By Maggie Shiels
Technology reporter, BBC News, Silicon Valley
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Technology and movie-making have always gone hand in hand but the latest breakthroughs are changing the very nature of the process.
Those in the industry say that thanks to the role of graphics processing units (GPUs), the director's vision can be more fully realised.
It also means that special effects teams are involved in the making of the movie at a far earlier stage.
In the past, their creations would be done in post-production and not be seen for weeks or even months after a movie has wrapped.
All that is changing thanks to the GPU, according to leading industry players like Richard Kerris, chief technology officer of Lucasfilm, part of Industrial Light and Magic (ILM).
The GPU is a specialised graphics processor that creates lighting effects and transforms objects every time a 3D scene is redrawn. These tasks are mathematically intensive and in the past were done using the brains of a computer known as the central processing unit or CPU.
ILM was started by Star Wars director George Lucas, and is the biggest special effects studio in the business and behind blockbusters like E.T., Star Trek, Terminator, Harry Potter, Transformers and M Night Shyamalan's soon-to-be-released fantasy The Last Airbender.
"The advent of the GPU is really the next big frontier for us. We have seen hundreds of times improvements over the last few months. This is taking Moore's Law out the window," Mr Kerris told BBC News.
"Back in the day, the simplest of special effects rendering took a lot of computing power and a 500-square-foot room back then that really wouldn't operate our phone systems today.
"But, the talent and the understanding of what could be done out of that was able to produce movies like Terminator. It was cutting-edge stuff and getting a computer that was the size of a small automobile to render out simulations of a twister was pretty groundbreaking then," said Mr Kerris.
Speed is key
At the heart of what the GPU does is speed, according to Dominick Spina, product manager for Nvidia, the company that invented the technology.
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"This is a big leap and the amount of data that can be crunched, analysed and documented can be done a lot faster on the GPU than the CPU. On certain simulations, we are talking a 100-200 times improvement," said Mr Spina.
With that kind of acceleration, Dr Jon Peddie, president of Jon Peddie Research says directors are no longer limited by the technology.
"A movie operates at 24 frames a second, and it takes for one of these extraordinary movies that we see anywhere from as few as 12 to as many as 24 hours for one frame.
"So now you have 24 days for a second's worth of film. By using the GPU for this rendering, you can literally reduce that to one 1,000th of what is was. So if it was say 24 hours to do the job, now you can do it in 24 seconds.
"GPU computing is on the cusp of transforming a major part of the computing industry," claimed analyst Rob Enderle, president of the Enderle Group.
"This is to supercomputers what PC's were to mainframes, and I doubt the world will ever be the same again."
'Making the impossible possible'
From a creative standpoint, studios say the technology has been a real boon.
"With this system, the creative process has been transformed from tedious to fun," said Rob Bredow, chief technology officer for Sony Pictures Imageworks, which used Nvidia's GPU to make "Cloudy With a Chance of Meatballs."
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"When an artist can do 10 times as many iterations of an effect in the same amount of time, the quality of the end product will be that much better. Renders that would have taken 45 minutes or more to run on a CPU, are now cut down to 45 seconds," he said.
Mr Kerris from LucasFilm is in total agreement.
"In the past, a lot of times the director would say 'I want this kind of effect' and the team would go away, do their work and a year later come back with it and if it wasn't what you as a director wanted, then the whole process had to get re-instated.
"We are just at the tip of the iceberg in terms of experimentation but already we have seen the impact on some of the films we worked on this summer like Harry Potter.
"There was a final scene at the end of the film that had to do with fire and Dumbledore moving the fire around his head. When the director saw that he could actually direct the fire, he expanded that entire scene so it became a much more prominent scene in the film," explained Mr Kerris.
"GPUs are making the impossible possible in movies, bringing anything from swirling tornadoes to fiery infernos to the big screen," said Nvidia's Mr Spina.
"In the past movies dominated by crazy water, weather and fire effects were nearly impossible to make regardless of budget or timeframe; with the advent of the GPU, artists are able to make these visions a reality."
So what does the future of this technology hold?
"In the next 6-8 months you will see some major films with some incredibly big scenes that are primarily done through GPU's. We are talking about taking it to a new level and doing it in a way where it won't take two years to do," said Mr Kerris.
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"Beyond that, I think GPU's will start to play a part in the home environment. You could hypothesise that a GPU could offload some stuff from the TV processor to give real-time overlays and graphics and data say with a sports game or show.
"You are going to see amazing new amusement centres, virtual reality and augmented reality. All these things will exploit the GPU on a more personal basis," said Dr Peddie.
"We take our mobile phone and with augmented reality we experience the world in a different way. The power of the GPU does that for us. We are at a tipping point," said Dr Peddie.
But at the end of the day, Mr Kerris stressed that when it comes to the movies, all the whizz-bang technology is worth nothing if the story is not up to scratch.
"George Lucas founded the different divisions of Lucasfilm not for technology's sake. In fact he is a very non-tech person. For him technology is a means to an end and it is always the story that counts," stressed Mr Kerris.