Warner Bros. Pictures will release up to 20 films in the large-screen IMAX format over the next three years under an agreement with IMAX Corp. The Burbank studio will begin the arrangement in March 2013 with “Jack the Giant Slayer.” The movie slate includes the next installment in the Superman franchise, “Man of Steel” in June and the second film in “The Hobbit” trilogy from director Peter Jackson, scheduled for release in December 2013. The companies reached a similar, 20-film deal in 2010 that included the releases this year of “Dark Shadows” and “The Dark Knight Rises.” “Warner Bros. and IMAX have a decade-long relationship that has built up a unique distribution platform,” said Dan Fellman, president of domestic distribution for Warner Bros. Pictures. Imax is headquartered in suburban Toronto and has significant operations in the Los Angeles area.