High-Fidelity Zero-Shot Texture Anomaly Localization Using Feature Correspondence Analysis

We propose a novel method for Zero-Shot Anomaly Localization that leverages a bidirectional mapping derived from the 1-dimensional Wasserstein Distance. The proposed approach allows pinpointing the anomalous regions in a texture with increased precision by aggregating the contribution of a pixel to the errors of all nearby patches. We validate our solution on several datasets and obtain more than a 40% reduction in error over the previous state of the art on the MVTec AD dataset in a zero-shot setting

Rendering Deformable Surface Reflectance Fields

Animation of photorealistic computer graphics models is an important goal for many applications. Image-based modeling has emerged as a promising approach to capture and visualize real-world objects. Animating image-based models, however, is still a largely unsolved problem. In this paper, we extend a popular image-based representation called surface reflectance field to animate and render deformable real-world objects under arbitrary illumination. Deforming the surface reflectance field is achieved by modifying the underlying impostor geometry. We augment the impostor by a local parameterization that allows the correct evaluation of acquired reflectance images, preserving the original light model on the deformed surface. We present a deferred shading scheme to handle the increased amount of data involved in shading the deformable surface reflectance field. We show animations of various objects that were acquired with 3D photography.Engineering and Applied Science

Tactile prints in colour: Studying the Visual Appearance of 2.5D Prints for Heritage Recreations

Printing applications for heritage recreation are a means to allow audiences to appreciate details and engage with cultural materials through closer interaction. A 2.5D print is a media suitable to incorporate visual and tactile qualities such as colour, low relief, textures and roughness. Designing a colour-accurate tactile print requires, nevertheless, anticipating how specific shapes and meso-geometries will affect the reflective properties of the surface, thus changing its appearance. Hence, this paper contributes to improve the understanding of the interaction between geometry and colour when deploying 2.5D prints so that tactile portable replicas can be easily produced. For this, we have produced a series of 2.5D printed patches with varying meso-textures, based on procedural noise functions, and measured their colour coordinates and glossiness. We aim to find a correlation between colour shift (expressed as lightness, chroma and ?E) and the scale and distribution of surface details

Image-based remapping of spatially-varying material appearance

BRDF models are ubiquitous tools for the representation of material appearance. However, there is now an astonishingly large number of different models in practical use. Both a lack of BRDF model standardisation across implementations found in different renderers, as well as the often semantically different capabilities of various models, have grown to be a major hindrance to the interchange of production assets between different rendering systems. Current attempts to solve this problem rely on manually finding visual similarities between models, or mathematical ones between their functional shapes, which requires access to the shader implementation, usually unavailable in commercial renderers. We present a method for automatic translation of material appearance between different BRDF models, which uses an image-based metric for appearance comparison, and that delegates the interaction with the model to the renderer. We analyse the performance of the method, both with respect to robustness and visual differences of the fits for multiple combinations of BRDF models. While it is effective for individual BRDFs, the computational cost does not scale well for spatially-varying BRDFs. Therefore, we further present a parametric regression scheme that approximates the shape of the transformation function and generates a reduced representation which evaluates instantly and without further interaction with the renderer. We present respective visual comparisons of the remapped SVBRDF models for commonly used renderers and shading models, and show that our approach is able to extrapolate transformed BRDF parameters better than other complex regression schemes

Mould Store: Exploring the Preservation of the former Spode Factory’s Post-Industrial Heritage through Digital Technologies

World renowned for its perfection of Bone China and underglaze blue printing techniques, the historic Spode Works in Stoke-on-Trent was one of the few ceramic manufactories in Britain to have operated continuously on its original site until the company ceased trading in 2008 1. In 1987 the legacy of this factory was assigned to the Spode Museum Trust, which currently houses many artefacts associated with the reproduction of the company’s vast design archive spanning over two centuries. Yet, prior to the factory’s closure there was an oversight not to accession the majority of factory’s historic moulds due to their perceived value and the sheer space required to house such material. As ‘by-products’ of ceramic manufacture, moulds are rarely valued or preserved for prosperity; the ‘finished’ ceramic artefact has always taken priority over those objects associated with labour of mass-production. Yet as tools that revolutionised the mechanical reproduction of decorative and functional artefacts, they can illuminate the evolution of important technological and stylistic changes in design and industry that remain relatively under-researched. As the former Spode site is currently in the process of regeneration and its buildings repurposed, only a small percentage of this material has been recommended for retention, with the remainder at risk of disposal. Apart from the time pressures from agencies wishing to regenerate the site, the challenges that exist for the potential documentation of such a sheer volume of material, led to a feasibility study being conducted by a team of interdisciplinary academics in July 2018. The aim of this study was to determine the most appropriate tools for the scanning process and devise an effective workflow system to minimise cost and time. A core sample of mould typologies, materials and technologies from c1850 onwards, were 3D scanned based upon moulds selected for retention by Stoke-on-Trent City Councils Archaeology Service. In the event of pending disposal, digitisation can preserve the shape of an artefact for prosperity, and if needs be, facilitate the physical reproduction of both negative and ‘positive’ ceramic shapes. This session will present work-in-progress, detailing the digital documentation of the ceramic moulds using 3D technologies. The final aim of the project is to archive a large selection of moulds typologies based upon factors such as ‘age, uniqueness, and value in terms of technological developments and the production process’. To further understanding into the complexities of industrial craft practices, the resultant dataset also aims to elucidate material and craft knowledge embodied within such objects. The re-imagining of this data through a contemporary artistic response, that integrates the use of digital technology and traditional know-how will also be discussed. This collaborative project is in conjunction with Staffordshire University, University of Brighton, University College London and Spode Museum Trust. 1 Spode branded wares continue to be made at the Portmeirion factory. Biographies Prof. Neil Brownsword, Professor of Ceramics, Staffordshire University Neil Brownsword is an artist, researcher and educator who holds Professorial positions in ceramics at Staffordshire University and University of Bergen. Brownsword’s practice examines the legacy of globalisation in relation to Stoke-on-Trent’s ceramic manufacturing sector, and the impact this has had upon people, place and traditional skills. His work is represented in public/private collections internationally, including the Victoria and Albert Museum, Korea Ceramic Foundation and the Yingee Ceramic Museum, Taiwan. In 2009 he was awarded the ‘One Off Award’ at the inaugural British Ceramic Biennial, and the Grand Prize at the Gyeonggi International Ceramic Biennale, South Korea in 2015. Prof. Tim Weyrich, Professor of Visual Computing, University College London Tim Weyrich is Professor of Visual Computing at the Department of Computer Science, University College London, Deputy Director of the UCL Centre for Digital Humanities and member of the Steering Board of the Eurographics Workshop on Graphics and Cultural Heritage amongst others. While a computer graphics and computer vision researcher by trade, Tim has a long-standing track record in putting his background in appearance modelling, 3D reconstruction and multi-modal imaging into the service of computational reconstruction and analysis of heritage objects, working with memory institutions and excavations around the world. Dr. Karina Rodriguez Echavarria, Principal Lecturer, University of Brighton Karina Rodriguez Echavarria is a Principal Lecturer at the School of Computing, Engineering and Mathematics at the University of Brighton and member of the Centre for Secure, Intelligent and Usable Systems. She has an interdisciplinary background in computer science and cultural heritage and leads various projects and initiatives in this interdisciplinary area. Her research interests include the development and application of computational technologies for the digitisation of objects and environments; as well as their physical reproduction using digital fabrication