关键词: 投影显示, 颜色校正, 亮度响应函数, 最小二乘法

Abstract: Color correction is a key step for improving the visual effect of the projector display image and the understanding degree of the content, and a new correction algorithm is proposed based on color space conversion and Intensity Transfer Function（ITF）. This paper designs a 16×16 gray checkerboard as calibration image for sample; according to the mapping matrix of the projector-camera system, this paper solves the matching sampling points; it selects an empirical parametric curve to match the ITF, and estimates the parameters by the least squares method based on the sampling points; it calculates a color lookup table on the bases of the inverse function of the ITF, in order to achieve the color correction of the projection display image. In order to examine the feasibility and effectiveness, the proposed algorithm is implemented on an LCD projector. The test results show that this algorithm can achieve better display effect after correction, and it is simple and easy to use.

Key words: projection display, color correction, Intensity Transfer Function（ITF）, least square method