Jointly Optimizing Color Rendition and In-Camera Backgrounds in an RGB Virtual Production Stage

TL;DR

This paper introduces an improved color calibration method for RGB LED virtual production stages, enhancing color accuracy for both in-camera backgrounds and subject rendering by optimizing multiple linear color correction transformations.

Contribution

It presents a novel calibration process that jointly optimizes color correction for visible LED pixels, illuminating pixels, and recorded camera pixels to improve overall color fidelity.

Findings

More accurate skin tones and costume colors in footage.

Better reproduction of in-camera background colors.

Reduced color shifts caused by narrow-band LED spectral output.

Abstract

While the LED panels used in virtual production systems can display vibrant imagery with a wide color gamut, they produce problematic color shifts when used as lighting due to their peaky spectral output from narrow-band red, green, and blue LEDs. In this work, we present an improved color calibration process for virtual production stages which ameliorates this color rendition problem while also passing through accurate in-camera background colors. We do this by optimizing linear color correction transformations for 1) the LED panel pixels visible in the field of view of the camera, 2) the pixels outside the field of view of the camera illuminating the subjects, and, as a post-process, 3) the pixel values recorded by the camera. The result is that footage shot in an RGB LED panel virtual production stage can exhibit more accurate skin tones and costume colors while still reproducing the desired colors of the in-camera background.