Waveform-Audio デバイスを使用した記録

次の例では、新しいファイルを含む波形オーディオ デバイスを開き、指定した時間のレコードを記録し、録音を再生し、必要に応じて録音を保存するようにユーザーに求めます。 mciSendCommand 関数を使用します。

// Uses the MCI_OPEN, MCI_RECORD, and MCI_SAVE commands to record and
// save a waveform-audio file. Returns 0L if successful; otherwise,
// it returns an MCI error code.

DWORD recordWAVEFile(DWORD dwMilliSeconds)
{
    UINT wDeviceID;
    DWORD dwReturn;
    MCI_OPEN_PARMS mciOpenParms;
    MCI_RECORD_PARMS mciRecordParms;
    MCI_SAVE_PARMS mciSaveParms;
    MCI_PLAY_PARMS mciPlayParms;

    // Open a waveform-audio device with a new file for recording.
    mciOpenParms.lpstrDeviceType = "waveaudio";
    mciOpenParms.lpstrElementName = "";
    if (dwReturn = mciSendCommand(0, MCI_OPEN,
        MCI_OPEN_ELEMENT | MCI_OPEN_TYPE, 
        (DWORD)(LPVOID) &mciOpenParms))
    {
        // Failed to open device; don't close it, just return error.
        return (dwReturn);
    }

    // The device opened successfully; get the device ID.
    wDeviceID = mciOpenParms.wDeviceID;

    // Begin recording and record for the specified number of 
    // milliseconds. Wait for recording to complete before continuing. 
    // Assume the default time format for the waveform-audio device 
    // (milliseconds).
    mciRecordParms.dwTo = dwMilliSeconds;
    if (dwReturn = mciSendCommand(wDeviceID, MCI_RECORD, 
        MCI_TO | MCI_WAIT, (DWORD)(LPVOID) &mciRecordParms))
    {
        mciSendCommand(wDeviceID, MCI_CLOSE, 0, NULL);
        return (dwReturn);
    }

    // Play the recording and query user to save the file.
    mciPlayParms.dwFrom = 0L;
    if (dwReturn = mciSendCommand(wDeviceID, MCI_PLAY,
        MCI_FROM | MCI_WAIT, (DWORD)(LPVOID) &mciPlayParms))
    {
        mciSendCommand(wDeviceID, MCI_CLOSE, 0, NULL);
        return (dwReturn);
    }
    if (MessageBox(hMainWnd, "Do you want to save this recording?",
        "", MB_YESNO) == IDNO)
    {
        mciSendCommand(wDeviceID, MCI_CLOSE, 0, NULL);
        return (0L);
    }

    // Save the recording to a file named TEMPFILE.WAV. Wait for
    // the operation to complete before continuing.
    mciSaveParms.lpfilename = "tempfile.wav";
    if (dwReturn = mciSendCommand(wDeviceID, MCI_SAVE,
        MCI_SAVE_FILE | MCI_WAIT, (DWORD)(LPVOID) &mciSaveParms))
    {
        mciSendCommand(wDeviceID, MCI_CLOSE, 0, NULL);
        return (dwReturn);
    }

    return (0L);
}