精华区 [关闭][返回]

当前位置:网易精华区>>讨论区精华>>编程开发>>● Delphi>>多媒体及相关设备>>控制主音量,累了几天终于搞定了:)

主题:控制主音量,累了几天终于搞定了:)
发信人: delfan(你不疼我谁疼我)
整理人: teleme(2001-03-25 20:35:04), 站内信件
unit Volume;

interface

uses windows,mmsystem;

type 
    Tvolume=record
       left,right:word; // 取值范围 0--65535
    end;

procedure fillstruct(control:PMixerControl;var Cdetails:tMIXERCONTROLDETAILS);
function getpeak(control:PMixerControl;var peak:integer):boolean;
function setvolume(control:Pmixercontrol; volume:Tvolume):boolean;
function getvolume(control:Pmixercontrol; volume:Tvolume):boolean;

var
    mcontrols:array of array of array of PMixerControl; //mixer的数组,单声卡可以不用
    fmixerhandle:HMIXER;   //mixer的句柄

implementation

procedure fillstruct(control:PMixerControl;var Cdetails:tMIXERCONTROLDETAILS);
begin
    Cdetails.cbStruct:=sizeof(cdetails);
    cdetails.dwControlID:=Control.dwControlID;
    cdetails.cbDetails:=sizeof(integer);
    cdetails.hwndOwner:=0;
end;

function getpeak(control:PMixerControl;var peak:integer):boolean;
var
   details:TMixerControlDetailsSigned;
   cdetails:tMIXERCONTROLDETAILS;
begin
    Result:=false;
    if control.dwControlType<> mixercontrol_controltype_peakmeter then exit;
    cdetails.cChannels:=1;
    cdetails.paDetails:=@details;
    fillstruct(control,cdetails);
    result:=mixerGetControlDetails(fmixerhandle,@cdetails,MIXER_GETCONTROLDETAILSF_VALUE)=0;
end;

function setvolume(control:Pmixercontrol; volume:Tvolume):boolean;
var
    details:array[0..30] of integer;
    cdetails:tMIXERCONTROLDETAILS;
begin
    fillstruct(control,cdetails);
    cdetails.cChannels:=2;
    cdetails.paDetails:=@details;
    details[0]:=volume.left;
    details[1]:=volume.right;
    result:=mixerSetControlDetails(fmixerhandle,@cdetails,MIXER_GETCONTROLDETAILSF_VALUE)=0;
    volume.left:=details[0];
    volume.right:=details[1];
end;

function getvolume(control:Pmixercontrol; volume:Tvolume):boolean;
var
    details:array[0..30] of integer;
    cdetails:tMIXERCONTROLDETAILS;
begin
    fillstruct(control,cdetails);
    cdetails.cChannels:=2;
    cdetails.paDetails:=@details;
    result:=mixerGetControlDetails(fmixerhandle,@cdetails,MIXER_GETCONTROLDETAILSF_VALUE)=0;
    volume.left:=details[0];
    volume.right:=details[1];
end;

end.

// 调用方法:
procedure TForm1.Button1Click(Sender: TObject);
var  s : Tvolume;
     kz : Pmixercontrol;
begin
    new(kz); //<------------ 此处一定要分配内存
kz.dwControlID := 0;
s.left := 0;
s.right := 0;
try
setvolume(kz,s);
except
end;
freemem(kz);
end;



----
弹钢琴,弹琵琶,弹棉花.....弹什么都行,就是不许谈恋爱!

[关闭][返回]