windowsaudioinputdevice_mixer.cpp

Live media server used to transfer mpeg or other video/audio media

  : hMixer(NULL), dwRecLineID(0), numPorts(0), ports(NULL) {
}

Mixer::~Mixer() {
  delete[] ports;
}

void Mixer::open(unsigned numChannels, unsigned samplingFrequency, unsigned granularityInMS) {
  HMIXER newHMixer = NULL;
  do {
    MIXERCAPS mc;
    if (mixerGetDevCaps(index, &mc, sizeof mc) != MMSYSERR_NOERROR) break;
    
    // Copy the mixer name:
    strncpy(name, mc.szPname, MAXPNAMELEN);
    
    // Find the correct line for this mixer:
    unsigned i, uWavIn;
    unsigned nWavIn = waveInGetNumDevs();
    for (i = 0; i < nWavIn; ++i) {
      WAVEINCAPS wic;
      if (waveInGetDevCaps(i, &wic, sizeof wic) != MMSYSERR_NOERROR) continue;
      
      MIXERLINE ml;
      ml.cbStruct = sizeof ml;
      ml.Target.dwType  = MIXERLINE_TARGETTYPE_WAVEIN;
      strncpy(ml.Target.szPname, wic.szPname, MAXPNAMELEN);
      ml.Target.vDriverVersion = wic.vDriverVersion;
      ml.Target.wMid = wic.wMid;
      ml.Target.wPid = wic.wPid;
      
      if (mixerGetLineInfo((HMIXEROBJ)index, &ml, MIXER_GETLINEINFOF_TARGETTYPE/*|MIXER_OBJECTF_MIXER*/) == MMSYSERR_NOERROR) {
				// this is the right line
	uWavIn = i;
	dwRecLineID = ml.dwLineID;
	break;
      }
    }
    if (i >= nWavIn) break; // error: we couldn't find the right line
    
    if (mixerOpen(&newHMixer, index, (unsigned long)NULL, (unsigned long)NULL, MIXER_OBJECTF_MIXER) != MMSYSERR_NOERROR) break;
    if (newHMixer == NULL) break;
    
    // Sanity check: re-call "mixerGetDevCaps()" using the mixer device handle:
    if (mixerGetDevCaps((UINT)newHMixer, &mc, sizeof mc) != MMSYSERR_NOERROR) break;
    if (mc.cDestinations < 1) break; // error: this mixer has no destinations         
    
	if (!WindowsAudioInputDevice_common::openWavInPort(uWavIn, numChannels, samplingFrequency, granularityInMS)) break;

    hMixer = newHMixer;
    return;
  } while (0);
  
  // An error occurred:
  close(); 
}        

void Mixer::open() {
  open(1, 8000, 20);
}

void Mixer::getPortsInfo() {
  MIXERCAPS mc;
  mixerGetDevCaps((UINT)hMixer, &mc, sizeof mc);
  
  MIXERLINE mlt;
  unsigned i;
  for (i = 0; i < mc.cDestinations; ++i) {
    memset(&mlt, 0, sizeof mlt);
    mlt.cbStruct = sizeof mlt;
    mlt.dwDestination = i;
    if (mixerGetLineInfo((HMIXEROBJ)hMixer, &mlt, MIXER_GETLINEINFOF_DESTINATION) != MMSYSERR_NOERROR) continue;
    if (mlt.dwLineID == dwRecLineID) break; // this is the destination we're interested in
  }
  ports = new AudioInputPort[mlt.cConnections];
  
  numPorts = mlt.cConnections;
  for (i = 0; i < numPorts; ++i) {
    MIXERLINE mlc;
    memcpy(&mlc, &mlt, sizeof mlc);
    mlc.dwSource = i;
    mixerGetLineInfo((HMIXEROBJ)hMixer, &mlc, MIXER_GETLINEINFOF_SOURCE/*|MIXER_OBJECTF_HMIXER*/);
    ports[i].tag = mlc.dwLineID;
	ports[i].dwComponentType = mlc.dwComponentType;
    strncpy(ports[i].name, mlc.szName, MIXER_LONG_NAME_CHARS);
  }
  
  // Make the microphone the first port in the list:
  for (i = 1; i < numPorts; ++i) {
#ifdef OLD_MICROPHONE_TESTING_CODE
    if (_strnicmp("mic", ports[i].name, 3) == 0 ||
	_strnicmp("mik", ports[i].name, 3) == 0) {
#else
	if (ports[i].dwComponentType == MIXERLINE_COMPONENTTYPE_SRC_MICROPHONE) {
#endif
      AudioInputPort tmp = ports[0];
      ports[0] = ports[i];
      ports[i] = tmp;
    }
  }
}

Boolean Mixer::enableInputPort(unsigned portIndex, char const*& errReason, MMRESULT& errCode) {
  errReason = NULL; // unless there's an error
  AudioInputPort& port = ports[portIndex];
  
  MIXERCONTROL mc;
  mc.cMultipleItems = 1; // in case it doesn't get set below
  MIXERLINECONTROLS mlc;
#if 0 // the following doesn't seem to be needed, and can fail:
  mlc.cbStruct = sizeof mlc;
  mlc.pamxctrl = &mc;
  mlc.cbmxctrl = sizeof (MIXERCONTROL);
  mlc.dwLineID = port.tag;
  mlc.dwControlType = MIXERCONTROL_CONTROLTYPE_VOLUME;
  if ((errCode = mixerGetLineControls((HMIXEROBJ)hMixer, &mlc, MIXER_GETLINECONTROLSF_ONEBYTYPE/*|MIXER_OBJECTF_HMIXER*/)) != MMSYSERR_NOERROR) {
    errReason = "mixerGetLineControls()";
    return False;
  }
#endif
  
  MIXERLINE ml;
  memset(&ml, 0, sizeof (MIXERLINE));
  ml.cbStruct = sizeof (MIXERLINE);
  ml.dwLineID = port.tag;
  if ((errCode = mixerGetLineInfo((HMIXEROBJ)hMixer, &ml, MIXER_GETLINEINFOF_LINEID)) != MMSYSERR_NOERROR) {
    errReason = "mixerGetLineInfo()1";
    return False;
  }
  
  char portname[MIXER_LONG_NAME_CHARS+1];
  strncpy(portname, ml.szName, MIXER_LONG_NAME_CHARS);
  
  memset(&ml, 0, sizeof (MIXERLINE));
  ml.cbStruct = sizeof (MIXERLINE);
  ml.dwLineID = dwRecLineID;
  if ((errCode = mixerGetLineInfo((HMIXEROBJ)hMixer, &ml, MIXER_GETLINEINFOF_LINEID/*|MIXER_OBJECTF_HMIXER*/)) != MMSYSERR_NOERROR) {
    errReason = "mixerGetLineInfo()2";
    return False;
  }
  
  // Get Mixer/MUX control information (need control id to set and get control details)
  mlc.cbStruct = sizeof mlc;
  mlc.dwLineID = ml.dwLineID;
  mlc.cControls = 1;
  mc.cbStruct = sizeof mc; // Needed???#####
  mc.dwControlID = 0xDEADBEEF; // For testing #####
  mlc.pamxctrl = &mc;
  mlc.cbmxctrl = sizeof mc;
  mlc.dwControlType = MIXERCONTROL_CONTROLTYPE_MUX; // Single Select
  if ((errCode = mixerGetLineControls((HMIXEROBJ)hMixer, &mlc, MIXER_GETLINECONTROLSF_ONEBYTYPE/*|MIXER_OBJECTF_HMIXER*/)) != MMSYSERR_NOERROR) {
    mlc.dwControlType = MIXERCONTROL_CONTROLTYPE_MIXER; // Multiple Select
    mixerGetLineControls((HMIXEROBJ)hMixer, &mlc, MIXER_GETLINECONTROLSF_ONEBYTYPE/*|MIXER_OBJECTF_HMIXER*/);
  }
  
  unsigned matchLine = 0;
  if (mc.cMultipleItems > 1) {
    // Before getting control, we need to know which line to grab.
    // We figure this out by listing the lines, and comparing names:
    MIXERCONTROLDETAILS mcd;
    mcd.cbStruct = sizeof mcd;
    mcd.cChannels = ml.cChannels;
    mcd.cMultipleItems = mc.cMultipleItems;
    MIXERCONTROLDETAILS_LISTTEXT* mcdlText = new MIXERCONTROLDETAILS_LISTTEXT[mc.cMultipleItems];        
    mcd.cbDetails = sizeof (MIXERCONTROLDETAILS_LISTTEXT);
    mcd.paDetails = mcdlText;
    
    if (mc.dwControlID != 0xDEADBEEF) { // we know the control id for real
      mcd.dwControlID = mc.dwControlID;
      if ((errCode = mixerGetControlDetails((HMIXEROBJ)hMixer, &mcd, MIXER_GETCONTROLDETAILSF_LISTTEXT/*|MIXER_OBJECTF_HMIXER*/)) != MMSYSERR_NOERROR) {
	delete[] mcdlText;
	errReason = "mixerGetControlDetails()1";
	return False;
      }
    } else {
      // Hack: We couldn't find a MUX or MIXER control, so try to guess the control id:
      for (mc.dwControlID = 0; mc.dwControlID < 32; ++mc.dwControlID) {
	mcd.dwControlID = mc.dwControlID;
	if ((errCode = mixerGetControlDetails((HMIXEROBJ)hMixer, &mcd, MIXER_GETCONTROLDETAILSF_LISTTEXT/*|MIXER_OBJECTF_HMIXER*/)) == MMSYSERR_NOERROR) break;
      }
      if (mc.dwControlID == 32) { // unable to guess mux/mixer control id
	delete[] mcdlText;
	errReason = "mixerGetControlDetails()2";
	return False;
      }
    }
    
    for (unsigned i = 0; i < mcd.cMultipleItems; ++i) {
      if (strcmp(mcdlText[i].szName, portname) == 0) {
	matchLine = i;
	break;
      }
    }
    delete[] mcdlText;
  }
  
  // Now get control itself:
  MIXERCONTROLDETAILS mcd;
  mcd.cbStruct = sizeof mcd;
  mcd.dwControlID = mc.dwControlID;
  mcd.cChannels = ml.cChannels;
  mcd.cMultipleItems = mc.cMultipleItems;
  MIXERCONTROLDETAILS_BOOLEAN* mcdbState = new MIXERCONTROLDETAILS_BOOLEAN[mc.cMultipleItems];        
  mcd.paDetails = mcdbState;
  mcd.cbDetails = sizeof (MIXERCONTROLDETAILS_BOOLEAN);
  
  if ((errCode = mixerGetControlDetails((HMIXEROBJ)hMixer, &mcd, MIXER_GETCONTROLDETAILSF_VALUE/*|MIXER_OBJECTF_HMIXER*/)) != MMSYSERR_NOERROR) {
    delete[] mcdbState;
    errReason = "mixerGetControlDetails()3";
    return False;
  }
  
  for (unsigned j = 0; j < mcd.cMultipleItems; ++j) {
    mcdbState[j].fValue = (j == matchLine);
  }
  
  if ((errCode = mixerSetControlDetails((HMIXEROBJ)hMixer, &mcd, MIXER_OBJECTF_HMIXER)) != MMSYSERR_NOERROR) {
    delete[] mcdbState;
    errReason = "mixerSetControlDetails()";
    return False;
  }
  delete[] mcdbState;
  
  return True;
}


void Mixer::close() {
  WindowsAudioInputDevice_common::waveIn_close();
  if (hMixer != NULL) mixerClose(hMixer);
  hMixer = NULL; dwRecLineID = 0;
}