как отрегулировать громкость в vista/xp

Question

Я хочу отрегулировать громкость программно, как Get/SetMasterVolume в Vista и XP? используя блок mmsystem?

Answer 1

Вот реализация общего назначения API для аудио: MMDevApi

http://social.msdn.microsoft.com/Forums/en/windowspro-audiodevelopment/thread/5ce74d5d-2b1e-4ca9-a8c9-2e27eb9ec058

и пример с кнопкой

unit Unit33; 

interface 

uses 
    Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, 
    Dialogs, MMDevApi, ActiveX, StdCtrls; 

type 
    TForm33 = class(TForm) 
    Button1: TButton; 
    procedure FormCreate(Sender: TObject); 
    procedure Button1Click(Sender: TObject); 
    private 
    { Private declarations } 
    public 
    { Public declarations } 
    end; 

var 
    Form33: TForm33; 
    endpointVolume: IAudioEndpointVolume = nil; 

implementation 

{$R *.dfm} 


procedure TForm33.Button1Click(Sender: TObject); 
var 
    VolumeLevel: Single; 
begin 
    if endpointVolume = nil then Exit; 
    VolumeLevel := 0.50; 
    endpointVolume.SetMasterVolumeLevelScalar(VolumeLevel, nil); 
    Caption := Format('%1.8f', [VolumeLevel]) 
end; 

procedure TForm33.FormCreate(Sender: TObject); 
var 
    deviceEnumerator: IMMDeviceEnumerator; 
    defaultDevice: IMMDevice; 
begin 
    CoCreateInstance(CLASS_IMMDeviceEnumerator, nil, CLSCTX_INPROC_SERVER, IID_IMMDeviceEnumerator, deviceEnumerator); 
    deviceEnumerator.GetDefaultAudioEndpoint(eRender, eConsole, defaultDevice); 
    defaultDevice.Activate(IID_IAudioEndpointVolume, CLSCTX_INPROC_SERVER, nil, endpointVolume); 
end; 

end. 

Answer 2

Windows XP:

function SetMasterVolume(VolToSet: word; out VolSet: word): MMResult; 
var 
    MixerHandle: HMixer; 
    Volume: TMixerControlDetails_Unsigned; 
    MixerLine: TMixerLine; 
    MixerLineControls: TMixerLineControls; 
    VolumeCtrl: TMixerControl; 
    MixerControlDetails: TMixerControlDetails; 
begin 
    // Get mixer handle 
    Result := mixerOpen(@MixerHandle, 0, 0, 0, 0); 
    if Result <> MMSYSERR_NOERROR then Exit; 
    try 
    // Get master volume line 
    FillChar(MixerLine, SizeOf(TMixerLine), 0); 
    MixerLine.cbStruct := SizeOf(TMixerLine); 
    MixerLine.dwComponentType := MIXERLINE_COMPONENTTYPE_DST_SPEAKERS; 
    Result := mixerGetLineInfo(MixerHandle, @MixerLine, MIXER_GETLINEINFOF_COMPONENTTYPE); 

    if Result <> MMSYSERR_NOERROR then Exit; 
    // Get the volume control of the master volume line 
    FillChar(VolumeCtrl, SizeOf(TMixerControl), 0); 
    MixerLineControls.cbStruct := SizeOf(TMixerLineControls); 
    MixerLineControls.dwLineID := MixerLine.dwLineID; 
    MixerLineControls.dwControlType := MIXERCONTROL_CONTROLTYPE_VOLUME; 
    MixerLineControls.cControls := 1; 
    MixerLineControls.cbmxctrl := SizeOf(TMixerControl); 
    MixerLineControls.pamxctrl := @VolumeCtrl; 
    Result := mixerGetLineControls(MixerHandle,@MixerLineControls,MIXER_GETLINECONTROLSF_ONEBYTYPE); 

    if Result <> MMSYSERR_NOERROR then Exit; 
    // Set details (volume) for the volume control of the master volume line 
    FillChar(MixerControlDetails, SizeOf(TMixerControlDetails), 0); 
    MixerControlDetails.cbStruct := SizeOf(TMixerControlDetails); 
    MixerControlDetails.dwControlID := VolumeCtrl.dwControlID; 
    MixerControlDetails.cChannels := 1; 
    MixerControlDetails.cMultipleItems := 0; 
    MixerControlDetails.cbDetails := SizeOf(TMixerControlDetails_Unsigned); 
    MixerControlDetails.paDetails := @Volume; 
    Volume.dwValue := VolToSet; 
    Result := mixerSetControlDetails(MixerHandle, @MixerControlDetails,MIXER_SETCONTROLDETAILSF_VALUE); 
    finally 
    mixerClose(MixerHandle); 
    end; 
end; 

а также звонок:

var y:word; 
begin 
    SetMasterVolume(2000,y); 
end; 

Answer 3

MMDevApi имеет несколько неправильных объявлений. Двойные параметры должны быть одиночными. Булевы параметры лучше работают как целые. И многие, если не все параметры TGUID, должны быть PGUID. После исправления деклараций мне удалось установить уровень отключения звука и уровень громкости.

Answer 4

Окончательный код (для Delphi 7):

unit DevUnit; 


interface 

uses Windows, ActiveX, Classes, Graphics, OleServer, OleCtrls, StdVCL,ComObj; 


const 
    // TypeLibrary Major and minor versions 
    CLASS_IMMDeviceEnumerator: TGUID    = '{BCDE0395-E52F-467C-8E3D-C4579291692E}'; 
    IID_IMMDeviceEnumerator: TGUID    = '{A95664D2-9614-4F35-A746-DE8DB63617E6}'; 
    IID_IMMDevice: TGUID       = '{D666063F-1587-4E43-81F1-B948E807363F}'; 
    IID_IMMDeviceCollection: TGUID    = '{0BD7A1BE-7A1A-44DB-8397-CC5392387B5E}'; 
    IID_IAudioEndpointVolume: TGUID    = '{5CDF2C82-841E-4546-9722-0CF74078229A}'; 
    IID_IAudioMeterInformation : TGUID   = '{C02216F6-8C67-4B5B-9D00-D008E73E0064}'; 
    IID_IAudioEndpointVolumeCallback: TGUID  = '{657804FA-D6AD-4496-8A60-352752AF4F89}'; 
    DEVICE_STATE_ACTIVE     = $00000001; 
    DEVICE_STATE_UNPLUGGED    = $00000002; 
    DEVICE_STATE_NOTPRESENT    = $00000004; 
    DEVICE_STATEMASK_ALL     = $00000007; 

type 
    EDataFlow = TOleEnum; 
const 
    eRender        = $00000000; 
    eCapture        = $00000001; 
    eAll         = $00000002; 
    EDataFlow_enum_count     = $00000003; 

type 
    ERole = TOleEnum; 

const 
    eConsole        = $00000000; 
    eMultimedia       = $00000001; 
    eCommunications      = $00000002; 
    ERole_enum_count      = $00000003; 

type 

    IAudioEndpointVolumeCallback = interface(IUnknown) 
    ['{657804FA-D6AD-4496-8A60-352752AF4F89}'] 
    end; 

    IMMAudioEndpointVolume = interface(IUnknown) 
    ['{5CDF2C82-841E-4546-9722-0CF74078229A}'] 
    Function RegisterControlChangeNotify(AudioEndPtVol: IAudioEndpointVolumeCallback): Integer; stdcall; 
    Function UnregisterControlChangeNotify(AudioEndPtVol: IAudioEndpointVolumeCallback): Integer; stdcall; 
    Function GetChannelCount(out PInteger): Integer; stdcall; 
    Function SetMasterVolumeLevel(fLevelDB: single; pguidEventContext: PGUID):Integer; stdcall; 
    Function SetMasterVolumeLevelScalar(fLevelDB: single; pguidEventContext: PGUID):Integer; stdcall; 
    Function GetMasterVolumeLevel(out fLevelDB: single):Integer; stdcall; 
    Function GetMasterVolumeLevelScaler(out fLevel: single):Integer; stdcall; 
    Function SetChannelVolumeLevel(nChannel: Integer; fLevelDB: single; pguidEventContext: PGUID):Integer; stdcall; 
    Function SetChannelVolumeLevelScalar(nChannel: Integer; fLevelDB: single; pguidEventContext: PGUID):Integer; stdcall; 
    Function GetChannelVolumeLevel(nChannel: Integer; out fLevelDB: single) : Integer; stdcall; 
    Function GetChannelVolumeLevelScalar(nChannel: Integer; out fLevel: single) : Integer; stdcall; 
    Function SetMute(bMute: Boolean ; pguidEventContext: PGUID) :Integer; stdcall; 
    Function GetMute(out bMute: Boolean) :Integer; stdcall; 
    Function GetVolumeStepInfo(pnStep: Integer; out pnStepCount: Integer):Integer; stdcall; 
    Function VolumeStepUp(pguidEventContext: PGUID) :Integer; stdcall; 
    Function VolumeStepDown(pguidEventContext: PGUID) :Integer; stdcall; 
    Function QueryHardwareSupport(out pdwHardwareSupportMask): Integer; stdcall; 
    Function GetVolumeRange(out pflVolumeMindB: single; out pflVolumeMaxdB: single; out pflVolumeIncrementdB: single): Integer; stdcall; 
    end; 

    IPropertyStore = interface(IUnknown) 
    end; 

type 
    IMMDevice = interface(IUnknown) 
    ['{D666063F-1587-4E43-81F1-B948E807363F}'] 
    Function Activate( refId :PGUID; 
         dwClsCtx: DWORD; 
         pActivationParams: PInteger ; 
         out pEndpointVolume: IMMAudioEndpointVolume): Hresult; stdCall; 
    Function OpenPropertyStore(stgmAccess: DWORD; out ppProperties :IPropertyStore): Hresult; stdcall; 
    Function GetId(out ppstrId: PLPWSTR): Hresult; stdcall; 
    Function GetState(out State :Integer): Hresult; stdcall; 
    end; 

    IMMDeviceCollection = interface(IUnknown) 
    ['{0BD7A1BE-7A1A-44DB-8397-CC5392387B5E}'] 
    end; 
    IMMNotificationClient = interface (IUnknown) 
    ['{7991EEC9-7E89-4D85-8390-6C703CEC60C0}'] 
    end; 
    IMMDeviceEnumerator = interface(IUnknown) 
    ['{A95664D2-9614-4F35-A746-DE8DB63617E6}'] 
    Function EnumAudioEndpoints(dataFlow: EDataFlow; deviceState: SYSUINT; DevCollection:IMMDeviceCollection): Hresult ; stdcall; 
    Function GetDefaultAudioEndpoint(EDF: SYSUINT; ER: SYSUINT; out Dev :IMMDevice): Hresult ; stdcall; 
    Function GetDevice(pwstrId: pointer ; out Dev :IMMDevice) : HResult; stdcall; 
    Function RegisterEndpointNotificationCallback(pClient :IMMNotificationClient) :Hresult; stdcall; 
    end; 
    implementation 
end.