SLIDESHOW IN PLACE OF STATIC HEADER IMAGE

Is it possible to insert a slideshow in the SITE Header Image Area? I asked this question before and received the following answer...Go to => Appearance => Customize => Featured Post Slider => Slider Options => Enable and Insert the Post Id's you would like to show up on the slider. This seems to refer me to "Featured Posts"...what are those? The Customize option seems to be pointing to a Slider in a Post...as opposed to a slider in the SITE header area. Are these instructions really for placing a slider in the SITE header image area?