Institutional Repository | Satya Wacana Christian University: Embedding Pesan Rahasia Kedalam Gambar Menggunakan Metode Least Signnificant Bit

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Lampiran 1 Kode Program
Kode Program 1 Kode Program Login
Private Sub DoLogin()
Dim Sec As New User(Me.TxtUsername.Text, Me.TxtPassword.Text)
If Sec.Identity.IsAuthenticated = Nothing Then
_isLogIn = False
MsgBox("Username dan password tidak cocok",
MsgBoxStyle.Exclamation, "Failed to login")
Me.TxtPassword.Text = ""
Me.TxtPassword.Focus()
Else
_isLogIn = True
Me.Close()
End If
End Sub
Private Sub BtnLogIn_Click(ByVal sender As System.Object,
ByVal e As System.EventArgs) Handles BtnLogIn.Click
Try
DoLogin()
Catch ex As Exception

MsgBox(ex.Message, MsgBoxStyle.Critical, "Error")
End Try
End Sub
Private Sub BtnCancel_Click(ByVal sender As System.Object,
ByVal e As System.EventArgs) Handles BtnCancel.Click
Me.Close()
End Sub

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Kode Program 2 Kode Program Form Utama
Public Class Mainform
Private Sub OpenToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
OpenToolStripMenuItem.Click, AboutToolStripMenuItem.Click
Dim abt As New about
abt.ShowDialog()
End Sub
Private Sub EndcodeToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
EndcodeToolStripMenuItem.Click, EncodeButton.Click

Dim _enc As New Encode
_enc.ShowDialog()
End Sub
Private Sub ExitToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
ExitToolStripMenuItem.Click
Me.Close()
End Sub
Private Sub Button2_Click(ByVal sender As System.Object,
ByVal e As System.EventArgs) Handles Button2.Click
Dim Hd As New Decode
Hd.ShowDialog()
End Sub
Private Sub DecodeToolStripMenuItem_Click(ByVal sender As
System.Object, ByVal e As System.EventArgs) Handles
DecodeToolStripMenuItem.Click
Dim _hd As New Decode
_hd.ShowDialog()
End Sub
End Class

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Kode Program 3 Kode Program Hide
For Pc = 0 To gambar.Height - 1
For Pb = 0 To gambar.Width - 1
vR = gambar.GetPixel(Pb, Pc).R
vG = gambar.GetPixel(Pb, Pc).G
vB = gambar.GetPixel(Pb, Pc).B
xhuruf1 = Mid(T.Text, i, 1)
xhuruf2 = Mid(T.Text, i + 1, 1)
xhuruf3 = Mid(T.Text, i + 2, 1)
vR = Convect(toLSB(DesimalToBiner(vR), xhuruf1))
vG = Convect (toLSB(DesimalToBiner(vG), xhuruf2))
vB = Convect (toLSB(DesimalToBiner(vB), xhuruf3))
gambar.SetPixel(Pb, Pc, Color.FromArgb(vR, HG vB))
xpic = xpic + 1
If xpic > xpc Then Exit For
i = i + 3
Next

Kode Program 4 Kode Program Extract
For x = 0 To gambar.Height - 1
For y = 0 To gambar.Height - 1
vR = gambar.GetPixel(x, y).R
vG = gambar.GetPixel(x, y).G
vB = gambar.GetPixel(x, y).B
bit.Text
=
bit.Text
Microsoft.VisualBasic.Mid((DesimalToBiner(vR)), 8, 1) & _
Microsoft.VisualBasic.Mid((DesimalToBiner(v G)), 8, 1) & _
Microsoft.VisualBasic.Mid((DesimalToBiner(vB)), 8, 1)
xpic = xpic + 1
If xpic > xpc Then Exit For
bit.Refresh()
Next
Next

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