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

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))+128

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

B=Abs(B(i-1,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,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,pDestColor)
            Next
        Next
        picDest.Image = destImg
    End Sub

运行效果如下：

由于.net平台下C#和vb.NET很相似，本文也可以为C#爱好者提供参考。

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