Lautstärke von PC ändern ?

[Matze]

Hallo,

für die Gesamtlautstärke geht es so:

Delphi-Quellcode:

uses
  MMSystem;

const
  MasterVolumeControl = 0;
  MaxVolume           = 65535;
  MinVolume           = 0;

function _VolumeControl(Mixer: hMixerObj;
             var Control: TMixerControl): MMResult;
var
  Line     : TMixerLine;
  Controls : TMixerLineControls;
begin
  ZeroMemory(@Line, SizeOf(Line));
  Line.cbStruct := SizeOf(Line);
  Line.dwComponentType := MIXERLINE_COMPONENTTYPE_DST_SPEAKERS;
  Result := mixerGetLineInfo(Mixer,
                             @Line,
                             MIXER_GETLINEINFOF_COMPONENTTYPE);
  if Result = MMSYSERR_NOERROR then begin
    ZeroMemory(@Controls, SizeOf(Controls));
    Controls.cbStruct := SizeOf(Controls);
    Controls.dwLineID := Line.dwLineID;
    Controls.cControls := 1;
    Controls.dwControlType := MIXERCONTROL_CONTROLTYPE_VOLUME;
    Controls.cbmxctrl := SizeOf(Control);
    Controls.pamxctrl := @Control;
    Result := mixerGetLineControls(Mixer,
                                   @Controls,
                                   MIXER_GETLINECONTROLSF_ONEBYTYPE);
  end;
end;

procedure SetMasterVolume(Mixer: hMixerObj; Value: Word);
var
  MasterVolume    : TMixerControl;
  Details         : TMixerControlDetails;
  UnsignedDetails : TMixerControlDetailsUnsigned;
  aCode            : MMResult;
begin
  aCode := _VolumeControl(Mixer, MasterVolume);
  if aCode = MMSYSERR_NOERROR then begin
    with Details do begin
      cbStruct := SizeOf(Details);
      dwControlID := MasterVolume.dwControlID;
      cChannels := 1;  // set all channels
      cMultipleItems := 0;
      cbDetails := SizeOf(UnsignedDetails);
      paDetails := @UnsignedDetails;
    end;
    UnsignedDetails.dwValue := Value;
    aCode := mixerSetControlDetails(Mixer,
                                   @Details,
                                   MIXER_SETCONTROLDETAILSF_VALUE);
  end;
  if aCode <> MMSYSERR_NOERROR then
    raise Exception.CreateFmt('SetMasterVolume failure, '+
                         'multimedia system error #%d', [aCode]);
end;

Ein möglicher Aufruf:

Delphi-Quellcode:

procedure TForm1.FormCreate(Sender: TObject);
begin
  TrackBar1.Min := MinVolume;
  TrackBar1.Max := MaxVolume;
end;

procedure TForm1.TrackBar1Change(Sender: TObject);
begin
  SetMasterVolume(MasterVolumeControl, TrackBar1.Position);
end;

Ich habe es getestet und es funktioniert. Den Code habe ich übrigens hier gefunden: Haupt Lautstärke Regeln

Grüße