Combined luminance compression and color constraint for color correction in tone mapping

In this paper, we present a general color correction function (CCF) in tone mapping (TM), which combines luminance compression and color constraint at locally prespecified luminance level. The proposed CCF is derived from the luminance compression function with the color constraint under which the color ratios between the three color channels are preserved and color saturation is controlled. The proposed CCF is developed to locally perform the luminance compression and color saturation control in local TM. Computer simulations with various sets of real, low dynamic range images show the effectiveness of the proposed TM algorithm in terms of the visual quality as well the local contrast.