Public Sub SetUserData( _
   ByVal data As IntPtr, _
   ByVal size As Long _
) 

Visual Basic (Usage)	Copy Code
Dim instance As RasterImage Dim data As IntPtr Dim size As Long   instance.SetUserData(data, size)

public void SetUserData( 
   IntPtr data,
   long size
)

public:
void SetUserData( 
   IntPtr data,
   long size
) 

Parameters

data

Pointer to the unmanaged memory buffer containing the image new data.

size

Number of bytes in data.

This example uses GetPixelData and SetPixelData methods to swap the R and G values for a particular pixel.

Visual Basic

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Public Sub SetUserDataExample()    RasterCodecs.Startup()    Dim codecs As RasterCodecs = New RasterCodecs()    Dim destFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "UserData.bmp"    ' Create an image with user defined data    Dim width As Integer = 40    Dim height As Integer = 40    Dim bitsPerPixel As Integer = 24    Dim size As Integer = width * height * 3    Dim data1 As IntPtr = Marshal.AllocHGlobal(size)    ' Load the image    Dim image As RasterImage = New RasterImage(RasterMemoryFlags.User, width, height, bitsPerPixel, RasterByteOrder.Bgr, RasterViewPerspective.TopLeft, Nothing, IntPtr.Zero, 0)    ' Get a pointer to the internal data and fill it with gray shades    Dim dataSize As Integer = CInt(image.DataSize)    Dim buffer As Byte() = New Byte(dataSize - 1) {}    Dim inc As Boolean = True    Dim value As Byte = 0    Dim i As Integer = 0    Do While i < buffer.Length       buffer(i + 0) = value       buffer(i + 1) = value       buffer(i + 2) = value       If inc Then          If value = 255 Then             inc = False             value = 254          Else             value = value + Convert.ToByte(1)          End If       Else          If value = 0 Then             inc = True             value = 1          Else             value = value - Convert.ToByte(1)          End If       End If       i += 3    Loop    ' Copy this buffer to the image data    Marshal.Copy(buffer, 0, data1, buffer.Length)    ' Set the user data    image.SetUserData(data1, dataSize)    ' Save the image    codecs.Save(image, destFileName, RasterImageFormat.Bmp, 24)    image.Dispose()    Marshal.FreeHGlobal(data1)    codecs.Dispose()    RasterCodecs.Shutdown() End Sub

C#

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public void SetUserDataExample()  {     RasterCodecs.Startup();     RasterCodecs codecs = new RasterCodecs();       string destFileName = LeadtoolsExamples.Common.ImagesPath.Path + "UserData.bmp";       // Create an image with user defined data     int width = 40;     int height = 40;     int bitsPerPixel = 24;     int size = width * height * 3;     IntPtr data1 = Marshal.AllocHGlobal(size);       // Load the image     RasterImage image = new RasterImage(        RasterMemoryFlags.User,        width,        height,        bitsPerPixel,        RasterByteOrder.Bgr,        RasterViewPerspective.TopLeft,        null,        IntPtr.Zero,        0);       // Get a pointer to the internal data and fill it with gray shades     long dataSize = image.DataSize;       byte[] buffer = new byte[dataSize];     bool inc = true;     byte value = 0;     for(int i = 0; i < buffer.Length; i += 3)     {        buffer[i + 0] = value;        buffer[i + 1] = value;        buffer[i + 2] = value;          if(inc)        {           if(value == 255)           {              inc = false;              value = 254;           }           else              value++;        }        else        {           if(value == 0)           {              inc = true;              value = 1;           }           else              value--;        }     }       // Copy this buffer to the image data     Marshal.Copy(buffer, 0, data1, buffer.Length);       // Set the user data     image.SetUserData(data1, dataSize);       // Save the image     codecs.Save(image, destFileName, RasterImageFormat.Bmp, 24);       image.Dispose();     Marshal.FreeHGlobal(data1);     codecs.Dispose();     RasterCodecs.Shutdown();  }

The data that you specify will not be copied, but instead will be referenced by the image until the image is disposed, or until you call this method again.

To set up a RasterImage object with unmanaged user data, call the _ctor constructor passing RasterMemoryFlags.Userto the flags parameter.

Some image processing commands, such as RotateCommand and ColorResolutionCommand, need to re-allocate the image data. If you create an image with RasterMemoryFlags.User, and pass it to these command, they will change the image to RasterMemoryFlags.Conventional and re-allocate memory. Your original memory will no longer be used.

You are responsible for managing the image data. Dispose will not free data.

Target Platforms: Microsoft .NET Framework 3.0, Windows XP, Windows Server 2003 family, Windows Server 2008 family

Reference