Watch: Richard Linklater talks 'Boyhood' origins

Richard Linklater knew he wanted to make a movie about childhood, but didn't quite know how to tell the story.
So he turned to the idea of filming Boyhood, a story following a boy through his entire childhood.
"I had this grid of one through 12, those grades you have to go through," says Linklater in this clip."That's kind of what you're sentenced to from childhood, you are going to be in school through 12th grade. You're going to live in your parents house."
"Finally, I just had this one big idea," he adds.
Linklater made the movie starring Ethan Hawke, Patricia Arquette and the boy, Ellar Coltrane. The highly-lauded film follows each of them through 12 years.
Watch Linklater talk about the film as Coltrane's Mason grows up from age 5. This exclusive clip is from the Boyhood Digital HD release on Tuesday (Blu-Ray/DVD on January 6).