Desktop Functions:

   Smart Device Functions:

Show Recent Changes
Subscribe (RSS)
Misc. Pages
Helpful Tools
Suggested Reading
Website TODO List
Support Forum
Download Visual Studio Add-In

Terms of Use
Privacy Policy
MoveMemory (kernel32)
The MoveMemory function moves a block of memory from one location to another.

C# Signature:

[DllImport("Kernel32.dll", EntryPoint="RtlMoveMemory", SetLastError=false)]
static extern void MoveMemory(IntPtr dest, IntPtr src, int size);

VB Signature:

Declare Auto Sub MoveMemory Lib "Kernel32.dll" _
    Alias "RtlMoveMemory" (ByVal dest As IntPtr, ByVal src As IntPtr, ByVal size As Integer)

VBA Signature:

Private Declare PtrSafe Function MoveMemory Lib "KERNEL32.dll" _
    Alias "RtlMoveMemory" (ByVal dest As LongPtr, ByVal src As LongPtr, ByVal size As Integer)

User-Defined Types:


Alternative Managed API:

Use Marshal.Copy() twice to move from the unmanaged heap into a managed array and back out. Not ideal.

Tips & Tricks:

Please add some!

Sample Code:

<DllImport("kernel32.dll", EntryPoint:="RtlMoveMemory", SetLastError:=True, CharSet:=CharSet.Auto, ExactSpelling:=True, CallingConvention:=CallingConvention.StdCall)> _

Public Shared Sub CopyArrayTo(<[In](), MarshalAs(UnmanagedType.I4)> ByVal hpvDest As Int32, <[In](), Out()> ByVal hpvSource() As Byte, ByVal cbCopy As Integer)

End Sub

Public Function ConvertRBGTo1bpp(ByVal pSrcImg As Image) As Bitmap

  Dim nColors As Integer = 2
  Select Case nColors
    Case nColors > 256
      nColors = 256
    Case nColors < 2
      nColors = 2
  End Select
  Dim Width As Integer = pSrcImg.Width
  Dim Height As Integer = pSrcImg.Height
  Dim bitmap As Bitmap = New Bitmap(Width, Height, PixelFormat.Format1bppIndexed)
  Dim BmpCopy As Bitmap = New Bitmap(Width, Height, PixelFormat.Format32bppArgb)
  Dim g As Graphics
  g = Graphics.FromImage(BmpCopy)
  g.PageUnit = GraphicsUnit.Pixel
  g.DrawImage(pSrcImg, 0, 0, Width, Height)
  Dim bitmapData As BitmapData
  Dim rect As Rectangle = New Rectangle(0, 0, Width, Height)
  bitmapData = bitmap.LockBits(rect, ImageLockMode.WriteOnly, PixelFormat.Format1bppIndexed)
  Dim pixels As IntPtr = bitmapData.Scan0
  Dim bits As Byte()
  Dim pBits As Int32
  If (bitmapData.Stride > 0) Then
    pBits = pixels.ToInt32()
    pBits = pixels.ToInt32() + bitmapData.Stride * (Height - 1)
  End If
  Dim stride As Integer = Math.Abs(bitmapData.Stride)
  ReDim bits(Height * stride) ' Allocate the working buffer.
  Dim row As Integer
  Dim col As Integer
  Dim bmask As Integer
  For row = 0 To Height - 1
    For col = 0 To Width - 1
      Dim pixel As Color ' The source pixel.
      Dim i8BppPixel As Integer = (row * stride) + Int(col / 8)
      bmask = &H80 / (2 ^ (col Mod 8))
      pixel = BmpCopy.GetPixel(col, row)
      Dim luminance As Double = (pixel.R * 0.299) + (pixel.G * 0.587) + (pixel.B * 0.114)
      Dim colorIndex As Double = Math.Round((luminance * (nColors - 1) / 255))
      If colorIndex = 0 Then
    bits(i8BppPixel) = bits(i8BppPixel) Or (bmask And 0) 'Black
    bits(i8BppPixel) = bits(i8BppPixel) Or (bmask Or 0) 'White
      End If
    Next col
  Next row
  CopyArrayTo(pBits, bits, Height * stride)
  Return bitmap

End Function

MoveMemory on MSDN

Please edit this page!

Do you have...

  • helpful tips or sample code to share for using this API in managed code?
  • corrections to the existing content?
  • variations of the signature you want to share?
  • additional languages you want to include?

Select "Edit This Page" on the right hand toolbar and edit it! Or add new pages containing supporting types needed for this API (structures, delegates, and more).

Access directly from VS:
Terms of Use
Edit This Page
Find References
Show Printable Version