2012_计算机数字图像处理方法_ppt_1

计算机数字图像处理方法杨为民2012第一章VB图像显示•VB图像显示控件——PictureBox•主要属性：–ScaleMode 3 —Pixel 象元–AutoRedraw True 自动更新–Top、Left 、Width 、Height–坐标换算Screen.TwipsPerPixelX–Screen.TwipsPerPixelY–例子：Pic_Box.Width=320* Screen.TwipsPerPixelXPictureBox主要方法•PictureBox主要方法：–画一个“点”–格式Pset(x，y)，Color–颜色长整数–生成颜色RGB(R，G，B)–例子：Pic_Box.Pset（150,100），RGB（255，0，255）–画一条“线”–格式Line (x1，y1) -(x2，y2) ，Color，[B][F]–颜色长整数–充填模式 B 画框 F 填心–例子：Pic_Box.Line（20，50）-（60，10），C，BFPictureBox初始化•PictureBox初始化•Pic_Disp.AutoRedraw= True•Pic_Disp.ScaleMode= 3••Pic_Disp.Left= 60 * Screen.TwipsPerPixelX •Pic_Disp.Top= 160 * Screen.TwipsPerPixelY •Pic_Disp.Width= 401 * Screen.TwipsPerPixelX •Pic_Disp.Height= 401 * Screen.TwipsPerPixelYPictureBox显示过程•PictureBox显示过程•Pic_Disp.Cls••For i = 0 To 400•For j = 0 To 400•R = Pic_R(i, j)•G = Pic_G(i, j)• B = Pic_B(i, j)••Pic_Disp.PSet(j, i), RGB(R, G, B)••Next j•Next I•Pic_Disp.Refresh数字图像的计算机表示•两维数组–数字图像在计算机中用两维数组表示–行—Y方向–列—X方向–R，G，B 三个数组表示三个颜色–每个象元的三个颜色分别对应数组的元素•例子：–x=100–Y=200–R_Data(y，x)=255–G_Data(y，x)=0–B_Data(y，x)=255数字图像实验一数字万花筒第二章BMP图像显示第一节装载图像•装载图像–将图像装载到Picture Box 控件中–从Picture Box 控件中读取数据到数组中–将图像数组中的图像处理后进行显示（1）选择图像文件•CDlg_File.InitDir= App.Path•CDlg_File.FileName= ""•CDlg_File.Filter= "BMP图像(*.bmp)|*.bmp"•CDlg_File.ShowOpen•str1 = CDlg_File.FileName•If str1 = "" Then•Exit Sub•End If（2）在输入图像框中装载图像•Pic_Inp.Cls•Pic_Inp.Picture= LoadPicture(str1)•Pic_Inp.Refresh••Pic_Rows= 200•Pic_Cols= 320••ReDim Pic_R(0 To Pic_Rows-1, 0 To Pic_Cols-1)•ReDim Pic_G(0 To Pic_Rows-1, 0 To Pic_Cols-1)•ReDim Pic_B(0 To Pic_Rows-1, 0 To Pic_Cols-1)•注：很难得到图像的大小（3）读图像数据到数组中•For i = 0 To Pic_Rows-1•For j = 0 To Pic_Cols-1•n = Pic_Inp.Point(j, i)•Call Color_RGB(n, R, G, B)•Pic_R(i, j) = R•Pic_G(i, j) = G•Pic_B(i, j) = B•Next j•Next i（4）Windows 颜色到RGB的转换•Public Sub Color_RGB(ByVal Color As Long, R As Long,G As Long, B As Long)•Dim n As Long••n = Color And &HFFFFFF ‘低三个字节•R = n And &HFF ‘最低字节•n = Int(n/ 256)•G = n And &HFF•n = Int(n/ 256)• B = n And &HFF•End Sub（5）装载图像的优缺点•支持多种格式–LoadPicture() 函数支持BMP和JPG等格式•使用简单–一个函数•缺点–不知道原始图像的信息–难以进行进一步的处理第二节打开24位彩色图像•打开图像–从图像文件中直接读取数据到数组中–将图像数组中的图像进行显示（2）BMP图像头格式•偏移名称类型内容•0BMPID As Integer“BM”图像标识&H4D42• 2 BFSize As Long文件尺寸•6BFresever1 As Integer保留•8BFresever2 As Integer保留•10ImageBegin As Long图像数据开始位置•14 HeaderSize As Long头长度=40•18 Width As Long图像的“列数”•22 Height As Long图像的“行数”•26Planes As Integer图像的平面数=1•28Bits As Integer每个象元的位数{1，4，8，24}•30Compress As Long是否采用压缩=0•34ImageSize As Long图像数据的长度•38XPixelPerMeter As Long图像的水平分辨率（象元/米）•42YPixelPerMeter As Long图像的垂直分辨率（象元/米）•46ColorUsed As Long实际使用彩色数=0 —>256•50ColorImport As Long重要彩色数=0 —>256•54LUT(0 To 255) As RGBY_Def彩色查找表（当Bits=8时）（3）图像头定义—VB形式•Public Type BMPHDR_Def•BMPID As Integer•BFSize As Long•BFresever1 As Integer•BFresever2 As Integer•ImageBegin As Long•HeaderSize As Long•Width As Long•Height As Long•…………………•ColorUsed As Long•ColorImport As Long•LUT(0 To 255) As RGBY_Def•End Type公共数据定义•Dim Pic_R() As Integer•Dim Pic_G() As Integer•Dim Pic_B() As Integer•Dim Pic_Rows As Long, Pic_Cols As Long •Dim FileNo As Integer, Fptr As Long•Dim BMP_HDR As BMPHDR_Def•Dim RowL As Long•Dim BGR_Data(0 To 2) As Byte, B_Data As Byte•FileNo= FreeFile(1)•Open str1 For Binary As #FileNo•Fptr= 1•Get #FileNo, Fptr, BMP_HDR••Select Case BMP_HDR.Bits‘颜色位数••Case 24•'----------------------------•Pic_Rows= BMP_HDR.Height•Pic_Cols= BMP_HDR.Width•RowL= Int((Pic_Cols* 3 + 3) / 4) * 4••ReDim Pic_R(0 To Pic_Rows-1, 0 To Pic_Cols-1)•ReDim Pic_G(0 To Pic_Rows-1, 0 To Pic_Cols-1)•ReDim Pic_B(0 To Pic_Rows-1, 0 To Pic_Cols-1)第三节打开8位彩色图像•打开图像–从图像文件中直接读取数据到数组中–将图像数组中的图像进行显示8位索引彩色BMP图像•偏移名称类型内容•28Bits As Integer= 8•10ImageBegin As Long= 1078 （54+1024）•18 Width As Long图像的“列数”•22 Height As Long图像的“行数”•每象元的字节数= 1• 2 BFSize As Long文件尺寸•34ImageSize As Long图像数据的长度•每一行图像数据的长度（字节数）为4 的倍数•46ColorUsed As Long实际使用彩色数=0 —>256•50ColorImport As Long重要彩色数=0 —>256•54LUT(0 To 255) As RGBY_Def彩色查找表（当Bits=8时）8位图像的参数•FileNo= FreeFile(1)•Open str1 For Binary As #FileNo•Fptr= 1•Get #FileNo, Fptr, BMP_HDR••Select Case BMP_HDR.Bits‘颜色位数•Case 8•'----------------------------•Pic_Rows= BMP_HDR.Height•Pic_Cols= BMP_HDR.Width•RowL= Int((Pic_Cols+ 3) / 4) * 4••ReDim Pic_R(0 To Pic_Rows-1, 0 To Pic_Cols-1)•ReDim Pic_G(0 To Pic_Rows-1, 0 To Pic_Cols-1)•ReDim Pic_B(0 To Pic_Rows-1, 0 To Pic_Cols-1)读取8位彩色数据•For i = 0 To Pic_Rows-1•For j = 0 To Pic_Cols-1•Fptr= (Pic_Rows-1 -i) * RowL+ j + 1 + BMP_HDR.ImageBegin •Get #FileNo, Fptr, B_Data••R = BMP_HDR.LUT(B_Data).R•G = BMP_HDR.LUT(B_Data).G• B = BMP_HDR.LUT(B_Data).B••Pic_B(i, j) = B•Pic_G(i, j) = G•Pic_R(i, j) = R••Next j•Next i•Close #FileNo第四节保存24位彩色图像•保存24位彩色图像–建立和保存图像头–建立一个象元的彩色数据–保存一个象元的彩色数据选择保存图像文件名CDlg_File.InitDir= App.PathCDlg_File.FileName= ""CDlg_File.Filter= "BMP图像(*.bmp)|*.bmp" CDlg_File.Flags= &H2CDlg_File.ShowSavestr1 = CDlg_File.FileNameIf str1 = "" ThenExit SubEnd If建立图像头中不变的部分BMP_HDR.BMPID = &H4D42 BMP_HDR.BFresever1 = 0BMP_HDR.BFresever2 = 0BMP_HDR.ColorImport= 0BMP_HDR.ColorUsed= 0BMP_press= 0BMP_HDR.HeaderSize= 40BMP_HDR.Planes= 1建立图像头中可变的部分BMP_HDR.Bits= 24BMP_HDR.ImageBegin= 54BMP_HDR.Width= Pic_ColsBMP_HDR.Height= Pic_RowsRowL= Int((Pic_Cols* 3 + 3) / 4) * 4BMP_HDR.ImageSize= Pic_Rows* RowL BMP_HDR.BFSize= BMP_HDR.ImageBegin + BMP_HDR.ImageSize建立/打开图像文件'----------------------------------------------------FileNo= FreeFile(1)Open str1 For Binary As #FileNoFptr= 1Put #FileNo, Fptr, BMP_HDR产生一个象元的数据For i = 0 To Pic_Rows-1For j = 0 To Pic_Cols-1' BGR_Data(0) = Pic_B(i, j)' BGR_Data(1) = Pic_G(i, j)' BGR_Data(2) = Pic_R(i, j)n = Pic_Out.Point(j, i)Call Color_RGB(n, R, G, B)BGR_Data(0) = BBGR_Data(1) = GBGR_Data(2) = R写一个象元的数据到图像文件中Fptr= (Pic_Rows-1 -i) * RowL+ j * 3 + 1 +BMP_HDR.ImageBeginPut #FileNo, Fptr, BGR_DataNext jNext iClose #FileNo。