대량의 멀티미디어 파일을 위한 미디어 스캐닝 기법의 개선

학위논문 (석사)-- 서울대학교 대학원 : 전기·컴퓨터공학부, 2015. 2. 신현식.최근에 개발된 스마트 기기들은 저장 장치의 멀티미디어 파일을 활용하기 위해 메타 정보를 스캐닝하여 데이터베이스화한다. 한편 저장장치의 용량 증가로 대량의 멀티미디어 파일을 저장하는 것이 가능해져, 기존의 미디어 스캐닝 방법을 사용하면 과도한 스캐닝 시간이 소요된다. 특히 스마트 기기에 연결된 외부 저장장치에 대한 스캐닝은 대규모로 빈번하게 이루어 질 수 있기 때문에 더욱 문제가 되며 개선된 미디어 스캐닝의 방법이 필요하다. 본 논문의 목적은 대량의 멀티미디어 파일에 대한 스캐닝 과정을 개선하여 소요 시간을 단축하는 것이다. 이를 위해 미디어 스캐닝이 필요한 상황과 기존 미디어 스캐닝의 방법을 분석하여 중요 요소들을 선정하고 각 요소 별 비중을 측정하였다.그리고 선정된 요소들이 사용하는 시스템 콜을 분석하여 stat 함수와 readdir 함수의 문제점을 찾아내어 개선하였다. 실험 결과 기존 데이터베이스를 검증하는 스캐닝 과정에서 55~89%의 시간이 단축됨을 밝혔다. 또한 미디어 파일 안에 있는 메타 정보의 위치가 비교적 일정함을 이용하여 간단한 프리페칭을 구현하였고, 새로운 파일을 파싱하는 과정에서도 환경에 따라 5~33%의 시간이 단축됨을 밝혔다.요약 목차 그림 목차 표 목차 제 1 장 서론 1.1 연구동기 1.2 연구 내용 및 의의 1.3 논문의 구성 제 2 장 연구 배경 2.1 미디어 파일 스캐닝 2.1.1 미디어 파일 스캐너의 구조 2.1.2 New scan 시나리오와 Check scan 시나리오 2.2 미디어 파일 스캐닝의 요소 2.3 관련 연구 2.3.1 파일 입축력 속도의 개선 2.3.2 디렉터리 읽기 속도의 개선 2.3.3 데이터베이스 처리 속도의 개선 제 3 장 미디어 파일 스캐닝 분석 3.1 Light Media Scanner 3.1.1 동작 순서 3.1.2 미디어 스캐닝 소요 시간 분석 3.2 주요 시스템 콜 분석 3.2.1 시스템 콜들의 비중 3.2.2 stat의 문제점 3.2.3 readdir의 개선 방향 제 4 장 미디어 파일 스캐닝의 개선 4.1 readdir의 수정 4.2 Cached stat 4.3 프리페칭 제 5 장 성능 평가 5.1 실험 환경 5.2 성능 측정 및 분석 5.2.1 Check scan 시나리오 5.2.2 New scan 시나리오 제 6 장 결론 및 향후 연구 방향 참고 문헌 AbstractMaste

Progressive refinement of colormapped image.

Kwong Lap-ming.Thesis (M.Phil.)--Chinese University of Hong Kong, 2001.Includes bibliographical references (leaves 101-[104]).Abstracts in English and Chinese.Chapter 1 --- Introduction to Image Communication --- p.1Chapter 1.1 --- Existing Approach improving Image Communication --- p.8Chapter 1.1.1 --- Data Compression --- p.8Chapter 1.1.2 --- Progressive Image Transmission --- p.10Chapter 2 --- Review of Progressive Image Transmission Methods --- p.13Chapter 2.1 --- Pyramidal Image Coding --- p.14Chapter 2.1.1 --- Expansive Image Pyramid --- p.15Chapter 2.1.2 --- Non-Expansive Image Pyramid --- p.18Chapter 2.1.3 --- Pros and Cons of Pyramidal Data Structure --- p.19Chapter 2.2 --- Hierarchical Data Structure with Bit Plane Transmission --- p.20Chapter 2.2.1 --- Bitwise Condensed Quadtree method (BCQ)[6] --- p.21Chapter 2.2.2 --- Progressive Transmission of Full-Search VQ[7] --- p.25Chapter 2.2.3 --- Pros and Cons of Hierarchical Data Structure with Bit Plane Transmission --- p.26Chapter 2.3 --- Embedded Transform Coding --- p.27Chapter 2.3.1 --- SPIHT method [16] --- p.27Chapter 2.3.2 --- Embedded DCT Method [13] --- p.30Chapter 2.3.3 --- Pros and Cons of Embedded Transform Coding --- p.31Chapter 2.4 --- Summary --- p.32Chapter 3 --- Progressive Refinement of Colormapped Image --- p.34Chapter 3.1 --- Colormapped Image --- p.36Chapter 3.1.1 --- Pros and Cons of the Usage of Colormapped Image --- p.37Chapter 3.2 --- Progressive Refinement in both Spatial and Contrast Resolutions --- p.38Chapter 4 --- The Design of Progressive Refinement of Colormapped Image --- p.42Chapter 4.1 --- The Scalar Quantization in the YCrCb color space --- p.44Chapter 4.1.1 --- The Color Space for Color Quantization --- p.44Chapter 4.1.2 --- Color Quantization --- p.44Chapter 4.1.3 --- The Order of Quantization --- p.47Chapter 4.1.4 --- Pixel Mapping --- p.55Chapter 4.2 --- Reordering Pixels --- p.58Chapter 4.3 --- Transmission Sequence --- p.61Chapter 4.4 --- Changing the progression rate of the spatial and the contrast resolution --- p.62Chapter 4.5 --- Data Transmission --- p.69Chapter 4.6 --- Displaying the image --- p.70Chapter 5 --- Results Analysis & Performance Evaluation --- p.72Chapter 5.1 --- Traffic overhead --- p.72Chapter 5.2 --- Performance Evaluation --- p.73Chapter 5.2.1 --- Experiment --- p.73Chapter 5.2.2 --- Comparison with other Methods --- p.81Chapter 5.2.3 --- Image quality variation --- p.93Chapter 6 --- Discussion and Conclusion --- p.97Chapter 6.1 --- Discussion --- p.97Chapter 6.2 --- Conclusion --- p.99Bibliography --- p.10

The VPS ReplaySuite: development and evaluation of a novel, Internet based telepathology tool

The ReplaySuite is a web-based telepathology tool that replicates the doubleheaded microscope environment online, enabling a reviewing pathologist to ‘replay’ an archived virtual slide examination. Examination-tracking data obtained by the Virtual Pathology Slide (VPS) virtual slide viewer is exploited, allowing a remote pathologist to review an examination conducted at a different time and location. This removes temporal and spatial issues associated with double-headed microscopy. In order to conduct a preliminary evaluation of the technology, 9 pathologists used the ReplaySuite to review examination replays and diagnostic data from archived examinations of 10 needlecore breast biopsies. Diagnostically difficult cases were most frequently evaluated, either via diagnostic concordance graphs or examination replays, and all 3 participants who replayed more than 10 examinations stated the ReplaySuite to be of some or great benefit in pathology training and quality assurance. Of those who replayed an examination by another pathologist, 83% (5/6) agreed that replays provided an insight into the examining pathologists diagnosis, and 33% (2/6) reconsidered their own diagnosis for at least one case. Of those who reconsidered their original diagnosis, all reclassified either concordant with group consensus or original glass slide diagnosis. This study demonstrated that the ReplaySuite was of potential benefit in pathology education, however the technology required evaluation in a setting that would facilitate its impact on diagnostic performance. Accordingly, a redeveloped VPS and ReplaySuite were incorporated into the EQUALIS External Quality Assurance (EQA) study in chronic hepatitis staging and grading. During the study, 9 Swedish pathology departments examined and scored digital representations of liver needlecore biopsies during two sessions, with 10 cases per session and two digital slides per case. Between scoring sessions, participants were provided with access to two supplementary electronic resources: the ReplaySuite, and a library of pre-selected reference images. Comparison of concordance with gold standard (KVAST group) scoring before and after electronic resource use facilitated the elucidation of impact on diagnostic performance. Between scoring sessions, participant concordance with KVAST staging increased by 18% (49%-67%), while concordance with KVAST grading increased by 20% (34%-54%). Mean staging un-weighted kappa improved from 0.347 to 0.554 (+0.207), or from ‘fair’ to ‘moderate’ exact agreement with KVAST staging. Linear weighted staging kappa improved from 0.603 to 0.688 (+0.085), indicating close agreement in both sessions. Mean grading unweighted kappa increased from 0.132 to 0.412 (+0.280), or from a ‘poor’ to ‘moderate’ level o f exact agreement with KVAST, while linear weighted kappa improved from 0.328 to 0.624 (+0.295), or from ‘fair’ to ‘good’ level of approximate agreement with KVAST. Subsequent to the EQA scheme, an expert liver pathologist used the ReplaySuite to evaluate study examinations, assessing examination technique and identifying sources of error. Examinations scoring concordant with KVAST were observed to exhibit acceptable examination technique more frequently than discordantly scoring examinations. When grading, 28% (46% - 18%) more concordant than discordant examinations were considered to have viewed sufficient tissue, and at the appropriate magnification. A similar disparity of 24% (59% - 35%) was observed in staging, suggesting that examination technique was important both when determining the degree of necroinflammation within a biopsy, and when ascertaining the extent of fibrosis. In assessing sources of error, the expert pathologist identified a potential source in 50% of grading examinations, with misinterpretation of observed pathology cited in 19%, and missed pathology (oversight) cited in 31% of grading examinations. Of the 41% of staging examinations in which a source was identified, misinterpretation of observed pathology was cited in 20% of examinations, and missed pathology (oversight) in 21% of examinations. This study demonstrated that the use of supplementary electronic resources could result in improvements in diagnostic performance. It also illustrated the significant ‘add on’ value that could be provided by the ReplaySuite in EQA, by providing means to assess not only diagnostic concordance, but also diagnostic technique and identify sources of error. In order to assess Irish trainee pathologist’s perceptions of computer-assisted learning (CAL), a number of commercial systems were utilised to incorporate digital slides into a postgraduate seminar series, and provide subsequent access to seminar digital slides, diagnoses and expert annotations online. All surveyed trainees considered the use of digital slides and expert annotations of benefit in pathology training, and considered the potential implementation of expert examination replays, online self-assessment and the capability to search online for material by organ, diagnosis or pathological feature of benefit. The work described herein illustrates that both expert and trainee pathologists alike consider the use of supplementary electronic resources of benefit in pathology education, and demonstrates that their use can improve diagnostic performance. The ability to evaluate participation in EQA studies via the ReplaySuite provides significant additional value to education schemes, providing a depth of assessment not possible with conventional microscopy

Development and evaluation of the virtual pathology slide: a new tool for understanding inter-observer variability in diagnostic microscopy

The VPS (Virtual Pathology Slide) is a microscope emulator enabling the examination of pathology slides via the Internet or CD-Rom. A novel feature of the VPS is the ability to record the migratory traces (image viewed and magnification) of pathologists examinations on a remote relational database located in Dublin City University. In order to evaluate the VPS, Ten breast needle core biopsies were randomly selected and presented to 17 pathologists or trainee pathologists with at least 2 years experience in pathology practice. Participants were required to examine each case online and provide a diagnostic classification using online feedback forms, based on the Core Biopsy Reporting Guidelines for Non-operative Diagnostic Procedures and Reporting in Breast Cancer screening as used by the British National Co-ordinating Committee for Breast Screening Pathology. The recorded data permitted examination of interobserver variability and user satisfaction. The study demonstrated that Pathologists can make a correct diagnosis using the VPS. Consensus glass diagnosis agreed with consensus VPS diagnosis in 9 out of 10 cases. Consensus diagnosis for Slide 8 differed from glass slide diagnosis by one classification grade. Several Participants using the VPS achieved strong individual performance, with 10 of the 17 participants displaying “good” to “exce//e«i” (>0.6) agreement with VPS consensus, based on a weighted Kappa rating. Modification of diagnostic classification based on a review of text diagnosis resulted in VPS consensus diagnosis for Slide 8 concurring with glass slide diagnosis and demonstrated a lack o f familiarity and understanding amongst participants in the application of the applied diagnostic guidelines, particularly in the diagnosis of Intraductal Pappilloma. Modification of diagnostic classification based on text diagnosis increased average overall slide consensus from 66.5% to 69.4% but decreased individual Kappa performance by 0.76 to 0.72. Participants diagnostic performance was found to be unrelated to their confidence in making a diagnostic decision using the VPS. Perception of image quality was demonstrated to be clearly dependent on participants screen resolution and colour depth, but was shown not to influence diagnostic performance. Perception of download speed was found to be unrelated to individual diagnostic performance. However, it was demonstrated that there is an increase in the number of fields of view examined by participants as their perception of download speed improves. The number of fields of view examined per slide was found to be representative of the histological difficulty in interpreting a case. In general, as slide consensus decreases, the number of fields view examined for that slide increases. The number of fields of view examined at a particular magnification was found to be unique for each slide and dependent on the histological complexity of each slide. To elucidate reasons for diagnostic inconsistency, a software application called ‘Bitmapper’ was developed. This generates a graphical representation of a diagnostic trace using data stored on the VPS database. This takes the form of 128x128 pixel bitmap image, where each pixel is representative of an individual field of view on a VPS slide at the highest magnification available. The colour value of each pixel is determined by whether the field of view it represents has been viewed, and if so, at what magnification. This diagnostic trace was used to locate hotspot regions of potential diagnostic importance within a slide. For each of the slides a pathologist, specialist in breast disorders, examined images from these hotspots and successfully deduced a reason for diagnostic inconsistencies. This demonstrated that Bitmapper is an extremely useful tool for determining reasons for observer variation. The development of the VPS and ancillary software tools was successful in that pathologists were willing to use the system. Pathologists could make a correct diagnostic decision using the system. The degree of observer variation could be quantified and using Bitmapper, reasons for observer variation could be determined. This technology has applications in determining the cause of observer variability and will prove a useful tool in external quality assurance studies (EQA) in pathology

Modelo para digitalización de documentos, aplicado a una obra perteneciente a la colección libros antiguos y valiosos de la Biblioteca de Filosofía y Teología Mario Valenzuela. S.J.

Profesional en Ciencia de la Información - Bibliotecólogo (a)Pregrad

Digital Pathology: The Time Is Now to Bridge the Gap between Medicine and Technological Singularity

Digitalization of the imaging in radiology is a reality in several healthcare institutions worldwide. The challenges of filing, confidentiality, and manipulation have been brilliantly solved in radiology. However, digitalization of hematoxylin- and eosin-stained routine histological slides has shown slow movement. Although the application for external quality assurance is a reality for a pathologist with most of the continuing medical education programs utilizing virtual microscopy, the abandonment of traditional glass slides for routine diagnostics is far from the perspectives of many departments of laboratory medicine and pathology. Digital pathology images are captured as images by scanning and whole slide imaging/virtual microscopy can be obtained by microscopy (robotic) on an entire histological (microscopic) glass slide. Since 1986, services using telepathology for the transfer of images of anatomic pathology between detached locations have benefited countless patients globally, including the University of Alberta. The purpose of specialist recertification or re-validation for the Royal College of Pathologists of Canada belonging to the Royal College of Physicians and Surgeons of Canada and College of American Pathologists is a milestone in virtual reality. Challenges, such as high bandwidth requirement, electronic platforms, the stability of the operating systems, have been targeted and are improving enormously. The encryption of digital images may be a requirement for the accreditation of laboratory services—quantum computing results in quantum-mechanical phenomena, such as superposition and entanglement. Different from binary digital electronic computers based on transistors where data are encoded into binary digits (bits) with two different states (0 and 1), quantum computing uses quantum bits (qubits), which can be in superpositions of states. The use of quantum computing protocols on encrypted data is crucial for the permanent implementation of virtual pathology in hospitals and universities. Quantum computing may well represent the technological singularity to create new classifications and taxonomic rules in medicine

Cruiser and PhoTable: Exploring Tabletop User Interface Software for Digital Photograph Sharing and Story Capture

Digital photography has not only changed the nature of photography and the photographic process, but also the manner in which we share photographs and tell stories about them. Some traditional methods, such as the family photo album or passing around piles of recently developed snapshots, are lost to us without requiring the digital photos to be printed. The current, purely digital, methods of sharing do not provide the same experience as printed photographs, and they do not provide effective face-to-face social interaction around photographs, as experienced during storytelling. Research has found that people are often dissatisfied with sharing photographs in digital form. The recent emergence of the tabletop interface as a viable multi-user direct-touch interactive large horizontal display has provided the hardware that has the potential to improve our collocated activities such as digital photograph sharing. However, while some software to communicate with various tabletop hardware technologies exists, software aspects of tabletop user interfaces are still at an early stage and require careful consideration in order to provide an effective, multi-user immersive interface that arbitrates the social interaction between users, without the necessary computer-human interaction interfering with the social dialogue. This thesis presents PhoTable, a social interface allowing people to effectively share, and tell stories about, recently taken, unsorted digital photographs around an interactive tabletop. In addition, the computer-arbitrated digital interaction allows PhoTable to capture the stories told, and associate them as audio metadata to the appropriate photographs. By leveraging the tabletop interface and providing a highly usable and natural interaction we can enable users to become immersed in their social interaction, telling stories about their photographs, and allow the computer interaction to occur as a side-effect of the social interaction. Correlating the computer interaction with the corresponding audio allows PhoTable to annotate an automatically created digital photo album with audible stories, which may then be archived. These stories remain useful for future sharing -- both collocated sharing and remote (e.g. via the Internet) -- and also provide a personal memento both of the event depicted in the photograph (e.g. as a reminder) and of the enjoyable photo sharing experience at the tabletop. To provide the necessary software to realise an interface such as PhoTable, this thesis explored the development of Cruiser: an efficient, extensible and reusable software framework for developing tabletop applications. Cruiser contributes a set of programming libraries and the necessary application framework to facilitate the rapid and highly flexible development of new tabletop applications. It uses a plugin architecture that encourages code reuse, stability and easy experimentation, and leverages the dedicated computer graphics hardware and multi-core processors of modern consumer-level systems to provide a responsive and immersive interactive tabletop user interface that is agnostic to the tabletop hardware and operating platform, using efficient, native cross-platform code. Cruiser's flexibility has allowed a variety of novel interactive tabletop applications to be explored by other researchers using the framework, in addition to PhoTable. To evaluate Cruiser and PhoTable, this thesis follows recommended practices for systems evaluation. The design rationale is framed within the above scenario and vision which we explore further, and the resulting design is critically analysed based on user studies, heuristic evaluation and a reflection on how it evolved over time. The effectiveness of Cruiser was evaluated in terms of its ability to realise PhoTable, use of it by others to explore many new tabletop applications, and an analysis of performance and resource usage. Usability, learnability and effectiveness of PhoTable was assessed on three levels: careful usability evaluations of elements of the interface; informal observations of usability when Cruiser was available to the public in several exhibitions and demonstrations; and a final evaluation of PhoTable in use for storytelling, where this had the side effect of creating a digital photo album, consisting of the photographs users interacted with on the table and associated audio annotations which PhoTable automatically extracted from the interaction. We conclude that our approach to design has resulted in an effective framework for creating new tabletop interfaces. The parallel goal of exploring the potential for tabletop interaction as a new way to share digital photographs was realised in PhoTable. It is able to support the envisaged goal of an effective interface for telling stories about one's photos. As a serendipitous side-effect, PhoTable was effective in the automatic capture of the stories about individual photographs for future reminiscence and sharing. This work provides foundations for future work in creating new ways to interact at a tabletop and to the ways to capture personal stories around digital photographs for sharing and long-term preservation

Cruiser and PhoTable: Exploring Tabletop User Interface Software for Digital Photograph Sharing and Story Capture

Digital photography has not only changed the nature of photography and the photographic process, but also the manner in which we share photographs and tell stories about them. Some traditional methods, such as the family photo album or passing around piles of recently developed snapshots, are lost to us without requiring the digital photos to be printed. The current, purely digital, methods of sharing do not provide the same experience as printed photographs, and they do not provide effective face-to-face social interaction around photographs, as experienced during storytelling. Research has found that people are often dissatisfied with sharing photographs in digital form. The recent emergence of the tabletop interface as a viable multi-user direct-touch interactive large horizontal display has provided the hardware that has the potential to improve our collocated activities such as digital photograph sharing. However, while some software to communicate with various tabletop hardware technologies exists, software aspects of tabletop user interfaces are still at an early stage and require careful consideration in order to provide an effective, multi-user immersive interface that arbitrates the social interaction between users, without the necessary computer-human interaction interfering with the social dialogue. This thesis presents PhoTable, a social interface allowing people to effectively share, and tell stories about, recently taken, unsorted digital photographs around an interactive tabletop. In addition, the computer-arbitrated digital interaction allows PhoTable to capture the stories told, and associate them as audio metadata to the appropriate photographs. By leveraging the tabletop interface and providing a highly usable and natural interaction we can enable users to become immersed in their social interaction, telling stories about their photographs, and allow the computer interaction to occur as a side-effect of the social interaction. Correlating the computer interaction with the corresponding audio allows PhoTable to annotate an automatically created digital photo album with audible stories, which may then be archived. These stories remain useful for future sharing -- both collocated sharing and remote (e.g. via the Internet) -- and also provide a personal memento both of the event depicted in the photograph (e.g. as a reminder) and of the enjoyable photo sharing experience at the tabletop. To provide the necessary software to realise an interface such as PhoTable, this thesis explored the development of Cruiser: an efficient, extensible and reusable software framework for developing tabletop applications. Cruiser contributes a set of programming libraries and the necessary application framework to facilitate the rapid and highly flexible development of new tabletop applications. It uses a plugin architecture that encourages code reuse, stability and easy experimentation, and leverages the dedicated computer graphics hardware and multi-core processors of modern consumer-level systems to provide a responsive and immersive interactive tabletop user interface that is agnostic to the tabletop hardware and operating platform, using efficient, native cross-platform code. Cruiser's flexibility has allowed a variety of novel interactive tabletop applications to be explored by other researchers using the framework, in addition to PhoTable. To evaluate Cruiser and PhoTable, this thesis follows recommended practices for systems evaluation. The design rationale is framed within the above scenario and vision which we explore further, and the resulting design is critically analysed based on user studies, heuristic evaluation and a reflection on how it evolved over time. The effectiveness of Cruiser was evaluated in terms of its ability to realise PhoTable, use of it by others to explore many new tabletop applications, and an analysis of performance and resource usage. Usability, learnability and effectiveness of PhoTable was assessed on three levels: careful usability evaluations of elements of the interface; informal observations of usability when Cruiser was available to the public in several exhibitions and demonstrations; and a final evaluation of PhoTable in use for storytelling, where this had the side effect of creating a digital photo album, consisting of the photographs users interacted with on the table and associated audio annotations which PhoTable automatically extracted from the interaction. We conclude that our approach to design has resulted in an effective framework for creating new tabletop interfaces. The parallel goal of exploring the potential for tabletop interaction as a new way to share digital photographs was realised in PhoTable. It is able to support the envisaged goal of an effective interface for telling stories about one's photos. As a serendipitous side-effect, PhoTable was effective in the automatic capture of the stories about individual photographs for future reminiscence and sharing. This work provides foundations for future work in creating new ways to interact at a tabletop and to the ways to capture personal stories around digital photographs for sharing and long-term preservation

Top 10 technology opportunities : tips and tools

https://egrove.olemiss.edu/aicpa_guides/1610/thumbnail.jp

Digitalización de imágenes aplicada a la conservación y difusión de fotografía patrimonial: la experiencia de la Fototeca Andina, Centro Bartolomé de Las Casas (CBC), Cusco

Busca identificar los factores que se deben tener en cuenta a la hora de desarrollar un proyecto de digitalización de colecciones fotográficas. Para ello se eligió trabajar con las colecciones de la Fototeca Andina del Centro Bartolomé de Las Casas del Cusco que representan un conjunto voluminoso de imágenes diversas y de mucho valor, únicas en el Perú. Los archivos no sólo ilustran un panorama completo de la sociedad andina peruana entre 1890 y 1970, de importancia considerable para investigadores tanto de las humanidades y las artes, sino también reflejan una amplia gama de ejemplos de técnicas fotográficas por lo que se constituye en un registro tangible del desarrollo de la fotografía en el Perú; que merece conservarse y difundirse ampliamente.Trabajo de suficiencia profesiona