关于lockbits的使用，请看《
vb.net 教程 5-14 图像处理之内存处理基础1》系列
图像处理之内存处理对应图像处理之像素处理，
具体的算法请参考《
vb.net 教程 5-13 图像处理之像素处理1》，我把代码重新写到了使用LockBits。
红色通道：
'红色通道
'http://blog.csdn.net/uruseibest
Private Sub btnRed_Click(sender As Object,e As EventArgs) Handles btnRed.Click
Dim destImg As New Bitmap(sourceImg.Width,sourceImg.Height)
Dim sourceData As BitmapData = sourceImg.LockBits(New Rectangle(0,sourceImg.Width,sourceImg.Height),ImageLockMode.ReadOnly,PixelFormat.Format24bppRgb)
Dim destData As BitmapData = destImg.LockBits(New Rectangle(0,ImageLockMode.WriteOnly,PixelFormat.Format24bppRgb)
Dim pSource As IntPtr = sourceData.Scan0
Dim allBytes As Integer = sourceData.Stride * sourceData.Height
Dim rgbvalues() As Byte
ReDim rgbvalues(allBytes - 1)
Marshal.Copy(pSource,rgbvalues,allBytes)
Dim pos As Integer = 0
Dim R,G,B As Integer
For j As Integer = 0 To sourceData.Height - 1
For i As Integer = 0 To sourceData.Width - 1
'B = rgbvalues(pos)
'G = rgbvalues(pos + 1)
R = rgbvalues(pos + 2)
rgbvalues(pos) = R
rgbvalues(pos + 1) = R
rgbvalues(pos + 2) = R
pos = pos + 3
Next
pos = pos + sourceData.Stride - sourceData.Width * 3
Next
Dim pDest As IntPtr = destData.Scan0
Marshal.Copy(rgbvalues,pDest,allBytes)
sourceImg.UnlockBits(sourceData)
destImg.UnlockBits(destData)
picDest.Image = destImg
End Sub绿色通道：
'绿色通道
'http://blog.csdn.net/uruseibest
Private Sub btnGreen_Click(sender As Object,e As EventArgs) Handles btnGreen.Click
Dim destImg As New Bitmap(sourceImg.Width,B As Integer
For j As Integer = 0 To sourceData.Height - 1
For i As Integer = 0 To sourceData.Width - 1
'B = rgbvalues(pos)
G = rgbvalues(pos + 1)
'R = rgbvalues(pos + 2)
rgbvalues(pos) = G
rgbvalues(pos + 1) = G
rgbvalues(pos + 2) = G
pos = pos + 3
Next
pos = pos + sourceData.Stride - sourceData.Width * 3
Next
Dim pDest As IntPtr = destData.Scan0
Marshal.Copy(rgbvalues,allBytes)
sourceImg.UnlockBits(sourceData)
destImg.UnlockBits(destData)
picDest.Image = destImg
End Sub蓝色通道：
'蓝色通道
'http://blog.csdn.net/uruseibest
Private Sub btnBlue_Click(sender As Object,e As EventArgs) Handles btnBlue.Click
Dim destImg As New Bitmap(sourceImg.Width,B As Integer
For j As Integer = 0 To sourceData.Height - 1
For i As Integer = 0 To sourceData.Width - 1
B = rgbvalues(pos)
'G = rgbvalues(pos + 1)
'R = rgbvalues(pos + 2)
rgbvalues(pos) = B
rgbvalues(pos + 1) = B
rgbvalues(pos + 2) = B
pos = pos + 3
Next
pos = pos + sourceData.Stride - sourceData.Width * 3
Next
Dim pDest As IntPtr = destData.Scan0
Marshal.Copy(rgbvalues,allBytes)
sourceImg.UnlockBits(sourceData)
destImg.UnlockBits(destData)
picDest.Image = destImg
End Sub
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原文链接：https://www.f2er.com/vb/256693.html