Spatial gamut mapping for preserving the details of an image

Abstract

The spatial gamut-mapping algorithm (SGMA) overcomes the drawbacks of the widely used color-by-color methods. Spatial gamut mapping can preserve detailed information in original images by performing adaptive gamut mapping in surrounding pixels within the image. However, spatial gamut mapping can result in hue shift and the halo effect. In addition, it only preserves the boundary information outside the color gamut; the resulting gamut-mapped image does not sufficiently preserve the detailed information in the input image. In this paper, we propose an SGMA that utilizes details of the input image. Our approach improves detail that is not effectively represented with conventional spatial gamut mapping. This is done by taking an original image and first implementing gamut mapping of the input image. Then, the details of the input image and gamut-mapped image are extracted. By examining the out-of-gamut region, the details of the input image can be preserved when these values are added to the gamut-mapped image. The resulting image is obtained by clipping out-of-gamut pixels, since these pixels are generated in the process of preserving details. We demonstrated that images obtained using the proposed method are more similar to the input images, compared to images obtained using conventional methods.