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

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38 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()

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39 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) Handle s 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

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40 Kode Program 3

Kode Program Hide

Kode Program 4 Kode Program Extract

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

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()