In everyday experience, perceived colors of objects remain approximately constant under changes in illumination. This constancy is helpful for identifying objects across viewing conditions. Studies on color constancy often employ monitor simulations of illumination and reflectance changes. Real scenes, however, have features that might be important for color constancy but that are in general no...

In many, but not all societies, dark skin color is associated with high blood pressure. Whether the association between skin color and blood pressure is independent of known determinants of blood pressure remains controversial. We examined the association between skin color and blood pressure in 835 Egyptian adults (370 men and 465 women) participating in the National Hypertension Project, a na...

A new approach to color image compression with high compression ratios and good quality of reconstructed images using quantization, thresholding, and edge detection all based on the moment-preserving principle is proposed. An input image with 24 bits per pixel is quantized into 8 bits per pixel using a new color quantization method based on the moment-preserving principle. The quantized image i...

Thermal oxidation, heat, oxidation and reagents stability was examined as an index of fatty acid stability. Color determination and chemical test to indicate values such as those of anisidine and peroxide are usually conducted according to conventional methods for stability determination. In particular, color determination is usually done by methods such as the APHA and Gardner color methods. V...

Humans have always seen the world in color. In the last three decades, there has been rapid and enormous transition from grayscale images to color ones. Well-known objective evaluation algorithms for measuring image quality include mean squared error (MSE), peak signal-to-noise ratio (PSNR), and human Visual System based one are structural similarity measures and edge based similarity measures....

Conventional white-light sources suffer from a fundamental trade-off between color rendering index and the luminous efficacy; increasing one generally comes at the expense of the other. We demonstrate through simulation that dual-wavelength blue-emitting active regions in phosphor-converted white light sources maximize the output luminous flux while significantly increasing the color rendering ...

In this paper, we present a new algorithm that automatically classifies the pH level on a test strip using color image processing techniques. This algorithm is implemented on a camera phone that captures color images of pH test strips for healthcare or medical purpose. Experimental results show that this new approach is more robust in handling reflection and skewed placements of the test strip...

Integrated color indices corrected for galactic absorption, internal absorption, and redshift have been given for a large number of galaxies by de Vaucouleurs and de Vaucouleurs (1964). These indices may be compared with the maximum rotational velocities of galaxies that are listed in compilations by Brosche (1967, 1971). Such a comparison shows that there is a strong correlation between the in...

Color constancy is usually measured by achromatic setting, asymmetric matching, or color naming paradigms, whose results are interpreted in terms of indexes and models that arguably do not capture the full complexity of the phenomenon. Here we propose a new paradigm, chromatic setting, which allows a more comprehensive characterization of color constancy through the measurement of multiple poin...