Colour Design for Carton-Packed Fruit Juice Packages

The present research studies the relationships between observers’ expectations for 7 fruit juice packages and the colour design of the package. To do this, a two-stage experiment was conducted. At the first stage, we studied perceived colours for the fruit images shown on each package. At the second stage, fruit juice packages with 20 package colours were rated using 5 bipolar scales: colour harmony, preference, freshness, naturalness and product quality. The experimental results show that the observers tended to perceive fruit image colours lighter and more saturated than those measured using colour measuring instruments. Using factor analyses, we classified the 5 bipolar scales into 2 factors: Product Preference and Freshness. Package colour design was found to have significant impacts on both factors: similarity in chroma and hue between package colour and perceived fruit colour would lead to high product expectations. Keywords: colour design; colour harmony; product expectation; perceived image colour</p

Scaling the Outdoor Environment

In this paper, we suggest a protocol for scaling the outdoor environment. This is based on total appearance techniques developed during a study of the food and drink indoor environment in which we related specific physical features to emotions and expectations generated in the viewer. This record was migrated from the OpenDepot repository service in June, 2017 before shutting down

A new algorithm for calculating perceived colour difference of images

Faithful colour reproduction of digital images requires a reliable measure to compare such images in order to evaluate the reproduction performance. The conventional methods attempt to apply the CIE Colorimetry based colour difference equations, such as CIELAB, CMC, CIE94 and CIEDE2000, to complex images on a pixel-by-pixel basis, and calculates the overall colour difference as the averaged difference of each pixel in the image. This method is simple and straightforward but often does not represent the colour difference perceived by human visual system. This paper proposes a new algorithm for calculating the overall colour difference between a reproduced image and its original. The results obtained show that this new metric provides a quantitative measure that more closely corresponds to the colour difference perceived by human visual system

A study of digital camera colorimetric characterisation based on polynomial modelling

The digital camera is a powerful tool to capture images for use in image processing and colour communication. However, the RGB signals generated by a digital camera are device-dependent, i.e. different digital cameras produce different RGB responses for the same scene. Furthermore, they are not colorimetric, i.e. the output RGB signals do not directly correspond to the device-independent tristimulus values based on the CIE standard colorimetric observer. One approach for deriving a colorimetric mapping between camera RGB signals and CIE tristimulus values uses polynomial modelling and is described here. The least-squares fitting technique was used to derive the coefficients of 3× n polynomial transfer matrices yielding a modelling accuracy typically averaging 1 Δ E units in CMC(1:1) when a 3× 11 matrix is used. Experiments were carried out to investigate the repeatability of the digitising system, characterisation performance when different polynomials were used, modelling accuracy when 8-bit and 12-bit RGB data were used for characterisation and the number of reference samples needed to achieve a reasonable degree of modelling accuracy. Choice of characterisation target and media and their effect on metamerism have been examined. It is demonstrated that a model is dependent upon both media and colorant and applying a model to other media/colorants can lead to serious eye-camera metamerism problems

Evaluating colour preference of lighting with an empty light booth

In our recent work, the colour preference of several LED white lights with different correlated colour temperatures (CCT) was investigated with a wide selection of objects. The results highlighted the dominant effect of light itself on the colour preference of lighting. In this study, we similarly implemented two psychophysical experiments with the same lights but with nothing in the light booth. It was found that the subjective ratings for the lit environment of the empty booth were quite close to those of the previous studies that used various coloured objects. Such a finding corroborates our former conclusion that light dominates colour preference and we suspect that this finding can be attributed either to the colour memory of the observers or to the subconscious effect of human vision. Thus, it seems that for general multi-CCT conditions where the light sources do not have very different gamut shapes or object desaturation/oversaturation properties, the preferred white light could be determined by simply asking the observers to rate their preference for the lit environment of the empty light booth. To verify this wild and interesting conclusion and further clarify its applicability, follow-up studies are needed

Influence of Different Cultures and Display Media on Colour Emotions

This study investigates whether colour emotions are affected by different cultures, display media, and subject’s educational backgrounds. Psychophysical experiments were carried out at three locations, two in Britain and the other in Taiwan. In the experiments single colours and colour pairs were presented on Cathode Ray Tube (CRT) monitors and were assessed on four colour-emotion scales. Colour samples used in the previous experiment were accurately reproduced in the present experiments onto CRT monitors. This allows the same colours to be assessed at different locations. The four colour-emotion scales used in the experiments include ‘warm-cool’, ‘heavy-light’, ‘active-passive’, and ‘like-dislike’. A total of 49 subjects took part in the experiments. The experimental data obtained from the three locations were compared. The results show little difference in colour emotions for colour pairs between different cultures (British vs. Taiwanese), different display media (CRT vs. surface colours), and different backgrounds of subjects (design vs. non-design). However, for single colours the scale ‘like-dislike’ show low correlation between data sets. In the previous study an ‘additivity theory’ was developed for predicting colour-pair emotions. The theory predicts the intensity of a colour emotion for a colour pair by the mean value of the colour emotion for individual colours in that pair. The present experimental results show the ‘additivity theory’, which was developed originally for surface colours, also applies to CRT colours

CRI2012: A proposal for updating the CIE Colour Rendering Index

The CIE CRI has been criticized for its poor correl ation with the visual colour rendering of many spiked or narrowband sourc es, its outdated colour space and chromatic adaptation transform and the use of a small number of non-optimal reflectance samples, which ha ve enabled lamp manufacturers to tune the spectrum of a light sourc e to yield, in some cases, inappropriately high general CRI values. The CRI2012 metric proposed in this paper addresses these criticisms b y combining the most state of the art colorimetric colour difference mod el, i.e. CAM02-UCS, with a mathematical reflectance set that exhibits a high ly uniform spectral sensitivity (to preclude gaming). A set of 210 real reflectance samples has also been selected to provide additional informatio n on the expected colour shifts when changing illumination.status: publishe