualizer with ExoPlayer

OK, lets get started.

Add the latest version of the Exoplayer into your application. I am using ‘2.10.3’ for this simple demo.

Create new class called RendererFactory.kt

import android.content.Context
import android.os.Handler
import com.google.android.exoplayer2.DefaultRenderersFactory
import com.google.android.exoplayer2.Renderer
import com.google.android.exoplayer2.audio.AudioProcessor
import com.google.android.exoplayer2.audio.AudioRendererEventListener
import com.google.android.exoplayer2.audio.TeeAudioProcessor
import com.google.android.exoplayer2.drm.DrmSessionManager
import com.google.android.exoplayer2.drm.FrameworkMediaCrypto
import com.google.android.exoplayer2.mediacodec.MediaCodecSelector
import java.util.*
class RendererFactory(context: Context, var listener: TeeAudioProcessor.AudioBufferSink) :
    DefaultRenderersFactory(context) {
override fun buildAudioRenderers(
    context: Context?,
    extensionRendererMode: Int,
    mediaCodecSelector: MediaCodecSelector?,
    drmSessionManager: DrmSessionManager<FrameworkMediaCrypto>?,
    playClearSamplesWithoutKeys: Boolean,
    enableDecoderFallback: Boolean,
    audioProcessors: Array<out AudioProcessor>?,
    eventHandler: Handler?,
    eventListener: AudioRendererEventListener?,
    out: ArrayList<Renderer>?
) {

    val audioProcessor = Array<AudioProcessor>(1) {
        TeeAudioProcessor(listener)
    }

    super.buildAudioRenderers(
        context,
        extensionRendererMode,
        mediaCodecSelector,
        drmSessionManager,
        playClearSamplesWithoutKeys,
        enableDecoderFallback,
        audioProcessor,
        eventHandler,
        eventListener,
        out
    )
}

Now, while creating the ExoPlayer instance set the renderer factory .

// create default track selector
val trackSelector = DefaultTrackSelector()

// create default load control with increase buffer size
val loadControl = PlayerHelper.getLoadController(10)
var rendererFactory = RendererFactory(this, object : TeeAudioProcessor.AudioBufferSink {
    override fun flush(sampleRateHz: Int, channelCount: Int, encoding: Int) {
Timber.d("Sample Rate: $sampleRateHz channelCount: $channelCount and encoding; $encoding")
 
   }

    override fun handleBuffer(buffer: ByteBuffer?) {
          // Apply fft &
          // pass the buffer data to your visualizer.
      
   }

})

val player = ExoPlayerFactory.newSimpleInstance(this, rendererFactory, trackSelector, loadControl)

That’s it. :)