Fast Color Space Transformations Using Minimax Approximations

Color space transformations are frequently used in image processing, graphics, and visualization applications. In many cases, these transformations are complex nonlinear functions, which prohibits their use in time-critical applications. In this paper, we present a new approach called Minimax Approximations for Color-space Transformations (MACT).We demonstrate MACT on three commonly used color space transformations. Extensive experiments on a large and diverse image set and comparisons with well-known multidimensional lookup table interpolation methods show that MACT achieves an excellent balance among four criteria: ease of implementation, memory usage, accuracy, and computational speed

Unrestricted multivariate medians for adaptive filtering of color images

Reduction of impulse noise in color images is a fundamental task in the image processing field. A number of approaches have been proposed to solve this problem in literature, and many of them rely on some multivariate median computed on a relevant image window. However, little attention has been paid to the comparative assessment of the distinct medians that can be used for this purpose. In this paper we carry out such a study, and its conclusions lead us to design a new image denoising procedure. Quantitative and qualitative results are shown, which demonstrate the advantages of our method in terms of noise reduction, detail preservation and stability with respect to a selection of well-known proposals.Presentado en el IX Workshop Computación Gráfica, Imágenes y Visualización (WCGIV)Red de Universidades con Carreras en Informática (RedUNCI

Unrestricted multivariate medians for adaptive filtering of color images

Reduction of impulse noise in color images is a fundamental task in the image processing field. A number of approaches have been proposed to solve this problem in literature, and many of them rely on some multivariate median computed on a relevant image window. However, little attention has been paid to the comparative assessment of the distinct medians that can be used for this purpose. In this paper we carry out such a study, and its conclusions lead us to design a new image denoising procedure. Quantitative and qualitative results are shown, which demonstrate the advantages of our method in terms of noise reduction, detail preservation and stability with respect to a selection of well-known proposals.Presentado en el IX Workshop Computación Gráfica, Imágenes y Visualización (WCGIV)Red de Universidades con Carreras en Informática (RedUNCI

Eliminação de Ruído Impulsivo Usando um Filtro Mediano Seletivo e Difusão Isotrópica

Neste trabalho apresenta-se um algoritmo combinando-se uma modificação do filtro mediano padrão, com base no detector de ruído impulsivo proposto por Chen, Yang e Cao, com um processo de difusão isotrópica para remoção de ruído sal e pimenta. Para eliminar ruído impulsivo em imagens coloridas, a ideia é aplicar o algoritmo separadamente em cada canal de cor. Os experimentos realizados indicam que o método proposto apresenta-se como um filtro robusto para restauração de imagens com grandes densidades de ruído

Polymers for Advanced Laundry Applications

Dye transfer in the laundry occurs whereby dye molecules are removed from darker garments and deposit onto lighter garments. This results in greying and discolouration of the lighter coloured garments, shortening the lifespan of the clothing, or resulting in the need to separate washes into ‘light’ and ‘dark’ laundry loads. Therefore, dye transfer inhibitors are added to laundry detergent formulations to prevent dye transfer and preserve the appearance of consumer garments. This thesis explores a variety of means to combat dye transfer, including biopolymeric particles and synthetic polymers which act in a variety of ways to preserve garment appearance. Firstly, biopolymeric hydrogels were investigated for their ability to adsorb dyes from aqueous solution. Chitosan hydrogels were found to be particularly effective, owing to the presence of free primary amine groups which may electrostatically attract anionic dye molecules. Therefore, microsphere biopolymer particles were explored for their ability to encapsulate dye molecules in simulated laundry wash loads to prevent dye transfer. It was found that dye transfer was reduced in the presence of anionic particles, suggesting the particles deposit onto the fabric and repel dye deposition. Polymers which were designed to interact with the fabric and repel dye deposition were then researched, and methoxy-poly(ethylene glycol)-co-polyesters were found to be effective at preventing the deposition of indigo dye, alongside methoxy-poly(ethylene glycol)-co-poly(amino acid)s. Polymers based on gamma-benzyl-L-glutamate were found to be most effective at preventing the deposition of indigo. The synthetic polymers therefore provide a large amount of scope for future detergent applications of dye transfer inhibition polymeric agents

Aplicació de mètriques fuzzy en la millora computacional d'algorismes de filtratge d'imatges en color

El filtrado de imágenes es una tarea fundamental para la mayoría de los sistemas de visión por computador cuando las imágenes se usan para análisis automático o, incluso, para inspección humana. De hecho, la presencia de ruido en una imagen puede ser un grave impedimento para las sucesivas tareas de procesamiento de imágenes como, por ejemplo, la detección de bordes o el reconocimiento de patrones u objetos y, por lo tanto, el ruido debe ser reducido. Del mismo modo, el aumento de la resolución y el tamaño de las imágenes nos conduce a requerimientos computacionales más altos, los cuales hemos de intentar rebajar sobre todo para aplicaciones en tiempo real o similares. En los últimos años el interés por utilizar imágenes en color se ha visto incrementado de forma significativa en una gran variedad de aplicaciones. Es por esto que el filtrado de imágenes en color se ha convertido en un área de investigación interesante. Se ha observado ampliamente que las imágenes en color deben ser procesadas teniendo en cuenta la correlación existente entre los distintos canales de color de la imagen. En este sentido, la solución probablemente más conocida y estudiada es el enfoque vectorial. Las primeras soluciones que proponen técnicas de filtrado vectorial, son las conocidas técnicas del filtro de mediana vectorial (VMF) o el filtro direccional vectorial (VDF). Desafortunadamente, estas técnicas no se adaptan a las características locales de la imagen, lo que implica que habitualmente los bordes y detalles de las imágenes se emborronan y pierden calidad. A fin de solventar este problema, se han propuesto recientemente varios filtros vectoriales adaptativos, entre los que destacan las técnicas de peer group. En los últimos años ha aparecido la teoría de los denominados conjuntos fuzzy, borrosos o difusos (lógica, métricas y topologías), que se ha demostrado es una herramienta adecuada para el filtrado de imágenes. En la presente Tesis Doctoral las metas principales son: (i) el esCamarena Estruch, JG. (2009). Aplicació de mètriques fuzzy en la millora computacional d'algorismes de filtratge d'imatges en color [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/4339Palanci

Cleaning principles in automatic dishwashers

Cleaning inside automatic dishwashers (ADWs) represents an example of a ‘black box’ problem. The description of the phenomena occurring during a typical wash cycle is not currently well known. This thesis aims to illustrate and expand the in-depth knowledge required to better understand the wash process by analysing the different mechanical and chemical factors involved as well as the interactions between them. Online measurements techniques (Positron Emission Particle Tracking, scanning Fluid Dynamic Gauge or Image Analysis) were combined with statistical and numerical modelling to investigate the evolution over time of the cleaning system

Localised rank-ordered differences vector filter for suppression of high-density impulse noise in colour images

This research presents a complete study of a new alternating vector filter for the removal of impulsive noise in colour images. The method is based on an impulsive noise detector for greyscale images that has been adapted in a localised manner using geometric information for processing colour images. Based on this statistic, a filtering scheme alternating between the identity and a non-linear vector filter is proposed. A geometric and experimental study was performed to obtain the optimal filter design. Experimental studies show that the proposed technique is simple, easy to implement, robust to noise, and outperforms the classic vector filters, as well as more recent filters.Roig, B.; Estruch, V. (2016). Localised rank-ordered differences vector filter for suppression of high-density impulse noise in colour images. IET Image Processing. 10(1):24-33. doi:10.1049/iet-ipr.2014.0838S2433101Astola, J., Haavisto, P., & Neuvo, Y. (1990). Vector median filters. 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IEEE Signal Processing Letters, 14(6), 397-400. doi:10.1109/lsp.2006.887840Lin, T.-C., & Yu, P.-T. (2004). Partition fuzzy median filter based on fuzzy rules for image restoration. Fuzzy Sets and Systems, 147(1), 75-97. doi:10.1016/s0165-0114(03)00209-4Schulte, S., De Witte, V., Nachtegael, M., Van der Weken, D., & Kerre, E. E. (2007). Fuzzy random impulse noise reduction method. Fuzzy Sets and Systems, 158(3), 270-283. doi:10.1016/j.fss.2006.10.010Lukac, R., Plataniotis, K. N., Venetsanopoulos, A. N., & Smolka, B. (2005). A Statistically-Switched Adaptive Vector Median Filter. Journal of Intelligent and Robotic Systems, 42(4), 361-391. doi:10.1007/s10846-005-1730-2Srinivasan, K. S., & Ebenezer, D. (2007). A New Fast and Efficient Decision-Based Algorithm for Removal of High-Density Impulse Noises. IEEE Signal Processing Letters, 14(3), 189-192. doi:10.1109/lsp.2006.884018Chan, R. H., Chung-Wa, & Nikolova, M. (2005). Salt-and-pepper noise removal by median-type noise detectors and detail-preserving regularization. IEEE Transactions on Image Processing, 14(10), 1479-1485. doi:10.1109/tip.2005.852196Gallegos-Funes, F. J., & Ponomaryov, V. I. (2004). Real-time image filtering scheme based on robust estimators in presence of impulsive noise. Real-Time Imaging, 10(2), 69-80. doi:10.1016/j.rti.2004.02.002Lukac, R. (2004). Adaptive Color Image Filtering Based on Center-Weighted Vector Directional Filters. Multidimensional Systems and Signal Processing, 15(2), 169-196. doi:10.1023/b:mult.0000017024.66297.a0Morillas, S., Gregori, V., Peris-Fajarnés, G., & Latorre, P. (2005). A fast impulsive noise color image filter using fuzzy metrics. Real-Time Imaging, 11(5-6), 417-428. doi:10.1016/j.rti.2005.06.007Smolka, B., Lukac, R., Chydzinski, A., Plataniotis, K. N., & Wojciechowski, W. (2003). Fast adaptive similarity based impulsive noise reduction filter. Real-Time Imaging, 9(4), 261-276. doi:10.1016/j.rti.2003.09.015Smolka, B., & Chydzinski, A. (2005). Fast detection and impulsive noise removal in color images. Real-Time Imaging, 11(5-6), 389-402. doi:10.1016/j.rti.2005.07.003Dong, Y., & Xu, S. (2007). A New Directional Weighted Median Filter for Removal of Random-Valued Impulse Noise. IEEE Signal Processing Letters, 14(3), 193-196. doi:10.1109/lsp.2006.884014Jin, L., & Li, D. (2007). A switching vector median filter based on the CIELAB color space for color image restoration. Signal Processing, 87(6), 1345-1354. doi:10.1016/j.sigpro.2006.11.008Yuan, S.-Q., & Tan, Y.-H. (2006). Impulse noise removal by a global–local noise detector and adaptive median filter. Signal Processing, 86(8), 2123-2128. doi:10.1016/j.sigpro.2006.01.009Garnett, R., Huegerich, T., Chui, C., & Wenjie He. (2005). A universal noise removal algorithm with an impulse detector. IEEE Transactions on Image Processing, 14(11), 1747-1754. doi:10.1109/tip.2005.857261Yuzhong Shen, & Barner, K. E. (2006). Fast adaptive optimization of weighted vector median filters. IEEE Transactions on Signal Processing, 54(7), 2497-2510. doi:10.1109/tsp.2006.874028Yao Nie, & Barner, K. E. (2006). The fuzzy transformation and its applications in image processing. IEEE Transactions on Image Processing, 15(4), 910-927. doi:10.1109/tip.2005.863111Yuksel, M. E. (2006). A hybrid neuro-fuzzy filter for edge preserving restoration of images corrupted by impulse noise. IEEE Transactions on Image Processing, 15(4), 928-936. doi:10.1109/tip.2005.863941Hanji, G., & Latte, M. (2012). Detail Preserving Fast Median Based Filter. Journal of Advanced Computer Science & Technology, 1(4). doi:10.14419/jacst.v1i4.248Ibrahim, H., Pik Kong, N., & Ng, T. (2008). Simple adaptive median filter for the removal of impulse noise from highly corrupted images. 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