GrayscalePreview  558 Magick++/lib/Magick++/Include.h   using MagickCore::GrayscalePreview;
GrayscalePreview 2407 magick/effect.c       case GrayscalePreview:
GrayscalePreview 1435 magick/option.c     { "Grayscale", GrayscalePreview, UndefinedOptionFlag, MagickFalse },