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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/uruseibestPrivate Sub btnRed_Click(sender As Object, e As EventArgs) Handles btnRed.ClickDim destImg As New Bitmap(sourceImg.Width, sourceImg.Height)Dim sourceData As BitmapData = sourceImg.LockBits(New Rectangle(0, 0, sourceImg.Width, sourceImg.Height), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb)Dim destData As BitmapData = destImg.LockBits(New Rectangle(0, 0, sourceImg.Width, sourceImg.Height), ImageLockMode.WriteOnly, PixelFormat.Format24bppRgb)Dim pSource As IntPtr = sourceData.Scan0Dim allBytes As Integer = sourceData.Stride * sourceData.HeightDim rgbvalues() As ByteReDim rgbvalues(allBytes - 1)Marshal.Copy(pSource, rgbvalues, 0, allBytes)Dim pos As Integer = 0Dim R, G, B As IntegerFor j As Integer = 0 To sourceData.Height - 1For i As Integer = 0 To sourceData.Width - 1'B = rgbvalues(pos)'G = rgbvalues(pos + 1)R = rgbvalues(pos + 2)rgbvalues(pos) = Rrgbvalues(pos + 1) = Rrgbvalues(pos + 2) = Rpos = pos + 3Nextpos = pos + sourceData.Stride - sourceData.Width * 3NextDim pDest As IntPtr = destData.Scan0Marshal.Copy(rgbvalues, 0, pDest, allBytes)sourceImg.UnlockBits(sourceData)destImg.UnlockBits(destData)picDest.Image = destImgEnd Sub

绿色通道：

    '绿色通道'http://blog.csdn.net/uruseibestPrivate Sub btnGreen_Click(sender As Object, e As EventArgs) Handles btnGreen.ClickDim destImg As New Bitmap(sourceImg.Width, sourceImg.Height)Dim sourceData As BitmapData = sourceImg.LockBits(New Rectangle(0, 0, sourceImg.Width, sourceImg.Height), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb)Dim destData As BitmapData = destImg.LockBits(New Rectangle(0, 0, sourceImg.Width, sourceImg.Height), ImageLockMode.WriteOnly, PixelFormat.Format24bppRgb)Dim pSource As IntPtr = sourceData.Scan0Dim allBytes As Integer = sourceData.Stride * sourceData.HeightDim rgbvalues() As ByteReDim rgbvalues(allBytes - 1)Marshal.Copy(pSource, rgbvalues, 0, allBytes)Dim pos As Integer = 0Dim R, G, B As IntegerFor j As Integer = 0 To sourceData.Height - 1For i As Integer = 0 To sourceData.Width - 1'B = rgbvalues(pos)G = rgbvalues(pos + 1)'R = rgbvalues(pos + 2)rgbvalues(pos) = Grgbvalues(pos + 1) = Grgbvalues(pos + 2) = Gpos = pos + 3Nextpos = pos + sourceData.Stride - sourceData.Width * 3NextDim pDest As IntPtr = destData.Scan0Marshal.Copy(rgbvalues, 0, pDest, allBytes)sourceImg.UnlockBits(sourceData)destImg.UnlockBits(destData)picDest.Image = destImgEnd Sub

蓝色通道：

    '蓝色通道'http://blog.csdn.net/uruseibestPrivate Sub btnBlue_Click(sender As Object, e As EventArgs) Handles btnBlue.ClickDim destImg As New Bitmap(sourceImg.Width, sourceImg.Height)Dim sourceData As BitmapData = sourceImg.LockBits(New Rectangle(0, 0, sourceImg.Width, sourceImg.Height), ImageLockMode.ReadOnly, PixelFormat.Format24bppRgb)Dim destData As BitmapData = destImg.LockBits(New Rectangle(0, 0, sourceImg.Width, sourceImg.Height), ImageLockMode.WriteOnly, PixelFormat.Format24bppRgb)Dim pSource As IntPtr = sourceData.Scan0Dim allBytes As Integer = sourceData.Stride * sourceData.HeightDim rgbvalues() As ByteReDim rgbvalues(allBytes - 1)Marshal.Copy(pSource, rgbvalues, 0, allBytes)Dim pos As Integer = 0Dim R, G, B As IntegerFor j As Integer = 0 To sourceData.Height - 1For i As Integer = 0 To sourceData.Width - 1B = rgbvalues(pos)'G = rgbvalues(pos + 1)'R = rgbvalues(pos + 2)rgbvalues(pos) = Brgbvalues(pos + 1) = Brgbvalues(pos + 2) = Bpos = pos + 3Nextpos = pos + sourceData.Stride - sourceData.Width * 3NextDim pDest As IntPtr = destData.Scan0Marshal.Copy(rgbvalues, 0, pDest, allBytes)sourceImg.UnlockBits(sourceData)destImg.UnlockBits(destData)picDest.Image = destImgEnd Sub

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