Color calibration method of large multi-projection screen based on projector-camera system

Abstract

The invention provides a color calibration optimization algorithm based on a projector-camera system, which is used for eliminating influence on immersion and reality sense of an observer caused by color difference of a display system of a large multi-projection screen. In the invention, for the problem of neglecting influence of a camera in the previous algorithm, a high dynamic range image (HDRI) synthesis algorithm based on Pedro image segmentation is proposed so as to establish a mapping relation between an input pixel and an output pixel of the camera; brightness and chrominance of a projector are calibrated at the same time by virtue of a combined function approximation method for a YUV (luminance and chrominance) color space transformation model so as to generate a color lookup table (CLUT); graphic processing unit (GPU) rendering for color calibration is realized based on shading language; and finally the three-channel annular multi-projection screen is taken as an experimental platform to verify effectiveness of the algorithm.

Description

Technical field [0001] The invention relates to a more optimized large-screen color correction optimization method based on a projector-camera system, which improves the color consistency of large-screen images, has high application value for enhancing the immersion of virtual scenes, and belongs to virtual reality technology And display technology. Background technique [0002] Vision is one of the important human perception systems. In order to strengthen the observer's visual perception in a virtual environment, the color consistency of the large-screen display system is particularly important. The multi-projection large-screen virtual environment system is composed of multiple PCs driving multiple projectors. In order to make the multi-channel virtual environment have a strong sense of immersion, it is required that multiple projectors project the same color on the large screen. There are also color differences between different projectors. The projection output characterist...

AI Technical Summary

Problems solved by technology

[0003] Most of the existing color correction methods based on the projector-camera system only perform color correction on the projector, ignoring the influence of the camera

The patent "a color correction method for projectors" (Ding Ying, Fan Jingtao, Yang Huamin, etc., China, 200910067504.4.2009-09-08) considered the influence of the camera, and measured the exposure with a spectrometer under the ambient light conditions near the large screen The time and aperture size are used as the parameters of the camera during the calibration process. This method is simple and easy to operate, but requires professional optical equipment, and due to the unevenness of ambient light, the measured data cannot guarantee uniqueness

Moreover, for multi-projection systems, multiple measurement processes are required, which is not suitable for multi-projection correction virtual environment systems.

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