如何播放 opus 解码帧，或将 1 字节 pcm16 拆分为 2 字节 pcm？

Question

在录制麦克风时，录制的块是原始的PCM8格式，我能够通过更改bitDepthInBytes = 2来发送它并播放它而没有任何噪音，但是当我通过网络发送编码的opus帧并将它们解码为PCM16时，除非我将它们转换为PCM8，否则我无法播放它们，但它很嘈杂。这是我的代码：

const sampleRate = 48000

const channels = 1

....

....

    dec, err := opus.NewDecoder(sampleRate, channels)

    if err != nil {

        fmt.Println(err)

        return

    }

    var frameSizeMs float32 = 20

    frameSize := int(channels * frameSizeMs * sampleRate / 1000)

    pcm := make([]int16, frameSize)

    // (sampleRate int, channelNum int, bitDepthInBytes int, bufferSizeInBytes int)

    context, err := oto.NewContext(sampleRate, channels, 1, frameSize*2)

    if err != nil {

        log.Fatal(err)

    }

    player := context.NewPlayer()

    ...

    ...

    _, err := dec.Decode(data, pcm)

    if err != nil {

        fmt.Println(err)

    }

    var mask uint16 = 0x8000

    pcm8 := make([]byte, frameSize)

    for i := 0; i < frameSize; i++ {

        // using this work and play sound but it has noise

        pcm8[i] = byte((uint16(pcm[i]) ^ mask) >> 8)

    }

    

    _, _ = player.Write(pcm8)

Answer 1

通过阅读本文，我能够知道如何将PCM缓冲区格式化为可播放的音频字节 https://github.com/philfrei/AudioCue/blob/master/src/main/java/com/adonax/audiocue/AudioCue.java，这是我使用的片段：public static byte[] fromBufferToAudioBytes(byte[] audioBytes, float[] buffer){&nbsp; &nbsp; for (int i = 0, n = buffer.length; i < n; i++)&nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; buffer[i] *= 32767;&nbsp; &nbsp; &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; &nbsp; audioBytes[i*2] = (byte) buffer[i];&nbsp; &nbsp; &nbsp; &nbsp; audioBytes[i*2 + 1] = (byte)((int)buffer[i] >> 8 );&nbsp; &nbsp; }&nbsp; &nbsp;&nbsp;&nbsp; &nbsp; return audioBytes;}这是我在代码中更新的内容&nbsp; &nbsp; pcm8 := make([]byte, frameSize * 2)&nbsp; &nbsp; for i := 0; i < frameSize; i++ {&nbsp; &nbsp; &nbsp; &nbsp; //pcm[i] *= 32767 // uncomment when pcm array is float insteand of int16&nbsp; &nbsp; &nbsp; &nbsp; pcm8[i*2] =&nbsp; byte(uint16(pcm[i]))&nbsp; &nbsp; &nbsp; &nbsp; pcm8[i*2 + 1] = byte(uint16(pcm[i]) >> 8)&nbsp; &nbsp; }