vb.net 教程 5-15 图像处理之内存处理1

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, 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.Scan0
Dim allBytes As Integer = sourceData.Stride * sourceData.Height
Dim rgbvalues() As Byte
ReDim rgbvalues(allBytes - 1)
Marshal.Copy(pSource, rgbvalues, 0, 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, 0, 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, 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.Scan0
Dim allBytes As Integer = sourceData.Stride * sourceData.Height
Dim rgbvalues() As Byte
ReDim rgbvalues(allBytes - 1)
Marshal.Copy(pSource, rgbvalues, 0, 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) = 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, 0, pDest, 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, 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.Scan0
Dim allBytes As Integer = sourceData.Stride * sourceData.Height
Dim rgbvalues() As Byte
ReDim rgbvalues(allBytes - 1)
Marshal.Copy(pSource, rgbvalues, 0, 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) = 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, 0, pDest, allBytes)

sourceImg.UnlockBits(sourceData)
destImg.UnlockBits(destData)

picDest.Image = destImg
End Sub

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