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How to draw Line Profile on invisible image?

Hi guys,

I  create an invisible image and I want to draw Line Profile on it .
But it pop up an error message about
'Unable to cast COM object of type 'MediaCy.IQL.Engine.McImageClass' to interface type 'MediaCy.IQL.Application.IMcDocument'.

Dim im As McImage = ThisApplication.ActiveImage
Dim invisible_im As McImage = im.Duplicate(mcImageCreateFlags.mcicfNotVisible) 'Create invisible image

With Measure.LineProfile.ProfileCommands.Add(Nothing)
     .ProfileType = LineProfile.ProfileTypes.Line
     .Points = New System.Collections.Generic.List(Of System.Drawing.PointF)
     .Points.Add(New System.Drawing.PointF(1689, 1116))
     .Points.Add(New System.Drawing.PointF(1952, 1116))
     .Angle = 0R
     .CreateEngine = true
     .Run(invisible_im) 'Draw Line Profile on invisible image
End With

Can I draw Line Profile  on invisible image?

Please help me to solve this annoying problem, thanks!


  • Hi Tony,

    Line Profile commands works with IMcDocument (visible image or image set) and will not work with invisible image. As workaround you can create McLines instance attached to invisible image (Ex: Dim lines As McLines = McApplication.ThisApplication.CreateOperator("McLines", MyInvisibleImage, "MYLines")) and use lines.Profiles to analyze edges.

  • Hi Tony,

    With small modifications in the macro you can create invisible document and use it with the line profile commands:
        Public Function InvisibleDocument() As SimpleScript
            InvisibleDocument = New SimpleScript
            Dim im1, doc1, win1
            With Automate.ScriptingCommands.CodeCommand(InvisibleDocument)
                If .Run() Then
                    ' User Code Here
                    im1 = .Application.ActiveImage.Duplicate(mcImageCreateFlags.mcicfNotVisible) 'create invisible image
                    doc1 = .Application.Documents.Add(im1) 'create invisible document
                End If
            End With
            With Measure.LineProfile.ProfileCommands.RemoveAll(InvisibleDocument)
                .CreateEngine = True 'force to create line profile engine for invisible document
            End With
            With Measure.LineProfile.ProfileCommands.Add(InvisibleDocument)
                .Text = "Add Profile"
                .ProfileType = LineProfile.ProfileTypes.Line
                .Points = New System.Collections.Generic.List(Of System.Drawing.PointF)
                .Points.Add(New System.Drawing.PointF(10F,10F))
                .Points.Add(New System.Drawing.PointF(100F,100F))
                .Angle = 0R
            End With
            With Application.DocumentCommands.Show(InvisibleDocument)
                .Run(doc1, win1)'show document
            End With
        End Function

    Key modifications:

    1) create invisible document from the invisible image
    doc1 = .Application.Documents.Add(im1) 'create invisible document

    2) force to create line profile engine (.CreateEngine = True should be set on the first line profile command)
    .CreateEngine = True
    Remember to close invisible document to free up the memory. 


  • Thanks Nikita, 

    This is of great help to me!
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