Clarrification re: Element::e_group_begin and Element::e_group_end

I was hoping you could help me understand the group begin and group end tags. Do they correspond to a particular token in the PDF spec? I’m trying to figure out if I can ignore them for my purposes or not, can I skip processing them, or do they have some special sub elements I need to descend into to traverse the full pdf content? I’m particularly interested in extracting text and font information.


Element::e_group_begin is same as ‘q’ operator (i.e. graphics state save)

Element::e_group_end is same as ‘Q’ operator (i.e. graphics state pop)