Color gamut mapping plays a crucial role in color management. Depending on the application, it is sometimes desirable to perform color gamut mapping by shifting the lightness and compressing the chroma of an out-of-gamut color while preserving the perceived hue of the color. The term Òperceived hueÓ is used to distinguish between the visual sensation of hue and metric hue angle (e.g., CIELAB hu...

When a color video system with highly accurate color reproduction is designed, a good measure is required for evaluating the image quality including the color reproduction. There are some degradation sources in a total imaging system from image acquisition to image reproduction. Color random noise is one of major degradations which is often added in image capture phase. In this paper, we invest...

Standardized in 1976 as a uniform color space, CIELAB is extensively utilized in color science and engineering applications. CIELAB provides both a color difference formula and correlates for common perceptual descriptors of color. Deficiencies in both areas are well-known, and based on these known limitations, numerous fixes have been developed yielding alternative color difference formulae th...

We describe a spatial extension to the CIELAB color metric that is useful for measuring color reproduction errors of digital images. To compute the error, digital color images are spatially ltered using a pattern-color separable method and then converted into the CIELAB representation. Over patterned regions of the image, the reproduction errors measured using the spatial extension of CIELAB co...

The purpose of this research is to propose an effective color metric which can predict the perceptual image quality for Retinex method. In this paper, we first give a brief introduction of three kinds of typical single Retinex methods to improve the color reproduction. And then, we state the process for obtaining the observer rating value from the subjective evaluation experiment performed unde...

The lack of blue hue constancy has been identified as a significant shortcoming of the CIELAB color space. The CIECAM97s, CIELUV, IPT and MLab color spaces have been proposed as alternatives to CIELAB. Color gradients with fixed anchor values were used as stimuli in a visual experiment. This allowed an efficient comparison of the hue constancy of different color spaces. The results show that IP...