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我正在实现一个简单的录制、播放应用程序,它可以播放和录制 WAV 文件。
要求如下:

1) Windows 7、Visual Studio 2010(或 2012)、C#
2) 录制、播放带有规格信息的 Wav 文件:samplerate 22050、mono、bitspersample 16
3) 录制时可以显示微声级

使用 1) 和 2),我可以使用 lib (winmm.dll) 和 mciSendString(),如下所示

[DllImport("winmm.dll")]  
private static extern long mciSendString(string lpstrCommand, string lpstrReturnString, int uReturnLength, int hwndCallback);

// Open file to play
public void open(string file)
{
    string command = "open \"" + file + "\" type waveaudio  alias MyWav";
    mciSendString(command, null, 0, 0);
}

// Start playing
public void play()
{
    string command = "play MyWav";
    mciSendString(command, null, 0, 0);
}

// Stop playing
public void stop()
{
    string command = "stop MyWav";
    mciSendString(command, null, 0, 0);

    command = "close MyWav";
    mciSendString(command, null, 0, 0);
}

// Start recording
public void record()
{
   string command = "open new Type waveaudio Alias MyRec";
    mciSendString(command, "", 0, 0);

    command = "set capture time format ms bitspersample 16 channels 1 samplespersec 22050 alignment 4";
    mciSendString(command, "", 0, 0);

    command = "record MyRec";
    mciSendString(command, "", 0, 0);
}

// Stop recording
public void stoprec()
{
    string fileName = @"""D:\Rec1.wav""";

    string command = "stop MyRec";
    mciSendString(command, "", 0, 0);

    command = @"save MyRec " + fileName;

    Debug.WriteLine(command);
    mciSendString(command, "", 0, 0);

    command = "close MyRec";
    mciSendString(command, "", 0, 0);
}

对于 3),我还想使用 mciSendString。我找到了以下命令(状态):

string command = "status MyRec level ";
long mci_ret = mciSendString(command, "", 0, 0);

但我不知道从上面的命令中获取音量,谁能告诉我方法?

参考:来自 mciSendString() 的状态命令可在 Microsoft 文档中找到:http: //msdn.microsoft.com/en-us/library/windows/desktop/dd798683%28v=vs.85%29.aspx
它说:级别:返回当前 PCM 音频样本值。

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1 回答 1

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我通过打开两个设备来监控级别,一个用于录制/播放(track1),一个用于获取级别(waveLevel)。以下是在foxpro中。

* OPEN WAVE DEVICE FOR LEVEL READINGS 
= mciSendString("open new type waveaudio alias waveLevel", '0&', 0, 0) 

* START RECORDING
= mciSendString("open new type waveaudio alias track1", '0&', 0, 0)

然后要获得 track1 的级别,我使用 waveLevel 设备

= mciSendString("status waveLevel level", @cBuff, LEN(cBuff) ,0)
于 2013-05-07T18:01:17.260 回答