What are the requisites for Scopus to index the proceedings of a conference? I have seen that some conferences in the CS field are indexed by Scopus, I mean their conference proceedings. I have found some information about the requisites a journal should have to be indexed in Scopus, but I did not find any information about conference proceedings. Are those requirements the same?

Thanks
Scopus's website on content policy and selection gives a good idea of what you need. The book policy is probably the relevant one, since conference proceedings are "edited volumes", but if you're trying to index individual papers then look at the conference papers selection criteria at the bottom of the page.