Global Color Research Articles

Detection of Iris Presentation Attacks Using Feature Fusion of Thepade's Sorted Block Truncation Coding with Gray-Level Co-Occurrence Matrix Features.

Iris biometric detection provides contactless authentication, preventing the spread of COVID-19-like contagious diseases. However, these systems are prone to spoofing attacks attempted with the help of contact lenses, replayed video, and print attacks, making them vulnerable and unsafe. This paper proposes the iris liveness detection (ILD) method to mitigate spoofing attacks, taking global-level features of Thepade’s sorted block truncation coding (TSBTC) and local-level features of the gray-level co-occurrence matrix (GLCM) of the iris image. Thepade’s SBTC extracts global color texture content as features, and GLCM extracts local fine-texture details. The fusion of global and local content presentation may help distinguish between live and non-live iris samples. The fusion of Thepade’s SBTC with GLCM features is considered in experimental validations of the proposed method. The features are used to train nine assorted machine learning classifiers, including naïve Bayes (NB), decision tree (J48), support vector machine (SVM), random forest (RF), multilayer perceptron (MLP), and ensembles (SVM + RF + NB, SVM + RF + RT, RF + SVM + MLP, J48 + RF + MLP) for ILD. Accuracy, precision, recall, and F-measure are used to evaluate the performance of the projected ILD variants. The experimentation was carried out on four standard benchmark datasets, and our proposed model showed improved results with the feature fusion approach. The proposed fusion approach gave 99.68% accuracy using the RF + J48 + MLP ensemble of classifiers, immediately followed by the RF algorithm, which gave 95.57%. The better capability of iris liveness detection will improve human–computer interaction and security in the cyber-physical space by improving person validation.

Rethinking Gender, Citizenship, and War: Female Enemy Aliens in Australia during World War I

ABSTRACT Enemy aliens were undesirable migrants in Australia during World War I, right? Yet enemy alien women who sought naturalisation were largely successful. Using the concept of ‘desire’, this article uses quantitative and qualitative material from women’s naturalisation applications to consider why women applied and subsequent state decision-making. The narratives of applicants and administrators reflect wider negotiations over different types of citizenship, where women could challenge their very labelling as enemy aliens, or employ highly gendered notions of vulnerability and respectability. Particular groups were treated favourably, revealing practices which challenge existing historiography about how migration and citizenship laws worked throughout the British empire, especially concerning race and denaturalised women. This is part of a wider need to reassess the relationship between migration law and practice, especially the role of gender and the use of executive privilege. While important to recognise the overlapping push for a ‘global color line’ in creating the system which developed within the British empire, it was less a legal system and more of a constant negotiation between different actors, based on laws that were often imprecise. In this case they gave space for enemy alien women to circumvent the legislative restrictions on their naturalisation, despite the politics of war.

Reference-guided structure-aware deep sketch colorization for cartoons

Digital cartoon production requires extensive manual labor to colorize sketches with visually pleasant color composition and color shading. During colorization, the artist usually takes an existing cartoon image as color guidance, particularly when colorizing related characters or an animation sequence. Reference-guided colorization is more intuitive than colorization with other hints, such as color points or scribbles, or text-based hints. Unfortunately, reference-guided colorization is challenging since the style of the colorized image should match the style of the reference image in terms of both global color composition and local color shading. In this paper, we propose a novel learning-based framework which colorizes a sketch based on a color style feature extracted from a reference color image. Our framework contains a color style extractor to extract the color feature from a color image, a colorization network to generate multi-scale output images by combining a sketch and a color feature, and a multi-scale discriminator to improve the reality of the output image. Extensive qualitative and quantitative evaluations show that our method outperforms existing methods, providing both superior visual quality and style reference consistency in the task of reference-based colorization.

Evaluation of the operational Chlorophyll-a product from global ocean colour sensors in the coastal waters, south-eastern Arabian Sea

The present study aims to address the effect of spatial resolution and retrieval algorithms on the performance of operational chlorophyll-a (chl-a) product from different sensors. To meet the objective, chl-a product at different spatial resolutions derived from MODIS, SNPP-VIIRS, OC-CCI, and Sentinel-3A OLCI were compared with in-situ measurements of the coastal waters of Karnataka, south-eastern Arabian Sea and errors were quantified using statistical criteria. MODIS-derived chl-a concentrations at 4 km tends to overestimate in the nearshore waters as shown by a high mean relative percentage difference (MRPD) of 77.09%, and a low coefficient of determination (R2) of 0.35. A significant improvement was seen for MODIS 1 km chl-a product, (R2 = 0.64, MRPD = 22.30%) and Mean Absolute Percentage Deviation (MAPD) = 47.08%. Validation of SNPP-VIIRS derived chl-a of 4 km with in-situ measurements showed moderate correlation (R2 = 0.54, MAPD = 49.21%), whereas 1 km SNPP-VIIRS showed substantially better result than 4 km with majority of data points aggregated along the 1:1 line (R2 = 0.86, MAPD = 43.66%, MRPD = 20.97%). Chlorophyll-a product at original resolution (750 m) showed less error than 4 km and 1 km resolution (MAPD = 39.18%, R2 = 0.75, MRPD = 10.875%). In contrast, OC-CCI underestimated field measured chl-a concentrations as indicated by MRPD (-36.72%), with moderate R2 = 0.58. All 4 km data showed poor results than higher spatial resolution data. Sentinel-3A OLCI 300 m full-resolution (FR) derived chl-a, showed good agreement with sea-truth data (R2 = 0.80, MAPD = 33.07%, and MRPD = 23.89%), whereas Sentinel-3A reduced-resolution (RR-1.2 km) exhibited slight overestimation (MRPD = 28.43%, MAPD = 39.88%, R2 = 0.78) than Sentinel-3A(FR). Comparison of operational chl-a product from OC-CCI, MODIS, SNPP-VIIRS, and Sentinel-3A OLCI illustrated that Sentinel-3A OLCI performed best in coastal waters of Karnataka indicating the importance of higher spatial resolution and neural network-based algorithms.

Disentangled and controllable sketch creation based on disentangling the structure and color enhancement

Existing sketch-based image processing methods include sketch recognition, sketch synthesis and sketch-based image retrieval. For sketch creation, a meaningful task is proposed namely disentangled and controllable sketch creation (DCSC) based on disentangling the structure and color enhancement. Specifically, as the first subtask, sketch structure enhancement (SSE) is used to enhance a non-professional sketch (NPS) and obtain a professional sketch (PS), which is a process denoted as NPS2PS. A data set named SketchMan is first provided, consisting of NPSs and PSs with various postures in different scenes. SSE is trained as a conditional image-to-image translation problem, and there are three models: direct sketch-to-sketch (SS), grayscale guided SS and contour guided SS. Multiple IOU metrics are proposed based on Corner Point Map (CPM), Straight Line Map (SLM) and Segmented Area Map (SAM). As the second subtask, sketch color enhancement (SCE) is trained as a two-stage framework containing a topology enhancement network (TE-Net) that maps a sketch to the corresponding grayscale domain and a color injection network (CI-Net) that injects the global color feature to the AdaIN residual blocks to perform adaptive sketch colorization. The TE-Net and CI-Net disentangle the topological and color features to perform more controllable and diverse SCE results. Experimental results demonstrate that our proposed methods are effective to address the challenging and meaningful DCSC task compared with other state-of-the-art methods.

Reflections on Ben Okri, Goenawan Mohamad, and the 2020 Global Uprisings

The global Black Lives Matter uprisings against police violence prompted by Floyd’s murder were connected to a longer history of transnational Black struggles. As Ben Okri and Goenawan Mohamad and others have suggested, the civil rights and Black Power movements from the 1950s to the 1970s were not confined to US terrain; they were part of a global conjuncture. Protests throughout the Western world highlighted the blood-soaked record of the global color line, coalescing around demands for the official repudiation of the continuing legacies of racial oppression, enslavement, segregation, and empire. In the United States, the Black Lives Matter movement transformed the public conversation in the US about police violence. Caught in the act, Derek Chauvin seemed untroubled at being recorded by a courageous 17-year-old Darnella Frazier. We do not know what he was thinking, but still one recalls those members of lynch mobs posing for photographs during the Jim Crow era. Convinced that he would not be held accountable by a system of state-sanctioned violence, Chauvin appears to have believed that his use of deadly force was justifiable, just as similar extrajudicial killings by police officers of Black people have been upheld by juries and the criminal–legal system. BLM linked the crisis of oppressive policing to longstanding racial inequities in health, housing, employment, and income while insisting on the sanctity of the lives of Black poor, queer, and transgender persons, and persons living with disabilities. Republican-authored laws seeking to wrest autocratic control of education by criminalizing the teaching of race in US history are a craven response to the ways that the global reckoning on racism in 2020 has altered the US political landscape.

Titania-silica Composite with Photocatalytic Properties and Its Application on Brazilian Granite and Sandstone

ABSTRACT The aim of the study described in this article was to evaluate a product containing titania (titanium dioxide, TiO2) applied on stones — particularly two types used at Brazilian stone-built heritage sites — that have been exposed to weathering and anthropogenic activities. This product was prepared by producing a suspension of TiO2 at two concentrations (1% and 4% w/v) with tetraethyl orthosilicate (TEOS) in the presence of n-octylamine as surfactant. The characteristics of the TiO2 were then observed by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface-area measurements, particle-size distribution analysis (CILAS) and X-ray diffraction. After applying the TiO2-TEOS composite, the stones were examined for contact angle, spectrophotometry, sorptivity, thermal shock resistance, and UV-radiation resistance. The product proved ineffective on Itararé sandstone, mainly due to its mineralogical components, as the product does not adhere to quartz. When applied on Itaquera granite, the 1% TiO2 (w/v) concentration proved to be an appropriate treatment, as it demonstrated better thermal shock resistance, photocatalytic activity, porosity maintenance, and global colour when compared to the 4% concentration.

Triton: Topography and Geology of a Probable Ocean World with Comparison to Pluto and Charon

The topography of Neptune’s large icy moon Triton could reveal important clues to its internal evolution, but has been difficult to determine. New global digital color maps for Triton have been produced as well as topographic data for <40% of the surface using stereogrammetry and photoclinometry. Triton is most likely a captured Kuiper Belt dwarf planet, similar though slightly larger in size and density to Pluto, and a likely ocean moon that exhibited plume activity during Voyager 2′s visit in 1989. No surface features or regional deviations of greater than ±1 km amplitude are found. Volatile ices in the southern terrains may take the form of extended lobate deposits 300–500 km across as well as dispersed bright materials that appear to embay local topography. Limb hazes may correlate with these deposits, indicating possible surface–atmosphere exchange. Triton’s topography contrasts with high relief up to 6 km observed by New Horizons on Pluto. Low relief of (cryo)volcanic features on Triton contrasts with high-standing massifs on Pluto, implying different viscosity materials. Solid-state convection occurs on both and at similar horizontal scales but in very different materials. Triton’s low relief is consistent with evolution of an ice shell subjected to high heat flow levels and may strengthen the case of an internal ocean on this active body.

Underwater image restoration via depth map and illumination estimation based on a single image.

For the enhancement process of underwater images taken in various water types, previous methods employ the simple image formation model, thus obtaining poor restoration results. Recently, a revised underwater image formation model (i.e., the Akkaynak-Treibitz model) has shown better robustness in underwater image restoration, but has drawn little attention due to its complexity. Herein, we develop a dehazing method utilizing the revised model, which depends on the scene depth map and a color correction method to eliminate color distortion. Specifically, we first design an underwater image depth estimation method to create the depth map. Subsequently, according to the depth value of each pixel, the backscatter is estimated and removed by the channel based on the revised model. Furthermore, we propose a color correction approach to adjust the global color distribution of the image automatically. Our method only uses a single underwater image as input to eliminate lightwave absorption and scattering influence. Compared with state-of-the-art methods, both subjective and objective experimental results show that our approach can be applied to various real-world underwater scenes and has better contrast and color.

Kojo Koram (Ed.): The War on Drugs and the Global Color Line

Kojo Koram (Ed.): The War on Drugs and the Global Color Line

Seasonal bias in global ocean color observations.

In this study, we identify a seasonal bias in the ocean color satellite-derived remote sensing reflectances (Rrs(λ);sr-1) at the ocean color validation site, Marine Optical BuoY. The seasonal bias in Rrs(λ) is present to varying degrees in all ocean color satellites examined, including the Visible Infrared Imaging Radiometer Suite, Sea-Viewing Wide Field-of-View Sensor, and Moderate Resolution Imaging Spectrometer. The relative bias in Rrs has spectral dependence. Products derived from Rrs(λ) are affected by the bias to varying degrees, with particulate backscattering varying up to 50% over a year, chlorophyll varying up to 25% over a year, and absorption from phytoplankton or dissolved material varying by up to 15%. The propagation of Rrs(λ) bias into derived products is broadly confirmed on regional and global scales using Argo floats and data from the cloud-aerosol lidar with orthogonal polarization instrument aboard the cloud-aerosol lidar and infrared pathfinder satellite. The artifactual seasonality in ocean color is prominent in areas of low biomass (i.e., subtropical gyres) and is not easily discerned in areas of high biomass. While we have eliminated several candidates that could cause the biases in Rrs(λ), there are still outstanding questions regarding potential contributions from atmospheric corrections. Specifically, we provide evidence that the aquatic bidirectional reflectance distribution function may in part cause the observed seasonal bias, but this does not preclude an additional effect of the aerosol estimation. Our investigation highlights the contributions that atmospheric correction schemes can make in introducing biases in Rrs(λ), and we recommend more simulations to discern these influence Rrs(λ) biases. Community efforts are needed to find the root cause of the seasonal bias because all past, present, and future data are, or will be, affected until a solution is implemented.

Quaternion fractional-order color orthogonal moment-based image representation and recognition

Inspired by quaternion algebra and the idea of fractional-order transformation, we propose a new set of quaternion fractional-order generalized Laguerre orthogonal moments (QFr-GLMs) based on fractional-order generalized Laguerre polynomials. Firstly, the proposed QFr-GLMs are directly constructed in Cartesian coordinate space, avoiding the need for conversion between Cartesian and polar coordinates; therefore, they are better image descriptors than circularly orthogonal moments constructed in polar coordinates. Moreover, unlike the latest Zernike moments based on quaternion and fractional-order transformations, which extract only the global features from color images, our proposed QFr-GLMs can extract both the global and local color features. This paper also derives a new set of invariant color-image descriptors by QFr-GLMs, enabling geometric-invariant pattern recognition in color images. Finally, the performances of our proposed QFr-GLMs and moment invariants were evaluated in simulation experiments of correlated color images. Both theoretical analysis and experimental results demonstrate the value of the proposed QFr-GLMs and their geometric invariants in the representation and recognition of color images.

Ultraviolet remote sensing of marine oil spills: a new approach of Haiyang-1C satellite.

Haiyang-1C (HY-1C) is the first operational ocean color satellite of China, which is intended to obtain daily global ocean color data. The Ultraviolet Imager (UVI) onboard provides a potential novel detector for the detection of marine oil spills. Although airborne UV sensors have shown great efficiency for the detection of spilled oils, the capability of spaceborne UV sensor is not yet clear. In this study, we designed a ground-based experiment to interpret the UV characteristics of various weathered oils, and found that very thin oil films are quite sensitive to the UV radiation due to the surface interference light. Moreover, by comparing spaceborne and airborne UV images of spilled oils collected from HY-1C UVI and AVIRIS, the scale effect of ultraviolet remote sensing has been interpreted clearly. The interference light and sunglint reflection play different roles in the imaging process of spilled oils, leading them to appear radical different features (brighter or darker than the background oil-free seawater) in ground, airborne and spaceborne observation, which deserves further research. Ultraviolet remote sensing, therefore, can work as a new approach and improve the detection and monitoring of marine oil spills.

Priming Effect of Colour on Aiding the Attentional Reorientation in Sequential Presentations of Temporal Data Visualization: Evidence From Eye-Tracking

Abstract In the present study, we focus on the priming effect of colour on mitigating the attentional reorientation cost, which is led by re-constructing the frame of reference for attention shift and visual search in sequential presentations of temporal data visualization. The study involves two experiments using complementary recordings of behavioural performance and eye-tracking events. Two aspects of colour primes are highlighted: the prime validity and the colour perceptual accessibility. A task paradigm integrating the feature search and keeping-track task was adopted in our experiments. In Experiment 1 (with a group of 16 participants), we confirmed the colour priming effect by comparing the priming condition to the neutral baseline. Furthermore, global colours that are with high perceptual accessibility generated more evident priming effects than local colours. However, more interferences in misguiding the attention to task-irrelevant regions were found when the global primes were invalid. In Experiment 2 (with another group of 15 participants), we verify the finding in Experiment 1 that global colours produced more pronounced priming effects in alleviating the attentional reorientation cost by comparing two groups of real-world visualizations with either global or local colours as the prime. Large saccades were initiated much earlier, and the search efficiency got improved when provided with global colours. We conjecture that the facilitatory effect from global colours may stem from its benefit on the pre-attentive processing of the search field. The research findings provide evidence for utilizing colours as the primes in mitigating the attentional reorientation cost and accelerating visual search in sequential presentations.

Global land mask for satellite ocean color remote sensing

We develop a methodology to derive a global medium resolution (250 m) land mask from several existing data sources. In particular, a number of improved land mask data sets have been developed from satellite measurements recently, though some artifacts and omissions still remain. We show how combining global land mask data from multiple independent data sources can decrease the frequency of artifacts, and improve the data consistency and quality. We use the ocean color product imagery derived from measurements of the Visible Infrared Imaging Radiometer Suite (VIIRS) onboard the Suomi National Polar-orbiting Partnership (SNPP) to evaluate and validate the new global land mask implemented in the Multi-Sensor Level-1 to Level-2 (MSL12) ocean color data processing system, and demonstrate the improvements in the derived global ocean color data coverage. Results show that when using the new proposed land mask the accuracy of global ocean color data coverage is significantly improved over coastal and inland waters. The new land mask more accurately represents the current global land coverage status, providing more complete and consistent global land/water coverage data set for ocean color remote sensing and for various other satellite Earth observing applications.

Effect of Pretreatment with Low-Frequency Ultrasound on Quality Parameters in Gulupa (Passiflora edulis Sims) Pulp

The Gulupa (Passiflora edulis f. edulis Sims) is an expression of South America’s tropics’ biodiversity, and a source of B vitamins and amino acids. It is a climacteric export fruit for which it is necessary to incorporate emerging technologies for its conservation and transport. This work investigated the effect of ultrasound on gulupa pulp and verified the stability of the characters of interest in the shelf life of 20 days. Six treatments and a control sample were used, evaluated in triplicate, and varied in frequency (30 and 40 kHz) with an exposure time of 10, 20, and 30 min. A statistical analysis of unidirectional variances and Dunnett’s test was used. It was found that the ultrasound treatments did not affect the pH or the titratable acidity. Soluble solid results presented a significant increase (p < 0.05) (from 13.4 to 14.8% w/v) in the antioxidant capacity (from 1.13 to 1.54 µmol Trolox Equivalent (TE)/g by the ABTS•+ (2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) Cationic Radical Assay and from 3.3 to 3.7 µmol TE/g by the DPPH· (2,2-diphenyl-1-picrilhydrazil) Radical Scavenging Assay). During the shelf life, ascorbic acid was the parameter that varied most (p < 0.05). It decreased from 42.7 to 21.6 mg ascorbic acid/100 g of pulp in the control sample. However, a smaller decrease was observed (23.8–24.5 mg ascorbic acid/100 g of pulp) in the 40 kHz treatments. The smallest global color difference (ΔE) for the control was found in the 40 kHz treatment at 30 min through the entire shelf life (day 0 to 20). Ultrasound treatment offers a new strategy to improve and extend the shelf life of chilled gulupa pulp.

W.E.B. Du Bois în studiile contemporane: conștiința dublă și modernitatea rasializată

This article outlines W.E.B. Du Bois’s general sociological theory and literary activity in connection to the recent study of Jose Itzigsohn and Karida L. Brown, The Sociology of W.E.B. Du Bois. Racialized Modernity and the Global Color Line. It describes the role of Double Consciousness and Racialized Modernity within postcolonial and decolonial theory and explains how postcolonial Romanian studies have engaged with postcolonial theory by avoiding these concepts.

On W.E.B. Du Bois, Double Consciousness, and Racialized Modernity. An Interview with José Itzigsohn

The February issue of Transilvania journal hosts an interview with professor José Itzigsohn focusing on his activity within the field of sociology and his latest book with Karida L. Brown, on The Sociology of W. E. B. Du Bois. Racialized Modernity and the Global Color Line (New York University Press, 2020). It delves into Du Boisian sociology, “double consciousness” and racialized modernity, alongside contemporary decolonial perspectives and new studies and researchers in the field.

Confinement and the global SU(3) color symmetry * *Supported by the Strategic Priority Research Program of Chinese Academy of Sciences (XDB34030302) and the National Natural Science Foundation of China (NNSFC) (11935017, 11575196, 12070131001) (CRC 110 by DFG and NSFC)

The global color symmetry and its physical consequences are discussed. The Nöther current is actually governed by the conserved matter current of color charges if the color field generated by this charge is properly polarized. The color field strength of a charge can have a uniform part due to the nontrivial QCD vacuum field and the nonzero gluon condensate, which implies that the self-energy of a system with a net color charge is infinite and, therefore, cannot exist as a free state. This is precisely what color confinement means. Accordingly, the Cornell type potential with the feature of Casimir scaling is derived for a color singlet system composed of a static color charge and an anti-charge. The uniform color field also implies that a hadron has a minimal size and minimal energy. Furthermore, the global color symmetry requires that the minimal irreducible color singlet systems can only be , , , , , , , etc., therefore a multi-quark system can only exist as a molecular configuration if there are no other binding mechanisms.

W-Tree Indexing For Fast Visual Word Generation

In image retrieval and visual identification, the bag-of-visual-words model has been extensively employed. The process of creating visual words—adding visual words to the associated local characteristics in a high-dimensional space—takes the longest to complete in order to acquire this representation. In order to save time, structures constructed around multi-branch trees & forests have recently been implemented. However, without a lot of backtracking, these approaches are unable to work well. In this study, we demonstrate that the lengthy process of visual word formation may be greatly sped up while keeping accuracy by taking into account the spatial correlation of local variables. We may create a co-occurrence table for each visual word in a huge data collection since some visual terms commonly co-occur with specific structures. We are able to allocate a probabilistic weight to each node of an index structure (for example, a KD-tree and a K-means tree) by associating each visual word with a probability in accordance with the corresponding co-occurrence table. This allows us to re-direct the searching path to be nearby to its global optimum within a minimal number of backtrackings. On the Oxford data set, we carefully examine the proposed scheme by contrasting it with the fast library for approximative nearest neighbours along with the random KD-trees. Extensive experimental findings point to the new scheme's effectiveness and efficiency. FeatureMatch, a generalised approximate nearest-neighbor field (ANNF) calculation framework connecting a source and target picture, is the solution we provide in this study. The suggested approach can calculate ANNF maps between any picture pairings, including unrelated ones. By using the proper spatial-range transformations, this generalisation is accomplished. Global colour adaptation is used on the source picture as a range transform to calculate ANNF maps. Low-dimensional characteristics are employed to approximate the image patches from the pair of photos, and KD-tree and ANNF estimation are combined. Based on picture coherency and spatial transformations, this ANNF map is further enhanced. We can now handle a broader spectrum of vision applications thanks to the suggested generalisation, which we couldn't previously manage with the ANNF framework.