我正在为Android开发基于ExoPlayer的媒体播放器,并且正在尝试编写自己的均衡器。
我已经对ExoPlayer进行了相当深入的研究,并且我相信最好的操作样本以应用Equalier更改的地方是自定义AudioProcessor
。
我以ChannelMappingAudioProcessor
为起点,并克隆了我认为相关的方面:
class EqualizerAudioProcessor : BaseAudioProcessor() {
private lateinit var outputChannels: IntArray
override fun configure(sampleRateHz: Int,channelCount: Int,encoding: Int): Boolean {
outputChannels = IntArray(channelCount)
for (i in 0 until channelCount) {
outputChannels[i] = i
}
return true
}
override fun isactive(): Boolean {
return true
}
override fun getOutputChannelCount(): Int {
return outputChannels.size
}
override fun queueInput(inputBuffer: ByteBuffer) {
var position = inputBuffer.position()
val limit = inputBuffer.limit()
val frameCount = (limit - position) / (2 * channelCount)
val outputSize = frameCount * outputChannels.size * 2
val buffer = replaceOutputBuffer(outputSize)
while (position < limit) {
for (element in outputChannels) {
var sample = inputBuffer.getShort(position + 2 * element)
// Todo: Manipulate sample
buffer.putShort(sample)
}
position += channelCount * 2
}
inputBuffer.position(limit)
buffer.flip()
}
override fun onReset() {
}
}
如果我enable
这个AudioProcessor
,似乎不会发生播放(它似乎停留在“暂停状态”,就像没有传递样本一样,有趣的是, queueInput()
没有被调用。如果我禁用了AudioProcessor
,则播放正常。
我希望有人可以帮助我了解我在这里是否出错以及如何使它工作。
作为参考,ExoPlayer实例的初始化方式如下:
private fun initPlayer(context: Context): ExoPlayer {
val audioProcessor = EqualizerAudioProcessor()
val renderersFactory = object : DefaultRenderersFactory(context) {
override fun buildAudioProcessors(): Array<AudioProcessor> {
return arrayOf(audioProcessor)
}
}
val player: SimpleExoPlayer = ExoPlayerFactory.newSimpleInstance(
context,renderersFactory,DefaultTrackSelector(),DefaultLoadControl()
)
player.addListener(object : Player.EventListener {
override fun onPlayerStateChanged(playWhenReady: Boolean,playbackState: Int) {
callback?.onPlayStateChanged(playWhenReady)
}
})
return player
}
预先感谢