windowfilterview.cpp

数字信号处理实验

// windowFilterView.cpp : implementation of the CWindowFilterView class
//

#include "stdafx.h"
#include "windowFilter.h"

#include "windowFilterDoc.h"
#include "windowFilterView.h"
#include "math.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

#define PI 3.14159
/////////////////////////////////////////////////////////////////////////////
// CWindowFilterView

IMPLEMENT_DYNCREATE(CWindowFilterView, CFormView)

BEGIN_MESSAGE_MAP(CWindowFilterView, CFormView)
	//{{AFX_MSG_MAP(CWindowFilterView)
	ON_CBN_SELCHANGE(IDC_WINDOWTIPE, OnSelchangeWindowtipe)
	ON_CBN_SELCHANGE(IDC_FILTERTYPE, OnSelchangeFiltertype)
	ON_BN_CLICKED(IDC_BTN_DRAW, OnBtnDraw)
	ON_WM_PAINT()
	//}}AFX_MSG_MAP
	// Standard printing commands
	ON_COMMAND(ID_FILE_PRINT, CFormView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_DIRECT, CFormView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_PREVIEW, CFormView::OnFilePrintPreview)
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CWindowFilterView construction/destruction

CWindowFilterView::CWindowFilterView()
	: CFormView(CWindowFilterView::IDD)
{
	//{{AFX_DATA_INIT(CWindowFilterView)
	m_WindowLength = 8;
	m_WcLow = 0.4f;
	m_WcHigh = 0.5f;
	m_iWindowType = 0;
	m_iFilterType = 0;
	m_bety = 0.5f;
	pHdImag = NULL;
	pHdReal = NULL;
	pReal = NULL;
	pImag = NULL;
	pWindowImag = NULL;
	pWindowReal = NULL;
	m_bFirst = FALSE;
	m_bClean = FALSE;
	//}}AFX_DATA_INIT
	// TODO: add construction code here
}

CWindowFilterView::~CWindowFilterView()
{
}

void CWindowFilterView::DoDataExchange(CDataExchange* pDX)
{
	CFormView::DoDataExchange(pDX);
	//{{AFX_DATA_MAP(CWindowFilterView)
	DDX_Text(pDX, IDC_WINDOWLENGTH, m_WindowLength);
	DDV_MinMaxInt(pDX, m_WindowLength, 1, 100);
	DDX_Text(pDX, IDC_EDIT_LOW, m_WcLow);
	DDX_Text(pDX, IDC_EDIT_HIGH, m_WcHigh);
	DDX_Text(pDX, IDC_EDIT_BETY, m_bety);
	//}}AFX_DATA_MAP
}

BOOL CWindowFilterView::PreCreateWindow(CREATESTRUCT& cs)
{
	// TODO: Modify the Window class or styles here by modifying
	//  the CREATESTRUCT cs

	return CFormView::PreCreateWindow(cs);
}

void CWindowFilterView::OnInitialUpdate()
{
	((CComboBox *)GetDlgItem (IDC_FILTERTYPE))->SetCurSel(0);
	((CComboBox *)GetDlgItem (IDC_WINDOWTIPE))->SetCurSel(0);
	(CStatic *)GetDlgItem(IDC_HIGHWC)->EnableWindow(false);
	(CStatic *)GetDlgItem(IDC_STATIC_BETY)->EnableWindow(false);
	(CEdit *)GetDlgItem(IDC_EDIT_BETY)->EnableWindow(false);
	(CEdit *)GetDlgItem(IDC_EDIT_HIGH)->EnableWindow(false);
	CFormView::OnInitialUpdate();
	GetParentFrame()->RecalcLayout();
	ResizeParentToFit();
}

/////////////////////////////////////////////////////////////////////////////
// CWindowFilterView printing

BOOL CWindowFilterView::OnPreparePrinting(CPrintInfo* pInfo)
{
	// default preparation
	return DoPreparePrinting(pInfo);
}

void CWindowFilterView::OnBeginPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
	// TODO: add extra initialization before printing
}

void CWindowFilterView::OnEndPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
	// TODO: add cleanup after printing
}

void CWindowFilterView::OnPrint(CDC* pDC, CPrintInfo* /*pInfo*/)
{
	// TODO: add customized printing code here
	if (m_bFirst == FALSE)
	{
		m_bFirst = TRUE;
	}
	else
	{
		OnBtnDraw();
	}
}

/////////////////////////////////////////////////////////////////////////////
// CWindowFilterView diagnostics

#ifdef _DEBUG
void CWindowFilterView::AssertValid() const
{
	CFormView::AssertValid();
}

void CWindowFilterView::Dump(CDumpContext& dc) const
{
	CFormView::Dump(dc);
}

CWindowFilterDoc* CWindowFilterView::GetDocument() // non-debug version is inline
{
	ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CWindowFilterDoc)));
	return (CWindowFilterDoc*)m_pDocument;
}
#endif //_DEBUG

/////////////////////////////////////////////////////////////////////////////
// CWindowFilterView message handlers

// 生成模值
// 入口参数：数组名和长度
// Xabs:     存储模值的数组名，相当与返回值
// Xreal:    存储实部的数组名
// Ximag:    存储虚部的数组名
// n:	     数组的长度
void CWindowFilterView::CreateAbs(float *Xabs, float *Xreal, float *Ximag, int n)
{
	int i;
	for(i=0; i<n; i++)
	{
		Xabs[i] = sqrt(Xreal[i]*Xreal[i] + Ximag[i]*Ximag[i]);
		Xabs[i] = 20 * log10f(Xabs[i] + 1E-8);     //化为db表示
	}
}

// 入口参数：数组名和长度
// Xarg:     存储角度的数组名，相当与返回值
// Xreal:    存储实部的数组名
// Ximag:    存储虚部的数组名
// n:	     数组的长度
void CWindowFilterView::CreateArg(float *Xarg, float *Xreal, float *Ximag, int n)
{
	int i;
	for(i=0; i<n; i++)
	{
		Xarg[i] = atan2(Ximag[i],Xreal[i]);
	}
}

// 倒位排序函数
// j为正常序列的下标
// nu为长度的log2（长度），长度为16，则为4
// nu在以后要改为长度 count
int CWindowFilterView::ibitr(int j, int count)
{
	int b,j1,i,j2,nu;
	int nu1;
	nu = 0;
	nu1 = count;
	while (nu1 / 2)
	{
		nu1 /= 2;
		nu ++;
	}	
	j1 = j;
	b = 0;
	for (i=1; i<=nu; i++)
	{
		j2 = j1/2;
		b = b*2 + (j1-2*j2);
		j1 = j2;
	}
	return b;
}

// 生成FFT变换的实部和虚部，
// 入口参数：数组名和长度
// Xreal:    存储FFT结果实部的数组名,相当与返回值
// Ximag:    存储FFT结果虚部的数组名,相当于返回值
// xreal:    存储时间序列实部的数组名
// ximga:    存储时间序列虚部的数组名
// n:	     窗口的长度
// 返回值为FFT的实际长度
// 以后可能要改为引用名
int CWindowFilterView::CreateFFT(float *Xreal, float *Ximag, float *xreal, float *ximag, int n)
{	
	int i,j,k,l,m,deta,p,a;	
	float treal,timag,temp;
	int m_FFTLengthTemp;
	//补成2的 n 次方倍数
	i=1;
	while (pow(2,i)<n)
	{
		i++;
	}
	m_FFTLengthTemp = pow(2,i);     //将长度修改 
	if (m_FFTLengthTemp < 256)
	{
		m_FFTLengthTemp = 256;          //本题中将长度先定为128
	}
	
//  以后要用的时候，在View类中改为指针。将值改为Xreal，名字为引用
//	就行了 
// 	if (Xreal != NULL)
// 	{
// 		delete []Xreal;
// 		Xreal = NULL;
// 	}
// 	if (Ximag != NULL)
// 	{
// 		delete []Ximag;
// 		Ximag = NULL;
// 	}
//	float * //Xreal = new float [m_FFTLengthTemp];
// 	float * //Ximag = new float [m_FFTLengthTemp];

	//赋值函数,先全部清零
	memset(Xreal, 0, sizeof(float)*m_FFTLengthTemp);
	memset(Ximag, 0, sizeof(float)*m_FFTLengthTemp);
	for (i = 0; i<n; i++)
	{
		Xreal[i] = xreal[i];
		Ximag[i] = ximag[i];
	}
	//倒位函数，交换数组内容
	for (i = 0; i<m_FFTLengthTemp; i++)
	{
		j = ibitr(i, m_FFTLengthTemp);
		if (j > i)
		{
			temp = Xreal[i];
			Xreal[i] = Xreal[j];
			Xreal[j] = temp;
			temp = Ximag[i];
			Ximag[i] = Ximag[j];
			Ximag[j] = temp;
		}
	}
	//FFT蝶形运算
	a = 0;
	k = m_FFTLengthTemp;
	while (k = k/2)
	{
		deta = (int)pow(2,a);		
		l = 0; 
		m = 0;
		for(i = 0; i < k; i++)
		{			
			for(j = 0; j < deta; j++)   //　l　和　l+deta 的蝶形运算
			{
				p = j * k;
				treal = Xreal[l+deta] * cos(2*PI/m_FFTLengthTemp*p)
					+ Ximag[l+deta] * sin(2*PI/m_FFTLengthTemp*p);
				timag = Ximag[l+deta] * cos(2*PI/m_FFTLengthTemp*p)
					- Xreal[l+deta] * sin(2*PI/m_FFTLengthTemp*p);
				Xreal[l+deta] = Xreal[l] - treal;
				Ximag[l+deta] = Ximag[l] - timag;
				Xreal[l] = Xreal[l] + treal;
				Ximag[l] = Ximag[l] + timag;
				l++;
			}
			m += deta * 2;
			l = m;
		}
		a++;
	}
// 	delete []xrealTemp;
// 	delete []ximagTemp;
	return m_FFTLengthTemp;

}

// 利用FFT生成IFFT变换的实部和虚部，
// 入口参数：数组名和长度
// xreal:    存储IFFT结果实部的数组名,相当与返回值
// ximag:    存储IFFT结果虚部的数组名,相当于返回值
// Xreal:    存储频率序列实部的数组名
// Ximga:    存储频率序列虚部的数组名
// n:	     数组的长度
void CWindowFilterView::CreateIFFT( float *xreal, float *ximag, float *Xreal, float *Ximag, int &n)
{
	int i;
	//赋值函数
	//求共轭复数
	for (i = 0; i<n; i++)
	{
		xreal[i] = Xreal[i];
		ximag[i] = -Ximag[i];
	}
	CreateFFT(xreal, ximag, xreal, ximag, n);
	for (i = 0; i<n; i++)
	{
		xreal[i] = xreal[i] / n;
		ximag[i] = -ximag[i] / n;
	}
}

//求最大绝对值
float CWindowFilterView::mymax(float *a, int n)
{
	int i;
	float *b = a;
	float num = 0;
	for (i=0; i<n; i++)
	{
		if(fabs(*b) > num)
			num = fabs(*b);
		b++;
	}
 	return num;
}

//矩形窗
void CWindowFilterView::CreateRect(float *real, float *imag, int n)
{
	int i;
	for (i=0; i<n; i++)
	{
		real[i] = 1.0;
		imag[i] = 0.0;
	}
}

//三角形窗
void CWindowFilterView::CreateTriang(float *real, float *imag, int n)
{
	int i;
	float m = n;
	for (i=0; i<=(n-1)/2; i++)
	{
		real[i] = 2*i/(m-1);
		imag[i] = 0;
	}
	for (; i < n; i++)
	{
		real[i] = 2 - 2*i/(m-1);
		imag[i] = 0;
	}
}

//Hanning窗
void CWindowFilterView::CreateHanning(float *real, float *imag, int n)
{
	int i;
	for (i=0; i<n; i++)
	{
		real[i] = 0.5 * (1 - cos(2*PI*i/(n-1))) ;
		imag[i] = 0.0;
	}
}

//Hamming窗
void CWindowFilterView::CreateHamming(float *real, float *imag, int n)
{
	int i;
	for (i=0; i<n; i++)
	{
		real[i] = 0.54 - 0.46 * cos(2*PI*i/(n-1)) ;
		imag[i] = 0.0;
	}
}

//Blackman窗
void CWindowFilterView::CreateBlackman(float *real, float *imag, int n)
{
	int i;
	for (i=0; i<n; i++)
	{
		real[i] = 0.42 - 0.5 * cos(2*PI*i / (n-1)) + 0.08 * cos(4*PI*i / (n-1)) ;
		imag[i] = 0.0;
	}	
}
//零阶贝塞尔函数，系数为x
float CWindowFilterView::ino(float x)
{
	float y,t,e,de,sde,xi;
	int i;
	y = x / 2;
	t = 1.e-08;
	e = 1.0;
	de = 1.0;
	for (i=1; i<=25; i++)
	{
		xi = i;
		de = de*y/xi;
		sde = de*de;
		e = e + sde;
		if ((e*t-sde) > 0)
		{
			break;
		}
	}
	return e;
}


//Kaiser窗
void CWindowFilterView::CreateKaiser(float *real, float *imag, int n, float beta)
{
//	float ino(float x);
	int i;
	// 	int odd = n % 2; 
	// 	float xind = (n-1)*(n-1);
	float temp;