Determining Nonstandard Format Support

To see whether a device supports a particular format (standard or nonstandard), you can call the waveOutOpen2MUO.P_ function with the WAVE_FORMAT_QUERY flag. The following example uses this technique to determine whether a waveform-audio device supports a specified format.

// Determines whether the specified waveform-audio output device

// supports a specified waveform-audio format. Returns

// MMSYSERR_NOERROR if the format is supported, WAVEERR_BADFORMAT if

// the format is not supported, and one of the other MMSYSERR_ error

// codes if there are other errors encountered in opening the

// specified waveform-audio device.

MMRESULT IsFormatSupported(LPWAVEFORMATEX pwfx, UINT uDeviceID)

{ 

    return (waveOutOpen(

        NULL,                 // ptr can be NULL for query

        uDeviceID,            // the device identifier

        pwfx,                 // defines requested format

        NULL,                 // no callback

        NULL,                 // no instance data

        WAVE_FORMAT_QUERY));  // query only, do not open device

}

This technique for determining nonstandard format support also applies to waveform-audio input devices. The only difference is that the waveInOpenDZFQLF function is used in place of waveOutOpen2MUO.P_ to query for format support.

To determine whether a particular waveform-audio data format is supported by any of the waveform-audio devices in a system, use the technique illustrated in the previous example, but specify the WAVE_MAPPER constant for the uDeviceID parameter.