自動投票中驗證碼識別問題初探 現在很多網站投票、發帖都採取了驗證碼機制，如果驗證碼位置角度是固定的話，就可以採取先採樣產生字模，然後進行對比，最後得到對應的驗證碼。這種方法基本上可以不用除噪，而且識別率達到百分之百準確。下面是我寫的驗證碼識別代碼： Static Words As Byte
Dim i As Integer
Dim m As Integer
Dim n As Integer
Dim FNum As Integer
Dim ImgStr As String
Dim Kuan As Integer
Dim Gao As Integer
Dim lColor As Long
Dim MaNub As Integer
Dim DImgStr As String
Dim ZuiHouMa As String
Dim YZMa As Integer
Dim TopKong As Integer
Dim LeftKong As Integer
Dim RightKong As Integer
Dim CYL(0 To 15) As Integer '差異率
'驗證圖片寬度55，高度16,從第六個點（編號5）開始，到第50個點（編號49）結束,共五個字，5*9=45 上空4下空2
'驗證圖片寬度100 高度25 從26點開始，每字寬9，右空2，上空5，高13
MaNub = 5 '一幅圖裡有幾個碼
Kuan = 9
Gao = 13
TopKong = 5
LeftKong = 26
RightKong = 2
WordX = (Me.Left + Picture1.Left) / Screen.TwipsPerPixelX + LeftKong
WordY = (Me.Top + Picture1.Top) / Screen.TwipsPerPixelY + TopKong
'MsgBox WordX & WordY
'ls = SetPixel(GetDC(0), WordX, WordY, vbGreen)
WordX = LeftKong
WordY = TopKong
ZuiHouMa = ""
For i = 0 To MaNub - 1
ImgStr = ""
For m = 0 To Gao - 1
For n = 0 To Kuan - 1
lColor = GetPixel(Picture1.hdc, WordX + n, WordY + m)
If GetRedValue(lColor) > 100 And GetGreenValue(lColor) < 100 And GetBlueValue(lColor) < 100 Then
ImgStr = ImgStr & "1"
Else
ImgStr = ImgStr & "0"
End If
Next n
Next m
YZMa = 9
CYL(YZMa) = 100
For m = 0 To 9
CYL(m) = 0
For n = 0 To Kuan * Gao - 1
If (Mid(FontDat(m), n + 1, 1) = "1") And (Mid(ImgStr, n + 1, 1) = "0") Then CYL(m) = CYL(m) + 1
If (Mid(FontDat(m), n + 1, 1) = "0") And (Mid(ImgStr, n + 1, 1) = "1") Then CYL(m) = CYL(m) + 1
Next n
If CYL(m) < CYL(YZMa) Then YZMa = m
Next m
ZuiHouMa = ZuiHouMa & Trim(Hex(YZMa))
WordX = WordX + Kuan + RightKong
Next i
Text1.Text = ZuiHouMa
程式運行介面如下：
註：介面借用了網上下載的一個程式。。但識別核心是我自己寫的。
DEMO程式如下：
http://my82163.51.net/readcode.rar
其它連結：
WebBrowser抓圖樣本——截取網頁上的驗證碼圖片
踏破鐵鞋無覓處：網頁下載圖片的代碼
自動更換IP的輔助投票工具
自動投票中驗證碼識別問題初探
關於自動投票工具軟體的實現
