音量控制的问题 ( 积分: 100 )

据我所知，系统音量应是个独占性资源，但我发现 Windows Media Player 修改音量，并不影响系统的音量，或其它程序的音量，有哪位大虾知道它是如何实现的？

据我所知，系统音量应是个独占性资源，但我发现 Windows Media Player 修改音量，并不影响系统的音量，或其它程序的音量，有哪位大虾知道它是如何实现的？

我也很好奇，出名点的播放器都有这功能！如winamp,realplayer/千千静音...

可能 DX 类吧

winamp　好像没这个功能

理论上可以实现
如果你在输出音频数据之前，首先对输出音频数据进行调幅，那么完全可以实现如 Windows Media Player 的效果。

觉得　abookdog　讲的无道理：
为什么　winamp　和　Windows Media Player 同时播放， winamp 用的是系统音量，而　Windows Media Player 可以使用其自己设定的音量。

操作系统的音量是分很多种的！！
主音量控制，波形，SW同步，CD唱机，麦克风，。。。。。。。
给你一些猛料吧。
unit funVolume;

interface

uses MMSystem, Dialogs, windows;

Type TDeviceName = (dnMaster, Microphone, WaveOut, Synth);

function GetVolume(DN:TDeviceName) : DWord ;
procedure SetVolume(DN:TDeviceName;
Value:Word);
function GetVolumeMute(DN:TDeviceName) : Boolean;
procedure SetVolumeMute(DN:TDeviceName;
Value:Boolean);

implementation

//获取音量
function GetVolume(DN:TDeviceName) : DWord;
var
hMix: HMIXER;
mxlc: MIXERLINECONTROLS;
mxcd: TMIXERCONTROLDETAILS;
vol: TMIXERCONTROLDETAILS_UNSIGNED;
mxc: MIXERCONTROL;
mxl: TMixerLine;
intRet: Integer;
nMixerDevs: Integer;
begin

// Check if Mixer is available
nMixerDevs := mixerGetNumDevs();
if (nMixerDevs <
1) then

begin

Exit;
end;


// open the mixer
intRet := mixerOpen(@hMix, 0, 0, 0, 0);
if intRet = MMSYSERR_NOERROR then

begin

case DN of
dnMaster : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_DST_SPEAKERS;
Microphone :
mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_MICROPHONE;
WaveOut : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_WAVEOUT;
Synth : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_SYNTHESIZER;
end;

mxl.cbStruct := SizeOf(mxl);

// get line info
intRet := mixerGetLineInfo(hMix, @mxl, MIXER_GETLINEINFOF_COMPONENTTYPE);

if intRet = MMSYSERR_NOERROR then

begin

FillChar(mxlc, SizeOf(mxlc),0);
mxlc.cbStruct := SizeOf(mxlc);
mxlc.dwLineID := mxl.dwLineID;
mxlc.dwControlType := MIXERCONTROL_CONTROLTYPE_VOLUME;
mxlc.cControls := 1;
mxlc.cbmxctrl := SizeOf(mxc);

mxlc.pamxctrl := @mxc;
intRet := mixerGetLineControls(hMix, @mxlc, MIXER_GETLINECONTROLSF_ONEBYTYPE);

if intRet = MMSYSERR_NOERROR then

begin

FillChar(mxcd, SizeOf(mxcd),0);
mxcd.dwControlID := mxc.dwControlID;
mxcd.cbStruct := SizeOf(mxcd);
mxcd.cMultipleItems := 0;
mxcd.cbDetails := SizeOf(Vol);
mxcd.paDetails := @vol;
mxcd.cChannels := 1;

intRet := mixerGetControlDetails(hMix, @mxcd,MIXER_SETCONTROLDETAILSF_VALUE);

Result := vol.dwValue ;

if intRet <>
MMSYSERR_NOERROR then

ShowMessage('GetControlDetails Error');
end
else

ShowMessage('GetLineInfo Error');
end;

intRet := mixerClose(hMix);
end;

end;


//设置音量
procedure SetVolume(DN:TDeviceName;
Value : Word);
var
hMix: HMIXER;
mxlc: MIXERLINECONTROLS;
mxcd: TMIXERCONTROLDETAILS;
vol: TMIXERCONTROLDETAILS_UNSIGNED;
mxc: MIXERCONTROL;
mxl: TMixerLine;
intRet: Integer;
nMixerDevs: Integer;
begin

// Check if Mixer is available
nMixerDevs := mixerGetNumDevs();
if (nMixerDevs <
1) then

begin

Exit;
end;


// open the mixer
intRet := mixerOpen(@hMix, 0, 0, 0, 0);
if intRet = MMSYSERR_NOERROR then

begin

case DN of
dnMaster : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_DST_SPEAKERS;
Microphone :
mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_MICROPHONE;
WaveOut : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_WAVEOUT;
Synth : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_SYNTHESIZER;
end;

mxl.cbStruct := SizeOf(mxl);

// get line info
intRet := mixerGetLineInfo(hMix, @mxl, MIXER_GETLINEINFOF_COMPONENTTYPE);

if intRet = MMSYSERR_NOERROR then

begin

FillChar(mxlc, SizeOf(mxlc),0);
mxlc.cbStruct := SizeOf(mxlc);
mxlc.dwLineID := mxl.dwLineID;
mxlc.dwControlType := MIXERCONTROL_CONTROLTYPE_VOLUME;
mxlc.cControls := 1;
mxlc.cbmxctrl := SizeOf(mxc);

mxlc.pamxctrl := @mxc;
intRet := mixerGetLineControls(hMix, @mxlc, MIXER_GETLINECONTROLSF_ONEBYTYPE);

if intRet = MMSYSERR_NOERROR then

begin

FillChar(mxcd, SizeOf(mxcd),0);
mxcd.dwControlID := mxc.dwControlID;
mxcd.cbStruct := SizeOf(mxcd);
mxcd.cMultipleItems := 0;
mxcd.cbDetails := SizeOf(Vol);
mxcd.paDetails := @vol;
mxcd.cChannels := 1;

vol.dwValue := Value;

intRet := mixerSetControlDetails(hMix, @mxcd,MIXER_SETCONTROLDETAILSF_VALUE);

if intRet <>
MMSYSERR_NOERROR then

ShowMessage('SetControlDetails Error');
end
else

ShowMessage('GetLineInfo Error');
end;

intRet := mixerClose(hMix);
end;

end;


//获取静音
function GetVolumeMute(DN:TDeviceName) : Boolean;
var
hMix: HMIXER;
mxlc: MIXERLINECONTROLS;
mxcd: TMIXERCONTROLDETAILS;
vol: TMIXERCONTROLDETAILS_UNSIGNED;
mxc: MIXERCONTROL;
mxl: TMixerLine;
intRet: Integer;
nMixerDevs: Integer;
mcdMute: MIXERCONTROLDETAILS_BOOLEAN;
begin

// Check if Mixer is available
nMixerDevs := mixerGetNumDevs();
if (nMixerDevs <
1) then

begin

Exit;
end;


// open the mixer
intRet := mixerOpen(@hMix, 0, 0, 0, 0);
if intRet = MMSYSERR_NOERROR then

begin

case DN of
dnMaster : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_DST_SPEAKERS;
Microphone :
mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_MICROPHONE;
WaveOut : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_WAVEOUT;
Synth : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_SYNTHESIZER;
end;

mxl.cbStruct := SizeOf(mxl);

// mixerline info
intRet := mixerGetLineInfo(hMix, @mxl, MIXER_GETLINEINFOF_COMPONENTTYPE);

if intRet = MMSYSERR_NOERROR then

begin

FillChar(mxlc, SizeOf(mxlc),0);
mxlc.cbStruct := SizeOf(mxlc);
mxlc.dwLineID := mxl.dwLineID;
mxlc.dwControlType := MIXERCONTROL_CONTROLTYPE_MUTE;
mxlc.cControls := 1;
mxlc.cbmxctrl := SizeOf(mxc);
mxlc.pamxctrl := @mxc;

// Get the mute control
intRet := mixerGetLineControls(hMix, @mxlc, MIXER_GETLINECONTROLSF_ONEBYTYPE);

if intRet = MMSYSERR_NOERROR then

begin

FillChar(mxcd, SizeOf(mxcd),0);
mxcd.cbStruct := SizeOf(TMIXERCONTROLDETAILS);
mxcd.dwControlID := mxc.dwControlID;
mxcd.cChannels := 1;
mxcd.cbDetails := SizeOf(MIXERCONTROLDETAILS_BOOLEAN);
mxcd.paDetails := @mcdMute;

// Get mute
intRet := mixerGetControlDetails(hMix, @mxcd, MIXER_SETCONTROLDETAILSF_VALUE);

if mcdMute.fValue = 0 then
Result:=false
else
Result := True;

if intRet <>
MMSYSERR_NOERROR then

ShowMessage('SetControlDetails Error');
end
else

ShowMessage('GetLineInfo Error');
end;


intRet := mixerClose(hMix);
end;

end;


//设置静音
procedure SetVolumeMute(DN:TDeviceName;
Value:Boolean);
var
hMix: HMIXER;
mxlc: MIXERLINECONTROLS;
mxcd: TMIXERCONTROLDETAILS;
vol: TMIXERCONTROLDETAILS_UNSIGNED;
mxc: MIXERCONTROL;
mxl: TMixerLine;
intRet: Integer;
nMixerDevs: Integer;
mcdMute: MIXERCONTROLDETAILS_BOOLEAN;
begin

// Check if Mixer is available
nMixerDevs := mixerGetNumDevs();
if (nMixerDevs <
1) then

begin

Exit;
end;


// open the mixer
intRet := mixerOpen(@hMix, 0, 0, 0, 0);
if intRet = MMSYSERR_NOERROR then

begin

case DN of
dnMaster : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_DST_SPEAKERS;
Microphone :
mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_MICROPHONE;
WaveOut : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_WAVEOUT;
Synth : mxl.dwComponentType := MIXERLINE_COMPONENTTYPE_SRC_SYNTHESIZER;
end;

mxl.cbStruct := SizeOf(mxl);

// mixerline info
intRet := mixerGetLineInfo(hMix, @mxl, MIXER_GETLINEINFOF_COMPONENTTYPE);

if intRet = MMSYSERR_NOERROR then

begin

FillChar(mxlc, SizeOf(mxlc),0);
mxlc.cbStruct := SizeOf(mxlc);
mxlc.dwLineID := mxl.dwLineID;
mxlc.dwControlType := MIXERCONTROL_CONTROLTYPE_MUTE;
mxlc.cControls := 1;
mxlc.cbmxctrl := SizeOf(mxc);
mxlc.pamxctrl := @mxc;

// Get the mute control
intRet := mixerGetLineControls(hMix, @mxlc, MIXER_GETLINECONTROLSF_ONEBYTYPE);

if intRet = MMSYSERR_NOERROR then

begin

FillChar(mxcd, SizeOf(mxcd),0);
mxcd.cbStruct := SizeOf(TMIXERCONTROLDETAILS);
mxcd.dwControlID := mxc.dwControlID;
mxcd.cChannels := 1;
mxcd.cbDetails := SizeOf(MIXERCONTROLDETAILS_BOOLEAN);
mxcd.paDetails := @mcdMute;

// Set and UnSet mute
mcdMute.fValue := Ord(Value);
intRet := mixerSetControlDetails(hMix, @mxcd, MIXER_SETCONTROLDETAILSF_VALUE);

if intRet <>
MMSYSERR_NOERROR then

ShowMessage('SetControlDetails Error');
end
else

ShowMessage('GetLineInfo Error');
end;


intRet := mixerClose(hMix);
end;

end;


end.

{

http://www.csdn.net/develop/article/17/17257.shtm

标题 音量调节及静音 Haofei（原作）
关键字 音量调节，静音

在进行多媒体软件开发时，经常要调整各种设备的音量和设置静音，本
人编写了一个单元，四个函数，分别用于获取音量（GetVolume(DN))、
设置音量(SetVolume(DN,Value))、获取静音（GetVolumeMute(DN)）
及设置静音（SetVolumeMute(DN,Value)）。

}

如果你还不明白我就没办法了。

to 张辉明：
谢谢您的热情，我不是不知道如果获取、修改音量，而是如何不独占音量资源：
你可以试试看，用您的代码或别的软件，如 winamp、realplayer、超级解霸等，当修改音量时，打开的音量控制器是否变化，而在 Windows Media Player 中修改音量时，音量控制器又是否变化，就知道了，谢谢继续赐教！

控件本身提供啊
比如Dspack就提供了这么个属性。。。

这些规格全由微软定的啊,就像现在为什么asp.net跟php争地位,vc++跟delphi争地位一样了

解决了，谢谢　Genl