如何以编程方式更改主卷？
在Windows XP上的C / C ++中如何获取主卷或如何更改主卷…？
提前致谢…
MSDN库中API文档的起点就在这里 。
通过搜索MIXERCONTROL_CONTROLTYPE_VOLUME可以找到有用的代码，产生这样的代码（取自此处 ）
static const unsigned MAXIMUM_VOLUME_LEVEL_DEFINED_BY_USER = 100; Win32VolumeControl::Win32VolumeControl(const AudioDevice & audioDevice) { std::string deviceName = audioDevice.getData()[0]; //String deviceId = audioDevice.getData()[1]; EnumDeviceType::DeviceType deviceType = EnumDeviceType::toDeviceType(audioDevice.getData()[2]); _hMixer = NULL; int deviceId = Win32AudioDeviceId::getMixerDeviceId(deviceName); MMRESULT mr = initVolumeControl(deviceId, deviceType); if (mr != MMSYSERR_NOERROR) { _hMixer = NULL; _isSettable = false; if (deviceType == EnumDeviceType::DeviceTypeWaveIn) { deviceType = EnumDeviceType::DeviceTypeMicrophoneIn; MMRESULT mr = initVolumeControl(deviceId, deviceType); if (mr == MMSYSERR_NOERROR) { _isSettable = true; } } } else { _isSettable = true; } } Win32VolumeControl::~Win32VolumeControl() { close(); } int Win32VolumeControl::getLevel() { if (!_isSettable) { return 0; } MMRESULT mr = createMixerControl(MIXERCONTROL_CONTROLTYPE_VOLUME); if (mr != MMSYSERR_NOERROR) { return -1; } const unsigned MINIMUM_VOLUME_LEVEL = _mxc.Bounds.dwMinimum; const unsigned MAXIMUM_VOLUME_LEVEL = _mxc.Bounds.dwMaximum; MIXERCONTROLDETAILS_UNSIGNED mxcdVolume; MIXERCONTROLDETAILS mxcd; mxcd.cbStruct = sizeof(MIXERCONTROLDETAILS); mxcd.dwControlID = _mxc.dwControlID; mxcd.cChannels = 1; mxcd.cMultipleItems = 0; mxcd.cbDetails = sizeof(MIXERCONTROLDETAILS_UNSIGNED); mxcd.paDetails = &mxcdVolume; mr = ::mixerGetControlDetailsA((HMIXEROBJ) _hMixer, &mxcd, MIXER_OBJECTF_HMIXER | MIXER_GETCONTROLDETAILSF_VALUE); if (mr != MMSYSERR_NOERROR) { LOG_ERROR("couldn't get the volume level, mixerGetControlDetailsA() failed"); return -1; } return (int) (((float) ((mxcdVolume.dwValue - MINIMUM_VOLUME_LEVEL) * MAXIMUM_VOLUME_LEVEL_DEFINED_BY_USER) / (float) (MAXIMUM_VOLUME_LEVEL - MINIMUM_VOLUME_LEVEL)) + 0.5); } bool Win32VolumeControl::setLevel(unsigned level) { if (!_isSettable) { return false; } MMRESULT mr = createMixerControl(MIXERCONTROL_CONTROLTYPE_VOLUME); if (mr != MMSYSERR_NOERROR) { return false; } const unsigned MINIMUM_VOLUME_LEVEL = _mxc.Bounds.dwMinimum; const unsigned MAXIMUM_VOLUME_LEVEL = _mxc.Bounds.dwMaximum; MIXERCONTROLDETAILS_UNSIGNED mxcdVolume; mxcdVolume.dwValue = level * (MAXIMUM_VOLUME_LEVEL - MINIMUM_VOLUME_LEVEL) / MAXIMUM_VOLUME_LEVEL_DEFINED_BY_USER; MIXERCONTROLDETAILS mxcd; mxcd.cbStruct = sizeof(MIXERCONTROLDETAILS); mxcd.dwControlID = _mxc.dwControlID; mxcd.cChannels = 1; mxcd.cMultipleItems = 0; mxcd.cbDetails = sizeof(MIXERCONTROLDETAILS_UNSIGNED); mxcd.paDetails = &mxcdVolume; mr = ::mixerSetControlDetails((HMIXEROBJ) _hMixer, &mxcd, MIXER_OBJECTF_HMIXER | MIXER_SETCONTROLDETAILSF_VALUE); if (mr != MMSYSERR_NOERROR) { LOG_ERROR("couldn't set the volume level, mixerSetControlDetails() failed"); return false; } return true; } bool Win32VolumeControl::setMute(bool mute) { if (!_isSettable) { return false; } MMRESULT mr = createMixerControl(MIXERCONTROL_CONTROLTYPE_MUTE); if (mr != MMSYSERR_NOERROR) { return false; } MIXERCONTROLDETAILS_BOOLEAN mxcbMute; mxcbMute.fValue = mute; MIXERCONTROLDETAILS mxcd; mxcd.cbStruct = sizeof(MIXERCONTROLDETAILS); mxcd.dwControlID = _mxc.dwControlID; mxcd.cChannels = 1; mxcd.cMultipleItems = 0; mxcd.cbDetails = sizeof(MIXERCONTROLDETAILS_BOOLEAN); mxcd.paDetails = &mxcbMute; mr = ::mixerSetControlDetails((HMIXEROBJ) _hMixer, &mxcd, MIXER_OBJECTF_HMIXER | MIXER_SETCONTROLDETAILSF_VALUE); if (mr != MMSYSERR_NOERROR) { LOG_ERROR("couldn't mute/unmute the audio device, mixerSetControlDetails() failed"); return false; } return true; } bool Win32VolumeControl::isMuted() { if (!_isSettable) { return false; } MMRESULT mr = createMixerControl(MIXERCONTROL_CONTROLTYPE_MUTE); if (mr != MMSYSERR_NOERROR) { return false; } MIXERCONTROLDETAILS_BOOLEAN mxcbMute; MIXERCONTROLDETAILS mxcd; mxcd.cbStruct = sizeof(MIXERCONTROLDETAILS); mxcd.dwControlID = _mxc.dwControlID; mxcd.cChannels = 1; mxcd.cMultipleItems = 0; mxcd.cbDetails = sizeof(MIXERCONTROLDETAILS_BOOLEAN); mxcd.paDetails = &mxcbMute; mr = ::mixerGetControlDetailsA((HMIXEROBJ) _hMixer, &mxcd, MIXER_OBJECTF_HMIXER | MIXER_SETCONTROLDETAILSF_VALUE); if (mr != MMSYSERR_NOERROR) { LOG_ERROR("couldn't get if the audio device is mute/unmute, mixerGetControlDetailsA() failed"); return false; } return mxcbMute.fValue; } bool Win32VolumeControl::selectAsRecordDevice() { if (!_isSettable) { return false; } MMRESULT mr = createMixerControl(MIXERCONTROL_CONTROLTYPE_MUX); if (mr != MMSYSERR_NOERROR) { return false; } MIXERCONTROLDETAILS_BOOLEAN mxcbSelect; mxcbSelect.fValue = true; MIXERCONTROLDETAILS mxcd; mxcd.cbStruct = sizeof(MIXERCONTROLDETAILS); mxcd.dwControlID = _mxc.dwControlID; mxcd.cChannels = 1; mxcd.cMultipleItems = 0; mxcd.cbDetails = sizeof(MIXERCONTROLDETAILS_BOOLEAN); mxcd.paDetails = &mxcbSelect; mr = ::mixerSetControlDetails((HMIXEROBJ) _hMixer, &mxcd, MIXER_OBJECTF_HMIXER | MIXER_SETCONTROLDETAILSF_VALUE); if (mr != MMSYSERR_NOERROR) { LOG_ERROR("couldn't select the audio device as the record device, mixerSetControlDetails() failed"); return false; } return true; } bool Win32VolumeControl::isSelectedAsRecordDevice() { if (!_isSettable) { return false; } MMRESULT mr = createMixerControl(MIXERCONTROL_CONTROLTYPE_MUX); if (mr != MMSYSERR_NOERROR) { return false; } MIXERCONTROLDETAILS_BOOLEAN mxcbSelect; MIXERCONTROLDETAILS mxcd; mxcd.cbStruct = sizeof(MIXERCONTROLDETAILS); mxcd.dwControlID = _mxc.dwControlID; mxcd.cChannels = 1; mxcd.cMultipleItems = 0; mxcd.cbDetails = sizeof(MIXERCONTROLDETAILS_BOOLEAN); mxcd.paDetails = &mxcbSelect; mr = ::mixerGetControlDetailsA((HMIXEROBJ) _hMixer, &mxcd, MIXER_OBJECTF_HMIXER | MIXER_SETCONTROLDETAILSF_VALUE); if (mr != MMSYSERR_NOERROR) { LOG_ERROR("couldn't select the audio device as the record device, mixerSetControlDetails() failed"); return false; } return mxcbSelect.fValue; } bool Win32VolumeControl::close() { if (!_isSettable) { return false; } if (_hMixer) { MMRESULT mr = ::mixerClose(_hMixer); if (mr != MMSYSERR_NOERROR) { LOG_ERROR("couldn't close the mixer, mixerClose() failed"); return false; } return true; } return false; } Win32VolumeControl::initVolumeControl(unsigned deviceId, EnumDeviceType::DeviceType deviceType) { MMRESULT mr = ::mixerOpen(&_hMixer, deviceId, NULL, NULL, MIXER_OBJECTF_MIXER); if (mr != MMSYSERR_NOERROR) { _hMixer = NULL; return mr; } MIXERCAPSA mxcaps; mr = ::mixerGetDevCapsA(deviceId, &mxcaps, sizeof(MIXERCAPSA)); if (mr != MMSYSERR_NOERROR) { return mr; } LOG_DEBUG("manufacturer's name for the mixer=" + std::string(mxcaps.szPname) + " " + String::fromNumber(mxcaps.wMid) + " " + String::fromNumber(mxcaps.wPid)); DWORD dwComponentType; switch (deviceType) { case EnumDeviceType::DeviceTypeWaveOut: dwComponentType = MIXERLINE_COMPONENTTYPE_SRC_WAVEOUT; break; case EnumDeviceType::DeviceTypeWaveIn: dwComponentType = MIXERLINE_COMPONENTTYPE_DST_WAVEIN; break; case EnumDeviceType::DeviceTypeCDOut: dwComponentType = MIXERLINE_COMPONENTTYPE_SRC_COMPACTDISC; break; case EnumDeviceType::DeviceTypeMicrophoneOut: dwComponentType = MIXERLINE_COMPONENTTYPE_SRC_MICROPHONE; break; case EnumDeviceType::DeviceTypeMicrophoneIn: dwComponentType = MIXERLINE_COMPONENTTYPE_DST_WAVEIN; break; case EnumDeviceType::DeviceTypeMasterVolume: dwComponentType = MIXERLINE_COMPONENTTYPE_DST_SPEAKERS; break; default: LOG_FATAL("unknow device type=" + EnumDeviceType::toString(deviceType)); } mr = createMixerLine(dwComponentType); if (mr != MMSYSERR_NOERROR) { return mr; } //For microphone in, we first look for the wave in mixer //and then for the microphone if (deviceType == EnumDeviceType::DeviceTypeMicrophoneIn) { mr = createSecondMixerLine(MIXERLINE_COMPONENTTYPE_SRC_MICROPHONE); if (mr != MMSYSERR_NOERROR) { return mr; } } // mr = createMixerControl(MIXERCONTROL_CONTROLTYPE_VOLUME); if (mr != MMSYSERR_NOERROR) { return mr; } LOG_DEBUG("destination line name=" + std::string(_mxl.szName) + " volume controller name=" + std::string(_mxc.szName)); //Everything went fine return mr; } MMRESULT Win32VolumeControl::createMixerLine(DWORD dwComponentType) { _mxl.cbStruct = sizeof(MIXERLINEA); _mxl.dwComponentType = dwComponentType; MMRESULT mr = ::mixerGetLineInfoA((HMIXEROBJ) _hMixer, &_mxl, MIXER_OBJECTF_HMIXER | MIXER_GETLINEINFOF_COMPONENTTYPE); if (mr != MMSYSERR_NOERROR) { LOG_ERROR("mixerGetLineInfoA() failed using dwComponentType=" + String::fromNumber(dwComponentType)); } return mr; } MMRESULT Win32VolumeControl::createSecondMixerLine(DWORD dwComponentType) { unsigned connections = _mxl.cConnections; DWORD destination = _mxl.dwDestination; MMRESULT mr; for (unsigned i = 0; i < connections; ++i) { _mxl.cbStruct = sizeof(MIXERLINEA); _mxl.dwSource = i; _mxl.dwDestination = destination; mr = ::mixerGetLineInfoA((HMIXEROBJ) _hMixer, &_mxl, MIXER_OBJECTF_HMIXER | MIXER_GETLINEINFOF_SOURCE); if (mr == MMSYSERR_NOERROR && _mxl.dwComponentType == dwComponentType) { break; } } if (mr != MMSYSERR_NOERROR) { LOG_ERROR("mixerGetLineInfoA() failed using dwComponentType=" + String::fromNumber(dwComponentType)); } return mr; } MMRESULT Win32VolumeControl::createMixerControl(DWORD dwControlType) { _mxlc.cbStruct = sizeof(MIXERLINECONTROLSA); _mxlc.dwLineID = _mxl.dwLineID; //MIXERCONTROL_CONTROLTYPE_VOLUME //MIXERCONTROL_CONTROLTYPE_MIXER //MIXERCONTROL_CONTROLTYPE_MUX //MIXERCONTROL_CONTROLTYPE_MUTE _mxlc.dwControlType = dwControlType; _mxlc.cControls = 1; _mxlc.cbmxctrl = sizeof(MIXERCONTROLA); _mxlc.pamxctrl = &_mxc; MMRESULT mr = ::mixerGetLineControlsA((HMIXEROBJ) _hMixer, &_mxlc, MIXER_OBJECTF_HMIXER | MIXER_GETLINECONTROLSF_ONEBYTYPE); if (mr != MMSYSERR_NOERROR) { LOG_ERROR("mixerGetLineControlsA() failed using dwControType=" + String::fromNumber(dwControlType)); } return mr; }
这里。
#include #pragma comment(lib, "winmm") // to mute: waveOutSetVolume(NULL, 0); // full volume: waveOutSetVolume(NULL, 0xFFFF);
传统混音器API可能难以使用。 我建议使用WASAPI API。
WASAPI – http://msdn.microsoft.com/en-us/library/dd371455(v=VS.85).aspx