Few-Shot Domain Adaptation for Low Light RAW Image Enhancement

Enhancing practical low light raw images is a difficult task due to severe noise and color distortions from short exposure time and limited illumination. Despite the success of existing Convolutional Neural Network (CNN) based methods, their performance is not adaptable to different camera domains. In addition, such methods also require large datasets with short-exposure and corresponding long-exposure ground truth raw images for each camera domain, which is tedious to compile. To address this issue, we present a novel few-shot domain adaptation method to utilize the existing source camera labeled data with few labeled samples from the target camera to improve the target domain's enhancement quality in extreme low-light imaging. Our experiments show that only ten or fewer labeled samples from the target camera domain are sufficient to achieve similar or better enhancement performance than training a model with a large labeled target camera dataset. To support research in this direction, we also present a new low-light raw image dataset captured with a Nikon camera, comprising short-exposure and their corresponding long-exposure ground truth images.Comment: BMVC 2021 Best Student Paper Award (Runner-Up). Project Page: https://val.cds.iisc.ac.in/HDR/BMVC21/index.htm

Efficient and effective objective image quality assessment metrics

Acquisition, transmission, and storage of images and videos have been largely increased in recent years. At the same time, there has been an increasing demand for high quality images and videos to provide satisfactory quality-of-experience for viewers. In this respect, high dynamic range (HDR) imaging with higher than 8-bit depth has been an interesting approach in order to capture more realistic images and videos. Objective image and video quality assessment plays a significant role in monitoring and enhancing the image and video quality in several applications such as image acquisition, image compression, multimedia streaming, image restoration, image enhancement and displaying. The main contributions of this work are to propose efficient features and similarity maps that can be used to design perceptually consistent image quality assessment tools. In this thesis, perceptually consistent full-reference image quality assessment (FR-IQA) metrics are proposed to assess the quality of natural, synthetic, photo-retouched and tone-mapped images. In addition, efficient no-reference image quality metrics are proposed to assess JPEG compressed and contrast distorted images. Finally, we propose a perceptually consistent color to gray conversion method, perform a subjective rating and evaluate existing color to gray assessment metrics. Existing FR-IQA metrics may have the following limitations. First, their performance is not consistent for different distortions and datasets. Second, better performing metrics usually have high complexity. We propose in this thesis an efficient and reliable full-reference image quality evaluator based on new gradient and color similarities. We derive a general deviation pooling formulation and use it to compute a final quality score from the similarity maps. Extensive experimental results verify high accuracy and consistent performance of the proposed metric on natural, synthetic and photo retouched datasets as well as its low complexity. In order to visualize HDR images on standard low dynamic range (LDR) displays, tone-mapping operators are used in order to convert HDR into LDR. Given different depth bits of HDR and LDR, traditional FR-IQA metrics are not able to assess the quality of tone-mapped images. The existing full-reference metric for tone-mapped images called TMQI converts both HDR and LDR to an intermediate color space and measure their similarity in the spatial domain. We propose in this thesis a feature similarity full-reference metric in which local phase of HDR is compared with the local phase of LDR. Phase is an important information of images and previous studies have shown that human visual system responds strongly to points in an image where the phase information is ordered. Experimental results on two available datasets show the very promising performance of the proposed metric. No-reference image quality assessment (NR-IQA) metrics are of high interest because in the most present and emerging practical real-world applications, the reference signals are not available. In this thesis, we propose two perceptually consistent distortion-specific NR-IQA metrics for JPEG compressed and contrast distorted images. Based on edge statistics of JPEG compressed images, an efficient NR-IQA metric for blockiness artifact is proposed which is robust to block size and misalignment. Then, we consider the quality assessment of contrast distorted images which is a common distortion. Higher orders of Minkowski distance and power transformation are used to train a low complexity model that is able to assess contrast distortion with high accuracy. For the first time, the proposed model is used to classify the type of contrast distortions which is very useful additional information for image contrast enhancement. Unlike its traditional use in the assessment of distortions, objective IQA can be used in other applications. Examples are the quality assessment of image fusion, color to gray image conversion, inpainting, background subtraction, etc. In the last part of this thesis, a real-time and perceptually consistent color to gray image conversion methodology is proposed. The proposed correlation-based method and state-of-the-art methods are compared by subjective and objective evaluation. Then, a conclusion is made on the choice of the objective quality assessment metric for the color to gray image conversion. The conducted subjective ratings can be used in the development process of quality assessment metrics for the color to gray image conversion and to test their performance

Interaction on the Frontier of the 16\u3csup\u3eth\u3c/sup\u3e-17\u3csup\u3eth\u3c/sup\u3e Century World Economy: Late Fort Ancient Hide Production and Exchange at the Hardin Site, Greenup County, Kentucky

This study assesses the organization and intensity of hide processing from sequential occupations at the Late Fort Ancient (A.D. 1400-1680) Hardin Site located in the central Ohio Valley. Historical and archaeological sources were drawn on to develop expectations for production intensification: 1) an increase in production tool quantity, 2) an increase in production debris quantity, and 3) an increase in tool utilization intensity. Many Native groups situated on the periphery of early European colonies intensified hide production to meet demand generated by an emerging global trade in hides. As this economic activity intensified in the 16th and 17th centuries it incorporated and ever greater network of native communities. By documenting production intensification at the Hardin Site, this study evaluates the degree to which global markets incorporated regions beyond the colonial periphery before A.D. 1680. This study also examines the social dimensions of economic activity by asking who processed hides, who may have benefited from the products of this labor, and whether or not either of these were influenced by participation in the tumultuous interaction sphere of the eastern North American Contact Period

"The Neolithic Settlement of Aknashen (Ararat valley, Armenia)"

The Neolithic settlement of Aknashen (Ararat valley, Armenia): excavation seasons 2004-2015 is the first monograph devoted to the Neolithic period in Armenia. The research is based on an Armenian-French project, in which specialists from Canada, Romania, Germany and Greece also participated. The volume concerns the natural environment, material culture and subsistence economy of the populations of the first half of the 6th millennium BC, who established the first sedentary settlements in the alluvial plain of the Araxes river. The thickness of the cultural layer of Aknashen (almost 5m), the extent of the excavated areas and the multidisciplinary nature of the research, confer great importance upon this site for the study of the Neolithic, both in Armenia and in the South Caucasus as a whole. The publication examines the similarities and differences that exist between the sites established in the 6th millennium in the basins of the rivers Araxes (Armenia) and Kura (Georgia and Azerbaijan), as well as parallels with contemporary cultures in Southwest Asia. It also examines questions concerning the characterisation and periodisation of the Neolithic in the central part of the South Caucasus, the emergence of a production economy (pottery, animal husbandry, etc.) and the Neolithisation of this region

Multimedia Forensics

This book is open access. Media forensics has never been more relevant to societal life. Not only media content represents an ever-increasing share of the data traveling on the net and the preferred communications means for most users, it has also become integral part of most innovative applications in the digital information ecosystem that serves various sectors of society, from the entertainment, to journalism, to politics. Undoubtedly, the advances in deep learning and computational imaging contributed significantly to this outcome. The underlying technologies that drive this trend, however, also pose a profound challenge in establishing trust in what we see, hear, and read, and make media content the preferred target of malicious attacks. In this new threat landscape powered by innovative imaging technologies and sophisticated tools, based on autoencoders and generative adversarial networks, this book fills an important gap. It presents a comprehensive review of state-of-the-art forensics capabilities that relate to media attribution, integrity and authenticity verification, and counter forensics. Its content is developed to provide practitioners, researchers, photo and video enthusiasts, and students a holistic view of the field

Timeline design for visualising cultural heritage data

This thesis is concerned with the design of data visualisations of digitised museum, archive and library collections, in timelines. As cultural institutions digitise their collections—converting texts, objects, and artworks to electronic records—the volume of cultural data available grows. There is a growing perception, though, that we need to get more out of this data. Merely digitising does not automatically make collections accessible, discoverable and comprehensible, and standard interfaces do not necessarily support the types of interactions users wish to make. Data visualisations—this thesis focuses on interactive visual representations of data created with software—allow us to see an overview of, observe patterns in, and showcase the richness of, digitised collections. Visualisation can support analysis, exploration and presentation of collections for different audiences: research, collection administration, and the general public. The focus here is on visualising cultural data by time: a fundamental dimension for making sense of historical data, but also one with unique strangeness. Through cataloguing, cultural institutions define the meaning and value of items in their collections and the structure within which to make sense of them. By visualising threads in cataloguing data through time, can historical narratives be made visible? And is the data alone enough to tell the stories that people wish to tell? The intended audience for this research is cultural heritage institutions. This work sits at the crossroads between design, cultural heritage (particularly museology), and computing—drawing on the fields of digital humanities, information visualisation and human computer-interaction which also live in these overlapping spaces. This PhD adds clarity around the question of what cultural visualisation is (and can be) for, and highlights issues in the visualisation of qualitative or nominal data. The first chapter lays out the background, characterising cultural data and its visualisation. Chapter two walks through examples of existing cultural timeline visualisations, from the most handcrafted displays to automated approaches. At this point, the research agenda and methodology are set out. The next five chapters document a portfolio of visualisation projects, designing and building novel prototype timeline visualisations with data from the Wellcome Library and Victoria & Albert Museum, London, Cooper Hewitt Smithsonian Design Museum, New York City, and the Nordic Museum, Stockholm. In the process, a range of issues are identified for further discussion. The final chapters reflect on these projects, arguing that automated timeline visualisation can be a productive way to explore and present historical narratives in collection data, but a range of factors govern what is possible and useful. Trust in cultural data visualisation is also discussed. This research argues that visualising cultural data can add value to the data both for users and for data-holding institutions. However, that value is likely to be best achieved by customising a visualisation design to the dataset, audience and use case. Keywords: cultural heritage data; historical data; cultural analytics; cultural informatics; humanities visualisation; generous interfaces; digital humanities; design; information design; interface design; data visualisation; information visualisation; time; timeline; history; historiography; museums; museology; archives; chronographics

Long-term changes in the organization of lithic technology : a case study from the Imjin-Hantan River Area, Korea

This study is intended to furnish an explicability of hunter-gather's organizational model on the lithic technology. The fieldwork area is the Imjin-Hantan River Area (the IHRA) located at the midwestern part of the Korean Peninsula. The archaeological sites included in the fieldwork are Jangsanri (ca 0.2 Mya BP), Chongokni (ca 60 Kya BP), Juwolri, and Kawolri (younger than ca 50 Kya BP). In addition, a previously excavated Upper Palaeolithic assemblage of Janghungri (ca 23 Kya BP) is included in the quantitative analysis of lithic assemblages.For the background of the research area, chapter II is devoted to demonstrating the general environment of East Asia and current Quaternary research of Korea. Chapter III furnishes the basic knowledge on the geomorphological environment of the IHRA and the research history in this area for the last three decades was elaborated.Chapter IV is a description on the excavation fieldworks, introduction of the discovered lithic artifacts, and new age determination based on the K-Ar, IRSL, OSL, and AMS dating methods. Chapter V is the general characteristics on the IHRA lithic assemblage. Some descriptive details on the individual artifacts are presented and technological implications of lithic types are delineated. In addition, a general reduction sequence of the IHRA assemblage is proposed.Chapter VI is a quantitative analysis based on the exploratory data analysis (EDA); some geometric variables of artifacts were operationally defined for the purpose of acquiring more implicative analytical units. As a result of the analysis, it is revealed that the distinct interassemblage variability of raw material composition and of the morphological features of small tools and blanks constrained by differential reduction intensity can be explained in the context of the long-term-based strategic changes executed by the IHRA hominins.Chapter VII, based on the results from the fieldwork and lithic analysis, attempted to reconstruct the geological history of the IHRA in terms of hominid's land use patterns and relevant survival strategies. As a final remark, some unsolved issues were diagnosed and future research was expected for the continual research of the IHRA

"The Neolithic Settlement of Aknashen (Ararat valley, Armenia)"

The Neolithic settlement of Aknashen (Ararat valley, Armenia): excavation seasons 2004-2015 is the first monograph devoted to the Neolithic period in Armenia. The research is based on an Armenian-French project, in which specialists from Canada, Romania, Germany and Greece also participated. The volume concerns the natural environment, material culture and subsistence economy of the populations of the first half of the 6th millennium BC, who established the first sedentary settlements in the alluvial plain of the Araxes river. The thickness of the cultural layer of Aknashen (almost 5m), the extent of the excavated areas and the multidisciplinary nature of the research, confer great importance upon this site for the study of the Neolithic, both in Armenia and in the South Caucasus as a whole. The publication examines the similarities and differences that exist between the sites established in the 6th millennium in the basins of the rivers Araxes (Armenia) and Kura (Georgia and Azerbaijan), as well as parallels with contemporary cultures in Southwest Asia. It also examines questions concerning the characterisation and periodisation of the Neolithic in the central part of the South Caucasus, the emergence of a production economy (pottery, animal husbandry, etc.) and the Neolithisation of this region

Multimedia Forensics

This book is open access. Media forensics has never been more relevant to societal life. Not only media content represents an ever-increasing share of the data traveling on the net and the preferred communications means for most users, it has also become integral part of most innovative applications in the digital information ecosystem that serves various sectors of society, from the entertainment, to journalism, to politics. Undoubtedly, the advances in deep learning and computational imaging contributed significantly to this outcome. The underlying technologies that drive this trend, however, also pose a profound challenge in establishing trust in what we see, hear, and read, and make media content the preferred target of malicious attacks. In this new threat landscape powered by innovative imaging technologies and sophisticated tools, based on autoencoders and generative adversarial networks, this book fills an important gap. It presents a comprehensive review of state-of-the-art forensics capabilities that relate to media attribution, integrity and authenticity verification, and counter forensics. Its content is developed to provide practitioners, researchers, photo and video enthusiasts, and students a holistic view of the field

Image and Video Forensics

Nowadays, images and videos have become the main modalities of information being exchanged in everyday life, and their pervasiveness has led the image forensics community to question their reliability, integrity, confidentiality, and security. Multimedia contents are generated in many different ways through the use of consumer electronics and high-quality digital imaging devices, such as smartphones, digital cameras, tablets, and wearable and IoT devices. The ever-increasing convenience of image acquisition has facilitated instant distribution and sharing of digital images on digital social platforms, determining a great amount of exchange data. Moreover, the pervasiveness of powerful image editing tools has allowed the manipulation of digital images for malicious or criminal ends, up to the creation of synthesized images and videos with the use of deep learning techniques. In response to these threats, the multimedia forensics community has produced major research efforts regarding the identification of the source and the detection of manipulation. In all cases (e.g., forensic investigations, fake news debunking, information warfare, and cyberattacks) where images and videos serve as critical evidence, forensic technologies that help to determine the origin, authenticity, and integrity of multimedia content can become essential tools. This book aims to collect a diverse and complementary set of articles that demonstrate new developments and applications in image and video forensics to tackle new and serious challenges to ensure media authenticity