Question

我正在尝试编写一个教育应用程序，可以结合简单的波形并进行播放。 AudioTrack中有一个方法可以接受浮动数组（来自docs）：

     *     audioData the array that holds the data to write.
     *     The implementation does not clip for sample values within the nominal range
     *     [-1.0f, 1.0f], provided that all gains in the audio pipeline are
     *     less than or equal to unity (1.0f), and in the absence of post-processing effects
     *     that could add energy, such as reverb.  For the convenience of applications
     *     that compute samples using filters with non-unity gain,
     *     sample values +3 dB beyond the nominal range are permitted.
     *     However such values may eventually be limited or clipped, depending on various gains
     *     and later processing in the audio path.  Therefore applications are encouraged
     *     to provide samples values within the nominal range.

           public int write(@NonNull float[] audioData, ...)

我认为我应该在[-1.0f, 1.0f]之间使用浮点数生成复杂的正弦波时，我将它们中的两个加在一起，从而将范围扩大到[-2.0f, 2.0f] 我想我应该以某种方式 normalize 这个...

private fun playSound(frequency1: Float, frequency2: Float) {
        val sineWave = FloatArray(BUFFER_SIZE) //data array
        val period1 = SAMPLING_RATE / frequency1
        val period2 = SAMPLING_RATE / frequency2
        for (i in sineWave.indices) {
            sineWave[i] = Math.sin(Math.PI * i / period1).toFloat() +
                Math.sin(Math.PI * i / period2).toFloat()
        }
        player.setVolume(0.5f)
        player.write(sineWave, 0, sineWave.size, AudioTrack.WRITE_BLOCKING)
        player.play()
    }

我不确定这是否正确，因此在创建复杂的正弦波时需要帮助

更改正弦波的幅度以适合AudioTrack.write（array：FloatArray）方法

0 个答案: