IsGrayPixel      1343 coders/gif.c             if (IsGrayPixel(image->colormap+i) == MagickFalse)
IsGrayPixel      2014 coders/pnm.c                       if (IsGrayPixel(p) == MagickFalse)
IsGrayPixel      2034 coders/pnm.c                       if (IsGrayPixel(p) == MagickFalse)
IsGrayPixel      2052 coders/pnm.c                   if (IsGrayPixel(p) == MagickFalse)
IsGrayPixel      1246 magick/colorspace.c       if (IsGrayPixel(p) == MagickFalse)