/*窗类型*/
typedef enum
{
Bartlett = 0,
BartLettHann,
BlackMan,
BlackManHarris,
Bohman,
Chebyshev,
FlatTop,
Gaussian,
Hamming,
Hann,
Kaiser,
Nuttal,
Parzen,
Rectangular,
Taylor,
Triangular,
Tukey
}winType;
/*
*file WindowFunction.h
*author Vincent Cui
*e-mail whcui1987@163.com
*version 0.3
*data 31-Oct-2014
*brief 各种窗函数的C语言实现
*/
#ifndef _WINDOWFUNCTION_H_
#define _WINDOWFUNCTION_H_
#include "GeneralConfig.h"
#define BESSELI_K_LENGTH 10
#define FLATTOPWIN_A0 0.215578995
#define FLATTOPWIN_A1 0.41663158
#define FLATTOPWIN_A2 0.277263158
#define FLATTOPWIN_A3 0.083578947
#define FLATTOPWIN_A4 0.006947368
#define NUTTALL_A0 0.3635819
#define NUTTALL_A1 0.4891775
#define NUTTALL_A2 0.1365995
#define NUTTALL_A3 0.0106411
#define BLACKMANHARRIS_A0 0.35875
#define BLACKMANHARRIS_A1 0.48829
#define BLACKMANHARRIS_A2 0.14128
#define BLACKMANHARRIS_A3 0.01168
dspErrorStatus taylorWin(dspUint_16 N, dspUint_16 nbar, dspDouble sll, dspDouble **w);
dspErrorStatus triangularWin(dspUint_16 N, dspDouble **w);
dspErrorStatus tukeyWin(dspUint_16 N, dspDouble r, dspDouble **w);
dspErrorStatus bartlettWin(dspUint_16 N, dspDouble **w);
dspErrorStatus bartLettHannWin(dspUint_16 N, dspDouble **w);
dspErrorStatus blackManWin(dspUint_16 N, dspDouble **w);
dspErrorStatus blackManHarrisWin(dspUint_16 N, dspDouble **w);
dspErrorStatus bohmanWin(dspUint_16 N, dspDouble **w);
dspErrorStatus chebyshevWin(dspUint_16 N, dspDouble r, dspDouble **w);
dspErrorStatus flatTopWin(dspUint_16 N, dspDouble **w);
dspErrorStatus gaussianWin(dspUint_16 N, dspDouble alpha, dspDouble **w);
dspErrorStatus hammingWin(dspUint_16 N, dspDouble **w);
dspErrorStatus hannWin(dspUint_16 N, dspDouble **w);
dspErrorStatus kaiserWin(dspUint_16 N, dspDouble beta, dspDouble **w);
dspErrorStatus nuttalWin(dspUint_16 N, dspDouble **w);
dspErrorStatus parzenWin(dspUint_16 N, dspDouble **w);
dspErrorStatus rectangularWin(dspUint_16 N, dspDouble **w);
#endif
WindowFunction.h
/*
*file WindowFunction.c
*author Vincent Cui
*e-mail whcui1987@163.com
*version 0.3
*data 31-Oct-2014
*brief 各种窗函数的C语言实现
*/
#include "WindowFunction.h"
#include "GeneralConfig.h"
#include "MathReplenish.h"
#include "math.h"
#include
#include
#include
/*函数名：taylorWin
*说明：计算泰勒窗。泰勒加权函数
*输入：
*输出：
*返回：
*调用：prod()连乘函数
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = taylorWin(99, 4, 40, &w); 注意此处的40是正数 表示-40dB
*/
dspErrorStatus taylorWin(dspUint_16 N, dspUint_16 nbar, dspDouble sll, dspDouble **w)
{
dspDouble A;
dspDouble *retDspDouble;
dspDouble *sf;
dspDouble *result;
dspDouble alpha,beta,theta;
dspUint_16 i,j;
/*A = R cosh(PI, A) = R*/
A = (dspDouble)acosh(pow((dspDouble)10.0,(dspDouble)sll/20.0)) / PI;
A = A * A;
/*开出存放系数的空间*/
retDspDouble = (dspDouble *)malloc(sizeof(dspDouble) * (nbar - 1));
if(retDspDouble == NULL)
return DSP_ERROR;
sf = retDspDouble;
/*开出存放系数的空间*/
retDspDouble = (dspDouble *)malloc(sizeof(dspDouble) * N);
if(retDspDouble == NULL)
return DSP_ERROR;
result = retDspDouble;
alpha = prod(1, 1, (nbar - 1));
alpha *= alpha;
beta = (dspDouble)nbar / sqrt( A + pow((nbar - 0.5), 2) );
for(i = 1; i <= (nbar - 1); i++)
{
*(sf + i - 1) = prod(1,1,(nbar -1 + i)) * prod(1,1,(nbar -1 - i));
theta = 1;
for(j = 1; j <= (nbar - 1); j++)
{
theta *= 1 - (dspDouble)(i * i) / ( beta * beta * ( A + (j - 0.5) * (j - 0.5)) );
}
*(sf + i - 1) = alpha * (dspDouble)theta / (*(sf + i - 1));
}
/*奇数阶*/
if((N % 2) == 1)
{
for(i = 0; i < N; i++)
{
alpha = 0;
for(j = 1; j <= (nbar - 1); j++)
{
alpha += (*(sf + j - 1)) * cos( 2 * PI * j * (dspDouble)(i - ((N-1)/2))/N );
}
*(result + i) = 1 + 2 * alpha;
}
}
/*偶数阶*/
else
{
for(i = 0; i < N; i++)
{
alpha = 0;
for(j = 1; j <= (nbar - 1); j++)
{
alpha += (*(sf + j - 1)) * cos( PI * j * (dspDouble)(2 * (i - (N/2)) + 1) / N );
}
*(result + i) = 1 + 2 * alpha;
}
}
*w = result;
free(sf);
return DSP_SUCESS;
}
/*
*函数名：triangularWin
*说明：计算三角窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = triangularWin(99, &w);
*/
dspErrorStatus triangularWin(dspUint_16 N, dspDouble **w)
{
dspDouble *ptr;
dspUint_16 i;
ptr = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ptr == NULL)
return DSP_ERROR;
/*阶数为奇*/
if((N % 2) == 1)
{
for(i = 0; i < ((N - 1)/2); i++)
{
*(ptr + i) = 2 * (dspDouble)(i + 1) / (N + 1);
}
for(i = ((N - 1)/2); i < N; i++)
{
*(ptr + i) = 2 * (dspDouble)(N - i) / (N + 1);
}
}
/*阶数为偶*/
else
{
for(i = 0; i < (N/2); i++)
{
*(ptr + i) = (i + i + 1) * (dspDouble)1 / N;
}
for(i = (N/2); i < N; i++)
{
*(ptr + i) = *(ptr + N - 1 - i);
}
}
*w = ptr;
return DSP_SUCESS;
}
/*
*函数名：tukeyWin
*说明：计算tukey窗函数
*输入：
*输出：
*返回：linSpace()
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = tukeyWin(99, 0.5, &w);
*/
dspErrorStatus tukeyWin(dspUint_16 N, dspDouble r, dspDouble **w)
{
dspErrorStatus retErrorStatus;
dspUint_16 index;
dspDouble *x,*result,*retPtr;
dspDouble alpha;
retErrorStatus = linSpace(0, 1, N, &x);
if(retErrorStatus == DSP_ERROR)
return DSP_ERROR;
result = (dspDouble *)malloc(N * sizeof(dspDouble));
if(result == NULL)
return DSP_ERROR;
/*r <= 0 就是矩形窗*/
if(r <= 0)
{
retErrorStatus = rectangularWin(N, &retPtr);
if(retErrorStatus == DSP_ERROR)
return DSP_ERROR;
/*将数据拷出来以后，释放调用的窗函数的空间*/
memcpy(result, retPtr, ( N * sizeof(dspDouble)));
free(retPtr);
}
/*r >= 1 就是汉宁窗*/
else if(r >= 1)
{
retErrorStatus = hannWin(N, &retPtr);
if(retErrorStatus == DSP_ERROR)
return DSP_ERROR;
/*将数据拷出来以后，释放调用的窗函数的空间*/
memcpy(result, retPtr, ( N * sizeof(dspDouble)));
free(retPtr);
}
else
{
for(index = 0; index < N; index++)
{
alpha = *(x + index);
if(alpha < (r/2))
{
*(result + index) = (dspDouble)(1 + cos( 2 * PI * (dspDouble)(alpha - (dspDouble)r/2)/r))/2;
}
else if((alpha >= (r/2)) && (alpha <(1 - r/2)))
{
*(result + index) = 1;
}
else
{
*(result + index) = (dspDouble)(1 + cos( 2 * PI * (dspDouble)(alpha - 1 + (dspDouble)r/2)/r))/2;
}
}
}
free(x);
*w = result;
return DSP_SUCESS;
}
/*
*函数名：bartlettWin
*说明：计算bartlettWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = bartlettWin(99, &w);
*/
dspErrorStatus bartlettWin(dspUint_16 N, dspDouble **w)
{
dspDouble *ret;
dspUint_16 n;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n = 0; n < ( N - 1 ) / 2; n++)
{
*(ret + n) = 2 * (dspDouble)n / (N - 1);
}
for(n = ( N - 1 ) / 2; n < N; n++)
{
*(ret + n) = 2 - 2 * (dspDouble)n / (( N - 1 ));
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：bartLettHannWin
*说明：计算bartLettHannWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = bartLettHannWin(99, &w);
*/
dspErrorStatus bartLettHannWin(dspUint_16 N, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
/*奇*/
if(( N % 2 ) == 1)
{
for(n = 0; n < N; n++)
{
*(ret + n) = 0.62 - 0.48 * myAbs( ( (dspDouble)n / ( N - 1 ) ) - 0.5 ) + 0.38 * cos( 2 * PI * ( ((dspDouble)n / ( N - 1 ) ) - 0.5 ) );
}
for(n = 0; n < (N-1)/2; n++)
{
*(ret + n) = *(ret + N - 1 - n);
}
}
/*偶*/
else
{
for(n = 0; n < N; n++)
{
*(ret + n) = 0.62 - 0.48 * myAbs( ( (dspDouble)n / ( N - 1 ) ) - 0.5 ) + 0.38 * cos( 2 * PI * ( ((dspDouble)n / ( N - 1 ) ) - 0.5 ) );
}
for(n = 0; n < N/2; n++)
{
*(ret + n) = *(ret + N -1 - n);
}
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：blackManWin
*说明：计算blackManWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = blackManWin(99, &w);
*/
dspErrorStatus blackManWin(dspUint_16 N, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n = 0; n < N; n++)
{
*(ret + n) = 0.42 - 0.5 * cos(2 * PI * (dspDouble)n / ( N - 1 )) + 0.08 * cos( 4 * PI * ( dspDouble )n / ( N - 1 ) );
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：blackManHarrisWin
*说明：计算blackManHarrisWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = blackManHarrisWin(99, &w);
* minimum 4-term Blackman-harris window -- From Matlab
*/
dspErrorStatus blackManHarrisWin(dspUint_16 N, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n = 0; n < N; n++)
{
*(ret + n) = BLACKMANHARRIS_A0 - BLACKMANHARRIS_A1 * cos( 2 * PI * (dspDouble)n / (N) ) + \
BLACKMANHARRIS_A2 * cos( 4 * PI * (dspDouble)n/ (N) ) - \
BLACKMANHARRIS_A3 * cos( 6 * PI * (dspDouble)n/ (N) );
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：bohmanWin
*说明：计算bohmanWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = bohmanWin(99, &w);
*/
dspErrorStatus bohmanWin(dspUint_16 N, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
dspDouble x;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n = 0; n < N; n++)
{
x = -1 + n * (dspDouble)2 / ( N - 1 ) ;
/*取绝对值*/
x = x >= 0 ? x : ( x * ( -1 ) );
*(ret + n) = ( 1 - x ) * cos( PI * x) + (dspDouble)(1 / PI) * sin( PI * x);
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：chebyshevWin
*说明：计算chebyshevWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = chebyshevWin(99,100, &w);
*/
dspErrorStatus chebyshevWin(dspUint_16 N, dspDouble r, dspDouble **w)
{
dspUint_16 n,index;
dspDouble *ret;
dspDouble x, alpha, beta, theta, gama;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
/*10^(r/20)*/
theta = pow((dspDouble)10, (dspDouble)(myAbs(r)/20));
beta = pow(cosh(acosh(theta)/(N - 1)),2);
alpha = 1 - (dspDouble)1 / beta;
if((N % 2) == 1)
{
/*计算一半的区间*/
for( n = 1; n < ( N + 1 ) / 2; n++ )
{
gama = 1;
for(index = 1; index < n; index++)
{
x = index * (dspDouble)( N - 1 - 2 * n + index) /(( n - index ) * (n + 1 -index));
gama = gama * alpha * x + 1;
}
*(ret + n) = (N - 1) * alpha * gama;
}
theta = *( ret + (N - 1)/2 );
*ret = 1;
for(n = 0; n < ( N + 1 ) / 2; n++ )
{
*(ret + n) = (dspDouble)(*(ret + n)) / theta;
}
/*填充另一半*/
for(; n < N; n++)
{
*(ret + n) = ret[N - n - 1];
}
}
else
{
/*计算一半的区间*/
for( n = 1; n < ( N + 1 ) / 2; n++ )
{
gama = 1;
for(index = 1; index < n; index++)
{
x = index * (dspDouble)( N - 1 - 2 * n + index) /(( n - index ) * (n + 1 -index));
gama = gama * alpha * x + 1;
}
*(ret + n) = (N - 1) * alpha * gama;
}
theta = *( ret + (N/2) - 1);
*ret = 1;
for(n = 0; n < ( N + 1 ) / 2; n++ )
{
*(ret + n) = (dspDouble)(*(ret + n)) / theta;
}
/*填充另一半*/
for(; n < N; n++)
{
*(ret + n) = ret[N - n - 1];
}
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：flatTopWin
*说明：计算flatTopWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = flatTopWin(99, &w);
*/
dspErrorStatus flatTopWin(dspUint_16 N, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n = 0; n < N; n++)
{
*(ret + n) = FLATTOPWIN_A0 - FLATTOPWIN_A1 * cos(2 * PI * (dspDouble)n / (N - 1)) +\
FLATTOPWIN_A2 * cos(4 * PI * (dspDouble)n / (N - 1)) -\
FLATTOPWIN_A3 * cos(6 * PI * (dspDouble)n / (N - 1)) +\
FLATTOPWIN_A4 * cos(8 * PI * (dspDouble)n / (N - 1));
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：gaussianWin
*说明：计算gaussianWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = gaussianWin(99,2.5, &w);
*/
dspErrorStatus gaussianWin(dspUint_16 N, dspDouble alpha, dspDouble **w)
{
dspUint_16 n;
dspDouble k, beta, theta;
dspDouble *ret;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n =0; n < N; n++)
{
if((N % 2) == 1)
{
k = n - (N - 1)/2;
beta = 2 * alpha * (dspDouble)k / (N - 1);
}
else
{
k = n - (N)/2;
beta = 2 * alpha * (dspDouble)k / (N - 1);
}
theta = pow(beta, 2);
*(ret + n) = exp((-1) * (dspDouble)theta / 2);
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：hammingWin
*说明：计算hammingWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = hammingWin(99, &w);
*/
dspErrorStatus hammingWin(dspUint_16 N, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n = 0; n < N; n++)
{
*(ret + n) = 0.54 - 0.46 * cos (2 * PI * ( dspDouble )n / ( N - 1 ) );
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：hannWin
*说明：计算hannWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = hannWin(99, &w);
*/
dspErrorStatus hannWin(dspUint_16 N, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n = 0; n < N; n++)
{
*(ret + n) = 0.5 * ( 1 - cos( 2 * PI * (dspDouble)n / (N - 1)));
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：kaiserWin
*说明：计算kaiserWin窗函数
*输入：
*输出：
*返回：
*调用：besseli()第一类修正贝塞尔函数
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = kaiserWin(99, 5, &w);
*/
dspErrorStatus kaiserWin(dspUint_16 N, dspDouble beta, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
dspDouble theta;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n = 0; n < N; n++)
{
theta = beta * sqrt( 1 - pow( ( (2 * (dspDouble)n/(N -1)) - 1),2 ) );
*(ret + n) = (dspDouble)besseli(0, theta, BESSELI_K_LENGTH) / besseli(0, beta, BESSELI_K_LENGTH);
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：nuttalWin
*说明：计算nuttalWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = nuttalWin(99, &w);
*/
dspErrorStatus nuttalWin(dspUint_16 N, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n = 0; n < N; n++)
{
*(ret + n) =NUTTALL_A0 - NUTTALL_A1 * cos(2 * PI * (dspDouble)n / (N - 1)) +\
NUTTALL_A2 * cos(4 * PI * (dspDouble)n / (N - 1)) -\
NUTTALL_A3 * cos(6 * PI * (dspDouble)n / (N - 1));
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：parzenWin
*说明：计算parzenWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = parzenWin(99, &w);
*/
dspErrorStatus parzenWin(dspUint_16 N, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
dspDouble alpha,k;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
if(( N % 2) == 1)
{
for(n = 0; n < N; n++)
{
k = n - (N - 1) / 2;
alpha = 2 * (dspDouble)myAbs(k) / N;
if(myAbs(k) <= (N - 1) / 4)
{
*(ret + n) = 1 - 6 * pow(alpha,2) + 6 * pow(alpha, 3);
}
else
{
*(ret + n) = 2 * pow( (1 - alpha), 3 );
}
}
}
else
{
for(n = 0; n < N; n++)
{
k = n - (N - 1) / 2;
alpha = 2 * (dspDouble)myAbs(k) / N;
if(myAbs(k) <= (dspDouble)(N -1) / 4)
{
*(ret + n) = 1 - 6 * pow(alpha,2) + 6 * pow(alpha, 3);
}
else
{
*(ret + n) = 2 * pow( (1 - alpha), 3 );
}
}
}
*w = ret;
return DSP_SUCESS;
}
/*
*函数名：rectangularWin
*说明：计算rectangularWin窗函数
*输入：
*输出：
*返回：
*调用：
*其它：用过以后，需要手动释放掉*w的内存空间
* 调用示例：ret = rectangularWin(99, &w);
*/
dspErrorStatus rectangularWin(dspUint_16 N, dspDouble **w)
{
dspUint_16 n;
dspDouble *ret;
ret = (dspDouble *)malloc(N * sizeof(dspDouble));
if(ret == NULL)
return DSP_ERROR;
for(n = 0; n < N; n++)
{
*(ret + n) = 1;
}
*w = ret;
return DSP_SUCESS;
}
WindowFunction.c
畅学电子
