处理“动态”音频(C#,WP7)

时间:2012-02-20 12:22:13

标签: c# .net windows-phone-7 audio

有没有办法,在C#中,在.NET上,“在运行中”处理音频?例如,如果我想在录制时评估音频AT的平均强度(为此,我需要持续几毫秒)。

1 个答案:

答案 0 :(得分:17)

麦克风的初始化和录制的声音处理:

private void Initialize()
{
    Microphone microphone = Microphone.Default;
    // 100 ms is a minimum buffer duration
    microphone.BufferDuration = TimeSpan.FromMilliseconds(100);  

    DispatcherTimer updateTimer = new DispatcherTimer()
    {
        Interval = TimeSpan.FromMilliseconds(0.1)
    };
    updateTimer.Tick += (s, e) =>
    {
        FrameworkDispatcher.Update();
    };
    updateTimer.Start();

    byte[] microphoneSignal = new byte[microphone.GetSampleSizeInBytes(microphone.BufferDuration)];
    microphone.BufferReady += (s, e) =>
    {
        int microphoneDataSize = microphone.GetData(microphoneSignal);
        double amplitude = GetSignalAmplitude(microphoneSignal);
        // do your stuff with amplitude here
    };
    microphone.Start();
}

整体信号的幅度。您可以找到不在所有字节数组中的平均值,但在较小的窗口中可以获得幅度曲线:

private double GetSignalAmplitude(byte[] signal)
{
    int BytesInSample = 2;

    int signalSize = signal.Length / BytesInSample;

    double Sum = 0.0;

    for (int i = 0; i < signalSize; i++)
    {
        int sample = Math.Abs(BitConverter.ToInt16(signal, i * BytesInSample));
        Sum += sample;
    }            

    double amplitude = Sum / signalSize; 

    return amplitude;
}

用于即时生成声音的其他内容可能会帮助您:

DynamicSoundEffectInstance generatedSound = new DynamicSoundEffectInstance(SampleRate, AudioChannels.Mono);
generatedSound.SubmitBuffer(buffer);

private void Int16ToTwoBytes(byte[] output, Int16 value, int offset)
{
    output[offset + 1] = (byte)(value >> 8);
    output[offset] = (byte)(value & 0x00FF);
}