The present paper studies the chromaticity gamut of multi-color printing processes. Heptatone (7color) printing – the most promising variant of multi-color printing – offers a significantly larger gamut than a conventional CMYK printing process, approaching CRT and film gamuts. The behavior of the process in the device-independent CIE-XYZ and CIE-L*u*v* colorimetric spaces is explored using the...

The illumination of the environment undergoes both intensity and spectral changes during the 24 h cycle of a day. Daylight spectral power distributions are well described by low-dimensional models such as the CIE (Commission Internationale de l'Éclairage) daylight model, but the performance of this model in non-daylight regimes is not characterised. We measured downwelling spectral irradiance a...

We analyze the color performance and system efficiency of three commonly employed liquid crystal display modes with a blue LED-pumped red and green quantum dots (QDs) backlight. Based on the measured QD emission spectra, we can achieve 115% color gamut in CIE 1931 and 140% in CIE 1976 color space, while keeping the same energy efficiency as conventional backlights. Next, we apply multi-objectiv...

In this paper we present a method for improving the quality of a searchable index: Collaborative Index Enhancement, or CIE. CIE improves the index quality by feeding the results of searches over an index back into that index, so that the current user can harness the e ort and insight of previous users that searched for the same or similar information. We present four prototype enhanced indices ...

This paper presents an adaptive method to obtain chromaticity and luminance by using CMOS image sensor under various environments. The image sensor for a use of colorimeter is characterized based on the CIE standard colorimetric observer. We use the method of least squares to derive a colorimetric characterization matrix between camera RGB output signals and CIE XYZ tristimulus values. This pap...

This study proposes a feasible method for spectral color reproduction based on a node address array selection technique from CIE tristimulus values. In this method three-dimensional lookup table (3-D LUT) has been constructed to connect the node address array and the spectrum as the source and destination spaces. First we present a general framework for how to reproduce spectral color. Then res...

www.poynton.com [email protected] This FAQ is intended to clarify aspects of color that are important to color image coding, computer graphics, image processing, video, and the transfer of digital images to print. I assume that you are familiar with intensity, luminance (CIE Y), lightness (CIE L*), and the nonlinear relationship between CRT voltage and intensity (gamma). To learn more about t...

The digital image quality assessment is one of the most relevant aspects of contemporary digital image processing. A rapid development of some modern quality assessment techniques in recent years has caused the introduction of some new metrics, much better correlated with the Human Visual System (HVS) than the traditional ones such as the Mean Squared Error (MSE) or PSNR (Peak Signal to Noise R...

The present paper studies two different table-based approaches for the calibration of electronic imaging systems. The first approach, which is the classical one,uses the device-independent CIE-XYZ colorimetric space as an intermediate standard space. Input and output devices such as scanners, displays and printers are calibrated separately with respect to the objective CIE-XYZ space. The calibr...