Target Color Research Articles

Intelligent classifier for various degrees of coffee roasts using smart multispectral vision system

AbstractThis study proposes an innovative deep learning model for use in a multispectral vision system comprising a complementary metal‐oxide semiconductor image sensor and a spectrometer. To ensure accurate color recognition, the deep learning model includes an embedded adaptive automatic color temperature correction engine. By using this color temperature correction engine, the multispectral vision system can intelligently compensate for lighting and chromatic variations. To evaluate the performance of the system, we created a nine‐dimensional data set using the IT8.7/2 color target. We then used this data set to train the deep learning model. Our deep learning model outperformed other lightweight deep learning models in experiments, making it suitable for deployment on edge devices and embedded systems. We tested the ability of the multispectral vision system to classify adulterated coffee beans into their respective classes. The overall accuracy rate was more than 99.3%, indicating that out proposed multispectral vision system is effective in identifying color differences. Considering its capabilities in agricultural screening, we suggest incorporating our adaptive automatic multispectral vision system into agricultural machines for the realization of Agriculture 4.0.

The Classic Stroop Asymmetry Works for Spoken as Well as Written Words

In modern versions of the Stroop task, participants view target words presented on a computer screen with pixels that are either congruent (e.g., “Red” in red pixels) or incongruent (e.g., “Red” in blue pixels) with the meaning of the target word. When participants report the target color, the difference in response time between congruent and incongruent targets (i.e., Stroop effect) is typically larger than when they report the target word (i.e., reverse Stroop effect); this is the classic Stroop asymmetry. For decades following Stroop’s experiments, the prevailing explanation for the asymmetry asserted that, for most people, word reading but not color naming has become automatic, so the target word should always become mentally accessible before the target color. Recent studies have argued instead that the advantage for the target word results not from automaticity but from a strong association between the identification task and verbal processing. To test the strength-of-association account, we developed Qualtrics scripts to deliver visual and auditory target words in Stroop and reverse Stroop tasks. The visually presented targets replicated the classic Stroop asymmetry, p < .001, ηp2 = .27. The auditorily presented targets extended the classic Stroop asymmetry to the auditory domain, p < .001, ηp2 = .18. These results support the argument that, for an identification task, the target’s semantic features enjoy an advantage over the target’s perceptual features regardless of the sensory modality to which the target is presented. In turn, this shows that task demands are more important than automaticity in mental processing.

Targeted color design of silver-gold alloy nanoparticles.

This research article focuses on the targeted color design of silver-gold alloy nanoparticles (NPs), employing a multivariate optimization approach. NP synthesis involves interconnected process parameters, making independent variation challenging. Data-based property-process relationships are established to optimize optical properties effectively. We define a color target, employ a green chemical co-reduction method at room temperature and optimize process parameters accordingly. The CIEL*a*b* color space (Commission Internationale de l'Éclairage - International Commission on Illumination) and Euclidean distances facilitate accurate color matching to establish the property-process relationship. Concurrently, theoretical Mie calculations explore the structure-property relationship across particle sizes, concentrations, and molar gold contents. The theoretically optimal structure agrees very well with experimental particle structures at the property-process relationship's optimum. The data-driven property-process relationship provides valuable insights into the formation mechanism of a complex particle system, sheds light on the role of relevant process parameters and allows to evaluate the practically available property space. Model validation beyond the original grid demonstrates its robustness, yielding colors close to the target. Additionally, Design of Experiments (DoE) methods reduce experimental work by threefold with slight accuracy trade-offs. Our novel methodology for targeted color design demonstrates how data-based methods can be utilized alongside structure-property relationships to unravel property-process relationships in the design of complex nanoparticle systems and paves the way for future developments in targeted property design.

The software for improvement of image quality after enlargement

In the paper digital images of various formats were investigated. The different vector image formats have different color rendering capabilities. The main task was to achieve a result of refinement of the random low resolution color raster image without quality and resolution loss. The biggest advantage of using specific vector or compressed raster formats is the ability of scaling without quality loss and comparatively small file size. This eases vector images transfer through networks. In the article a specific algorithm of raster images refinement was investigated, particularly the method of raster images refinement based on combination of interpolation algorithms with and without square root of the color values. The key point of the method is comparison and combination of vertical, horizontal and diagonal interpolation that allows to achieve better precision on color depth calculation. This exact method was never used in commercial of scientific software though there are different variation of combined interpolation methods similar to current one. In this paper two different approaches to image matrix re-calculation during image refinement were tested, in order to research how root squaring the value of color depth would affect the target color value. The result shows that this approach allows to keep more details in shadows and save contours during interpolation though the images lose somewhat of color depth. The experiment shows that this interpolation method with square rooting color values allows to enlarge and refine color images with complex tone curve structure and keep details of the objects in place, though color depth is worsened especially in deepest shades and blacks. On the opposite the method of combined interpolation without root squaring gives significantly better result with color interpolation but loses details in the dark areas of the initial image. The suggested method can be used in a number of different areas

Do We Prepare for What We Predict? How Target Expectations Affect Preparatory Attentional Templates and Target Selection in Visual Search.

Visual search is guided by representations of target-defining features (attentional templates) that are activated in a preparatory fashion. Here, we investigated whether these template activation processes are modulated by probabilistic expectations about upcoming search targets. We tracked template activation while observers prepared to search for one or two possible color-defined targets by measuring N2pc components (markers of attentional capture) to task-irrelevant color probes flashed every 200 msec during the interval between search displays. These probes elicit N2pcs only if the corresponding color template is active at the time when the probe appears. Probe N2pcs emerged from about 600 msec before search display onset. They did not differ between one-color and two-color search, indicating that two color templates can be activated concurrently. Critically, probe N2pcs measured during two-color search were identical for probes matching an expected or unexpected color (target color probability: 80% vs. 20%), or one of two equally likely colors. This strongly suggests that probabilistic target color expectations had no impact on search preparation. In marked contrast, subsequent target selection processes were strongly affected by these expectations. We discuss possible explanations for this clear dissociation in the effects of expectations on preparatory search template activation and search target selection, respectively.

Autism-related traits are related to effectiveness of immersive visual guidance on spatial cognitive ability: a pilot study

A head-mounted display could potentially restrict users’ visual fields and thereby impair their spatial cognitive ability. Spatial cognition can be assisted with immersive visual guidance. However, whether this technique is useful for individuals with autism-spectrum disorder (ASD) remains unclear. Given the recent virtual reality (VR) contents targeting individuals with ASD, the relationship between ASD-related traits and the effectiveness of immersive visual guidance should be clarified. This pilot study evaluated how ASD-related traits (autistic traits and empathizing–systemizing cognitive styles) among typically developing individuals are related to the effectiveness of visual guidance. Participants performed visual search and spatial localization tasks while using immersive visual guidance. In the visual search task, participants searched immersive VR environments for a target object and pushed a button according to the target color as quickly as possible. In the localization task, they viewed immersive visual guidance for a short duration and localized the guided direction via a controller. Results showed that visual search times were hastened with systemizing cognition. However, ASD-related traits were not significantly related to localization accuracy. These findings suggest that immersive visual guidance is generally useful for individuals with higher ASD-related traits.

Contribution of speech rhythm to understanding speech in noisy conditions: Further test of a selective entrainment hypothesis.

Previous work by McAuley et al. Attention, Perception, & Psychophysics, 82, 3222-3233, (2020), Attention, Perception & Psychophysics, 83, 2229-2240, (2021) showed that disruption of the natural rhythm of target (attended) speech worsens speech recognition in the presence of competing background speech or noise (a target-rhythm effect), while disruption of background speech rhythm improves target recognition (a background-rhythm effect). While these results were interpreted as support for the role of rhythmic regularities in facilitating target-speech recognition amidst competing backgrounds (in line with a selective entrainment hypothesis), questions remain about the factors that contribute to the target-rhythm effect. Experiment 1 ruled out the possibility that the target-rhythm effect relies on a decrease in intelligibility of the rhythm-altered keywords. Sentences from the Coordinate Response Measure (CRM) paradigm were presented with a background of speech-shaped noise, and the rhythm of the initial portion of these target sentences (the target rhythmic context) was altered while critically leaving the target Color and Number keywords intact. Results showed a target-rhythm effect, evidenced by poorer keyword recognition when the target rhythmic context was altered, despite the absence of rhythmic manipulation of the keywords. Experiment 2 examined the influence of the relative onset asynchrony between target and background keywords. Results showed a significant target-rhythm effect that was independent of the effect of target-background keyword onset asynchrony. Experiment 3 provided additional support for the selective entrainment hypothesis by replicating the target-rhythm effect with a set of speech materials that were less rhythmically constrained than the CRM sentences.

The role of brain oscillations in feature integration.

Our sensory system is able to build a unified perception of the world, which although rich, is limited and inaccurate. Sometimes, features from different objects are erroneously combined. At the neural level, the role of the parietal cortex in feature integration is well-known. However, the brain dynamics underlying correct and incorrect feature integration are less clear. To explore the temporal dynamics of feature integration, we studied the modulation of different frequency bands in trials in which feature integration was correct or incorrect. Participants responded to the color of a shape target, surrounded by distractors. A calibration procedure ensured that accuracy was around 70% in each participant. To explore the role of expectancy in feature integration, we introduced an unexpected feature to the target in the last blocks of trials. Results demonstrated the contribution of several frequency bands to feature integration. Alpha and beta power was reduced for hits compared to illusions. Moreover, gamma power was overall larger during the experiment for participants who were aware of the unexpected target presented during the last blocks of trials (as compared to unaware participants). These results demonstrate that feature integration is a complex process that can go wrong at different stages of information processing and is influenced by top-down expectancies.

Contingent capture by color is sensitive to categorical color perception.

Contingent capture (CC) theory postulates that attention can only be captured by top-down matching stimuli. Although the contingent capture of attention is a well-known and thoroughly studied phenomenon, there is still no consensus on the characteristics of the top-down template which guides the search for colors. We tried to replicate the classical contingent capture effect on color (Experiment 1) and then added linguistic processing to this perceptual effect (Experiment 2). In Experiment 1, attention was indeed captured by the cues of the same color as the target, while the cues of different colors were successfully ignored. In Experiment 2, the cue color was never identical to the target color but would either belong to the same linguistic category or not (i.e., linguistic matching and linguistic nonmatching cues). In both cases, cues were made to be equally perceptually distant from the target. Although, attention was captured by both cue types, the degree of capture was significantly higher for linguistic matching cues. Our research replicated the classic contingent capture effect but on color, and also demonstrated the effect of color categories in the search task. In short, we demonstrated the effect of color categories in the search task. Results show that the template for color search contains physical characteristics of color, as well as information about color category names.

The specificity of feature-based attentional guidance is equivalent under single- and dual-target search.

Individuals actively maintain attentional templates to prioritize target-matching inputs. While previous works have established that multiple templates can be held simultaneously, current understanding is limited with respect to the representational quality of such templates. We thus investigated: (a) whether the maintenance of two templates is limited to broad, coarse-grained representations, and if not, (b) whether there is nonetheless a decline in the achievable level of specificity when multiple attentional templates are held simultaneously. Using a spatial cueing procedure, we probed the breadth of attentional templates while participants maintained either one (Experiment 1) or two target colors (Experiment 2) under conditions of low- or high-similarity search and found specific template maintenance during high-similarity search for both single- and dual-target conditions. We then directly compared template specificity during single- and dual-target maintenance in Experiment 3, probing at the point of differentiation between target and nontarget feature values observed during single-target search. Here we found no difference in the selectivity of cue validity effects between single- and dual-target search, suggesting equivalent template specificity regardless of whether one or two features are relevant to search. Lastly, in Experiment 4, we established that such template specificity is dependent on access to visual working memory. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Multi-Intensity Planes Constellation and Code Design-Based Color-Shift Keying for Visible Light Communications

In this study, we develop multi-intensity planes color-shift keying (MIP-CSK) constellations to determine the effect of the MIP-based CSK design scheme on the reliability of visible light communication systems under the constraint of target color constraint. Based on a two-dimensional triangle partition constellation plane, we introduce algorithms to design the non-integral powers of two MIP-CSK constellations in three-dimensional symbol space by using set partition and intensity plane levels, which improves the minimum Euclidean distance. We then develop a coding scheme by designing an finite-state machine from the non-integral powers of two constellations to further improve the reliability under the white color constraint. Subsequently, by considering the spatial symmetric nature of the triangle partition constellation distribution, we study the design strategy of powers of two constellation symbols and further propose the powers of two MIP-CSK design scheme in a three-dimensional symbol space. Moreover, we investigate the reliability benefit obtained by set partition and optimal intensity levels for powers of two MIP-CSK constellations by improving the normalized minimum squared distance. The simulation results indicate that the error performance of the proposed new family of MIP-based design schemes outperforms its counterparts while complying with the white color constraint at the high signal-to-noise ratios.

Mental imagery and visual attentional templates: A dissociation

There is a growing interest in the relationship between mental images and attentional templates as both are considered pictorial representations that involve similar neural mechanisms. Here, we investigated the role of mental imagery in the automatic implementation of attentional templates and their effect on involuntary attention. We developed a novel version of the contingent capture paradigm designed to encourage the generation of a new template on each trial and measure contingent spatial capture by a template-matching visual feature (color). Participants were required to search at four different locations for a specific object indicated at the start of each trial. Immediately prior to the search display, color cues were presented surrounding the potential target locations, one of which matched the target color (e.g., red for strawberry).Across three experiments, our task induced a robust contingent capture effect, reflected by faster responses when the target appeared in the location previously occupied by the target-matching cue. Contrary to our predictions, this effect remained consistent regardless of self-reported individual differences in visual mental imagery (Experiment 1, N = 216) or trial-by-trial variation of voluntary imagery vividness (Experiment 2, N = 121). Moreover, contingent capture was observed even among aphantasic participants, who report no imagery (Experiment 3, N = 91). The magnitude of the effect was not reduced in aphantasics compared to a control sample of non-aphantasics, although the two groups reported substantial differences in their search strategy and exhibited differences in overall speed and accuracy. Our results hence establish a dissociation between the generation and implementation of attentional templates for a visual feature (color) and subjectively experienced imagery.

Visual mental imagery of atypical color objects attracts attention to an imagery-matching object.

Mental imagery attracts attention to imagery-matching stimuli. However, it remains unknown whether voluntarily imagined atypical color also attracts attention to a stimulus that matches the imagery when the imagined stimuli are color-diagnostic objects, which are strongly associated with typical color. This study investigated whether people can voluntarily imagine atypical colors of such objects and attend to imagery-matching stimuli. Participants in the imagery group were instructed to imagine an atypical color of the black-white objects according to the instructed color or voluntarily selected color, whereas participants in the control group were instructed to attend to the objects without any instruction of imagery. Thereafter, they detected a color target in a visual search task. Results revealed that participants in the imagery group directed attention to the imagery-matching atypical color, not to the original color of the object in the search. Meanwhile, participants in the control group did not demonstrate any attentional guidance. These results suggest that voluntarily imagining atypical color can attenuate mental representations of the original color imagery and change attention to a stimulus that matches imagery.

Effect of the spatial location of boundary on colour overflow in Gamut conversion

The colour gamut is an important indicator of the colour performance of a terminal display. Due to the variety of gamut standards and display devices, it is often necessary to convert the gamut to achieve a standardised display when using a terminal to display an image, but gamut conversion can lead to many problems such as colour overflow. This paper examines the problem of colour overflow in gamut conversion for terminal displays. First, a gamut model of the terminal display is established based on the CIE colorimetric principles, and the gamut conversion principles are briefly described based on the gamut model. Secondly, the geometric representation of the gamut boundary surface is obtained by Bessel fitting of the gamut boundary. On this basis, the geometric relationship between the boundary surface of the target colour gamut and the original colour gamut is analysed, the causes and conditions of overflow are analysed, and the overflow ratio is calculated to provide theoretical guidance for the correction of colour overflow in the process of colour gamut conversion of the display terminal.

Investigation into Pigmentation Behaviors and Mechanism of Pigment Yellow 180 in Different Solvents

To achieve the target colors, pigmentation (post-processing) in solvents is a key process in making Pigment Yellow 180 (PY180), a bis azo pigment. In this work, the solvent effect on the pigmentation behavior of PY180 was studied based on the Hansen solubility parameters (HSPs) and the molecular polarity index (MPI) method. First, the samples were characterized using FTIR, XRD, and TEM, and the colorimetric analysis was performed using the CIE L*a*b* color space model. It was found that the color hues obtained in ten solvents are different, with the overall color variation from reddish–yellow to greenish–yellow. Further characterization confirmed that the crystallinity and particle size increase of PY180 during the pigmentation mainly account for the variation of the chromaticity. Then, HSPs were introduced to understand how suspension behavior affects the dissolution–reprecipitation process. It shows that high-quality pigments can be obtained from solvents generally with low HSP differences (Δδ) between the solvents and PY180. To compensate for the inaccurate prediction of the HSPs method, MPI was used to value the influence of solvent molecular polarity. The results show that among solvents with similar solubility parameters to PY180, the stronger the molecular polarity index (MPI) of the solvent, the greater the color variation of the pigments. Meanwhile, different solvents influence the crystallization behavior of the low soluble system, which was supplemented by the above study.

Task-irrelevant valence-preferred colors boost visual search for a singleton-shape target

Some studies have suggested that emotion-associated features might influence attentional capture. However, demonstrating valence-dependent distractor interference has proven challenging, possibly due to the neglect of individuals’ color–valence preferences in standard, averaged reaction-time (RT) measures. To address this, we investigated valence-driven attentional-capture using an association phase in which emotionally neutral vs. positive-feedback photographs were paired with two alternative target colors, red vs. green. This was followed by a test phase requiring participants to search for a pop-out shape target in the presence or absence of an emotion-associated color. In Experiments 1 and 2, this color could only appear in a distractor, while in Experiment 3, it appeared in the target. Analyzing the standard, averaged RT measures, we found no significant valence association or valence-modulated attentional capture. However, correlational analyses revealed a positive relationship between individual participants’ color–valence preference during the association phase and their valence-based effect during the test phase. Moreover, most individuals favored red over green in the association phase, leading to marked color-related asymmetries in the average measures. Crucially, the presence of the valence-preferred color anywhere in the test display facilitated RTs. This effect persisted even when the color appeared in one of the distractors (Experiments 1 and 2), at variance with this distractor capturing attention. These findings suggest that task-irrelevant valence-preferred color signals were registered pre-attentively and boosted performance, likely by raising the general (non-spatial) alertness level. However, these signals were likely kept out of attentional-priority computation to prevent inadvertent attentional capture.

Do linguistic stimuli activate experiential colour traces related to the entities they refer to and, if so, under what circumstances?

The simulation view of language comprehension holds that lexical-semantic access prompts the re-enactment of sensorimotor experiences that regularly accompany word use. For the colour domain, this suggests that reading about a stop sign reactivates experiences involving the perception of the stop sign and hence experiences involving the colour red. However, it is still not clear what circumstances would limit reactivation of colour experiences during comprehension, if the activation takes place. To address this question, we varied in our study the conditions in which the target colour stimuli appeared. The experimental stimuli were individual words (Experiment (Exp.) 1, Exp. 7, 8) or sentences (Exp. 2-6) referring to objects with a typical colour of either green or red (e.g., cucumber or raspberry). Across experiments, we manipulated the presence of fillers (present or not), and whether fillers referred to objects with other colour (e.g., honey) or objects without any particular colour (e.g., car). The stimuli were presented along with two clickable "yes" and "no" buttons, one of which was red and the other green. Location and button colour varied from trial to trial. The tasks were lexical decision (Exp. 1, Exp. 7-8) and sensibility judgement (Exp. 2-6). We observed faster response times in the match vs mismatch condition in all word-based experiments, but only in those sentence-based experiments that did not have fillers. This suggests that comprehenders indeed reactivate colour experiences when processing linguistic stimuli referring to objects with a typical colour, but this activation seems to occur only under certain circumstances.

Design of Ground Target Based on RedEdge MX-Dual Multispectral Camera

Ground target plays an indispensable role in UAV near-earth remote sensing geometric positioning, geographic registration, correction and improvement of remote sensing image accuracy and accuracy. Traditional ground targets are markers with distinct features, shapes and textures, and their dimensions are usually fixed. The UAV can provide high-resolution multi-spectral data with multi-spectral camera, so the target resolution will change as the UAV height increases and the camera band increases, in some bands of the multi-spectral camera, there will be non-response, which will affect the accuracy of target recognition and positioning. Based on the color, material, size and shape of target, a set of targets suitable for target recognition and location of multi-spectral camera is designed in this paper. In order to judge whether the target performance meets the requirements, this paper verifies the positioning accuracy of the target and its response in each channel of the camera. It is proved that the target plane error is about 10mm at 20 ~ 100m altitude, and the height error is about 40mm, and it can respond in ten channels, it provides experience and ideas for the design and development of multi-spectral camera targets.

Matching target color in polyolefins by estimating pigment concentrations using a four-flux model.

In applications of computer color formulation where color stimuli are optically thick (e.g.,textiles, coatings, etc.), a simple single-constant or two-constant theory (e.g.,Kubelka-Munk model) would suffice. To accurately predict reflectance and transmittance of materials with optical thickness ranging from optically thin to optically thick (e.g.,plastics), mathematically complex radiative transfer theories (e.g.,many-flux models) have been recommended. A many-flux model can even predict color formulation involving special-effect pigments (e.g.,metallic, pearlescent, etc.), but implementation of such models is manyfold complicated. In the current study, applicability of a relatively simple Maheu-Letoulouzan-Gouesbet (MLG) four-flux radiative transfer model to optically varying pigmented polyolefins is thoroughly investigated. First, the MLG model was implemented to determine absorption and scattering coefficients of over 120 pigments where a new mean relative absolute spectral error (MRASE) between measured and calculated spectral reflectance and transmittance of the calibration samples was minimized as an objective function. Second, currently determined absorption and scattering coefficients were further validated by color recipe prediction of 350 historical product colors. Measured and predicted reflectance curves were compared in units of MRASE, CIEDE2000 color difference, metamerism index, root mean square error, and goodness-of-fit coefficient. Moreover, transmission matching was evaluated in units of percent difference between the required and predicted average transmittance. Results showed that with the current implementation of the MLG four-flux model, color recipes of at least 95% of the target colors can be predicted within the acceptability thresholds in units of different error metrics used in the study.

Proactive suppression can be applied to multiple salient distractors in visual search.

There is a growing body of research demonstrating that the capture of attention by a single salient distractor can be prevented via proactive suppression. In real-world contexts, there are often several distracting events that compete for attention, but it is entirely unknown whether multiple objects can be suppressed concurrently. We used behavioral and electrophysiological measures to investigate the existence and time course of multiple-item suppression. We employed search displays that contained either one or two uniquely colored distractors that differed in their salience (S+ and S-), or no such distractors. Search performance improved with the number of salient distractors, indicating that the suppression of multiple items reduced the effective display set size. This was also the case when the target color was no longer fully predictable, ruling out an alternative explanation in terms of attentional guidance by target templates. In an experiment where S+ and S- always appeared together in the same display, the PD component (a marker of proactive suppression) was triggered exclusively by the more salient distractor (S+), indicative of single-item suppression. However, when displays with one or both salient distractors were intermixed, a reliable PD component was also triggered by S-, even when it was accompanied by S+ in the same display. These results show that multiple concurrent salient signals can be proactively inhibited. They demonstrate that signal suppression processes can be adaptively employed to counteract visual distraction at different locations, in order to facilitate the attentional selection of relevant objects in crowded visual environments. (PsycInfo Database Record (c) 2023 APA, all rights reserved).