frmfft2.frm

脑波FFT分析程序,是分析周波数并画图的程序,用在脑波分析软件中

VERSION 5.00
Begin VB.Form frmFFT 
   BackColor       =   &H8000000B&
   Caption         =   "FFT"
   ClientHeight    =   4680
   ClientLeft      =   60
   ClientTop       =   345
   ClientWidth     =   8880
   LinkTopic       =   "Form1"
   ScaleHeight     =   4680
   ScaleWidth      =   8880
   StartUpPosition =   3  'Windows Default
   Begin VB.PictureBox Picture2 
      Height          =   3015
      Left            =   1200
      ScaleHeight     =   2955
      ScaleWidth      =   7155
      TabIndex        =   11
      Top             =   480
      Width           =   7215
   End
   Begin VB.PictureBox Picture1 
      AutoRedraw      =   -1  'True
      BackColor       =   &H80000009&
      Height          =   1365
      Left            =   480
      ScaleHeight     =   1305
      ScaleWidth      =   3795
      TabIndex        =   10
      Top             =   360
      Width           =   3855
   End
   Begin VB.CommandButton Command1 
      Caption         =   "Command1"
      Height          =   375
      Left            =   4680
      TabIndex        =   9
      Top             =   4080
      Width           =   1455
   End
   Begin VB.TextBox Text1 
      Height          =   375
      Left            =   2880
      TabIndex        =   8
      Text            =   "1"
      Top             =   4080
      Width           =   1455
   End
   Begin VB.PictureBox PicBox2 
      BackColor       =   &H80000009&
      Height          =   1575
      Index           =   1
      Left            =   4680
      ScaleHeight     =   1515
      ScaleWidth      =   3795
      TabIndex        =   5
      Top             =   2280
      Width           =   3855
   End
   Begin VB.PictureBox PicBox 
      BackColor       =   &H80000009&
      Height          =   1335
      Index           =   1
      Left            =   4680
      ScaleHeight     =   1275
      ScaleWidth      =   3795
      TabIndex        =   4
      Top             =   360
      Width           =   3855
   End
   Begin VB.PictureBox PicBox2 
      BackColor       =   &H80000009&
      Height          =   1575
      Index           =   0
      Left            =   480
      ScaleHeight     =   1515
      ScaleWidth      =   3795
      TabIndex        =   1
      Top             =   2280
      Width           =   3855
   End
   Begin VB.PictureBox PicBox 
      BackColor       =   &H80000009&
      Height          =   1335
      Index           =   0
      Left            =   480
      ScaleHeight     =   1275
      ScaleWidth      =   3795
      TabIndex        =   0
      Top             =   360
      Visible         =   0   'False
      Width           =   3855
   End
   Begin VB.Label Label2 
      Caption         =   "FFT(寢壥2)"
      Height          =   255
      Index           =   1
      Left            =   4800
      TabIndex        =   7
      Top             =   2040
      Width           =   975
   End
   Begin VB.Label Label1 
      Caption         =   "僨乕僞(2)"
      Height          =   255
      Index           =   1
      Left            =   4920
      TabIndex        =   6
      Top             =   120
      Width           =   735
   End
   Begin VB.Label Label2 
      Caption         =   "FFT(寢壥1)"
      Height          =   255
      Index           =   0
      Left            =   720
      TabIndex        =   3
      Top             =   1920
      Width           =   975
   End
   Begin VB.Label Label1 
      Caption         =   "僨乕僞(1)"
      Height          =   255
      Index           =   0
      Left            =   720
      TabIndex        =   2
      Top             =   120
      Width           =   735
   End
End
Attribute VB_Name = "frmFFT"
Attribute VB_GlobalNameSpace = False
Attribute VB_Creatable = False
Attribute VB_PredeclaredId = True
Attribute VB_Exposed = False
Option Explicit
Dim jj As Integer
Dim N As Integer
Dim x() As Double, y() As Double

Private Sub Command1_Click()



PicBox2(0).Cls
PicBox2(1).Cls

Visible = True: AutoRedraw = True
Width = 9000: Height = 5000
Dim pi As Double
pi = 4 * Atn(1)

N = 256
ReDim x(N) As Double, y(N) As Double
   frmSinWave2 x(), y(), N
   fftMain Me.PicBox(0), Me.PicBox2(0), x(), y(), N, 0
   
   frmStep x(), y(), N
   fftMain Me.PicBox(1), Me.PicBox2(1), x(), y(), N, 0

End Sub

Private Sub Form_Load()
Visible = True: AutoRedraw = True
Width = 9000: Height = 5000
Dim pi As Double
pi = 4 * Atn(1)

N = 256
ReDim x(N) As Double, y(N) As Double
   frmSinWave2 x(), y(), N
   fftMain Me.PicBox(0), Me.PicBox2(0), x(), y(), N, 0
   
   frmStep x(), y(), N
   fftMain Me.PicBox(1), Me.PicBox2(1), x(), y(), N, 0
   
   
Picture1.DrawWidth = 1 '定义画出点的大小
Picture1.Scale (0, 200)-(9000, -200) '定义坐标
Dim sA As String   '声明变量
Open "a.txt" For Input As #1 '打开文件
For jj = 0 To 9000 Step 1
Line Input #1, sA  '读出一行数据
Picture1.PSet (jj, Val(sA))
Next jj
Close #1 '关闭文件


End Sub
 
 Private Sub frmStep(x() As Double, y() As Double, N As Integer)
  Dim i As Integer
  For i = 1 To N
    If i <= N / 2 Then
      x(i) = -1
    Else
      x(i) = 1
    End If
    y(i) = 0
  Next i
 End Sub

Private Sub frmSinWave1(x() As Double, y() As Double, N As Integer)
Dim i As Integer, dt1 As Double, dt2 As Double, dt3 As Double
Dim pi As Double
    pi = 4 * Atn(1)
    dt1 = 2 * pi * 4 / N
    dt2 = 2 * pi * 16 / N
    dt3 = 2 * pi * 32 / N
    
    For i = 1 To N
       x(i) = Sin(dt1 * (i - 1)) + 0.5 * Sin(dt2 * (i - 1) + pi / 4) + 0.25 * Sin(dt3 * (i - 1))
       y(i) = 0
    Next i
    
End Sub

Private Sub frmSinWave2(x() As Double, y() As Double, N As Integer)
Dim i As Integer, dt1 As Double, dt2 As Double
Dim pi As Double
    pi = 4 * Atn(1)
    dt1 = 2 * pi * 4.4 / N
   ' dt2 = 2 * pi * 16 / N
     
    For i = 1 To N
       x(i) = Sin(dt1 * (i - 1)) ' + 0.5 * Sin(dt2 * (i - 1) + pi / 4)
       y(i) = 0
    Next i
    
End Sub



Private Sub Text1_KeyPress(KeyAscii As Integer)
      If (KeyAscii < Asc("0") Or KeyAscii > Asc("9")) And KeyAscii >= Asc(" ") Then
          KeyAscii = 0
      End If
End Sub