vb.net 教程 5-13 图像处理之像素处理 7- VB

订阅专栏
版权声明：本文为博主原创文章，转载请在显著位置标明本文出处以及作者网名，未经作者允许不得用于商业目的。

浮雕的算法：

下一行的红绿蓝颜色分量减去上一行的红绿蓝颜色分量，再加上128

如果小于0，那么等于0，如果大于255，那么等于255

R=R(i-1,j)-R(i,j)+128

G=G(i-1,j)-G(i,j)+128

B=B(i-1,j)-B(i,j)+128

主要代码如下：

'浮雕1
Private Sub btnEmboss_Click(sender As Object, e As EventArgs) Handles btnEmboss.Click
Dim pSourceColor1 As Color
Dim pSourceColor2 As Color
Dim pDestColor As Color

Dim destImg As New Bitmap(sourceImg.Width, sourceImg.Height)
Dim R, G, B As Integer
Dim R1, G1, B1 As Integer
Dim R2, G2, B2 As Integer

For i As Integer = 1 To sourceImg.Width - 1
For j As Integer = 0 To sourceImg.Height - 1
pSourceColor1 = sourceImg.GetPixel(i, j)
R1 = pSourceColor1.R
G1 = pSourceColor1.G
B1 = pSourceColor1.B

pSourceColor2 = sourceImg.GetPixel(i - 1, j)
R2 = pSourceColor2.R
G2 = pSourceColor2.G
B2 = pSourceColor2.B

R = R1 - R2 + 128
G = G1 - G2 + 128
B = B1 - B2 + 128

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

pDestColor = Color.FromArgb(R, G, B)
destImg.SetPixel(i, j, pDestColor)
Next
Next
picDest.Image = destImg
End Sub

运行效果如下：

我还看到了另外一个算法：

下一行的红绿蓝颜色分量减去上一行的红绿蓝颜色分量的绝对值，再加上128

如果小于0，那么等于0，如果大于255，那么等于255

R=Abs(R(i-1,j)-R(i,j))+128

G=Abs(G(i-1,j)-G(i,j))+128

B=Abs(B(i-1,j)-B(i,j))+128

主要代码如下：

'浮雕2
Private Sub btnEmboss2_Click(sender As Object, e As EventArgs) Handles btnEmboss2.Click
Dim pSourceColor1 As Color
Dim pSourceColor2 As Color
Dim pDestColor As Color

Dim destImg As New Bitmap(sourceImg.Width, sourceImg.Height)
Dim R, G, B As Integer
Dim R1, G1, B1 As Integer
Dim R2, G2, B2 As Integer

For i As Integer = 1 To sourceImg.Width - 1
For j As Integer = 0 To sourceImg.Height - 1
pSourceColor1 = sourceImg.GetPixel(i, j)
R1 = pSourceColor1.R
G1 = pSourceColor1.G
B1 = pSourceColor1.B

pSourceColor2 = sourceImg.GetPixel(i - 1, j)
R2 = pSourceColor2.R
G2 = pSourceColor2.G
B2 = pSourceColor2.B

R = Math.Min(Math.Abs(R1 - R2) + 128, 255)
G = Math.Min(Math.Abs(G1 - G2) + 128, 255)
B = Math.Min(Math.Abs(B1 - B2) + 128, 255)

pDestColor = Color.FromArgb(R, G, B)
destImg.SetPixel(i, j, pDestColor)
Next
Next
picDest.Image = destImg
End Sub
其中Math.Min(A,B)将返回A和B中较小的值。