GhostFrame demonstrated how it enables multiple backgrounds to be captured at the same time during virtual production shoots at NAB 2023.
The company made it possible for numerous backgrounds to be filmed live simultaneously, while the actors only see a single background on the LED Volume Stage display.
The additional backgrounds are ‘hidden’ in the display, using a blend of patented technology, software and hardware components from GhostFrame founders – AGS, Roe and Megapixel VR.
Together, the technology combines hidden chroma key compositing, hidden tracking, and multiple source video feeds into a single production frame.
The creative team chooses which elements are visible to the human eye on the LED Volume Stage and which backgrounds are visible only to the camera.
GhostFrame demonstrated four different backgrounds being captured simultaneously – one showing a car driving in the daytime down the Las Vegas strip, another showing a car driving down the strip at night, a third video showing an expansive desert backdrop and a fourth feed capturing the actor in front of a greenscreen display.
Mirrors in the studio, and other metallic objects in the foreground showed real-time reflections of the different backgrounds, so each of the four scenes being captured looked exactly as they would do in a normal virtual production shoot.
From a technical point of view, GhostFrame works through advanced nanosecond alignment of video subframes and the camera shutter.
By controlling the LED panels subframe output, cameras can align the shutter angle and capture the desired moment in time within a frame.
AGS are behind the patented ability to hide multiple images in the LED wall, Roe are the display manufacturers and Megapixel VR create the small circuit board (called the PX1 card) that’s installed into the display to enable the GhostFrame effect to work.
GhostFrame has so far been used on virtual production projects including Fox’s NFL Sunday studio, where four cameras each view their own different virtual perspectives on the LED wall at the same time.
Different audiences are fed the same footage with alternative backgrounds, opening up opportunities to reach a far wider audience demographic without requiring any post-production work.
AGS CEO Peter Angel, told Broadcast Tech at NAB 2023: “Some of the potential applications for GhostFrame include enabling multi-camera broadcasts from a virtual production environment; regionalisation, where different languages and brands are displayed depending on the territory; a plethora of creative effects and options in both virtual production and live events; and to capture a greenscreen version for everything that’s shot, providing complete flexibility for the production.”