Converting RGB to CMYK using built-in conversion not working

Using Leadtools Ver 17 and your example in WhitePoint Property to convert an RGB File to CMYK. The output file is still an RGB file. I changed the example Visual Basic output file from .bmp to .tif as a .bmp file can only be an RGB file. I've attached the sample file and the result.
Here's the code I used:

Visual Basic (Declaration)

Public Property WhitePoint() As ConversionWhitePoint
Get

End Get
Set(ByVal value As ConversionWhitePoint)

End Set
End Property


Visual Basic Code


Public Sub WhitePointExampleExample()
' Initialize the RasterCodecs class
Dim codecs As RasterCodecs = New RasterCodecs

' StartUp the ColorConversion.
RasterColorConverterEngine.Startup()

' The input file name
' Dim inputFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "Image1.cmp"

' load the input image as Rgb.
'Dim inputFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "Image1.cmp"
Dim rgbImage As RasterImage = codecs.Load("d:\testrgb.jpg", 24, CodecsLoadByteOrder.Rgb, 1, 1)


' Image buffer array
Dim rgbBuffer(rgbImage.BytesPerLine * rgbImage.Height) As Byte

' get image buffer
For i As Integer = 0 To rgbImage.Height - 1
rgbImage.GetRow(i, rgbBuffer, (i * rgbImage.BytesPerLine), rgbImage.BytesPerLine)
Next
' Initialize the Cmyk buffer array
Dim cmykBuffer(CInt(rgbImage.Height * rgbImage.Width * 4)) As Byte

' Initialize a new Converter object
Dim converter As New RasterColorConverterEngine

' Initialize a new ConversionParameters new class object.
Dim convParams As ConversionParameters = New ConversionParameters

' Initialize the WhitePoint property class.
Dim whitePoint As ConversionWhitePoint = ConversionWhitePoint.Empty

' Set the WhitePoint property.
whitePoint.WhitePoint = ConversionWhitePointType.D50

' Set the XWhite property.
whitePoint.XWhite = 0

' Set the YWhite property.
whitePoint.YWhite = 0
convParams.WhitePoint = whitePoint

' Set the Quantization property.
convParams.Quantization = 8

' Set the Method property.
convParams.Method = ConversionMethodFlags.UseBuiltIn

' Set the ActiveMethod property.
convParams.ActiveMethod = ConversionMethodFlags.UseBuiltIn

' Set GcrLevel property.
Dim cmykParameters As New ConversionCmykParameters()
cmykParameters.GcrLevel = 150
convParams.CmykParameters = cmykParameters

Try
' Start the ColorConversion.
converter.Start(ConversionColorFormat.Rgb, ConversionColorFormat.Cmyk, convParams)

' Convert Rgb to CMYK.
converter.Convert(rgbBuffer, 0, cmykBuffer, 0, rgbImage.Width, rgbImage.Height, CInt(rgbImage.BytesPerLine - (rgbImage.Width * (rgbImage.BitsPerPixel / 8))), 0)

' Stop the ColorConversion.
converter.Stop()

' Initialize an image to hold the converted buffer.
Dim cmykImage As RasterImage = New RasterImage(RasterMemoryFlags.Conventional, rgbImage.Width, rgbImage.Height, 24, RasterByteOrder.Bgr, RasterViewPerspective.TopLeft, Nothing, IntPtr.Zero, 0)

' Start the color conversion
converter.Start(ConversionColorFormat.Cmyk, ConversionColorFormat.Bgr, convParams)

' convert the image buffer
converter.ConvertToImage(cmykBuffer, 0, cmykImage, rgbImage.Width, rgbImage.Height, 0, CInt(rgbImage.BytesPerLine - (rgbImage.Width * (rgbImage.BitsPerPixel / 8))))

' stop the conversion
converter.Stop()

' the output File Name.
' Dim outputFileName As String = LeadtoolsExamples.Common.ImagesPath.Path + "ResultImage.bmp"

' Save the result image.
codecs.Save(cmykImage, "d:\testcmykoutput.tif", RasterImageFormat.Tif, 24)

' dispose the used images
rgbImage.Dispose()
cmykImage.Dispose()
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
' Shutdown the ColorConversion.
RasterColorConverterEngine.Shutdown()
End Sub

The ConvertToImage() method does not maintain the CMYK data. It will create a LEAD RGB bitmap from the CMYK buffers.

If the buffers contain the correct CMYK data you need, the best way to keep that data and save it to TIFF would be:
1. Create 4 bitmaps, one from each CMYK plane. Each bitmap will be 8-bit grayscale.
2. Create one RasterImage object that has 4 pages. The pages should be the C, M, Y and K grayscale images in that order.
3. Save the resulting 4-plane RasterImage to a CMYK tiff format such as TifCmyk or TifLzwCmyk using the  RasterCodecs.SaveCmykPlanes() method.

Please read the help topic "Handling CMYK Files as Separate Images" in our .NET help file.

I understand. I'll review the help topic.