Netflix researchers have unveiled a groundbreaking AI-powered green-screen
technology that revolutionizes the production of realistic visual effects for film and
television.
Netflix researchers have unveiled a groundbreaking AI-powered green-screen
technology that revolutionizes the production of realistic visual effects for film and
television. Dubbed Magenta Green Screen (MGS), it is unlike methods seen before. This
new approach offers faster and more accurate results, allowing directors to preview
shots in real-time during filming.
Magenta Glow to Address Old Challenges
Green-screen technology has long been employed to seamlessly integrate actors into
virtual or pre-recorded backgrounds. However, it faced challenges such as colour
inconsistencies caused by green colour spillage, shadows on the green screen, and the
complexities of fine objects like strands of hair. These technical challenges have
demanded extensive manual adjustments, often requiring hours to perfect a single shot.
In response to these limitations, Netflix has developed the Magenta Green Screen
technique. Utilizing a combination of bright green LEDs as the background and front-
facing red and blue LEDs to illuminate the actors, Netflix’s new method creates a
distinctive magenta glow.
By capturing the green channel for the background and the red and blue channels for
the foreground, film editors can replace the green channel in real-time, effortlessly
placing actors in alternative scenes while overcoming obstacles like transparent objects
or hair strands.
AI-Powered Color Correction
However, a slight drawback of this method is that the actors may appear magenta-tinted
due to the absence of a green channel. To address this, Netflix employs artificial
intelligence to reintroduce the full range of colors into the foreground.
Although this AI process currently operates at a fast but non-real-time pace, techniques
like approximating a green channel through red and blue channel averaging enable
directors to monitor the shots effectively during filming.
While the industry welcomes new advancements, experts like Drew Lahat from video
production company Geiger Post caution that the Magenta Green Screen technique
involves several complex steps, which may not be well-suited for the fast-paced nature
of film and television production. It would need to compete with other emerging
technologies like virtual production stages and win over producers in real-world
scenarios.
Green screen technology has a rich history dating back to the 1939 film “The Wizard of
Oz.” However, Netflix’s Magenta Green Screen presents a promising leap forward,
combining AI-powered innovation with real-time compositing capabilities, allowing
filmmakers to focus on artistic excellence while creating visually stunning productions.
How the New Tech Works
By training an AI model on supplementary footage featuring the foreground subject
filmed under traditional white lighting, the researchers enable the model to grasp the
intended appearance and effectively eliminate the tint after the fact.
The benefits of this innovative technique go beyond just speed and accuracy. Unlike
conventional approaches, it doesn’t impose any restrictions on what the on-screen
talent can wear. In a test footage, a performer gracefully adorns a stunning green dress
and holds a glass bottle of the same shade—remarkably, neither vanishes when the
green backdrop is replaced.
However, every silver lining comes with its cloud, and the newfound approach
introduces a set of fresh challenges. The magenta tint enveloping the entire set can
perplex the crew, making it arduous to accurately visualise and preview the footage on-
site. Furthermore, the technique currently lacks real-time functionality, unlike the
systems utilised by weather forecasters who seamlessly blend with forecast maps
during live broadcasts.
Nevertheless, the resourceful researchers are determined to surmount these obstacles.
They are actively developing methods to enable real-time color correction, which would
facilitate on-set previews. Even if the immediate results might not be flawless for the
crew, the compromises made could prove worthwhile if the final product captivates
audiences with even greater realism.
