diff --git a/MagickCore/gem-private.h b/MagickCore/gem-private.h
index 6c236bb..fce2351 100644
--- a/MagickCore/gem-private.h
+++ b/MagickCore/gem-private.h
@@ -32,10 +32,14 @@
GetOptimalKernelWidth2D(const double,const double);
extern MagickPrivate void
+ ConvertHCLToRGB(const double,const double,const double,double *,double *,
+ double *),
ConvertHSBToRGB(const double,const double,const double,double *,double *,
double *),
ConvertHWBToRGB(const double,const double,const double,double *,double *,
double *),
+ ConvertRGBToHCL(const double,const double,const double,double *,double *,
+ double *),
ConvertRGBToHSB(const double,const double,const double,double *,double *,
double *),
ConvertRGBToHWB(const double,const double,const double,double *,double *,