ChannelThresholdOptions_t  878 magick/effect.c   const ChannelThresholdOptions_t
ChannelThresholdOptions_t  879 magick/effect.c     *options = (const ChannelThresholdOptions_t *) immutable_data;
ChannelThresholdOptions_t  919 magick/effect.c   ChannelThresholdOptions_t