- data
- Pointer to the unmanaged memory buffer containing the image new data.
- size
- Number of bytes in data.
Visual Basic (Usage) | Copy Code |
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Dim instance As RasterImage Dim data As IntPtr Dim size As Long instance.SetUserData(data, 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(Int32,Int32,Byte[]) methods to swap the R and G values for a particular pixel.
Visual Basic | Copy Code |
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Public Sub SetUserDataExample() Dim codecs As RasterCodecs = New RasterCodecs() Dim destFileName As String = Path.Combine(LEAD_VARS.ImagesDir, "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() End Sub Public NotInheritable Class LEAD_VARS Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images" End Class |
C# | Copy Code |
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public void SetUserDataExample() { RasterCodecs codecs = new RasterCodecs(); string destFileName = Path.Combine(LEAD_VARS.ImagesDir, "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(); } static class LEAD_VARS { public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images"; } |
SilverlightCSharp | Copy Code |
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public void SetUserDataExample(Stream destStream) { // Create an image with user defined data int width = 40; int height = 40; int bitsPerPixel = 24; // Create a user image RasterImage image = new RasterImage( RasterMemoryFlags.User, width, height, bitsPerPixel, RasterByteOrder.Bgr, RasterViewPerspective.TopLeft, null, null, 0); // Create a data buffer for the image data // and fill the pixel values (gradient) int size = width * height * 3; byte[] buffer = new byte[size]; 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--; } } // Set the user data of the image image.CopyData(buffer, buffer.Length); // Save the image RasterCodecs codecs = new RasterCodecs(); codecs.Save(image, destStream, RasterImageFormat.Bmp, 24); image.Dispose(); } |
SilverlightVB | Copy Code |
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Public Sub SetUserDataExample(ByVal destStream As Stream) ' Create an image with user defined data Dim width As Integer = 40 Dim height As Integer = 40 Dim bitsPerPixel As Integer = 24 ' Create a user image Dim image As RasterImage = New RasterImage(RasterMemoryFlags.User, width, height, bitsPerPixel, RasterByteOrder.Bgr, RasterViewPerspective.TopLeft, Nothing, Nothing, 0) ' Create a data buffer for the image data ' and fill the pixel values (gradient) Dim size As Integer = width * height * 3 Dim buffer As Byte() = New Byte(size - 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 += 1 End If Else If value = 0 Then inc = True value = 1 Else value -= 1 End If End If i += 3 Loop ' Set the user data of the image image.CopyData(buffer, buffer.Length) ' Save the image Dim codecs As RasterCodecs = New RasterCodecs() codecs.Save(image, destStream, RasterImageFormat.Bmp, 24) image.Dispose() End Sub |
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 RasterImage Constructor(RasterMemoryFlags,Int32,Int32,Int32,RasterByteOrder,RasterViewPerspective,RasterColor[],IntPtr,Int64) constructor passing RasterMemoryFlags.Userto the flags parameter.
Some image processing commands, such as Leadtools.ImageProcessing.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: Silverlight, Windows XP, Windows Server 2003 family, Windows Server 2008 family, Windows Vista, Windows 7, MAC OS/X (Intel Only), Windows Phone 7