TUGAS PENGGOLAHAN CITRA 3

DETEKSI TEPI

1. Pendeteksiaan gambar dengan operator Robert menggunakan visual basic

· Buka terlebih dahulu visual basic Anda masing-masing kemudian buatlah sebuah form yang berisikan tool-tool berikut ini :

TOOL	PROPERTIES
Picture1	Nama : pic1 Picture : beri foto kita Scale mode : pixel
Picture2	Nama : pic2 Scale mode : pixel
Label1	Caption : Original
Label2	Caption : Hasil
Button1	Caption : Deteksi tepi

· Sehingga tampilan formnya menjadi seperti gambar di bawah ini

· Tuliskan source code deklarasi dan prosedur pada menu general

Private Declare Function GetPixel Lib "gdi32" (ByVal hdc As Long, ByVal X As Long, ByVal Y As Long) As Long

Private Declare Function SetPixel Lib "gdi32" (ByVal hdc As Long, ByVal X As Long, ByVal Y As Long, ByVal crColor As Long) As Long

Dim R As Integer, G As Integer, B As Integer

Dim GradX As Long, GradY As Long, Grad As Long

Dim PixelValue As Long

Sub DecTORGB(ByVal Col As Long, R As Integer, G As Integer, B As Integer)

R = Col Mod 256

G = ((Col - R) Mod 65536) / 256

B = (Col - R - G) / 65536

If R < 0 Then R = 0: If R >= 255 Then R = 255

If G < 0 Then G = 0: If G >= 255 Then G = 255

If B < 0 Then B = 0: If B >= 255 Then B = 255

End Sub

· Berikut ini source code perintah operator Robert yang di tuliskan pada button1

Dim Op_X(-1 To 0, -1 To 0) As Integer, Op_Y(-1 To 0, -1 To 0) As Integer

Dim X As Integer, Y As Integer, I As Integer, J As Integer

Pic2.Cls

Grad = 0

Op_X(-1, -1) = 1: Op_X(0, -1) = 0

Op_X(-1, 0) = 0: Op_X(0, 0) = -1

Op_Y(-1, -1) = 0: Op_Y(0, -1) = -1

Op_Y(-1, 0) = 1: Op_Y(0, 0) = 0

For Y = 0 To Pic1.Height - 1

For X = 0 To Pic1.Width - 1

GradX = 0: GradY = 0: Grad = 0

If X = 0 Or Y = 0 Or X = Pic1.Width - 1 Or Y = Pic1.Height - 1 Then

Grad = 0

Else

For I = -1 To 0

For J = -1 To 0

PixelValue = GetPixel(Pic1.hdc, X + I, Y + J) //dapatkan pixel dari posisi x + i dan y + j

DecTORGB PixelValue, R, G, B //fungsi proses mendapatkan nilai RGB

Itensity = (R + G + B) / 3 //Itensitas / B & W

GradX = GradX + (Itensity * Op_X(I, J))

GradY = GradY + (Itensity * Op_Y(I, J))

Next J

Next I

Grad = Round(Sqr(Abs(GradX * GradX) + Abs(GradY * GradY)))

End If

If Grad <= 0 Then Grad = 0: If Grad >= 255 Then Grad = 255

SetPixel Pic2.hdc, X, Y, RGB(Grad, Grad, Grad)

Pic2.Refresh

Next X

Pic2.Refresh

Next Y

End Sub

· Contoh tampilan hasil deteksi gambar dengan operator Robert menggunakan visual basic

Contoh tampilan hasil deteksi gambar

SELAMAT MENCOBA

TUGAS PENGGOLAHAN CITRA 2

Brightness

Brightness adalah nilai kecerahan suatu pixel dalam suatu citra, yang menunjukan tingkat kecerahan dari hitam sampai putih. Tingkat kecerahan ini biasanya dinilai dari 0 (hitam) dan 255 (putih). Berikut ini saya postingkan langkah-langkah membuat aplikasi brightness dengan visual basic.

1. Buat form VB terlebih dahulu

2. Tambahkan components Microsoft windows common controls 6.0

3. Masukan tool-tool berikut ke dalam form

TOOL	PROPERTIES
Frame	Caption : Input
Frame	Caption : Output
Picturebox	Name : picInput Picture : foto kita sendiri
Picturebox	Name : picOutput
Slider	Name : sldLevel

tampilan form

4. Add modules dan tuliskan source code di bawah ini di dalamnya

Public Function getBrightness(cl As Long, level As Integer) As Long

//mencari nilai brightness di dalam gambar

' cl = Color wich will be brightened

' level = Brightness (between -255 and 255)

Dim r As Integer, g As Integer, b As Integer

//mencari nilai RGB

r = getRed(cl) + level

g = getGreen(cl) + level

b = getBlue(cl) + level

If r > 255 Then r = 255

If g > 255 Then g = 255

If b > 255 Then b = 255

If r < 0 Then r = 0

If g < 0 Then g = 0

If b < 0 Then b = 0

getBrightness = RGB(r, g, b)

End Function

Private Function getRed(color As Long)

//mencari nilai warna merah di dalam variable warna gambar

getRed = color And &HFF&

End Function

Private Function getGreen(color As Long)

//mencari nilai warna hijau di dalam variable warna gambar

getGreen = (color And &HFF00&) / &H100&

End Function

Private Function getBlue(color As Long)

//mencari nilai warna biru di dalam variable warna gambar

getBlue = (color And &HFF0000) / &H10000

End Function

5. Tuliskan deklarasi di bawah ini pada form1

Option Explicit

Private Declare Function SetPixel Lib "gdi32" ( _

ByVal hdc As Long, _

ByVal x As Long, _

ByVal y As Long, _

ByVal crColor As Long) As Long

Private Declare Function GetPixel Lib "gdi32" ( _

ByVal hdc As Long, _

ByVal x As Long, _

ByVal y As Long) As Long

Private m_blnAppExit As Boolean

6. Tuliskan source code perintah di bawah ini pada sldLevel

Private Sub sldLevel_Click()

m_blnAppExit = False

Dim x As Integer, y As Integer, intWidth As Integer, _

intHeight As Integer

//memperoleh panjang dan lebar gambar

intWidth = picInput.Width / Screen.TwipsPerPixelX - 3

intHeight = picInput.Height / Screen.TwipsPerPixelY - 2

picOutput.Picture = LoadPicture()

picOutput.Cls

//memperoleh setiap pixel di dalam gambar

For y = 0 To intHeight Step 1

For x = 0 To intWidth Step 1

'Get BrightValue for this pixel and (re)paint it

SetPixel _

picOutput.hdc, _

x, _

y, _

modules.getBrightness( _

GetPixel(picInput.hdc, x, y), _

sldLevel.Value)

Next

picOutput.Refresh

Next

//refresh picOutput

picOutput.Refresh

DoEvents

m_blnAppExit = True

End Sub

7. Dan hasilnya……

8. Hasilnya…………………

nilai brightness bertambah berdasarkan penambahan/pengurangan nilai level kecerahan pada setiap pixel.

SELAMAT MENCOBA

TUGAS PENGGOLAHAN CITRA 1

TUGAS MENAMPILKAN GAMBAR DAN HISTOGRAM

Private Sub Form_Load()

Drive1.Drive = "d:\"

End Sub

Private Sub Dir1_Change()

File1.Path = Dir1.Path

End Sub

Private Sub Drive1_Change()

Dir1.Path = Drive1.Drive

End Sub

Private Sub File1_Click()

On Error GoTo Pesan

Picture1.Picture = LoadPicture(Dir1.Path & "\" & File1.FileName)

Pesan:

If Err.Number = 481 Then

MsgBox "Gambar tidak bisa tampil", vbOKOnly, "PERINGATAN"

End If

End Sub

Private Sub Command1_Click()

Dim hr(256) As Integer, hg(256) As Integer, hb(256) As Integer

Dim ht2 As Long

Dim xp As Integer, i As Integer, j As Integer

Dim r As Integer, g As Integer, b As Integer

Dim warna As Long, X As Long, a As Long

Picture2.Cls

Picture3.Cls

Picture4.Cls

Me.MousePointer = vbHourglass

For i = 1 To 256

hr(i) = 0

hg(i) = 0

hb(i) = 0

Next

For i = 1 To Picture1.Width Step 15

For j = 1 To Picture1.Height Step 15

warna = Picture1.Point(i, j)

r = warna And RGB(255, 0, 0)

g = Int((warna And RGB(0, 255, 0)) / 256)

b = Int(Int((warna And RGB(0, 0, 255)) / 256) / 256)

If r > 255 Then r = 255

If g > 255 Then g = 255

If b > 255 Then b = 255

hr(r) = hr(r) + 1

hg(g) = hg(g) + 1

hb(b) = hb(b) + 1

Next j

Next i

ht2 = Picture2.Height

For i = 1 To 256

xp = 15 * (i - 1) + 1

Picture2.Line (xp, ht2 - hr(i))-(xp, ht2), RGB(255, 0, 0)

Picture3.Line (xp, ht2 - hg(i))-(xp, ht2), RGB(0, 255, 0)

Picture4.Line (xp, ht2 - hb(i))-(xp, ht2), RGB(0, 0, 255)

Next i

Me.MousePointer = vbNormal

End Sub

Private Sub Command2_Click()

Unload Me

End Sub