Creating, Viewing, and Merging Color Separations (Visual Basic)

Take the following steps to add code that creates CMYK color separations, displays each of the color planes, merges the planes, and displays the result. The code increases the contrast of the K plane to demonstrate how you can manipulate the color separations.

1.	Start with the project that you created in Loading and Displaying an Image.
2.	$image\btncmd.gif$ Select the CommandButton control; then add the control to your main form. Put the control at the top of the form to keep it away from the image.
3.	In the Properties box, change the CommandButton control's Caption property to Do Separations.
4.	Add the LEAD RasterProcess Object Library to your project.
	On the Project pull-down menu, use the References option, and select the LEAD RasterProcess Object Library (14.5).
5.	Add the following code to the general declarations section of your project.

Public RasterProc As LEADRasterProcess

6.	Add the following code to the end of the Form_Load event handler.

'Create the RasterProcess Object
Set RasterProc = CreateObject("LEADRasterProcess.LEADRasterProcess. ")

7.	Add the following code to the CommandButton control's Click procedure. In online help, you can use the Edit pull-down menu to copy the block of code.

Sub Command6_Click ()
    Dim msg As String
    ' Count the button clicks and take the next step with each click
    Static ClickCount As Integer
    MousePointer = 11 ' hourglass
    'Turn off the automatic display rectangles.
    LEADRasterView1.AutoSetRects = False
    LEADRasterView1.Raster.RefBitmap = False
    Select Case ClickCount
    Case 0
        RasterProc.ColorSeparate LEADRasterView1.Raster, COLORSEP_CMYK
        'Just for fun, add contrast to the K plane
        LEADRasterView1.Raster.Bitmap = RasterProc.ColorPlanes(3) 'Copy the K plane
        RasterProc.Contrast LEADRasterView1.Raster, 300 'Increase the contrast
        RasterProc.ColorPlanes(3) = LEADRasterView1.Raster.Bitmap 'Update the K plane
        msg = "Separated. Keep clicking to see separations, then merge"
        MsgBox msg
    Case 1
        LEADRasterView1.Raster.Bitmap = RasterProc.ColorPlanes(0) 'Cyan
        LEADRasterView1.ForceRepaint
    Case 2
        LEADRasterView1.Raster.Bitmap = RasterProc.ColorPlanes(1) ' Magenta
        LEADRasterView1.ForceRepaint
    Case 3
        LEADRasterView1.Raster.Bitmap = RasterProc.ColorPlanes(2) ' Yellow
        LEADRasterView1.ForceRepaint
    Case 4
        LEADRasterView1.Raster.Bitmap = RasterProc.ColorPlanes(3) ' K
        LEADRasterView1.ForceRepaint
    Case 5
        RasterProc.ColorMerge LEADRasterView1.Raster, COLORSEP_CMYK
        LEADRasterView1.ForceRepaint
        RasterProc.ColorPlanes(0) = 0
        RasterProc.ColorPlanes(1) = 0
        RasterProc.ColorPlanes(2) = 0
        RasterProc.ColorPlanes(3) = 0
        msg = "Merged, with more contrast in the K plane"
        MsgBox msg
    Case Else
        ClickCount = -1
        msg = "Cycle is finished"
        MsgBox msg
    End Select
    ClickCount = ClickCount + 1
    MousePointer = 0 ' default
End Sub

8.	Run your program to test it. Notice that you can click the button several times to create the separations, view each of them, and merge them to recreate the original bitmap.