When saving 1-bit TIFF images, some viewers will display the image inverted.  This is caused because a 1-bit TIFF doesn't have a palette, but instead uses a TIFF tag to indicate whether bit 0 = white or black.

This problem can be resolved by correcting the palette so bit 0 = white.  Here is an example of how to correct the palette:

' Make sure a 1-bit palette is correct.
If ix.Image.ImageType = ixitPalette_1 Then
    Dim clr0 As ImgX_Color, clr1 As ImgX_Color
    Set clr0 = ix.Image.Palette.GetEntry(0)
    Set clr1 = ix.Image.Palette.GetEntry(1)
   
    ' clr0 should be white and clr1 should be black.
    If (clr0.Blue + clr0.Green + clr0.Red) < (clr1.Blue + clr1.Green + clr1.Red) Then
        ' The palette needs to be swapped and image data inverted.
        ix.Image.Palette.SetEntry 0, clr1
        ix.Image.Palette.SetEntry 1, clr0
        ix.Filters.Negative
    End If
End If