只有使用 IDirectSoundBuffer8 的次缓冲区才能设置"特效", 主缓冲区主要负责的是混音和处理 3D 效果.
IDirectSoundBuffer8(非 IDirectSoundBuffer) 支持以下效果器:
IDirectSoundFXChorus8 //合唱; 微调原生与回声的延迟 IDirectSoundFXCompressor8 //压缩; 压缩某些振幅 IDirectSoundFXDistortion8 //失真; 将波形顶部修改为方形或锯齿形 IDirectSoundFXEcho8 //回声; 重复并衰减回声 IDirectSoundFXFlanger8 //镶边; 延迟回声 IDirectSoundFXGargle8 //漱口; 有人叫它咕嘟效果 IDirectSoundFXI3DL2Reverb8 //环境混响; 房间、大厅等 IDirectSoundFXParamEq8 //均衡; 缩放不同频率的信号 IDirectSoundFXWavesReverb8 //混响; DirectX Media Objects(DMOs), 是微软从 Waves 购买的声音处理技术
使用步骤:
1、通过 IDirectSoundBuffer8 的 SetFX() 方法关联特效, 这个过程主要是给 SetFX() 方法的参数准备 TDSEffectDesc 结构数组;
2、通过 IDirectSoundBuffer8 的 GetObjectInPath() 方法获取特效对象;
3、通过特效对象的 SetAllParameters() 方法设置特效参数.
9 个特效对象都只有两个方法: GetAllParameters()、SetAllParameters(), 两方法的参数都是结构体(各不相同).
{给 IDirectSoundBuffer8 关联特效; 不能在缓冲区锁定或播放时使用:}
function SetFX(
dwEffectsCount: DWORD; //特效数目, 即第二个参数 pDSFXDesc 的大小
pDSFXDesc: PDSEffectDesc; //TDSEffectDesc 结构的数组
pdwResultCodes: PDWORD //接收设置结果, 不需要则给 nil
): HResult; stdcall;
//可以使用 SefFX(0, nil, nil) 删除缓冲区的所有特效.
{SetFX() 方法用到的结构体:}
TDSEffectDesc = packed record
dwSize : DWORD; //结构大小
dwFlags : DWORD; //处理标志; 一般给 0
guidDSFXClass : TGUID; //指定要使用的效果
dwReserved1 : DWORD_PTR; //未使用
dwReserved2 : DWORD_PTR; //未使用
end;
//DSEffectDesc.dwFlags
DSFX_LOCHARDWARE = $00000001; //使用硬件处理效果; 这其实在 Direct9.0 还不支持
DSFX_LOCSOFTWARE = $00000002; //使用软件处理效果; 同默认
0 //默认
//DSEffectDesc.guidDSFXClass, 这分别是上面九个接口对应的 GUID 查询标识:
GUID_DSFX_STANDARD_CHORUS
GUID_DSFX_STANDARD_COMPRESSOR
GUID_DSFX_STANDARD_DISTORTION
GUID_DSFX_STANDARD_ECHO
GUID_DSFX_STANDARD_FLANGER
GUID_DSFX_STANDARD_GARGLE
GUID_DSFX_STANDARD_I3DL2REVERB
GUID_DSFX_STANDARD_PARAMEQ
GUID_DSFX_WAVES_REVERB
{从 IDirectSoundBuffer8 获取特效对象的方法}
function GetObjectInPath(
const rguidObject: TGUID; //对象查询标识, GUID_DSFX_ ...
dwIndex: DWORD; //该特效在 SetFX() 安排特效数组时的索引
const rguidInterface: TGUID; //对象的唯一标识, IID_IDirectSoundFX ... 或 IDirectSoundFX ...
out ppObject //返回要获取的特效接口
): HResult; stdcall;
{IDirectSoundFXGargle8.SetAllParameters() 需要结构体}
TDSFXGargle = packed record
dwRateHz: DWORD; //频率; 取值范围 1..1000, 默认 20
dwWaveShape: DWORD; //波形; 三角波(0)、方波(1)
end;
//TDSFXGargle.dwRateHz 取值范围, 默认是 20
DSFXGARGLE_RATEHZ_MIN = 1; //
DSFXGARGLE_RATEHZ_MAX = 1000; //
DSFXGARGLE_WAVE_TRIANGLE = 0; //三角波
DSFXGARGLE_WAVE_SQUARE = 1; //方波
为让代码更简洁, 又把前面自定义的 ReadWave 该为了 ReadWave2 (增加了一个 OpenDialog 方法):
unit ReadWave2;
interface
uses Windows, Classes, SysUtils, MMSystem, Dialogs;
type
TReadWave = class
private
FFileHandle: HMMIO;
FFormat: TWaveFormatEx;
FSize: DWORD;
function GetFormatAndSize(hFile: HMMIO): Boolean;
public
destructor Destroy; override;
function Open(FileName: string): Boolean; //从文件打开
function OpenResource(ResName: string): Boolean; //从资源打开, 资源的指定格式必须是 WAVE
function OpenDialog: Boolean; //从对话框打开
function Read(pDest: Pointer; Size: DWORD): Boolean; //读出波形数据
property Format: TWaveFormatEx read FFormat; //读出格式数据
property Size: DWORD read FSize; //读出波形数据的大小
end;
implementation
{ TReadWave }
destructor TReadWave.Destroy;
begin
if FFileHandle > 0 then mmioClose(FFileHandle, 0);
inherited;
end;
function TReadWave.GetFormatAndSize(hFile: HMMIO): Boolean;
var
ckiRIFF,ckiFmt,ckiData: TMMCKInfo;
begin
Result := False;
if hFile = 0 then Exit;
ZeroMemory(@ckiRIFF, SizeOf(TMMCKInfo));
mmioDescend(hFile, @ckiRIFF, nil, MMIO_FINDRIFF);
if (ckiRIFF.ckid <> FOURCC_RIFF) or (ckiRIFF.fccType <> mmioStringToFOURCC('WAVE',0)) then Exit;
ZeroMemory(@FFormat, SizeOf(TWaveFormatEx));
ZeroMemory(@ckiFmt, SizeOf(TMMCKInfo));
ckiFmt.ckid := mmioStringToFOURCC('fmt', 0);
ZeroMemory(@ckiData, SizeOf(TMMCKInfo));
ckiData.ckid := mmioStringToFOURCC('data', 0);
if (mmioDescend(hFile, @ckiFmt, @ckiRIFF, MMIO_FINDCHUNK) = MMSYSERR_NOERROR) then mmioRead(hFile, @FFormat, SizeOf(TWaveFormatEx));
mmioAscend(hFile, @ckiFmt, 0);
if (mmioDescend(hFile, @ckiData, @ckiRIFF, MMIO_FINDCHUNK) = MMSYSERR_NOERROR) then FSize := ckiData.cksize;
Result := FFormat.wFormatTag = WAVE_FORMAT_PCM;
end;
function TReadWave.Open(FileName: string): Boolean;
begin
Result := False;
if not FileExists(FileName) then Exit;
if FFileHandle > 0 then mmioClose(FFileHandle, 0);
FFileHandle := mmioOpen(PChar(FileName), nil, MMIO_READ);
Result := GetFormatAndSize(FFileHandle);
end;
function TReadWave.OpenDialog: Boolean;
begin
with TOpenDialog.Create(nil) do begin
Filter := 'Wave File(*.wav)|*.wav';
if Execute then Result := Open(FileName);
Free;
end;
end;
function TReadWave.OpenResource(ResName: string): Boolean;
var
res: TResourceStream;
mmioInfo: TMMIOInfo;
begin
Result := False;
res := TResourceStream.Create(HInstance, ResName, 'WAVE');
ZeroMemory(@mmioInfo, SizeOf(TMMIOInfo));
mmioInfo.fccIOProc := FOURCC_MEM;
mmioInfo.cchBuffer := res.Size;
mmioInfo.pchBuffer := res.Memory;
if FFileHandle > 0 then mmioClose(FFileHandle, 0);
FFileHandle := mmioOpen(nil, @mmioInfo, MMIO_ALLOCBUF or MMIO_READ);
Result := GetFormatAndSize(FFileHandle);
res.Free;
end;
function TReadWave.Read(pDest: Pointer; Size: DWORD): Boolean;
begin
Result := mmioRead(FFileHandle, pDest, Size) = Size;
end;
end.
测试代码:
unit Unit1;
interface
uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, StdCtrls, ExtCtrls, ComCtrls;
type
TForm1 = class(TForm)
Button1: TButton; //打开并播放
Button2: TButton; //停止
TrackBar1: TTrackBar; //用于调整 TDSFXGargle.dwRateHz
RadioGroup1: TRadioGroup; //用于调整 TDSFXGargle.dwWaveShape
procedure FormCreate(Sender: TObject);
procedure FormDestroy(Sender: TObject);
procedure Button1Click(Sender: TObject);
procedure Button2Click(Sender: TObject);
procedure TrackBar1Change(Sender: TObject); //RadioGroup1.OnClick 也关联它
end;
var
Form1: TForm1;
implementation
{$R *.dfm}
uses DirectSound, ReadWave2; //ReadWave2 是刚刚修改过的自定义单元
var
myDSound: IDirectSound8;
buf8: IDirectSoundBuffer8;
fxGargle: IDirectSoundFXGargle8; //IDirectSoundFXGargle8 效果器
{建立设备对象并初始化界面}
procedure TForm1.FormCreate(Sender: TObject);
begin
DirectSoundCreate8(nil, myDSound, nil);
myDSound.SetCooperativeLevel(Handle, DSSCL_NORMAL);
TrackBar1.Min := DSFXGARGLE_RATEHZ_MIN; //1
TrackBar1.Max := DSFXGARGLE_RATEHZ_MAX; //1000
TrackBar1.Position := 20; //默认值
TrackBar1.ShowSelRange := False;
TrackBar1.TickStyle := tsNone;
RadioGroup1.Items.CommaText := 'TRIANGLE, SQUARE';
RadioGroup1.Columns := 2;
RadioGroup1.ItemIndex := 0;
RadioGroup1.OnClick := TrackBar1.OnChange; //两个事件的代码相同
System.ReportMemoryLeaksOnShutdown := true;
end;
{建立缓冲区、关联特效、获取特效对象并播放}
procedure TForm1.Button1Click(Sender: TObject);
var
buf: IDirectSoundBuffer; //最终需要的是 IDirectSoundBuffer8, 这里的 IDirectSoundBuffer 只是做个桥
bufDesc: TDSBufferDesc;
rEffect: TDSEffectDesc; //SetFX() 方法需要的结构
wav: TReadWave;
p1: Pointer;
n1: DWORD;
begin
{经过对自定义单元的修改, 现在调入一个 Wave 很方便}
wav := TReadWave.Create;
if not wav.OpenDialog then begin wav.Free; Exit; end;
{获取 IDirectSoundBuffer8 接口对象}
ZeroMemory(@bufDesc, SizeOf(TDSBufferDesc));
bufDesc.dwSize := SizeOf(TDSBufferDesc);
bufDesc.dwFlags := DSBCAPS_CTRLFX; //!
bufDesc.dwBufferBytes := wav.Size;
bufDesc.lpwfxFormat := @wav.Format;
myDSound.CreateSoundBuffer(bufDesc, buf, nil);
buf.QueryInterface(IID_IDirectSoundBuffer8, buf8);
{载入波形}
buf8.Lock(0, 0, @p1, @n1, nil, nil, DSBLOCK_ENTIREBUFFER);
wav.Read(p1, n1);
wav.Free;
buf8.Unlock(p1, n1, nil, 0);
{准备 SetFX() 需要的结构}
ZeroMemory(@rEffect, SizeOf(TDSEffectDesc));
rEffect.dwSize := SizeOf(TDSEffectDesc);
rEffect.dwFlags := 0;
rEffect.guidDSFXClass := GUID_DSFX_STANDARD_GARGLE; //指定是 IDirectSoundFXGargle8 效果器
{关联效果器}
buf8.SetFX(1, @rEffect, nil); //参数应该是个数组, 既然只有一个元素, 就先省了
{获取效果器对象}
buf8.GetObjectInPath(GUID_DSFX_STANDARD_GARGLE, 0, IID_IDirectSoundFXGargle8, fxGargle);
{播放}
buf8.Play(0, 0, DSBPLAY_LOOPING);
// buf := nil; //局部接口会被自动释放
end;
{停止播放}
procedure TForm1.Button2Click(Sender: TObject);
begin
if Assigned(buf8) then buf8.Stop;
end;
{特效变换}
procedure TForm1.TrackBar1Change(Sender: TObject);
var
rGargle: TDSFXGargle;
begin
if buf8 = nil then Exit;
rGargle.dwRateHz := TrackBar1.Position;
rGargle.dwWaveShape := RadioGroup1.ItemIndex;
fxGargle.SetAllParameters(rGargle);
end;
procedure TForm1.FormDestroy(Sender: TObject);
begin
buf8 := nil;
myDSound := nil;
end;
end.
运行效果图:
