https://hdl.handle.net/10481/58066 2026-04-04T01:37:26Z https://hdl.handle.net/10481/108538 Perception and communication of relevant colours in paintings by observers with colour vision deficiencies Nieves Gómez, Juan Luis; Hernández Andrés, Javier; Gómez Robledo, Luis; Romero Mora, Francisco Javier In a previous work, we empirically analysed the so-called “relevant colours” in paintings. These relevant colours describe the number of colours that stand out for an observer when glancing at a painting. On average, 19 relevant colours were identified, enabling reliable segmentation of colour images via a small palette of colours. The purpose of this study was to analyse how observers with different colour deficiencies (specifically, 11 deuteranopes, 11 protanopes, 3 deuteranomalous and 4 protanomalous observers) perceive the most representative colours in paintings. To achieve this, a set of painting images was presented to these observers. They were instructed to mark those areas within the image that contained a relevant colour via a mouse. The observers visually scanned the entire painting and selected pixels belonging to relevant chromatic areas. The study included 20 images from the Prado Museum in Madrid, Spain. The results revealed that, as expected, the average number of relevant colours identified by all observers was relatively small, consisting of only 9 colours. This number was lower than the average number of colours found for observers with normal colour vision in the earlier study and reveals that dichromatic observers experience a degradation in their mental impressions of the observed paintings. Nevertheless, the results indicate that there is almost no difference in the number of relevant colours obtained between the two types of colour vision deficiencies; deuteranopes seem to be able to use more relevant colours than protanopes need for the same painting (10 and 8 relevant colours, respectively). By analysing the segmentation of pictorial scenes with relevant colours identified for each painting as colour seeds, we inferred how colour-deficient observers perceive and communicate much of the critical chromatic content in a painting. Through maximizing communicative effectiveness and minimizing the cognitive load, our results assess the colour information retained by anomalous observers, indicating that they lose approximately 20% of the representational content compared with normal observers. Grant PID2022-139056NB-I00 funded by MICIU/AEI/10.13039/501100011033 and ERDF/EU. Ministerio de Universidades, PID2022-139056NB-I00. https://hdl.handle.net/10481/86648 Computing the relevant colors which describe the color palette of paintings Nieves Gómez, Juan Luis; Gómez Robledo, Luis; Chen, Y. J.; Romero Mora, Francisco Javier In this paper, we introduce an innovative parameter that allows us to evaluate the so-called “relevant colors” in a painting; in other words, the number of colors that would stand out for an observer when just glancing at a painting. These relevant colors allow us to characterize the color palette of a scene and, on this basis, those discernible colors that are colorimetrically different within the scene. We tried to carry out this characterization of the chromatic range of paints according to authors and styles. We used a collection of 4,266 paintings by 91 painters, from which we extracted various parameters that are exclusively colorimetric to characterize the range of colors. After this refinement of the set of selected colors, our algorithm obtained an average number of 18 relevant colors, which partially agreed with the total 11–15 basic color names usually found in other categorical color studies. https://hdl.handle.net/10481/86647 Computational color analysis of paintings for different artists of the XVI and XVII centuries Romero Mora, Francisco Javier; Gómez Robledo, Luis; Nieves Gómez, Juan Luis We have performed a computational color analysis of images of paintings for six master painters: Titian, Rubens, El Greco, Velázquez, Rembrandt, and Vermeer. These painters show the evolution from the renaissance to the baroque style. Different first and second-order statistical parameters have been obtained and analyzed in order to fix which of them can be common for the different artists and which of them can be representative of a certain period of time or the evolution of the art. The firsts include the orientation and semi-axes ratio of the ellipses that define the gamut in the chromaticity diagram and the dependencies with the frequency of the power of the Fourier transforms. Most differences among artists can be found in the volume and area of the gamut, the number of discernible colors which is greater for Titian, El Greco and Rubens, compared to Velázquez, Rembrandt and Vermeer, the average value of L* and the number of dark pixels. https://hdl.handle.net/10481/58367 Controlling the 3D architecture of Self-Lifting Auto-generated Tissue Equivalents (SLATEs) for optimized corneal graft composition and stability Gouveia, Ricardo; González-Andrades, Elena; Cardona Pérez, Juan De La Cruz; González-Gallardo, María del Carmen; Ionescu, Ana María Andreea; Garzón Bello, Ingrid Johanna; Alaminos Mingorance, Miguel; González Andrades, Miguel; Connon, Che Ideally, biomaterials designed to play specific physical and physiological roles in vivo should comprise components and microarchitectures analogous to those of the native tissues they intend to replace. For that, implantable biomaterials need to be carefully designed to have the correct structural and compositional properties, which consequently impart their bio-function. In this study, we showed that the control of such properties can be defined from the bottom-up, using smart surface templates to modulate the structure, composition, and bio-mechanics of human transplantable tissues. Using multi-functional peptide amphiphile-coated surfaces with different anisotropies, we were able to control the phenotype of corneal stromal cells and instruct them to fabricate self-lifting tissues that closely emulated the native stromal lamellae of the human cornea. The type and arrangement of the extracellular matrix comprising these corneal stromal Self-Lifting Analogous Tissue Equivalents (SLATEs) were then evaluated in detail, and was shown to correlate with tissue function. Specifically, SLATEs comprising aligned collagen fibrils were shown to be significantly thicker, denser, and more resistant to proteolytic degradation compared to SLATEs formed with randomly-oriented constituents. In addition, SLATEs were highly transparent while providing increased absorption to near-UV radiation. Importantly, corneal stromal SLATEs were capable of constituting tissues with a higher-order complexity, either by creating thicker tissues through stacking or by serving as substrate to support a fully-differentiated, stratified corneal epithelium. SLATEs were also deemed safe as implants in a rabbit corneal model, being capable of integrating with the surrounding host tissue without provoking inflammation, neo-vascularization, or any other signs of rejection after a 9-months follow-up. This work thus paves the way for the de novo biofabrication of easy-retrievable, scaffold-free human tissues with controlled structural, compositional, and functional properties to replace corneal, as well as other, tissues