Delphi中捕获音频函数OnWaveIn的使用小记
说明，并非给别人看，只是为了防止自己忘记，所以没有写说明与注释之类的，不好意思了。
上次有个朋友叫我帮忙写一个小程序，用处比较怪。显示图片，并开始计时，当测试者说出图像内容的时候（无需识别具体的语音内容），停止计时。这样循环显示一系列图片，并记录从显示图片，到发出声音的这段时间。据说是研究语言学使用的。于是用Delphi写了一个小程序，其中记录声音，过滤噪音，判断是否发出声音的程序如下：
具体调用：
上次有个朋友叫我帮忙写一个小程序，用处比较怪。显示图片，并开始计时，当测试者说出图像内容的时候（无需识别具体的语音内容），停止计时。这样循环显示一系列图片，并记录从显示图片，到发出声音的这段时间。据说是研究语言学使用的。于是用Delphi写了一个小程序，其中记录声音，过滤噪音，判断是否发出声音的程序如下：
unit SoundCap_Unit;
interface
uses
Windows, Messages, MMSystem, Classes, SysUtils, Math, Forms, Controls;
Const
BufferTime : Real = 120; // 每次0.120秒 0.120 * 1000
type
TData8 = array [0..127] of byte;
PData8 = ^TData8;
TData16 = array [0..127] of smallint;
PData16 = ^TData16;
TPointArr = array [0..127] of TPoint;
PPointArr = ^TPointArr;
TShowProgressEvent = procedure (Sender: TObject; Position: Integer) of object;
TCaptureEvent = procedure (Sender: TObject; passTime : Integer) of Object;
TShowTimeEvent = procedure (Sender : TObject; Time : Integer) of Object;
TSoundCap = Class(TCustomControl)
private
FOnShowTime : TShowTimeEvent;
FOnShowProgress : TShowProgressEvent;
FOnCapture : TCaptureEvent;
function GetMidValue(i : Integer) : Integer; //计算中值
protected
procedure DoShowTime;//(Time : Integer); dynamic;
procedure DoShowProgress(position : Integer); dynamic;
procedure DoCapture(passTime : DWORD ); dynamic;
public
FilterValve : Integer; //音频过滤的阀值
isCapture : boolean ;
//constructor Create(AOwner: TComponent); overload;
constructor Create(handle : THandle); //overload;
destructor Destroy; override;
procedure OpenCapture(handle : THandle);
procedure CloseCapture;
procedure OnWaveIn(var Msg: TMessage); message MM_WIM_DATA;
procedure StartCap;
procedure StopCap;
property OnShowTime: TShowTimeEvent read FOnShowTime write FOnShowTime;
property OnShowProgress: TShowProgressEvent read FOnShowProgress write FOnShowProgress;
property OnCapture: TCaptureEvent read FOnCapture write FOnCapture;
end;
implementation
{ TSoundCap }
var
WaveIn: hWaveIn;
hBuf: THandle;
BufHead: TWaveHdr;
bufsize: integer;
Bits16: boolean;
p: PPointArr;
p2 : PPointArr;
stop: boolean = false;
StartTime : DWORD ;
Count : integer = 0;
constructor TSoundCap.Create(Handle : THandle);//(AOwner: TComponent);
begin
// ParentWindow := AOwner;
Inherited Create(nil);
ParentWindow := handle;
isCapture := false;
FilterValve := 3;
end;
destructor TSoundCap.Destroy;
begin
inherited;
CloseCapture;
end;
//触发捕获音频事件
procedure TSoundCap.DoCapture(passTime : DWORD );
var
EndTime : DWORD ;
begin
EndTime := GetTickCount;
if Assigned(FOnCapture) then FOnCapture(Self, EndTime - StartTime - passTime);
end;
//显示音频强度
procedure TSoundCap.DoShowProgress(position: Integer);
begin
if Assigned(FOnShowProgress) then FOnShowProgress(Self, position);
end;
//显示时间
procedure TSoundCap.DoShowTime;//(Time : Integer);
var
EndTime : DWORD ;
begin
EndTime := GetTickCount;
if Assigned(FOnShowTime) then FOnShowTime(Self, EndTime - StartTime);
end;
//中值过滤
function TSoundCap.GetMidValue(i: Integer): Integer;
var
v0,v1,v2 : integer;
h : integer;
mid : integer;
begin
h := 100;
v0 := p^[i-2].Y;
v1 := p^[i-1].Y;
v2 := p^[i].Y;
mid := (v0 + v1 + v2) div 3;
if abs(abs(mid) - v1) > FilterValve then
Result := mid
Else if abs(mid - h/2) < FilterValve then
Result := 0
Else
Result := v1;
end;
//处理Wave数据采集
procedure TSoundCap.OnWaveIn(var Msg: TMessage);
var
data8 : PData8;
i, x, y : integer;
StartPos, EndPos, SCount : integer;
passTime , MaxValue , tmp : Integer;
dtime : DWORD;
begin
//DoCapture(0);
MaxValue := 0;
Data8 := PData8(PWaveHdr(Msg.lParam)^.lpData);
//将Buffer中采集的数据存入 P 中
for i := 0 to BufSize - 1 do
Begin
x := i;
y := Round(abs(data8^[i] - 128) * 100 / 128); //data8^[i] 为 128 - 256 之间
p^[i] := Point(x, y);
//计算滤波后的值 , 滤波之后的数据存入 P2 中
if (i > 1) and (i < BufSize ) then
Begin
p2^[i] := Point(p^[i].X, GetMidValue(i));
end;
//p2^[i] := GetMidValue(x,y,i);
//Inc(count,data8^[i]);
//count := count + Round(abs(data8^[i] - 128) * 100 / 128);
//ShowProgress(Round(count / BufSize));
tmp := Round(abs(data8^[i] - 128) * 100 / 128);
if tmp > MaxValue Then
MaxValue := tmp;
//count := count + tmp;
End;
p2^[0] := Point(p^[0].X, GetMidValue(2));
p2^[1] := Point(p^[0].X, GetMidValue(2));
//Caption := IntToStr(count div BufSize);
//不需要绘画音频曲线
{
with PaintBox1.Canvas do begin
Brush.Color := clBlack;
Pen.Color := clGreen;
FillRect(ClipRect);
Polyline(Slice(p^, BufSize));
end;
with PaintBox2.Canvas do begin
Brush.Color := clBlack;
Pen.Color := clGreen;
FillRect(ClipRect);
Polyline(Slice(p2^, BufSize));
end;
}
//判断是否有超出域值的数据
StartPos := 0;
EndPos := 0;
SCount := 0;
for I := 0 to BufSize - 1 do
begin
if abs(p2^[i].Y ) > FilterValve then
Begin
if StartPos = 0 then
StartPos := i;
Inc(SCount);
end Else if StartPos = 0 then
p^[i].Y := 0;//h div 2;
if (SCount > 20) then
if (EndPos = 0) then
EndPos := Min((StartPos + BufSize div 2 ) , BufSize - 1)
Else if EndPos < i then
p^[i].Y := 0;//h div 2;
end;
{
if (SCount > 20) and isCapture then
with PaintBox3.Canvas do begin
Brush.Color := clBlack;
Pen.Color := clGreen;
FillRect(ClipRect);
Polyline(Slice(p^, BufSize));
isCapture := false;
Timer1.Enabled := true;
passTime := Round(StartPos * BufferTime / BufSize);
RecordTime(passTime);
end; }
//Show Time
If isCapture Then DoShowTime();
//SCount := 100;
//StartPos := 0;
//如果有音频超出阀值，并且正在捕捉，则记录具体时间
dtime := GetTickCount - StartTime;
//如果说 dtime < 120 , 则这个Buffer不是现在的缓冲内容
if (SCount > 20) and isCapture and (dtime > 120 + 90) then
Begin
isCapture := false;
//Timer1.Enabled := true;
passTime := Round((BufSize - StartPos) * BufferTime / BufSize) + 90;
DoCapture(passTime);
End;
if stop then WaveInAddBuffer(WaveIn, PWaveHdr(Msg.lParam),
SizeOf(TWaveHdr))
else stop := true;
DoShowProgress(MaxValue);
//DoCapture(0);
end;
//打开音频捕捉
procedure TSoundCap.OpenCapture(handle : THandle);
var
header: TWaveFormatEx;
BufLen: word;
buf: pointer;
begin
BufSize := 3 * 500 + 100;//TrackBar1.Position * 500 + 100;
Bits16 := false;//CheckBox1.Checked;
with header do begin
wFormatTag := WAVE_FORMAT_PCM;
nChannels := 1;
nSamplesPerSec := 22050;
wBitsPerSample := integer(Bits16) * 8 + 8;
nBlockAlign := nChannels * (wBitsPerSample div 8 );
nAvgBytesPerSec := nSamplesPerSec * nBlockAlign;
cbSize := 0;
end;
WaveInOpen(Addr(WaveIn), WAVE_MAPPER, addr(header),
self.Handle , 0, CALLBACK_WINDOW);
BufLen := header.nBlockAlign * BufSize;
hBuf := GlobalAlloc(GMEM_MOVEABLE and GMEM_SHARE, BufLen);
Buf := GlobalLock(hBuf);
with BufHead do begin
lpData := Buf;
dwBufferLength := BufLen;
dwFlags := WHDR_BEGINLOOP;
end;
WaveInPrepareHeader(WaveIn, Addr(BufHead), sizeof(BufHead));
WaveInAddBuffer(WaveIn, addr(BufHead), sizeof(BufHead));
GetMem(p, BufSize * sizeof(TPoint));
GetMem(p2, BufSize * sizeof(TPoint));
stop := true;
WaveInStart(WaveIn);
StartTime := GetTickCount;
end;
//关闭音频捕捉
procedure TSoundCap.CloseCapture;
begin
if stop = false then Exit;
stop := false;
while not stop do Application.ProcessMessages;
//while not stop do sleep
stop := false;
WaveInReset(WaveIn);
WaveInUnPrepareHeader(WaveIn, addr(BufHead), sizeof(BufHead));
WaveInClose(WaveIn);
GlobalUnlock(hBuf);
GlobalFree(hBuf);
FreeMem(p, BufSize * sizeof(TPoint));
FreeMem(p2, BufSize * sizeof(TPoint));
end;
//开始监视捕捉, 并显示时间
procedure TSoundCap.StartCap;
begin
isCapture := true;
StartTime := GetTickCount;
end;
//停止监视音频捕捉
procedure TSoundCap.StopCap;
begin
isCapture := false;
end;
end.
interface
uses
Windows, Messages, MMSystem, Classes, SysUtils, Math, Forms, Controls;
Const
BufferTime : Real = 120; // 每次0.120秒 0.120 * 1000
type
TData8 = array [0..127] of byte;
PData8 = ^TData8;
TData16 = array [0..127] of smallint;
PData16 = ^TData16;
TPointArr = array [0..127] of TPoint;
PPointArr = ^TPointArr;
TShowProgressEvent = procedure (Sender: TObject; Position: Integer) of object;
TCaptureEvent = procedure (Sender: TObject; passTime : Integer) of Object;
TShowTimeEvent = procedure (Sender : TObject; Time : Integer) of Object;
TSoundCap = Class(TCustomControl)
private
FOnShowTime : TShowTimeEvent;
FOnShowProgress : TShowProgressEvent;
FOnCapture : TCaptureEvent;
function GetMidValue(i : Integer) : Integer; //计算中值
protected
procedure DoShowTime;//(Time : Integer); dynamic;
procedure DoShowProgress(position : Integer); dynamic;
procedure DoCapture(passTime : DWORD ); dynamic;
public
FilterValve : Integer; //音频过滤的阀值
isCapture : boolean ;
//constructor Create(AOwner: TComponent); overload;
constructor Create(handle : THandle); //overload;
destructor Destroy; override;
procedure OpenCapture(handle : THandle);
procedure CloseCapture;
procedure OnWaveIn(var Msg: TMessage); message MM_WIM_DATA;
procedure StartCap;
procedure StopCap;
property OnShowTime: TShowTimeEvent read FOnShowTime write FOnShowTime;
property OnShowProgress: TShowProgressEvent read FOnShowProgress write FOnShowProgress;
property OnCapture: TCaptureEvent read FOnCapture write FOnCapture;
end;
implementation
{ TSoundCap }
var
WaveIn: hWaveIn;
hBuf: THandle;
BufHead: TWaveHdr;
bufsize: integer;
Bits16: boolean;
p: PPointArr;
p2 : PPointArr;
stop: boolean = false;
StartTime : DWORD ;
Count : integer = 0;
constructor TSoundCap.Create(Handle : THandle);//(AOwner: TComponent);
begin
// ParentWindow := AOwner;
Inherited Create(nil);
ParentWindow := handle;
isCapture := false;
FilterValve := 3;
end;
destructor TSoundCap.Destroy;
begin
inherited;
CloseCapture;
end;
//触发捕获音频事件
procedure TSoundCap.DoCapture(passTime : DWORD );
var
EndTime : DWORD ;
begin
EndTime := GetTickCount;
if Assigned(FOnCapture) then FOnCapture(Self, EndTime - StartTime - passTime);
end;
//显示音频强度
procedure TSoundCap.DoShowProgress(position: Integer);
begin
if Assigned(FOnShowProgress) then FOnShowProgress(Self, position);
end;
//显示时间
procedure TSoundCap.DoShowTime;//(Time : Integer);
var
EndTime : DWORD ;
begin
EndTime := GetTickCount;
if Assigned(FOnShowTime) then FOnShowTime(Self, EndTime - StartTime);
end;
//中值过滤
function TSoundCap.GetMidValue(i: Integer): Integer;
var
v0,v1,v2 : integer;
h : integer;
mid : integer;
begin
h := 100;
v0 := p^[i-2].Y;
v1 := p^[i-1].Y;
v2 := p^[i].Y;
mid := (v0 + v1 + v2) div 3;
if abs(abs(mid) - v1) > FilterValve then
Result := mid
Else if abs(mid - h/2) < FilterValve then
Result := 0
Else
Result := v1;
end;
//处理Wave数据采集
procedure TSoundCap.OnWaveIn(var Msg: TMessage);
var
data8 : PData8;
i, x, y : integer;
StartPos, EndPos, SCount : integer;
passTime , MaxValue , tmp : Integer;
dtime : DWORD;
begin
//DoCapture(0);
MaxValue := 0;
Data8 := PData8(PWaveHdr(Msg.lParam)^.lpData);
//将Buffer中采集的数据存入 P 中
for i := 0 to BufSize - 1 do
Begin
x := i;
y := Round(abs(data8^[i] - 128) * 100 / 128); //data8^[i] 为 128 - 256 之间
p^[i] := Point(x, y);
//计算滤波后的值 , 滤波之后的数据存入 P2 中
if (i > 1) and (i < BufSize ) then
Begin
p2^[i] := Point(p^[i].X, GetMidValue(i));
end;
//p2^[i] := GetMidValue(x,y,i);
//Inc(count,data8^[i]);
//count := count + Round(abs(data8^[i] - 128) * 100 / 128);
//ShowProgress(Round(count / BufSize));
tmp := Round(abs(data8^[i] - 128) * 100 / 128);
if tmp > MaxValue Then
MaxValue := tmp;
//count := count + tmp;
End;
p2^[0] := Point(p^[0].X, GetMidValue(2));
p2^[1] := Point(p^[0].X, GetMidValue(2));
//Caption := IntToStr(count div BufSize);
//不需要绘画音频曲线
{
with PaintBox1.Canvas do begin
Brush.Color := clBlack;
Pen.Color := clGreen;
FillRect(ClipRect);
Polyline(Slice(p^, BufSize));
end;
with PaintBox2.Canvas do begin
Brush.Color := clBlack;
Pen.Color := clGreen;
FillRect(ClipRect);
Polyline(Slice(p2^, BufSize));
end;
}
//判断是否有超出域值的数据
StartPos := 0;
EndPos := 0;
SCount := 0;
for I := 0 to BufSize - 1 do
begin
if abs(p2^[i].Y ) > FilterValve then
Begin
if StartPos = 0 then
StartPos := i;
Inc(SCount);
end Else if StartPos = 0 then
p^[i].Y := 0;//h div 2;
if (SCount > 20) then
if (EndPos = 0) then
EndPos := Min((StartPos + BufSize div 2 ) , BufSize - 1)
Else if EndPos < i then
p^[i].Y := 0;//h div 2;
end;
{
if (SCount > 20) and isCapture then
with PaintBox3.Canvas do begin
Brush.Color := clBlack;
Pen.Color := clGreen;
FillRect(ClipRect);
Polyline(Slice(p^, BufSize));
isCapture := false;
Timer1.Enabled := true;
passTime := Round(StartPos * BufferTime / BufSize);
RecordTime(passTime);
end; }
//Show Time
If isCapture Then DoShowTime();
//SCount := 100;
//StartPos := 0;
//如果有音频超出阀值，并且正在捕捉，则记录具体时间
dtime := GetTickCount - StartTime;
//如果说 dtime < 120 , 则这个Buffer不是现在的缓冲内容
if (SCount > 20) and isCapture and (dtime > 120 + 90) then
Begin
isCapture := false;
//Timer1.Enabled := true;
passTime := Round((BufSize - StartPos) * BufferTime / BufSize) + 90;
DoCapture(passTime);
End;
if stop then WaveInAddBuffer(WaveIn, PWaveHdr(Msg.lParam),
SizeOf(TWaveHdr))
else stop := true;
DoShowProgress(MaxValue);
//DoCapture(0);
end;
//打开音频捕捉
procedure TSoundCap.OpenCapture(handle : THandle);
var
header: TWaveFormatEx;
BufLen: word;
buf: pointer;
begin
BufSize := 3 * 500 + 100;//TrackBar1.Position * 500 + 100;
Bits16 := false;//CheckBox1.Checked;
with header do begin
wFormatTag := WAVE_FORMAT_PCM;
nChannels := 1;
nSamplesPerSec := 22050;
wBitsPerSample := integer(Bits16) * 8 + 8;
nBlockAlign := nChannels * (wBitsPerSample div 8 );
nAvgBytesPerSec := nSamplesPerSec * nBlockAlign;
cbSize := 0;
end;
WaveInOpen(Addr(WaveIn), WAVE_MAPPER, addr(header),
self.Handle , 0, CALLBACK_WINDOW);
BufLen := header.nBlockAlign * BufSize;
hBuf := GlobalAlloc(GMEM_MOVEABLE and GMEM_SHARE, BufLen);
Buf := GlobalLock(hBuf);
with BufHead do begin
lpData := Buf;
dwBufferLength := BufLen;
dwFlags := WHDR_BEGINLOOP;
end;
WaveInPrepareHeader(WaveIn, Addr(BufHead), sizeof(BufHead));
WaveInAddBuffer(WaveIn, addr(BufHead), sizeof(BufHead));
GetMem(p, BufSize * sizeof(TPoint));
GetMem(p2, BufSize * sizeof(TPoint));
stop := true;
WaveInStart(WaveIn);
StartTime := GetTickCount;
end;
//关闭音频捕捉
procedure TSoundCap.CloseCapture;
begin
if stop = false then Exit;
stop := false;
while not stop do Application.ProcessMessages;
//while not stop do sleep
stop := false;
WaveInReset(WaveIn);
WaveInUnPrepareHeader(WaveIn, addr(BufHead), sizeof(BufHead));
WaveInClose(WaveIn);
GlobalUnlock(hBuf);
GlobalFree(hBuf);
FreeMem(p, BufSize * sizeof(TPoint));
FreeMem(p2, BufSize * sizeof(TPoint));
end;
//开始监视捕捉, 并显示时间
procedure TSoundCap.StartCap;
begin
isCapture := true;
StartTime := GetTickCount;
end;
//停止监视音频捕捉
procedure TSoundCap.StopCap;
begin
isCapture := false;
end;
end.
具体调用：
SoundCap := TSoundCap.Create(self.Handle);
SoundCap.OnShowProgress := OnSoundPosition;
SoundCap.OnShowTime := OnShowTime;
SoundCap.OnCapture := OnCapture;
SoundCap.OpenCapture(MainForm.Handle);
..
SoundCap.CloseCapture;
SoundCap.OnShowProgress := OnSoundPosition;
SoundCap.OnShowTime := OnShowTime;
SoundCap.OnCapture := OnCapture;
SoundCap.OpenCapture(MainForm.Handle);
..SoundCap.CloseCapture;
