波形文件的时间长度

Length in time of a wave file

我有一些使用 TTS 生成 wave 文件然后播放的简单代码:

public void TestSpeech()
{
    SpeechSynthesizer synth = new SpeechSynthesizer();
    using (MemoryStream stream = new MemoryStream())
    {
        synth.SetOutputToWaveStream(stream);
        synth.Speak("Hello world");
        stream.Seek(0, SeekOrigin.Begin);
        IWaveSource source = new WaveFileReader(stream);
        EventWaitHandle waitHandle = new EventWaitHandle(false, EventResetMode.AutoReset);
        var soundOut = new WasapiOut();
        soundOut.Initialize(source);
        soundOut.Stopped += (s, e) => waitHandle.Set();
        soundOut.Play();
        waitHandle.WaitOne();
        soundOut.Dispose();
        source.Dispose();
    }
}

一切正常,但我想在开始播放波形文件之前知道它会持续多长时间。是否有某种计算方法,或者在某处可用?

如果某处可用,它是如何计算的?我假设它与流中的数据量有关,但如何?

您可以使用 CSCore or NAudio:

CSCore(摘自this sample, current playback position and total duration are used here):

using System;
using CSCore;
using CSCore.Codecs.WAV;

IWaveSource wavSource = new WaveFileReader(stream);
TimeSpan totalTime = wavSource.GetLength();

NAudio:

using System;
using NAudio.Wave;

using (var wfr = new WaveFileReader(stream))
{
    TimeSpan totalTime = wfr.TotalTime;
}

另见 the MSDN docs for TimeSpan

持续时间是根据 WAVE 数据的总长度(可以是压缩文件的估计值)和每秒平均字节数(根据 属性 中的 NAudio source TotalTime):

totalTimeInSeconds = LengthInBytes / AverageBytesPerSecond;
using CSCore;

IWaveSource waveSource = new WaveFileReader(stream);
TimeSpan totalTime = waveSource.GetLength( ); //get length returns a timespan

如果有人正在寻找解决方法,我会这样处理: (请原谅我的第一个 Whosebug 评论)

  1. 我创建了 bool mouseScrewsAround = false
  2. 计时器事件,在播放时改变 trackBar 的位置,仅在 !mouseScrewsAround
  3. 时触发
  4. trackBar_MouseDown -> mouseScrewsAround = true
  5. trackBar_MouseUp -> 改变轨道位置,然后 mouseScrewsAround = false