Parametric effects on the evaluation of threshold chromaticity differences using red printed samples

This paper was published in JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: https://doi.org/10.1364/JOSAA.36.000510. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.[EN] Results from different authors showed deviations of radial orientation in the a*-b* plane (tilt) for the major axes of chromaticity-discrimination ellipses centered around the International Commission on Illumination (CIE) red color center [Color Res. Appl. 3, 149 (1978)], which are not considered by most of the current advanced color-difference formulas (e.g., CIEDE2000). We performed a visual experiment using red printed samples in order to test the influence of the separation between samples (gap) on the mentioned tilt. Our results confirm a counterclockwise tilt of fitted a*-b* ellipses with a magnitude of approximately 36 degrees for samples with no separation, which is similar to that detected by other authors, and a reduction of the mentioned tilt owing to the separation of the samples. We detected a tilt of approximately 22 degrees for samples with a black gap of 0.5 mm and a tilt of approximately 25 degrees for samples with a white gap of 3 mm. Notably, the uncertainty of previous values given by the corresponding credibility intervals of 95% posterior probability is approximately +/- 8 degrees of the mean values. Finally, we study the performance of the most widely used color-difference formulas in the graphic arts sector using our current experimental results, and conclude that the performance of the CAM02-SCD and CAM02-UCS color-difference formulas is significantly better than that of the CIEDE2000 formula.Brusola Simón, F.; Tortajada Montañana, I.; Jorda-Albiñana, B.; Melgosa, M. (2019). Parametric effects on the evaluation of threshold chromaticity differences using red printed samples. Journal of the Optical Society of America A. 36(4):510-517. https://doi.org/10.1364/JOSAA.36.000510S510517364Melgosa, M. (2007). Request for existing experimental datasets on color differences. Color Research & Application, 32(2), 159-159. doi:10.1002/col.20300Luo, M. R., Cui, G., & Rigg, B. (2001). The development of the CIE 2000 colour-difference formula: CIEDE2000. Color Research & Application, 26(5), 340-350. doi:10.1002/col.1049Luo, M. R., & Rigg, B. (1986). Chromaticity-discrimination ellipses for surface colours. Color Research & Application, 11(1), 25-42. doi:10.1002/col.5080110107Alman, D. H., Berns, R. S., Snyder, G. D., & Larsen, W. A. (1989). Performance testing of color-difference metrics using a color tolerance dataset. Color Research & Application, 14(3), 139-151. doi:10.1002/col.5080140308Berns, R. S., Alman, D. H., Reniff, L., Snyder, G. D., & Balonon-Rosen, M. R. (1991). Visual determination of suprathreshold color-difference tolerances using probit analysis. Color Research & Application, 16(5), 297-316. doi:10.1002/col.5080160505Witt, K. (1999). Geometric relations between scales of small colour differences. Color Research & Application, 24(2), 78-92. doi:10.1002/(sici)1520-6378(199904)24:23.0.co;2-mMelgosa, M., Hita, E., Poza, A. J., Alman, D. H., & Berns, R. S. (1997). Suprathreshold color-difference ellipsoids for surface colors. Color Research & Application, 22(3), 148-155. doi:10.1002/(sici)1520-6378(199706)22:33.0.co;2-rIndow, T., Robertson, A. R., Von Grunau, M., & Fielder, G. H. (1992). Discrimination ellipsoids of aperture and simulated surface colors by Matching and paired comparison. Color Research & Application, 17(1), 6-23. doi:10.1002/col.5080170106Xu, H., & Yaguchi, H. (2005). Visual evaluation at scale of threshold to suprathreshold color difference. Color Research & Application, 30(3), 198-208. doi:10.1002/col.20106Huang, M., Liu, H., Cui, G., Luo, M. R., & Melgosa, M. (2012). Evaluation of threshold color differences using printed samples. Journal of the Optical Society of America A, 29(6), 883. doi:10.1364/josaa.29.000883Wen, S. (2012). A color difference metric based on the chromaticity discrimination ellipses. Optics Express, 20(24), 26441. doi:10.1364/oe.20.026441Huang, M., Liu, H., Cui, G., & Luo, M. R. (2011). Testing uniform colour spaces and colour-difference formulae using printed samples. Color Research & Application, 37(5), 326-335. doi:10.1002/col.20689Rich, R. M., Billmeyer, F. W., & Howe, W. G. (1975). Method for deriving color-difference-perceptibility ellipses for surface-color samples. Journal of the Optical Society of America, 65(8), 956. doi:10.1364/josa.65.000956MacAdam, D. L. (1942). Visual Sensitivities to Color Differences in Daylight*. Journal of the Optical Society of America, 32(5), 247. doi:10.1364/josa.32.000247Witt, K. (1995). Cie guidelines for coordinated future work on industrial colour-difference evaluation. Color Research & Application, 20(6), 399-403. doi:10.1002/col.5080200609García, P. A., Huertas, R., Melgosa, M., & Cui, G. (2007). Measurement of the relationship between perceived and computed color differences. Journal of the Optical Society of America A, 24(7), 1823. doi:10.1364/josaa.24.001823Guan, S.-S., & Luo, M. R. (1999). Investigation of parametric effects using small colour differences. Color Research & Application, 24(5), 331-343. doi:10.1002/(sici)1520-6378(199910)24:53.0.co;2-9Montag, E. D., & Wilber, D. C. (2002). A comparison of constant stimuli and gray-scale methods of color difference scaling. Color Research & Application, 28(1), 36-44. doi:10.1002/col.10112Strocka, D., Brockes, A., & Paffhausen, W. (1983). Influence of experimental parameters on the evaluation of color-difference ellipsoids. Color Research & Application, 8(3), 169-175. doi:10.1002/col.5080080308Witt, K. (1990). Parametric effects on surface color-difference evaluation at threshold. Color Research & Application, 15(4), 189-199. doi:10.1002/col.5080150404Xin, J. H., Lam, C. C., & Luo, M. R. (2001). Investigation of parametric effects using medium colour-difference pairs. Color Research & Application, 26(5), 376-383. doi:10.1002/col.1053Cui, G., Luo, M. R., Rigg, B., & Li, W. (2001). Colour-difference evaluation using CRT colours. Part II: Parametric effects. Color Research & Application, 26(5), 403-412. doi:10.1002/col.1056Berns, R. S. (1996). Deriving instrumental tolerances from pass-fail and colorimetric data. Color Research & Application, 21(6), 459-472. doi:10.1002/(sici)1520-6378(199612)21:63.0.co;2-vBrusola, F., Tortajada, I., Lengua, I., Jordá, B., & Peris, G. (2015). Bayesian approach to color-difference models based on threshold and constant-stimuli methods. Optics Express, 23(12), 15290. doi:10.1364/oe.23.015290Saeedi, H., & Gorji Kandi, S. (2018). How anisotropy of CIELAB color space affects the separation effect: an experimental study. Journal of the Optical Society of America A, 36(1), 51. doi:10.1364/josaa.36.000051Yebra, A., Huertas, R., Pérez, M. M., & Melgosa, M. (2002). On the relationship between tilt ofa*b* tolerance ellipses in blue region and tritanopic confusion lines. Color Research & Application, 27(3), 180-184. doi:10.1002/col.1005

Nuevas technologies en la ingeniería de producto: la plataforma OpenDesignet-ODN

El avance de las nuevas tecnologías orientadas al trabajo colaborativo toma como base el uso de las aplicaciones en red bajo la tecnología web 2.0. Más concretamente, existe un campo metodológico innovador en el uso de dichas tecnologías en el proceso de diseño conceptual que permitiría validar y mejorar la transferencia de conocimientos entre diseñadores tanto a nivel profesional como a nivel educativo. Utilizándolo de manera complementaria al uso tradicional de las nuevas TIC que se conciben como meras herramientas supeditadas al proceso conceptual de desarrollo de nuevos productos en sus primeras fases o estadios creativos. La creación de plataformas digitales, como OpenDesignNet ODN, orientada a ofrecer herramientas adaptadas a las necesidades de los diseñadores, permitirá dar a conocer a los nuevos profesionales del diseño dentro de las universidades, aplicaciones específicas que les ayuden a mejorar sus competencias profesionales futuras

How to Elaborate and Interpret an Expert Report on the Design Area

Design has become a strategic element for companies, and every year, there is a growing number of companies and designers who request for industrial property protection (trademarks, patents, industrial designs, etc.). However, all these protection efforts do not prevent cases of unfair competition, and we find many lawsuits and trials focus on possible plagiarism between two designs. Since not all judges or lawyers are trained in this discipline, it is essential to consult a design expert. The expert opinion is summarized in a report that is part of the materials used in the judicial process. This work focuses on these reports centered on design issues, like brands, packaging, graphic design, or industrial products, and has two goals: to give some guidelines for the elaboration of these reports to design experts and to set some keys to interpret and correctly understand this design reports to all that person not expert in design. Methodology, guidelines, and conclusions that appear in this chapter are the result of the work developed by the authors in the last 10 years. Conclusions focus on a set of guidelines to elaborate and interpret correctly an expert report on the design area

Strip-pair comparison method for building threshold color-difference model: theoretical model validation

[EN] This paper presents a method for developing color-difference models near a threshold, based on the serial exploration method described by Torgerson [Theory and Methods of Scaling; Wiley & Sons (1958); Chap. 7], involving the construction of color-control strips of patches arranged in arrays of 2 x n, where n is the number of pairs in the strip. The patches in the lower row should be calorimetrically identical, while the color of the patches in the upper row should vary progressively in constant steps of CIELAB color difference along selected color space vector directions. Prospective observers are instructed to indicate the patch pair number for which they begin to perceive a slight color difference between corresponding patches. The frequency data obtained from the observers was used to build a threshold color-difference model. The intention was to validate the method with theoretical data to determine the effect of the precision with which the strips are constructed, on the accuracy of the estimated parameters. Theoretical frequency data was generated using the CIE94 color difference formula, whose associated color discrimination ellipsoid parameters are very easy to determine, associated with a hypothetical logistic psychometric curve for different color centers. The proposed method allows to determine color discrimination parameters with a precision nearby 4% and an accuracy of 3% with respect to the simulated theoretical parameters, for color samples generated with a standard deviation of Delta E*(ab)=0.2 of the superimposed error around the ideal color difference of pairs of patches.Brusola Simón, F.; Tortajada Montañana, I.; Lengua, I.; Jorda-Albiñana, B.; Peris Fajarnes, G. (2020). Strip-pair comparison method for building threshold color-difference model: theoretical model validation. Optics Express. 28(14):21336-21347. https://doi.org/10.1364/OE.395256S2133621347281

Parametric effects by using the strip-pair comparison method around red CIE color center

[EN] The strip comparison method, based on the serial exploration method described by Torgerson [Theory and Methods of Scaling; Wiley & Sons (1958); Chap. 7], for the development of near-threshold color difference models was presented and validated with theoretical data by the authors in a previous work. In this study, we investigate parametric effects derived from the use of the strip comparison method on chromaticity-discrimination ellipses around the red CIE color center. The results obtained led to the conclusion that the strip comparison method has little effect on the parameters of the chromaticity-discrimination ellipses determined by the pair comparison method when pairs of patches in the strips are separated by a black line 0.5 mm thick or are separated by 3 mm spacing on a white background and also correlates well with the parameters reported by other authors using the pair comparison method at the threshold.Brusola Simón, F.; Tortajada Montañana, I.; Lengua, I.; Jorda-Albiñana, B.; Peris Fajarnes, G. (2020). Parametric effects by using the strip-pair comparison method around red CIE color center. Optics Express. 28(14):19966-19977. https://doi.org/10.1364/OE.395291S1996619977281

La disciplina del diseño gráfico en la formación universitaria del diseñador industrial

El objetivo de este articulo es mostrar la evolución del papel del diseño gráfico en la formación del futuro diseñador industrial en España tal y como se imparten en la Escuela Técnica Superior de Ingeniería del Diseño de la Universidad Politécnica de Valencia, ETSID. La antigua titulación solamente contemplaba dos asignaturas de carácter optativo relacionadas con el diseño gráfico. En la actualidad, con el nuevo plan de estudios, se evidencia una mayor relevancia del diseño gráfico en la formación del futuro diseñador industrial

Bayesian approach for developing threshold color-difference models by the strip-pair comparison method

[EN] A Bayesian approach alternative to the one used in the strip-pair comparison method for developing threshold color-difference models is presented in this paper. Strip-pair comparison method is based on the construction of color-control strips made of pairs of patches put in contact and ordered by increasing the CIELAB color difference. Observers are required to indicate the number of the pair of patches in every strip for which they begin to perceive a just noticeable color difference. Frequency data obtained, from repeating several times the visual assessment, is recorded to build a Bayesian multinomial logistic regression model, which allows the determination of the coefficients of the color discrimination ellipsoids. The results of the Bayesian approach agree closely with the results obtained to validate strip-pair comparison method for the same theoretical frequency data. The main advantage of the Bayesian approach over many other methods is that it allows a direct analysis of the statistical variability of the estimated parameters by means of confidence intervals and other measures of statistical variability.Brusola Simón, F.; Tortajada Montañana, I.; Jorda-Albiñana, B.; Gonzalez-Del-Rio, J.; Lengua, I. (2021). Bayesian approach for developing threshold color-difference models by the strip-pair comparison method. Optics Express. 29(17):26553-26568. https://doi.org/10.1364/OE.432157S2655326568291

Assessment of the effectiveness of the Spanish NGOs brand design

[EN] Currently the brand is a fundamental intangible and therefore achieving an effective design must be considered a priority objective for any organization. This research starts from the identification of the key factors in the design of graphic brands to apply them to the evaluation of the effectiveness degree of a corporate design. Specifically, 273 Spanish NGO brands are analyzed according to the degree of compliance with four criteria (readability, simplicity, association and versatility) and then assess their level of graphic efficiency. The results show that the brands of the NGOs analyzed are located in an intermediate position in terms of efficacy with respect to the measured criteria and that there are opportunities for improvement, especially in the criteria of association and simplicity. It has also been verified that the level of effectiveness of corporate graphics is related to the NGO's annual budget and the type of activity it carries out; but not with the year of creation or with the geographical scope of action. As a key contribution, this work presents a methodology that allows measuring the graphic efficiency of the brands in a sector and assessing the evolution of this efficiency over time.[ES] Actualmente la marca es un intangible fundamental y por ello conseguir un diseño eficaz debe considerarse un objetivo prioritario para cualquier organización. Esta investigación parte de la identificación de los factores clave del diseño de marcas gráficas para aplicarlos a la valoración del grado de eficacia de un diseño corporativo. En concreto, se analizan 273 marcas de ONG españolas en función del grado de cumplimiento de cuatro criterios (legibilidad, simplicidad, asociación y versatilidad) para después valorar su nivel de eficacia gráfica. Los resultados muestran que las marcas de las ONG analizadas se ubican en una posición intermedia en cuanto a eficacia con respecto a los criterios medidos y que existen oportunidades de mejora, sobre todo en los criterios de asociación y simplicidad. También se ha comprobado que el nivel de eficacia del grafismo corporativo está relacionado con el presupuesto anual de la ONG y el tipo de actividad que desarrolla; pero no con el año de creación ni con el ámbito geográfico de actuación. Como aportación clave, este trabajo presenta una metodología que permite medir la eficacia gráfica de las marcas de un sector y valorar la evolución de esta eficacia a lo largo del tiempo.Tarazona-Belenguer, N.; Ampuero-Canellas, O.; Gonzalez-Del-Rio, J.; Jorda-Albiñana, B. (2021). Valoración de la eficacia del diseño de marca de las ONG españolas. ArDIn: Arte, Diseño e Ingeniería. 10:92-121. https://doi.org/10.20868/ardin.2021.10.4529S921211

Merchandising en museos: ¿educación, cultura o simple negocio?

Actualmente, el merchandising de un museo constituye una buena manera de financiación pero en su gestión no debería perderse el fin educativo y cultural que define a estas instituciones. De hecho, un tratamiento adecuado de estos productos y de la tienda puede convertirlos en una prolongación del espacio expositivo y en transmisores de conocimiento, arte y cultura. Para conseguirlo se proponen algunas estrategias como la personalización, la elección de productos de calidad, el cuidado del packaging y la incorporación de contenidos clave. Todo ello posicionará al museo como entidad difusora de cultura y lo alejará del mero negocio comercial

Una mirada del diseño sobre la morfología de los caracteres caligráficos y sus implicaciones en el proceso de alfabetización de adultos

A través de un tratamiento metodológico cualitativo, el presente estudio tiene por objetivo comparar los elementos constructivos de la escritura cursiva con la escritura normal o romana, a través de un análisis morfológico de los caracteres (mayúsculos y minúsculos) y sus implicaciones en términos de uso y facilidad de ejecución en el proceso de alfabetización de adultos. La relación entre aspectos históricos, ergonomía y facilidad de uso, suscita una discusión sobre la forma en que el diseño de las letras puede constituir un elemento complicado para el adulto analfabeto. De igual manera se plantea cómo el diseño puede contribuir a minimizar los impactos negativos de la relación del estudiante con el universo de las letras.Pacheco, A.; Jorda-Albiñana, B.; Gonzalez-Del-Rio, J.; Mazarelo Maciel-Pacheco, K. (2013). Una mirada del diseño sobre la morfología de los caracteres caligráficos y sus implicaciones en el proceso de alfabetización de adultos. Revista IconoFacto. 9(12):98-107. http://hdl.handle.net/10251/80213S9810791