While in Hollywood music is often added when a film is in the editing phase, the planning for the songs in Bollywood projects can take as much work as the script itself.
The music is as integral to the success of the film as the stars, screenplay and even the director.
Soundtracks are a major part of a film's promotion, timed to come out in the weeks before release to give maximum exposure. A hit film will almost inevitably see soundtrack songs in the top 10.
The Indian music legend AR Rahman, who will perform in Dubai on December 9, produced the soundtrack to the film Rockstar - and it came out a month before the film's release last week. The composer is known for his ability to mix Indian classical music with orchestral arrangements and pop; he famously did the music for Slumdog Millionaire and also when Andrew Lloyd Webber put on the ill-fated musical Bollywood Dreams. Any release from the artist is met with huge anticipation, all the more so when it ties into a movie.
"It took around two years to develop," says the Rockstar director Imtiaz Ali. "It was still going on right up to the release of the film. Music is something I enjoy doing a lot. It's one of the benefits of a filmmaker, to be able to work on the songs, even more so this time because it was working with Rahman. I spent more time in his studio than in my home in the past two years, it is thrilling and soul-searching to be involved in the music."
Rajinder Dudrah, a senior lecturer in film and media studies at the University of Manchester, has written a new book called Bollywood Travels due out next year.
"In some cases the film's recorded soundtrack as an album of up to several songs and additional music can do far better commercially than some of the films at the box office," says Dudrah. "A good example of this is the 1990 film Aashiqui directed by Mahesh Bhatt, which was one of the highest-selling soundtracks of the 1990s. The film was considered weak by critics and audiences alike, but was made a hit due to its successful soundtrack." Quentin Tarantino is one of the rare examples of a Hollywood director known for the soundtracks that accompany his films.
"I've always thought my soundtracks do pretty good, because they're basically professional equivalents of a mix tape I'd make for you at home," he says.
In contrast to Bollywood soundtracks, however, Tarantino sticks to pre-recorded music for his films.
He argues that he's spent so long creating a film that he doesn't want someone else to come along and mess up his music.
Indeed, most of the successful soundtracks this year in American film, such as Drive, starring Ryan Gosling, have featured pre-recorded music that has not dented the album charts.
Of course, one of the major differences is that songs are nearly always incorporated into the scenes of Bollywood films, whereas this usually only happens in musicals in American cinema.
Often the music will act as a leitmotif running throughout the film that will indicate the emotional state of the character or to indicate a heightened sense of drama. The lyrics are also used to propel the plot forward, with the song and dance allowing for a break in proceedings.
The success of Bollywood soundtracks to promote films has also seen some artists resort to underhanded behaviour to promote their own wares.
The song Bhool Na Jaana Rehmat by Shrey Singhal was released on the internet with a claim it came from the soundtrack of the forthcoming Don 2 movie, a claim that was later shot down by the filmmakers. "There is a fake song claiming to be from Excel Entertainment's forthcoming Don 2 doing the rounds on the internet and with the popularity that the film and character has amongst the audiences, fans are downloading the song as they think it's from the film," said a statement issued by the film's publicist. "Please note that the song is not from the film and someone is just using it to publicise that particular song."
The 2006 movie Don - Chase Begins, was a remake of the 1978 movie Don, starring Amitabh Bachchan. Directed by Farhan Akhtar and starring Shah Rukh Khan, the film was one of the biggest hits in Bollywood history.
The sequel, which is to be released on December 23, is expected to prove a blockbuster at the box office and on the music charts.