What's the name of the prelude to Beijing Opera?

Beijing opera belongs to traditional opera, and the prelude of traditional opera is called prelude, so the prelude of Beijing opera is called prelude.

Prelude is a form of drama music. It is a piece of music played in the overture between halftime and field. In old Beijing opera, there was no prelude, only gongs and drums or qupai were used as the transition of the whole drama.