如何用vb將圖片二值化？

Dim R As Byte

Dim G As Byte

Dim B As Byte

Dim aaa As Long

Dim bbb As Byte

Dim i As Integer

Dim j As Integer

Private Sub Command1_Click()

For i = 1 To Picture1.ScaleHeight Step 15

For j = 1 To Picture1.ScaleWidth Step 15

aaa = Picture1.Point(j, i)

R = (aaa Mod 256) '取得紅色值

G = (aaa Mod 65536) \ 256 '取得綠色值

B = (aaa Mod 16777216) \ 65536 '取得藍色值

bbb = R / 3 + G / 3 + B / 3 '取得灰度值

If bbb >= 171 Then '這裏bbb可作適當改變以獲得最佳2值化效果

Picture2.PSet (j, i), RGB(255, 255, 255)

Else

Picture2.PSet (j, i), RGB(0, 0, 0)

End If

Next j

Next i

End Sub