Actual Color Research Articles

The use of modern photogrammetric techniques in the inventory of historical monuments - focus on the Potocki Palace in Krzeszowice

The study presents advanced measurement methods used in the inventory of historic buildings, focused on the Potocki Palace in Krzeszowice. The paper focuses on two main measurement methods that allowed comprehensive and accurate documentation to be obtained. The first technique was terrestrial laser scanning, using specialised laser scanners to collect data. In order to reproduce the actual colours and texture of the object under study, the scanning method was supported by photogrammetry. The second method was low-ceiling photogrammetry, which provided even more accurate data about the Palace. Data processing resulted in a three-dimensional (3D) solid, consisting of a multi-million-point cloud. This was followed by a vectorisation process, which made it possible to obtain a full-dimensional representation of the studied object. The results allowed a detailed analysis of the Potocki Palace, including the identification of damage and changes occurring over the years. This documentation provides a solid basis for future conservation, modernisation and research work related to the building. The paper also points out the potential possibilities of using modern technologies to visualize inventoried objects. The technique of Virtual Reality (VR) and showing the object in 3D, which has been popular so far, has recently found even wider possibilities giving input to the construction of so-called Augmented Reality (AR).

EXPRESS: Color Me Effective: the Impact of Color Saturation on Perceptions of Potency and Product Efficacy

Consumers use observable cues, like color, to help them evaluate products. This research establishes that consumers infer greater product efficacy from higher color saturation across seven lab experiments (n = 2,745), a web scraping study, and a field experiment. The studies provide evidence that this belief stems from learned associations between color saturation and potency and is applied to both consumable and durable products. Moreover, consumers overgeneralize this intuition beyond a product’s actual color to a product’s packaging color and the background color used in its advertisements. Two studies support the proposed process with evidence via moderation, while another study identifies consumption goal as a boundary condition, such that high saturation decreases perceived efficacy and purchase intent when consumers search for a gentle (vs. strong) product. The effect is not limited to pre-purchase perceptions but also influences perceptions after actual product use. The effect is established across six hues while holding color lightness constant and has multiple downstream consequences, including purchase intent and consumption amount. The findings have implications for marketers who make product design choices like color choices for products, their packaging, and advertisements, and in instances where consumers may be harmed from underuse or overuse.

Ultrasonographic images and correspondence with real color sectioned images of the upper limb.

For basic training in ultrasonography (US), medical students and residents must learn cross-sectional anatomy. However, the present educational material is not sufficient to learn the sectional anatomy for US. This study aimed to provide a criterion for reading ambiguous structures on US images of upper limb through the sectioned images of Visible Korean. US images of the right arm of a volunteer were scanned (28 planes). For comparison with US images, the sectioned images of the right upper limb (24 bits color, 0.5mm intervals, 0.06mm × 0.06mm sized pixel) were used. After the volume model was constructed from the sectioned images using MRIcroGL, new sectioned images of 28 planes corresponding to the US images of 28 planes were created by adjusting the slope of the volume model. In all images, the anatomical terms of 59 structures from the shoulder to the fingers were annotated. In the atlas, which consists of 28 sets of US images and sectioned images of various slope planes, 59 structures of the shoulder, arm, elbow, wrist, palm, and fingers were observed in detail. We were able to interpret the ambiguous structures on the US images using the sectioned images with high resolution and actual color. Therefore, to learn the cross-sectional anatomy for US, the sectioned images from the Visible Korean project were deemed to be the suitable data because they contained all human gross anatomical information.

Facial expressions affect the memory of facial colors.

Facial color influences the perception of facial expressions, and emotional expressions bias how facial color is remembered. However, it remains unclear whether facial expressions affect daily facial color memory. The memory color effect demonstrates that knowledge about typical colors affects the perception of the actual color of given objects. To investigate the effect of facial color memory, we examined whether the memory color effect for faces varies depending on facial expression. We calculated the subjective achromatic point of the facial expression image stimulus and compared the degree to which it was shifted from the actual achromatic point between facial expression conditions. We hypothesized that if the memory of facial color is influenced by the facial expression color (e.g., anger is a warm color, fear is a cold color), then the subjective achromatic point would vary with facial expression. In Experiment 1, we recruited 13 participants who adjusted the color of facial expression stimuli (anger, neutral, and fear) and a banana stimulus to be achromatic. No significant differences in the subjective achromatic point between facial expressions were observed. Subsequently, we conducted Experiment 2 with 23 participants because Experiment 1 did not account for the sensitivity to color changes on the face; humans perceive greater color differences in faces than in non-faces. Participants selected which facial color they believed the expression stimulus appeared to be, choosing one of two options provided to them. The results indicated that the subjective achromatic points of anger and fear faces significantly shifted toward the opposite color direction compared with neutral faces in the brief presentation condition. This research suggests that the memory color of faces differs depending on facial expressions and supports the idea that the perception of emotional expressions can bias facial color memory.

Pigmentation level of human iPSC-derived RPE does not indicate a specific gene expression profile

Retinal pigment epithelium (RPE) cells show heterogeneous levels of pigmentation when cultured in vitro. To know whether their color in appearance is correlated with the function of the RPE, we analyzed the color intensities of human-induced pluripotent stem cell-derived RPE cells (iPSC-RPE) together with the gene expression profile at the single-cell level. For this purpose, we utilized our recent invention, Automated Live imaging and cell Picking System (ALPS), which enabled photographing each cell before RNA-sequencing analysis to profile the gene expression of each cell. While our iPSC-RPE were categorized into four clusters by gene expression, the color intensity of iPSC-RPE did not project any specific gene expression profiles. We reasoned this by less correlation between the actual color and the gene expressions that directly define the level of pigmentation, from which we hypothesized the color of RPE cells may be a temporal condition not strongly indicating the functional characteristics of the RPE.

Pigmentation level of human iPSC-derived RPE does not indicate a specific gene expression profile

Retinal pigment epithelium (RPE) cells show heterogeneous levels of pigmentation when cultured in vitro. To know whether their color in appearance is correlated with the function of the RPE, we analyzed the color intensities of human-induced pluripotent stem cell-derived RPE cells (iPSC-RPE) together with the gene expression profile at the single-cell level. For this purpose, we utilized our recent invention, Automated Live imaging and cell Picking System (ALPS), which enabled photographing each cell before RNA-sequencing analysis to profile the gene expression of each cell. While our iPSC-RPE were categorized into four clusters by gene expression, the color intensity of iPSC-RPE did not project any specific gene expression profiles. We reasoned this by less correlation between the actual color and the gene expressions that directly define the level of pigmentation, from which we hypothesized the color of RPE cells may be a temporal condition not strongly indicating the functional characteristics of the RPE.

Visible Korean based on true color sectioned images for making realistic digital human, twenty years' record: a review.

Visible Korean (VK) consists of two-dimensional (2D) images and three-dimensional (3D) models. The VK is used in various educational tools and research sources for anatomy. In this paper, we report on the records of the VK over 20years. Research papers related to Visible Korean were reviewed. Through this report of VK records, we highlighted the essential points for making true color and ultra-high-resolution sectioned images of human and animal bodies, for making various 2D and 3D applications from the sectioned images, and for good use of the sectioned images and their applications. In this metaverse age that various virtual environments are required in medical education and research, the VK dataset meets the reality of virtual human models as fundamental data owing to the actual color and high resolution of the VK dataset.

Machine learning-assisted wide-gamut fluorescence visual test paper for propazine determination in fish and seawater samples

Molecularly imprinted polymer (MIP-QDs) with fluorescence quenching ability toward propazine was synthesized for propazine detection. b(Blue)-MIP-QDs were prepared using ZnCdS/ZnS QDs via reverse micro-emulsion, whereas r(red)-MIP-QDs were synthesized using CdSe/ZnS QDs. By utilizing graphene quantum dots (GQDs) as a stable fluorescence intensity reference, the wide-gamut fluorescence test paper was constructed on the basis of mixing b-MIP-QDs, r-MIP-QDs, and GQDs under the optimal ratio. When analyzing spiked propazine in fish and seawater samples using a test paper, satisfactory recoveries of 104.0 %–114.6 % and 92.0 %–96.4 % were obtained, with corresponding limits of detection of 5.0 μg/kg and 1.0 μg/L, respectively. The RGB extractor was utilized to extract the actual fluorescence color and construct a dataset consisting of R, G, and B values, as well as concentration data from 400 samples. The SVR model of Python 3.9.7 was used to obtain and analyze the concentration and feature data. After optimization, the constructed model achieved a correlation coefficient of 0.98 and an RMSE of only 1.81, indicating high prediction accuracy and excellent generalization ability that meet quenching prediction requirements. As an intelligent and rapid detection method, this model holds significant practical significance.

COMPARATIVE ANTHROPOLOGICAL CHARACTERISTICS OF ATTIC WHITE-GROUND VASE PAINTING

Introduction. Of the numerous ceramic production centers of ancient Greece, the Attica region is notable for its continuous development of vase painting styles. Compared to the black-figure and red-figure painting techniques, the polychrome painting of Attic vases on a white-ground may indicate polymorphism in the pigmentation of the ancient Greeks. Materials and methods. The material was collected in digitized museum collections and thematic literature. The color and nature of the characters' hair were studied from vase painting and funerary painting. Anthroposcopic method and simple statistics were used. The significance of differences between groups was assessed using the chi-square test. Results and discussion. In all samples of Attic vase painting, the wavy nature of the hair is predominant, and this frequency does not change significantly over time. The highest frequency of straight nature of the hair (13.3%) is observed in white-ground vase painting. In comparison with the characters in vase paintings, modern Greeks have predominantly straight, lightly wavy hair, especially in women, and then wavy hair. For all style groups of Attic vase painting, no gender differences in nature of the hair were identified. The depiction of hair color on white-ground vase paintings of the early classical and classical times is significantly different: in the earlier vase painting, black and dark brown predominate, and in the later ones, brown/light brown and red-brown. The minimum frequency of dark shades of the hair is noted in Hellenistic funerary painting; it shows, like the white-ground vase painting of the classics, a lighter-pigmented population. The hair color of the modern Greek population is predominantly dark. Based on the hypothesis that the artist depicts familiar forms as traditional ones and reflects the anthropological characteristics of his group, the polymorphism of pigmentation and nature of the hair of the ancient and modern Greek populations is different. Conclusion. Groups of art sources that differ in chronology and style do not represent the hair pigmentation of the population of ancient Greece in the same way. To further study polymorphism of pigmentation of the ancient population, it is necessary to correct the methodology to correlate the actual colors used in vase/mural painting with the hair color classes of the traditional color scale, as well as the use of additional comparative materials.

Deep learning model for dynamic color design of all-dielectric metasurfaces.

Silicon nanostructure colors have rapidly developed in recent years, offering high resolution and a broad color gamut that traditional pigments cannot achieve. The reflected colors of metasurfaces are determined by the geometric structure of the unit cell and the refractive index matching layer parameters. It is evident that the design of specific colors involves numerous parameters, making it challenging to achieve through conventional calculations. Therefore, the tandem network instead of conventional electromagnetic simulation is natural. The forward part of the network incorporates feature cross terms to improve accuracy, enabling high-precision predictions of structural colors based on structural parameters. The average color difference between the predicted and actual color values in the L,a,b color space is 1.38. The network has been proven to accurately predict the refractive index and height of the refractive index matching layer during the dynamic tuning process. Additionally, the issue of the inverse network converging to incorrect solutions was addressed by leveraging the characteristics of the activation function. The results show that the color difference between the colors designed by the inverse network compared to the actual colors in the L,a,b color spaces is only 2.22, which meets the requirements for commercial applications.

Characterization of Pollen Grain and Pollen Extract from Common Allergenic Plants in the Philippines

Allergic rhinitis and asthma are prevalent in tropical countries like the Philippines. Pollen grains from anemophilous plant species may trigger these respiratory allergies. Pollen extracts from common allergenic plants are currently produced locally in the Philippines and are utilized for the diagnosis and immunotherapy of patients with respiratory allergies. Further improvement of their quality is necessary to avoid false negative or false positive diagnoses, as well as to increase the effectiveness of immunotherapy and avoid adverse reactions. This study aimed to characterize the morphology of the collected pollen grains and assess the pollen purity, protein concentration, and electrophoretic profile of the allergenic pollen extracts. Pollen identification and percent purity of the pollen collections were assessed via microscopy and hemocytometer. Lowry assay was performed to identify the total protein concentration of the pollen extracts before subjecting them to SDS-PAGE and silver staining. The pollen samples from varying plant families have distinct features that will aid in their proper identification. Collected aggregates of pollen samples with pollen purity of < 90%, like T. procumbens, A. saman, L. leucocephala, and M. indica, manifest darker colors compared to their actual color. On the other hand, the color of collected pollen samples with pollen purity ≥ 90% are commonly yellow or off-white, which is their natural color. The total protein concentration of the crude pollen extracts ranges from 2.87–9.63 mg/mL. The pollen extracts revealed protein bands at molecular weights ranging from 10–250 kD on SDS-PAGE. Proper characterization of a particular pollen may help in assessing the purity of the collected pollen. Higher pollen purity may contribute to the assurance that the positive diagnosis was due to the target pollen of a plant and not due to contaminations from other components. The result of this study may be considered for the improvement of the crude pollen allergen extract production for clinical use. It is also recommended to assess the effect of the environmental condition where the pollen was collected in terms of the actual proteins present after allergen extraction.

Reliability of the color measurement of resin composites using images obtained using a stereoscopic loupe.

This study assessed the reliability of a color measurement method using images obtained from a charge-coupled device (CCD) camera and a stereoscopic loupe. Disc-shaped specimens were created using the composite Filtek Z350 XT (shades DA1, DA2, DA3, and DA4) (n = 3). CIELAB color coordinates of the specimens were measured using the spectrophotometer SP60 over white and black backgrounds. Images of the same specimens were taken using a CCD camera attached to a stereoscopic loupe. The color of the image was measured (red-green-blue [RGB]) using an image processing software and converted to CIELAB coordinates. For each color coordinate, data from images were adjusted using linear regressions predicting those values from SP60. The whiteness index for dentistry (WID) and translucency parameter (TP00) of the specimens as well as the color differences (ΔE00) among pairwise shades were calculated. Data were analyzed via repeated-measures analysis of variance and Tukey's post hoc test (α = 0.05). Images obtained using the loupe tended to be darker and redder than the actual color. Data adjustment resulted in similar WID, ΔE00, and TP00 values to those observed for the spectrophotometer. Differences were observed only for the WID of shade DA3 and ΔE00 for comparing DA1 and DA3 over the black background. However, these differences were not clinically relevant. The use of adjusted data from images taken using a stereoscopic loupe is considered a feasible method for color measurement.

Characteristic analysis of village cultural landscape by Lian Li space information technology and three-dimensional modelling

Abstract At present, due to the traditional village landscape protection method being relatively single, resulting in the traditional village landscape tends to “homogenization,” which is not conducive to the development of the village cultural landscape. This paper combines spatial information technology and three-dimensional modeling to reconstruct the village landscape and analyze its characteristics. Low-altitude oblique photography technology is used to collect village landscape information from multiple angles and then combined with the 3D model imaging law covariance equations to form the landscape 3D model features and then complete the multi-visual 3D model information matching. Finally, through texture mapping, the 3D model is generated to match the color of the real landscape. Using BIM technology, the data is refined to address the problem of local defects in the landscape 3D reconstruction process. The proposed technology is applied in practice to analyze the spatial comprehensibility of the test village landscape, and the comprehensibility value R² is obtained as 0.317, which is a poor spatial order of the test village. The village residents’ actual landscape color perception of the town ranges from -0.0364 to 0.4566, and the expected range is above 0.7. The actual perception is much lower than the predicted perception, and the subsequent landscape modification should be close to the villagers’ expectations.

Colour prediction as a weaving design selection help tool in Jacquard CAD

The final colour prediction of a weave design made of dyed yarns is a difficult problem. This study shows how a geometric model can be developed to obtain the final colour prediction objectively. For this purpose, a woven material was divided into weft, warp and pores. Then, all parameters needed for the calculation of each colour contribution were identified. A geometrical model based on construction parameters was developed to predict the surface colour contribution of each coloured yarn in a weave surface. To validate the predicted colorimetric data, a visual assessment experiment was conducted. Then, the difference between the predicted and actual colour appearance of the weave pattern was evaluated and analysed in function of weaving structures, and weft yarns colours. For this purpose, simple woven structures (plain, twill 1/3, basket 2/2 and satin Turc) with four coloured weft yarns were used. Results show that the proposed model could correctly predict the final colour of weave designs. Therefore, the model has the potential to eliminate subjective evaluations and reduce prototype sample production by automating the process of weave/colour simulation, thereby reducing the cost and time for product development. The methods of utilization of colour in woven textiles depend upon the composition of the weave design to be woven and the structure parameters of the cloth.

Efficient Contrast Adjustment and Fusion Method for Underexposed Images in Industrial Cyber-Physical Systems

Owing to imaging equipment's environment and limitations, the images obtained in industrial cyber-physical systems (ICPSs) are degraded and available in various visual appearances. The process of highlighting the hidden contents in night-time contrast-distorted images is complex. Earlier approaches have solved this problem from a different perspective and achieved remarkable results that are generally unsatisfactory for images with diverse illumination distortions in ICPSs. Hence, an effective visibility enhancement model is proposed to eliminate inconsistent color casts while highlighting more hidden content for improved inspection, safety in large spaces, and monitoring of large systems. Our proposed model has four steps: 1) removal of the unnatural color cast via a white balance technique, 2) use of probability density and softplus functions to process the images with the actual color cast, 3) using an optimization algorithm to estimate the illumination and adjusting it using a nonlinear function, and 4) blending by multiscale fusion to obtain the most effective visual result. Evaluation of ten benchmark datasets using 14 quality metrics for 22 conventional and modern algorithms shows that our approach is robust, flexible, and applicable to numerous vision-based applications, such as ICPSs, autonomous vehicles, smart cameras, smart mobility, and transportation, especially in low-light environments.

Notes on the identity and taxonomic status of steno endemic <i>Senecio lawsonii</i> Gamble and <i>Senecio lessingianus</i> Gamble and Senecio lessingianus C.B. Clarke (Asteraceae) from the Nilgiri Biosphere Reserve, India

The present article deals with the taxonomic status and the identity of steno endemic Senecio lawsonii Gamble and Senecio lessingianus C.B. Clarke (Asteraceae). Senecio lessingianus is reinstated here as a separate species. An updated nomenclatural citation, a detailed description, SEM images of pollen grains, phenology and notes on actual range distribution, conservation status and colour photo plates of the species are provided here to facilitate easy identification.

Automatic, Early Color-Specific Neural Responses to Object Color Knowledge.

Some familiar objects are associated with specific colors, e.g., rubber ducks with yellow. Whether and at what stage neural responses occur to these color associations remain open questions. We recorded frequency-tagged electroencephalogram (EEG) responses to periodic presentations of yellow-associated objects, shown among sequences of non-periodic blue-, red-, and green-associated objects. Both color and grayscale versions of the objects elicited yellow-specific responses, indicating an automatic activation of color knowledge from object shape. Follow-up experiments replicated these effects with green-specific responses, and demonstrated modulated responses for incongruent color/object associations. Importantly, the onset of color-specific responses was as early to grayscale as actually colored stimuli (before 100ms), the latter additionally eliciting a conventional later response (approximately 140-230ms) to actual stimulus color. This suggests that the neural representation of familiar objects includes both diagnostic shape and color properties, such that shape can elicit associated color-specific responses before actual color-specific responses occur.

Drawing tool incorporating tangible user interface concepts enhancing children's understanding and development of color cognition

The goal of this study was to understand the effect of using an interactive drawing stylus incorporating tangible user interface concepts on color cognition, drawing behaviors, and drawing outcomes among students in the dawning realism stage. 27 fourth-grade students were invited to participate in a three-week drawing experiment involving drawing exercises and formal drawing experiments first with a typical stylus and then with an interactive drawing stylus. Color cognition tests were administered before and after using the interactive drawing stylus. The study found that the color cognition test results before and after using the interactive drawing stylus indicated that students developed a broader range of associations between hue and tone with the mentioned objects and were better able to consider variations in color tone. Besides, students in the dawning realism stage engaged in more frequent interactions with physical objects when manipulating the interactive drawing stylus to capture object colors. These interactions resulted in more opportunities for observing and comparing the differences between the actual object color and the captured color, which enabled them to develop further insight about abstract color concepts.

Using Bayesian regulated neural network (BRNN) to predict the effect of plasma treatment on the fading effect of cotton fabric

The utilization of plasma treatment as a technique for fading the colours on textiles is an environmentally friendly approach. However, the challenge lies in the continuous adjustment of its parameters to attain desired fading colour effects. This is due to the unclear mechanism causing changes in fading effect as a result of alterations in plasma treatment parameters. This research endeavours to predict the alteration of fading effect after plasma treatment of cotton fabrics under varying parameters through the development of a prediction system based on a Bayesian Regulated Neural Network (BRNN) with 10-fold cross-validation. Through a modular approach, the inputs for the training of BRNN models include initial values of plasma treatment parameters such as colour depth, air (oxygen) concentration, water content, treatment time, and one of the CIE L*a*b* values and K/S values corresponding to cotton materials. The outputs, trained individually by four independent BRNN models, are the final values of four colour variables: CIE L*, CIE a*, CIE b* and K/S. The models were trained and validated through the Bayesian Regularization Algorithm and 10-fold cross-validation on 192 data sets, yielding fitted coefficients of determination R2 of 0.9956, 0.9976, 0.9980 and 0.9687, respectively. Approximately 87.5% − 91.67% of predicted colours were within the range of imperceptible or acceptable differences from actual colours. Hence, the developed artificial intelligence system can aid textile finishers in adjusting the plasma colour fading machine’s parameter settings and selected recipes, thus enhancing efficiency and reducing cost and trial time.

Spectral reflectance estimation from non‐raw color images with nonlinearity correction

AbstractThe spectral reflectance is recognized as the fingerprint of an object surface and has been used to achieve accurate color measurement in textile and other fields. Spectral reflectance can be recovered from color images to preserve high spectral and spatial resolutions simultaneously. However, a color camera commonly supplies a non‐raw color image, which is non‐linear with respect to the scene radiance, and is inappropriate for quantitative analysis. In this study, for non‐raw color images, different nonlinearity correction models are designed and evaluated with respect to different spectral estimation algorithms. The colorimetric and spectral accuracy of spectral estimation after the nonlinearity correction is assessed through both simulation and practical experiments. In the simulation, a large number of spectral images from several datasets are employed to directly verify the effectiveness of the nonlinearity correction. In the practical experiments, the spectral estimation accuracy following the nonlinearity correction is verified directly and indirectly based on actual color images. The resulting linear color image data after the nonlinearity correction can provide better spectral estimation accuracy especially for the PI algorithm with one power‐function based model. Besides, the combination of the simple PI algorithm with the power‐function based model can exceed other combinations comprising complex algorithms and models in both accuracy and efficiency. For the linear color image data, the PI algorithm even surpasses the deep learning‐based methods in certain metric, thus indicating a shallow relationship exists between the linear color image data and the spectral reflectance.