Judd Apatow is working on a documentary film about comedian George Carlin.

The 52-year-old director has revealed that his next project will be a look at the career of the legendary American comic.

In an interview with The Boston Globe newspaper, Judd said: ''I'm about to start work with my partner Michael Bonfiglio on a documentary about George Carlin.

''So I'm looking forward to watching a lot of Carlin interviews and specials. I think his work turned out to be very prophetic.''

Carlin, who passed away in 2008, was famed for his 'seven dirty words' routine and also appeared in films such as 'Bill & Ted's Excellent Adventure'.

Judd has directed a number of comedy movies during his career, such as 'The 40-Year-Old Virgin' and 'Trainwreck', and admits that he is keen to pay tribute to legends of the genre.

He explained: ''The way the world works now, if you don't organise someone's history it disappears down the digital drain. There are other people out there with a similar strong interest, like Marc Maron, who are part of the podcasting world and the stand-up world. Maybe I'm just the most obsessed.''

Apatow recently helmed 'The King of Staten Island' - a semi-autobiographical comedy-drama about Pete Davidson.

Speaking about that project, Judd said: ''I can't provide much to the world, but I can provide the occasional laugh.

''Also, the film speaks to grief and trauma, even though it's a comedy, and that relates to what we are all experiencing.

''Unlike how I usually work, I wasn't obsessed with making every line funny.

''I have found, in the past, that I have lost authenticity and credibility because people are too funny [in my films]. In the real world people aren't that funny.''