Converting color images to grayscale

Q:  How can I convert a color image to grayscale?

A:  Converting a color image to grayscale can be done by Antialising (ConvColorDIBtoGrayScale implemented in BIDIB.OCX) or Desaturating (Desaturate implemented in BIIMAGE.OCX). Antialising can only be applied to a 8 bit per pixel color images. If a 24 bit per pixel color image is to be converted to grayscale, first use a dithering function and after that use antialising. Desaturating methods can be applied on both 8 bit per pixel and 24 bit per pixel images.

Code example:

       Dim hSourceDib As Long

       Dim hResDib As Long

       Dim BIImageObj As Object

       ‘        Load the input image

       …

                Set BIImageObj = CreateObject("BIIMAGE.BIImageCtrl.1")

                hResDib = BIImageObj.Desaturate(hSourceDib, DispBoth, hWnd)

                Set BIImageObj = Nothing

       ‘        Further processing