Stephen Barber is a surrealism expert who provides the commentary for a new DVD release of “Un Chien Andalou.” This was a short silent film made in 1929 by Luis Bunuel and Salvador Dali which still shocks viewers. Barber tells Jim Fleming how the collaboration worked and the film got made. And we hear the music used. Stephen Barber is the author of a book called “Blows and Bombs: Antonin Artaud: The Biography.”