Search Results (27)

Processing ancient text images presents significant challenges due to severe visual degradation, missing glyph structures, and various types of noise caused by aging. These issues are particularly prominent in Chinese historical documents and stone inscriptions, where diverse writing styles, multi-angle capturing, uneven lighting, and low contrast further hinder the performance of traditional OCR techniques. In this paper, we propose a unified neural framework, UniText, for the detection, recognition, and glyph restoration of Chinese characters in images of historical documents and inscriptions. UniText operates at the character level and processes full-page inputs, making it robust to multi-scale, multi-oriented, and noise-corrupted text. The model adopts a multi-task architecture that integrates spatial localization, semantic recognition, and visual restoration through stroke-aware supervision and multi-scale feature aggregation. Experimental results on our curated dataset of ancient Chinese texts demonstrate that UniText achieves a competitive performance in detection and recognition while producing visually faithful restorations under challenging conditions. This work provides a technically scalable and generalizable framework for image-based document analysis, with potential applications in historical document processing, digital archiving, and broader tasks in text image understanding. Full article

Over the last decades, plenty of ancient manuscripts have been digitized all over the world, and particularly in Europe. The fruition of these huge digital archives is often limited by the bleed-through effect due to the acid nature of the inks used, resulting in very noisy images. Several authors have recently worked on bleed-through removal, using different approaches. With the aim of developing a bleed-through removal tool, capable of batch application on a large number of images, of the order of hundred thousands, we used machine learning and robust statistical methods with four different methods, and applied them to two medieval manuscripts. The methods used are (i) non-local means (NLM); (ii) Gaussian mixture models (GMMs); (iii) biweight estimation; and (iv) Gaussian blur. The application of these methods to the two quoted manuscripts shows that these methods are, in general, quite effective in bleed-through removal, but the selection of the method has to be performed according to the characteristics of the manuscript, e.g., if there is no ink fading and the difference between bleed-through pixels and the foreground text is clear, we can use a stronger model without the risk of losing important information. Conversely, if the distinction between bleed-through and foreground pixels is less pronounced, it is better to use a weaker model to preserve useful details. Full article

Between the eighth and ninth centuries, the world entered a second period of strong winter monsoons, which precipitated a series of recurrent natural disasters, including reduced summer rainfall and prolonged droughts. The various types of droughts that occurred in southeastern China are documented in historical records, which also include the official-led ritual prayers to the local deities that were conducted during these challenging periods. As evidenced in these historical records, officials implemented a series of measures to provide solace to the populace, including the restoration of shrines and temples and the offering of sacrifices and prayers to the local deities, such as the Wutang God 吳塘神 and the Chutan God 儲潭神. These actions were intended to leverage the influence of the local deities to mobilise labour and financial resources for the implementation of public works, including the reclamation of barren land and the construction of dikes and ponds. These initiatives ultimately proved instrumental in enabling the populace to withstand the adverse effects of disasters. This approach represents a distinctive strategy for coping with drought in ancient China. It may provide insights into how governments and non-governmental organisations can utilise the influence of religious beliefs to unite people in addressing the climate crisis in the present era. Full article

A common cause of deterioration in historic manuscripts is ink transparency or bleeding from the opposite page. Philologists and paleographers can significantly benefit from minimizing these interferences when attempting to decipher the original text. Additionally, computer-aided text analysis can also gain from such text enhancement. In previous work, we proposed the use of neural networks (NNs) in combination with a data model that characterizes the damage when both sides of a page have been digitized. This approach offers the distinct advantage of allowing the creation of an artificial training set that teaches the NN to differentiate between clean and damaged pixels. We tested this concept using a shallow NN, which proved effective in categorizing texts with varying levels of deterioration. In this study, we adapt the NN design to tackling remaining classification uncertainties caused by areas of text overlap, inhomogeneity, and peaks of degradation. Specifically, we introduce a new output class for pixels within overlapping text areas and incorporate additional features related to the pixel context information to promote the same classification for pixels adjacent to each other. Our experiments demonstrate that these enhancements significantly improve the classification accuracy. This improvement is evident in the quality of both binarization, which aids in text analysis, and virtual restoration, aimed at recovering the manuscript’s original appearance. Tests conducted on a public dataset, using standard quality indices, reveal that the proposed method outperforms both our previous proposals and other notable methods found in the literature. Full article

The preservation of historical traditional architectural ensembles faces multifaceted challenges, and the need for facade renovation and updates has become increasingly prominent. In conventional architectural updating and renovation processes, assessing design schemes and the redesigning component are often time-consuming and labor-intensive. The knowledge-driven method utilizes a wide range of knowledge resources, such as historical documents, architectural drawings, and photographs, commonly used to guide and optimize the conservation, restoration, and management of architectural heritage. Recently, the emergence of artificial intelligence-generated content (AIGC) technologies has provided new solutions for creating architectural facades, introducing a new research paradigm to the renovation plans for historic districts with their variety of options and high efficiency. In this study, we propose a workflow combining Grasshopper with Stable Diffusion: starting with Grasshopper to generate concise line drawings, then using the ControlNet and low-rank adaptation (LoRA) models to produce images of traditional Minnan architectural facades, allowing designers to quickly preview and modify the facade designs during the renovation of traditional architectural clusters. Our research results demonstrate Stable Diffusion’s precise understanding and execution ability concerning architectural facade elements, capable of generating regional traditional architectural facades that meet architects’ requirements for style, size, and form based on existing images and prompt descriptions, revealing the immense potential for application in the renovation of traditional architectural groups and historic districts. It should be noted that the correlation between specific architectural images and proprietary term prompts still requires further addition due to the limitations of the database. Although the model generally performs well when trained on traditional Chinese ancient buildings, the accuracy and clarity of more complex decorative parts still need enhancement, necessitating further exploration of solutions for handling facade details in the future. Full article

The Tajos de Alhama de Granada, which since ancient times have inspired and surprised locals and strangers, especially foreign travelers, constituted a unique landscape, cultural and ethnological heritage of Spain, linked to water and its old flour mills. And, they are currently at serious risk of degradation. The aim of this research is to obtain a high-resolution 3D model capable of documenting this historical heritage environment with a high level of detail, using a methodology that includes small light weight LiDAR (Light Detection and Ranging) system for UAS (Unmanned Aircraft System). The model obtained should serve, on the one hand, as a valuable tool for knowledge and analysis of all the elements (river, lake, ditches, dams, mills, aqueducts, and paths) that made up this place, registered as a picturesque landscape for its extraordinary beauty and uniqueness, and on the other hand, as a basis for the development of rehabilitation and architectural restoration projects that would have to be undertaken to preserve this cultural and landscape legacy. Full article

Ancient grasslands are lost through transformation to agriculture, mining, and urban expansion. Land-use change leads to ecosystem degradation and a subsequent loss of biodiversity. Globally, degraded grasslands have become a priority for restoration efforts to recover lost ecosystem services. Although the ecological and social benefits of woody species and grasses are well documented, limited research has considered the use of forbs for restoration purposes despite their benefits (e.g., C sequestration and medicinal uses). The aim of this study was to determine if Crinum bulbispermum (Burm.f.) Milne-Redh. & Schweick., a medicinal geophyte, could form part of restoration initiatives to restore mine soils in grasslands of the South African Highveld. A pot experiment was conducted to assess the performance of C. bulbispermum in a random design, with three soil treatments varying in level of degradation and metal contamination. The plants were monitored for 12 months, and the morphological characters were measured monthly to assess performance and survival. Inductively coupled plasma mass spectrometry (ICP-MS) was used to determine the soil and plant tissue concentration of potentially toxic metals. The results indicated that mine tailings negatively affected the growth and development of C. bulbispermum. Although the survival rates indicated that it could survive on tailings, its below-par productivity indicated that the species is not ideal for restoration purposes unless the tailings are ameliorated with topsoil. Although there was root accumulation of metals (Co, Cd, Cu, Mo, and Zn), there was no translocation to the bulbs and leaves, which makes C. bulbispermum suitable for medicinal use even when grown on metal-enriched soil. This species may not be viable for phytoremediation but is a contender to be used in phytostabilization due to its ecological advantages and the fact that it does not accumulate or store metals. These findings underscore the importance of considering geophytes in grassland restoration strategies, expanding their ecological and societal benefits beyond conventional approaches. Full article

We present some results, obtained using a multi-scale approach, based on the employment of different and complementary techniques, i.e., Optical Microscopy (OM), Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDS), X-ray diffraction (XRD), Raman and µ-Raman spectroscopy, Fourier transform infrared (FT-IR) spectroscopy equipped with Attenuated Total Reflectance (ATR) analyses, Inductively Coupled Plasma–Mass Spectrometry (ICP-MS), and Thermal Ionization Mass Spectrometry (TIMS), of an integrated activity focused on the characterization of micro-fragments of original and previously restored paintings of the pictorial cycle at the San Panfilo Church in Tornimparte, sampled from specific areas of interest. The study was aimed, on one hand, at the identification of the overlapping restoration materials used during previous conservation interventions (documented and not), and, on the other hand, at understanding the degradation phenomena (current or previous) of the painted surfaces and the architectural structures. The study of stratigraphy allowed us to evaluate the number of layers and the materials (pigments, minerals, and varnishes) present in each layer. As the main result, the identification of blue, black, yellow, and red pigments (both ancient and modern) was achieved. In the case of blue pigments, original (azurite and lazurite) and retouching (Prussian blue and phthalo blue) materials were recognized, together with alteration products (malachite and atacamite). Traces of yellow ochre were found in the yellow areas, and carbon black in the blue and brown areas. In the latter, hematite and red ochre pigments were also recognized. The obtained results are crucial to support the methodological choices during the restoration intervention of the site, and help to ensure the compatibility principles of the materials on which a correct conservative approach is based. Full article

Open laboratories (OpenLabs) in Cultural Heritage institutions are an effective way to provide visibility into the behind-the-scenes processes and promote documentation data collected and produced by domain specialists. However, presenting these processes without proper explanation or communication with specialists may cause issues in terms of visitors’ understanding. To support OpenLabs and disseminate information, digital media and efficient data management can be utilized. The CAnTi (Conservation of Ancient Tiryns) project seeks to design and implement virtual and mixed reality applications that visualize conservation and restoration data, supporting OpenLab operations at the Acropolis of Ancient Tiryns. Semantic Web technologies will be used to model the digital content, facilitating organization and interoperability with external sources in the future. These applications will be part of the OpenLab activities on the site, enhancing visitors’ experiences and understanding of current and past conservation and restoration practices. Full article

Three-dimensional modeling and non-invasive diagnosis are fundamental prerequisites for planning reliable assessments of the seismic vulnerability, renovation and conservation of heritage buildings. In the case of multi-layered, huge and complex ancient constructions, various problems can be encountered in the early design phases of interventions, among which there is often a lack of an adequate building documentation. Such issues include drawings that are without a metric scale, not detailed, not updated or not reflecting the real situation. In addition, the fragility of these constructions requires an accurate census of every sign of deterioration in order to prepare an ad hoc intervention for the site. As an example, in this paper, the results of a survey regarding the Patriarchal Basilica of Santa Maria Assunta (Aquileia, Italy) are reported. The basilica has a rich history of about two thousand years. in which each era has marked the actual architectural layout with its own culture and art. The result is an intricate association of complementary and/or interdependent elements that make the building very complex. Given the need to obtain accurate documentation, a realistic representation and a simulation of the criticalities of the structure, which previously did not exist or were not sufficiently accurate, a multi-methodological and multi-scale diagnosis was performed. In detail, the ground-penetrating radar (GPR) technique was applied to verify the presence of structures still buried under some internal surfaces, and a topographic survey, terrestrial laser scanning (TLS), and structure for motion (SfM) aerial and terrestrial photogrammetry were integrated for the detailed survey of the entire internal and external macro-structure. The resulting outcome provided the comprehensive information needed for preparing projects for the preservation, management and restoration of the basilica and the buildings connected to it. Full article

The mosaic in the apse of the Church of S. Agnese fuori le mura in Rome represents one of the most important examples of the wall mosaics of the Roman Middle Ages. Although it is associated with Byzantine figurative culture, no scientific study has addressed this important piece of Italian art history. One factor that has probably limited and created difficulties for its analysis is the poor legibility of the original parts, which are compromised by heavy restorations affecting the gold background, the faces of the two male side figures, and the lower band of the mosaic. The present work describes how multispectral imaging provided significant guidance in the preliminary identification of possible original areas in this ancient wall mosaic. Through an interdisciplinary approach, the art historical background and historical graphic documentation of known restorations supported the use of multispectral imaging to recognize original parts. The initial results of the lab analyses (SEM-EDS and EMPA) of supposed original tesserae validated the hypothesis made a priori thanks to multispectral acquisition, opening up new application possibilities for use of this noninvasive technique in the preliminary in situ identification of original parts in restored glass wall mosaics. Full article

The Amur River Basin is located in China’s high-latitude and cold border areas. While inheriting the characteristics of Chinese traditional building, combined with its unique geographical and climatic environmental conditions, the local residential buildings have unique architectural features of cold climate adaptability. Outstanding insulation technology has become the main feature of the area, and has greatly affected the development of modern vernacular architecture. According to the archaeological reports and documents, this article selects ancient architectural sites from different historical periods as the research objects. Based on building restoration, AIRPAK software is used to simulate and analyze the indoor temperature of the building site, and to explore the effects of active heating measures, such as different forms of fire hypocaust system, and passive cold protection measures, such as different types of wall structures. According to archaeological information and simulation data, this paper summarizes the characteristics of the cold climate adaptability technology of ancient buildings in China’s cold border areas over different historical periods. Because of the relatively lagging development background of the Amur River Basin in modern times, the construction of its vernacular buildings continued to use the traditional low-tech insulation technology of ancient buildings to adapt to the cold environment. Therefore, attention and research on insulation technology of ancient buildings can provide a new perspective of architectural heritage protection in cold regions. Establishing a development model that combines archaeology and cultural heritage protection is an effective way to achieve the goals of architectural cultural heritage research and protection. Full article

In the presence of architecturally significant ruins, restoring and disseminating the idea of a testimony that has survived the destructive work of time is a cultural and social necessity that the use of advanced methods and tools allows to communicate in a timely and comprehensive manner. The integration of 3D surveying techniques and digital information production and management processes (graphic and alphanumeric, i.e., geometric information) makes it possible to put in place multifaceted and effective strategies. The article aims at describing the process of data acquisition (using applied photogrammetry) of the remains of a medieval cloister located on the outskirts of ancient Oppido Mamertina (RC, Italy). The use of the acquired point cloud, cleaned and optimised, made it possible to extract suitable orthophotos from which to derive the matrix profiles of the vaulted roof system. The information organisation of the model, which can be queried on time despite the generic level of detail, leads us to meditate on the change taking place in the field of documentation for urban environmental design and maintenance. Full article

(1) Background. The aim of this work is to combine non-invasive imaging with chemical characterization analyses to study original and restoration materials of a late 16th-century painting on a canvas representing the “Coronation of the Virgin with the Saints Ambrose and Jerome”, preserved in the Diocesan archive of Orte, a town in the district of Viterbo (Italy). The diagnostic campaign was addressed to support the restoration activities and the choice of the most suitable cleaning operations. (2) Methods. Both traditional analytical techniques and innovative multispectral imaging were applied to solve the diagnostic issues and best address the restoration of the painting. Specifically, hypercolorimetric multispectral imaging (HMI), X-ray fluorescence spectroscopy (XRF), Fourier transform infrared spectroscopy (FT-IR), optical microscopy, and gas chromatography coupled with mass spectrometry (GC-MS) were combined to obtain information on the general conservation state of the artwork and the characterization of pigments, organic binders, and superimposed materials, these last being particularly important to identify ancient and not-documented restoration intervention, enabling the correct choice of the most suitable and effective cleaning intervention. (3) Results. Multispectral data allowed us to differentiate and map original materials through infrared and ultraviolet false color images and spectral reflectance-based similarity maps, suggesting pigment attribution and focusing point analysis for characterization. This approach was particularly successful to identify and locate the presence of unaltered smalt blue in the first painting coat, which had been covered with other pigments, and to suggest the use of organic dye in mixtures with cinnabar and ochres. Spectroscopic and chromatographic techniques enabled us to identify the painting palette and confirm the use of oil-based binder for the pigments and characterize the altered top layers, made with a natural resin and an animal glue. (4) Conclusions. The characterization of the artwork’s materials was essential to select the most suitable methods and materials for the bio-cleaning, based on bacteria, experimented with during the restoration activities. Full article

As a result of human activity and environmental changes, several types of damages may occur to ancient mural paintings; indeed, lacunae, which refer to the area of paint layer loss, are the most prevalent kind. The presence of lacuna is an essential sign of the progress of mural painting deterioration. Most studies have focused on detecting and removing cracks from old paintings. However, lacuna extraction has not received the necessary consideration and is not well-explored. Furthermore, most recent studies have focused on using deep learning for mural protection and restoration, but deep learning requires a large amount of data and computational resources which is not always available in heritage institutions. In this paper, we present an efficient method to automatically extract lacunae and map deterioration from RGB images of ancient mural paintings of Bey’s Palace in Algeria. Firstly, a preprocessing was applied using Dark Channel Prior (DCP) to enhance the quality and improve visibility of the murals. Secondly, a determination of the training sample and pixel’s grouping was assigned to their closest sample based on Mahalanobis Distance (MD) by calculating both the mean and variance of the classes in three bands (R, G, and B), in addition to the covariance matrix of all the classes to achieve lacuna extraction of the murals. Finally, the accuracy of extraction was calculated. The experimental results showed that the proposed method can achieve a conspicuously high accuracy of 94.33% in extracting lacunae from ancient mural paintings, thus supporting the work of a specialist in heritage institutions in terms of the time- and cost-consuming documentation process. Full article