{ "types" : { "Bookmark" : { "pluralLabel" : "Bookmarks" }, "Publication" : { "pluralLabel" : "Publications" }, "GoldStandardPublication" : { "pluralLabel" : "GoldStandardPublications" }, "GoldStandardBookmark" : { "pluralLabel" : "GoldStandardBookmarks" }, "Tag" : { "pluralLabel" : "Tags" }, "User" : { "pluralLabel" : "Users" }, "Group" : { "pluralLabel" : "Groups" }, "Sphere" : { "pluralLabel" : "Spheres" } }, "properties" : { "count" : { "valueType" : "number" }, "date" : { "valueType" : "date" }, "changeDate" : { "valueType" : "date" }, "url" : { "valueType" : "url" }, "id" : { "valueType" : "url" }, "tags" : { "valueType" : "item" }, "user" : { "valueType" : "item" } }, "items" : [ { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2933e2b9635994f5e5d8129992c775012/jmueller", "tags" : [ "behaviour","compression","concrete","concrete,","failure","graded","lightweight","materials,","normal","sobek","test,","weight" ], "intraHash" : "933e2b9635994f5e5d8129992c775012", "interHash" : "d5b022689f5bd4641998f6d029a26d4a", "label" : "Energy absorption in functionally graded concrete under compression", "user" : "jmueller", "description" : "", "date" : "2023-11-27 15:10:57", "changeDate" : "2023-11-27 15:10:57", "count" : 1, "pub-type": "article", "journal": "Bulletin of the Polytechnic Institute of Jassy / Constructions, Architecture Section", "year": "2018", "url": "", "author": [ "Traian-Nicu Toader","Walter Haase","Werner Sobek" ], "authors": [ {"first" : "Traian-Nicu", "last" : "Toader"}, {"first" : "Walter", "last" : "Haase"}, {"first" : "Werner", "last" : "Sobek"} ], "volume": "64=68","number": "4","pages": "9--24","abstract": "Functionally graded concrete building components exhibit a density variation of the inner structure in accordance to the stresses that occur locally under load. Such building components are meant to have similar load bearing capacity, lower mass and higher performances for energy dissipation compared to those made of homogeneous distributed normal weight concrete. For the specimen preparation of graded concrete samples two production methods were used: casting and dry spraying. The purpose is to understand the relation between the alternation of concrete layers with various densities and the amount of energy absorbed. To evaluate the energy absorption capacity, cubes of equal mass but with different gradation layouts have been tested against uniaxial compression forces. Results show that the compressive strength and the amount of energy absorbed for the tested functionally graded concrete cubes is influenced by the layout design as well as by the production technique.", "bibtexKey": "toader_energy_2018" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/20e9dbe076502380e2b8e70a80da95818/inspo5", "tags" : [ "Age-dependent","Axial","Inspo","Microstructural","Morphometry","Oryctolagus","Semi-confined","Siebert","Soleus","characteristics","compression","cuniculus","muscle","properties","tests","tissue" ], "intraHash" : "0e9dbe076502380e2b8e70a80da95818", "interHash" : "6afbb85807dbc73f3599b68ac7ec0018", "label" : "Age-dependent mechanical and microstructural properties of the rabbit soleus muscle", "user" : "inspo5", "description" : "", "date" : "2022-07-19 11:10:29", "changeDate" : "2022-07-19 09:10:56", "count" : 1, "pub-type": "article", "journal": "Acta Biomaterialia","publisher":"Elsevier BV", "year": "2021", "url": "https://doi.org/10.1016%2Fj.actbio.2021.07.066", "author": [ "Kay Leichsenring","Asha Viswanathan","Steven Kutschke","Markus Siebert, TobiasBöl" ], "authors": [ {"first" : "Kay", "last" : "Leichsenring"}, {"first" : "Asha", "last" : "Viswanathan"}, {"first" : "Steven", "last" : "Kutschke"}, {"first" : "Markus", "last" : "Siebert, TobiasBöl"} ], "editor": [ "Tobias Siebert" ], "editors": [ {"first" : "Tobias", "last" : "Siebert"} ], "volume": "134","pages": "453--465","abstract": "During growth there are serious changes in the skeletal muscles to compensate for the changed requirements in terms of body weight and size. In this study, the age-dependent (between 21 and 100 days) mechanical and microstructural properties of rabbit soleus muscle tissue were investigated. For this purpose, morphological properties (animal mass, soleus muscle mass, tibial length) were measured at 5 different times during aging. On the other hand, fibre orientation-dependent axial and semi-confined compression experiments were realised. In addition, the essential components (muscle fibres, extracellular matrix, remaining components), dominating the microstructure of muscle tissue, were analysed. While the mechanical results show hardly any age-dependent differences, the morphological and microstructural results show clear age-dependent differences. All morphological parameters increase significantly (animal mass by 839.2%, muscle mass 1050.6%, tibial length 233.6%). In contrast, microstructural parameters change differently. The percentage of fibres (divided into slow-twitch (ST) and fast-twitch (FT) fibres) increases significantly (137.6%), while the proportions of the extracellular matrix and the remaining components (48.2% and 46.1%) decrease. At the same time, the cross-sectional area of the fibres increases significantly (697.9%). The totality of this age-dependent information provides a deeper understanding of age-related changes in muscle structure and function and may contribute to successful development and validation of growth models in the future.\n\nStatement of significance\nThis article reports the first comprehensive data set on age-dependent morphological (animal mass, soleus muscle mass, tibial length), mechanical (axial and semi-confined compression), and microstructural (muscle fibres, extracellular matrix, remaining components) properties of the rabbit soleus muscle. On the one hand, the results of this study contribute to the understanding of muscle mechanics and thus to understanding of load transfer mechanisms inside the muscle tissue during growth. On the other hand, these results are relevant to the fields of constitutive formulation of age-dependent muscle tissue.", "doi" : "10.1016/j.actbio.2021.07.066", "bibtexKey": "Leichsenring_2021" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/29d530f5c074dc9af0e1c475c6ea3ca48/inspo5", "tags" : [ "architecture","compression","contraction","dynamics","load","muscle","sonography","transverse","ultrasound" ], "intraHash" : "9d530f5c074dc9af0e1c475c6ea3ca48", "interHash" : "7bc93b91d4afa86288032a24d5ee4708", "label" : "The Effect of Multidirectional Loading on Contractions of the M. Medial Gastrocnemius", "user" : "inspo5", "description" : "", "date" : "2022-07-19 11:10:29", "changeDate" : "2022-07-19 09:10:56", "count" : 2, "pub-type": "article", "journal": "Frontiers in Physiology","publisher":"Frontiers Media SA", "year": "2021", "url": "https://doi.org/10.3389%2Ffphys.2020.601799", "author": [ "David S. Ryan","Norman Stutzig","Andreas Helmer","Tobias Siebert","James M. Wakeling" ], "authors": [ {"first" : "David S.", "last" : "Ryan"}, {"first" : "Norman", "last" : "Stutzig"}, {"first" : "Andreas", "last" : "Helmer"}, {"first" : "Tobias", "last" : "Siebert"}, {"first" : "James M.", "last" : "Wakeling"} ], "editor": [ "Tobias Siebert" ], "editors": [ {"first" : "Tobias", "last" : "Siebert"} ], "volume": "11", "doi" : "10.3389/fphys.2020.601799", "bibtexKey": "Ryan_2021" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2f111b48ee538c0a6f154e3c7705500a9/petraheim", "tags" : [ "2015","adaptic","baharlou","behavioural","composite","compression","design","dörstelmann","fabrication","fiber","framework","itke","knippers","koslowski","menges","pneumatic","prado","robotic","schieber","shell","vasey" ], "intraHash" : "f111b48ee538c0a6f154e3c7705500a9", "interHash" : "6781df1d9f3eaac3c0febf40aaad0835", "label" : "Behavioural Design and Adaptic Robotic Fabrication of Fiber Composite Compresion Shell with Pneumatic Formwork", "user" : "petraheim", "description" : "", "date" : "2020-05-19 14:24:15", "changeDate" : "2020-06-02 10:08:04", "count" : 1, "pub-type": "inproceedings", "booktitle": "Acadia 2015","address":"Cincinnati, Ohio, US", "year": "2015", "url": "", "author": [ "Lauren Vasey","E. Baharlou","Moritz Dörstelmann","Valentin Koslowski","Marshall Prado","Gundula Schieber","Achim Menges","Jan Knippers" ], "authors": [ {"first" : "Lauren", "last" : "Vasey"}, {"first" : "E.", "last" : "Baharlou"}, {"first" : "Moritz", "last" : "Dörstelmann"}, {"first" : "Valentin", "last" : "Koslowski"}, {"first" : "Marshall", "last" : "Prado"}, {"first" : "Gundula", "last" : "Schieber"}, {"first" : "Achim", "last" : "Menges"}, {"first" : "Jan", "last" : "Knippers"} ], "pages": "297 \u2013 309", "language" : "eng", "bibtexKey": "vasey2015behavioural" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2f3150076036f1c8aed879c8549405c7b/annettegugel", "tags" : [ "Clustering","Compression","Computationsend:unibiblio","Data","Fast","Flow","Meter","Power","Smart" ], "intraHash" : "f3150076036f1c8aed879c8549405c7b", "interHash" : "3268ed35ada183abacb542d5e70381b6", "label" : "Clustering of smart meter data for data compression and fast power flow computation", "user" : "annettegugel", "description" : "", "date" : "2020-04-20 14:24:31", "changeDate" : "2020-04-20 12:24:31", "count" : 2, "pub-type": "conference", "booktitle": "CIRED 2015, 23rd International Conference and Exhibition on Electricity Distribution, Lyon, Frankreich, June 15-18, 2015", "year": "2015", "url": "", "author": [ "Christoph Kattmann","Krzysztof Rudion","Stefan Tenbohlen" ], "authors": [ {"first" : "Christoph", "last" : "Kattmann"}, {"first" : "Krzysztof", "last" : "Rudion"}, {"first" : "Stefan", "last" : "Tenbohlen"} ], "eventtitle" : "CIRED 2015, 23rd International Conference and Exhibition on Electricity Distribution", "venue" : "Lyon, Frankreich", "language" : "eng", "eventdate" : "2015-06-15/2015-06-18", "bibtexKey": "kattmann2015clustering" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/24f72afb1cd7cba51df36966cd34bb6c6/ifsw", "tags" : [ "myown","gratings","from:tomdietrich","pulse","poster","compression" ], "intraHash" : "4f72afb1cd7cba51df36966cd34bb6c6", "interHash" : "2fd94058e44fbb762417bb6026fb1e16", "label" : "Large-area pulse compression gratings with high efficiency and high damage threshold", "user" : "ifsw", "description" : "", "date" : "2019-04-18 13:44:24", "changeDate" : "2019-04-18 11:44:24", "count" : 4, "pub-type": "misc", "booktitle": "EOS Topical meeting on Diffractive Optics", "year": "2017", "url": "", "author": [ "T. Dietrich","L. Müller","M. Rumpel","M. Möller","L. Gallais","C. Hönninger","M. Delaigue","M. Abdou Ahmed","T. Graf" ], "authors": [ {"first" : "T.", "last" : "Dietrich"}, {"first" : "L.", "last" : "Müller"}, {"first" : "M.", "last" : "Rumpel"}, {"first" : "M.", "last" : "Möller"}, {"first" : "L.", "last" : "Gallais"}, {"first" : "C.", "last" : "Hönninger"}, {"first" : "M.", "last" : "Delaigue"}, {"first" : "M.", "last" : "Abdou Ahmed"}, {"first" : "T.", "last" : "Graf"} ], "bibtexKey": "dietrich2017" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/24f72afb1cd7cba51df36966cd34bb6c6/tomdietrich", "tags" : [ "compression","gratings","myown","poster","pulse" ], "intraHash" : "4f72afb1cd7cba51df36966cd34bb6c6", "interHash" : "2fd94058e44fbb762417bb6026fb1e16", "label" : "Large-area pulse compression gratings with high efficiency and high damage threshold", "user" : "tomdietrich", "description" : "", "date" : "2018-03-29 18:54:28", "changeDate" : "2019-04-18 11:44:24", "count" : 4, "pub-type": "misc", "booktitle": "EOS Topical meeting on Diffractive Optics", "year": "2017", "url": "", "author": [ "T. Dietrich","L. Müller","M. Rumpel","M. Möller","L. Gallais","C. Hönninger","M. Delaigue","M. Abdou Ahmed","T. Graf" ], "authors": [ {"first" : "T.", "last" : "Dietrich"}, {"first" : "L.", "last" : "Müller"}, {"first" : "M.", "last" : "Rumpel"}, {"first" : "M.", "last" : "Möller"}, {"first" : "L.", "last" : "Gallais"}, {"first" : "C.", "last" : "Hönninger"}, {"first" : "M.", "last" : "Delaigue"}, {"first" : "M.", "last" : "Abdou Ahmed"}, {"first" : "T.", "last" : "Graf"} ], "bibtexKey": "dietrich2017" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2195ba5890dad28c886958f3f90d1b2a1/ifsw", "tags" : [ "compression","from:tomdietrich","gratings","myown","poster","pulse" ], "intraHash" : "195ba5890dad28c886958f3f90d1b2a1", "interHash" : "2fd94058e44fbb762417bb6026fb1e16", "label" : "Large-area pulse compression gratings with high efficiency and high damage threshold", "user" : "ifsw", "description" : "", "date" : "2018-03-29 18:54:28", "changeDate" : "2018-04-20 09:31:09", "count" : 4, "pub-type": "inproceedings", "booktitle": "EOS Topical meeting on Diffractive Optics", "year": "2017", "url": "", "author": [ "T. Dietrich","L. Müller","M. Rumpel","M. Möller","L. Gallais","C. Hönninger","M. Delaigue","M. Abdou Ahmed","T. Graf" ], "authors": [ {"first" : "T.", "last" : "Dietrich"}, {"first" : "L.", "last" : "Müller"}, {"first" : "M.", "last" : "Rumpel"}, {"first" : "M.", "last" : "Möller"}, {"first" : "L.", "last" : "Gallais"}, {"first" : "C.", "last" : "Hönninger"}, {"first" : "M.", "last" : "Delaigue"}, {"first" : "M.", "last" : "Abdou Ahmed"}, {"first" : "T.", "last" : "Graf"} ], "bibtexKey": "dietrich2017" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/24ad0d7a01b29554c1add6721d17c4c9f/hermann", "tags" : [ "(CLT);","(Fagus","(Picea","Beech","Bending","Compression","Finite","Rolling","Shear","Spruce","abies);","analogy","analysis;","element","gamma-Method;","method}","modulus;","shear","strength;","sylvatica);","test;","timber","wood","{Cross-laminated" ], "intraHash" : "4ad0d7a01b29554c1add6721d17c4c9f", "interHash" : "201f166932d880d63991d3876b9f56c0", "label" : "Hybrid cross-laminated timber plates with beech wood cross-layers", "user" : "hermann", "description" : "", "date" : "2017-05-18 11:32:12", "changeDate" : "2017-05-18 09:32:12", "count" : 2, "pub-type": "article", "journal": "CONSTRUCTION AND BUILDING MATERIALS","publisher":"ELSEVIER SCI LTD","address":"THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLAND", "year": "{2016}", "url": "", "author": [ "Simon Aicher","Maren Hirsch","Zachary Christian" ], "authors": [ {"first" : "Simon", "last" : "Aicher"}, {"first" : "Maren", "last" : "Hirsch"}, {"first" : "Zachary", "last" : "Christian"} ], "volume": "124","pages": "1007-1018","abstract": "A hybrid, three-layered, softwood-hardwood cross-laminated timber\n build-up with outer layers of European spruce (Picea abies) and a center\n cross-layer of European beech (Fagus sylvatica) has been investigated\n with regard to out-of-plane bending. The determination of the rolling\n shear properties of the beech cross-layer performed by different test\n and measurement methods comprising bending and compression shear tests\n was of primary interest. The shear capacity of the composite is\n significantly influenced by the spruce longitudinal shear strength at\n the beech-spruce interface. The characteristic values of rolling shear\n modulus and strength of the beech cross-layer from the bending tests\n were G(r), mean = 350 N/mm(2) and f(v,r,05) = 2.6 N/mm(2), respectively.\n Direct strain gauge measurements and compression shear tests resulted in\n 10-20\\% higher values. The high rolling shear properties render the\n shear lag implications of the softwood CLTs to a negligible quantity.\n The hybrid build-up can be designed as a rigid composite with small\n error versus a more exact analysis. The novel investigations reveal the\n great potential of mixed softwood-hardwood CLT build-ups for structural\n elements in the building sector, (C) 2016 Elsevier Ltd. All rights\n reserved.", "author-email" : "simon.aicher@mpa.uni-stuttgart.de", "issn" : "0950-0618", "keywords-plus" : "ROLLING SHEAR MODULUS; STRENGTH", "funding-acknowledgement" : "FNR, Fachagentur Nachwachsende Rohstoffe e.V. [22004014]; German\n Association of glulam manufacturers; company Eugen Decker Holzindustrie\n KG, Morbach, Germany", "research-areas" : "Construction & Building Technology; Engineering; Materials Science", "eissn" : "1879-0526", "number-of-cited-references" : "27", "affiliation" : "Aicher, S (Reprint Author), Univ Stuttgart, Mat Testing Inst MPA, Timber Construct, Pfaffenwaldring 4b, D-70569 Stuttgart, Germany.\n Aicher, Simon; Hirsch, Maren; Christian, Zachary, Univ Stuttgart, Mat Testing Inst MPA, Timber Construct, Pfaffenwaldring 4b, D-70569 Stuttgart, Germany.", "web-of-science-categories" : "Construction & Building Technology; Engineering, Civil; Materials\n Science, Multidisciplinary", "language" : "English", "funding-text" : "The work was financially supported by FNR, Fachagentur Nachwachsende\n Rohstoffe e.V., contract 22004014 within the ERA-WoodWisdom project\n ``European hardwoods for the building sector (EU Hardwoods)''. Further\n the financial and technical support by German Association of glulam\n manufacturers and the company Eugen Decker Holzindustrie KG, Morbach,\n Germany, is gratefully acknowledged.", "times-cited" : "1", "doi" : "10.1016/j.conbuildmat.2016.08.051", "bibtexKey": "ISI:000385319300100" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/295f9be406dc0c4cd546d093452dce436/thomasrichter", "tags" : [ "compression","image","myown" ], "intraHash" : "95f9be406dc0c4cd546d093452dce436", "interHash" : "401eaf16bd5a94f95373346a35ac6188", "label" : "Towards high-speed, low-complexity image coding: Variants and modification of JPEG 2000", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:41:13", "count" : 3, "pub-type": "inproceedings", "booktitle": "Applications of Digital Image Processing XXXV","publisher":"SPIE", "year": "2012", "url": "http://spie.org/Publications/Proceedings/Paper/10.1117/12.928173", "author": [ "Thomas Richter","Sven Simon" ], "authors": [ {"first" : "Thomas", "last" : "Richter"}, {"first" : "Sven", "last" : "Simon"} ], "editor": [ "Andrew G. Tescher" ], "editors": [ {"first" : "Andrew G.", "last" : "Tescher"} ], "volume": "8499","pages": "10","abstract": "Recently, the JPEG committee discussed the introduction of an \"ultrafast\" mode for JPEG 2000 encoding. This considered extension of the JPEG 2000 framework replaces the EBCOT coding by a combined Human- Runlength code, and adds an optional additional prediction step after quantization. While the resulting codec is not compatible with existing JPEG 2000, it still allows lossless transcoding from JPEG 2000 and back, and performance measurements show that it offers nearly the quality of JPEG 2000 and similar quality than JPEG XR at a much lower complexity comparable to the complexity of the IJG JPEG software. This work introduces the extension, and compares its performance with other JPEG standards and other extensions of JPEG 2000 currently under standardization.", "isbn" : "9780819492166", "doi" : "10.1117/12.928173", "bibtexKey": "richter2012towards" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2ec37260016b88bb9bbdb240dc718f710/thomasrichter", "tags" : [ "compression","image","jpeg2000","myown" ], "intraHash" : "ec37260016b88bb9bbdb240dc718f710", "interHash" : "6c17f6fd2d1971ae64bfcbdbf7519e0b", "label" : "On the JPEG 2000 Ultrafast Mode", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:40:02", "count" : 4, "pub-type": "inproceedings", "booktitle": "2012 IEEE International Conference on Image Processing ICIP 2012","publisher":"IEEE","address":"Lake Buena Vista, Florida, USA", "year": "2012", "url": "http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6467406", "author": [ "Thomas Richter","Sven Simon" ], "authors": [ {"first" : "Thomas", "last" : "Richter"}, {"first" : "Sven", "last" : "Simon"} ], "pages": "2501 - 2504","abstract": "Recently, the JPEG committee discussed the introduction of an ``ultrafast'' mode for JPEG 2000 encoding. This considered extension of the JPEG 2000 framework replaces the EBCOT coding by a combined Huffman-Runlength code, and adds an optional additional prediction step after quantization. While the resulting codec is not compatible with existing JPEG 2000, it still allows lossless transcoding from JPEG 2000 and back, and performance measurements show that it offers nearly the quality of JPEG 2000 and similar quality than JPEG XR at a much lower complexity comparable to the complexity of the IJG JPEG software. This work introduces the extension, and compares its performance with other JPEG standards and other extensions of JPEG 2000 currently under standardization.", "isbn" : "978-1-4673-2534-9", "doi" : "10.1109/ICIP.2012.6467406", "bibtexKey": "richter2012ultrafast" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2acc65a5b5aac63106242ee120d222865/thomasrichter", "tags" : [ "compression","image","learning","myown" ], "intraHash" : "acc65a5b5aac63106242ee120d222865", "interHash" : "dc5a74ed2ce76aef126b480c7c3277b1", "label" : "An Integrated Course on Wavelet-Based Image Compression - Learning Abstract Information Theory on Visual Data", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:39:55", "count" : 2, "pub-type": "inproceedings", "booktitle": "CISSE 2007", "year": "2007", "url": "", "author": [ "Sven Grottke","Sabina Jeschke","Thomas Richter" ], "authors": [ {"first" : "Sven", "last" : "Grottke"}, {"first" : "Sabina", "last" : "Jeschke"}, {"first" : "Thomas", "last" : "Richter"} ], "abstract": "We describe the implementation of and our experiences with a capstone course on wavelet based image compression held at the Berlin University of Technology in the years 2002 to 2006. This course has been designed as an ``integrated project'', which means that it combines lectures, seminar talks to be prepared and held by the students, and a programming part. The design goal of this course has been to provide all the necessary theoretical knowledge to understand the concepts behind image compression technologies, such as JPEG2000. We are also aiming at simulating the work-flow as found within an IT company as realistically as possible, preparing electrical engineers and computer scientists as well as possible for their professional life. This training does not only include the technical, but also the social skills required to successfully complete larger projects. The subject of image compression offers the advantage of requiring a solid knowledge on terms of information science such as entropy, distortion, quantization, Fourier and wavelet-transformation, but also offering a direct visual feedback of how these techniques perform. Therefore, we believe that image compression is an attractive topic to be used for a capstone course. Traditionally, a course would assign weekly programming exercises to the students; however, we believe this to be unsuitable for a capstone course as it does not simulate the work-flow of a professional software development team; furthermore, it does not require the degree of team-work we deem critical to modern software development. Thus, we divide students into groups of two to four people and assign each team to one sub-task of an image codec and provide some boiler-plate code of our own. Much to their astonishment, students soon find themselves spending a considerable amount of time with project management and coordination activities. That means, teams have to design interfaces and data structures to combine their efforts to create a working project, which adds an often underestimated social component to the course. With some guidance from the teachers, students have always been able to supply a working code at the end of the semester. Needless to say, the thrill of having a nontrivial working program at the end of the course is a major source of motivation for our students and adds much to the satisfaction and positive feedback we receive.", "bibtexKey": "grottke2007integrated" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2490b2a1a1d27f2c06c1d0e58003eec6c/thomasrichter", "tags" : [ "compression","image","myown","quality" ], "intraHash" : "490b2a1a1d27f2c06c1d0e58003eec6c", "interHash" : "5a476c6bb2cb3ebe1884d94be1d8f007", "label" : "A Global Image Fidelity Metric: Visual Distance and its Properties", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:37:38", "count" : 3, "pub-type": "inproceedings", "booktitle": "IEEE International Conference on Image Processing ICIP 2013","publisher":"IEEE","address":"Melbourne, Victoria, Australia", "year": "2013", "url": "http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6738076", "author": [ "Thomas Richter" ], "authors": [ {"first" : "Thomas", "last" : "Richter"} ], "pages": "369 - 373","abstract": "The purpose of full reference image quality indices like Mean Square Error (MSE) or SSIM is to predict the judgement of human observers in subjective quality assessment tasks. More advanced indices like SSIM or VIF are, however, rarely metrics in the strict sense, i.e. they don't define a distance between pairs of images that would describe how far these images are related. It was shown in a recent work, however, that SSIM can be \"integrated\" to such a global metric, in the following called Visual Distance, which behaves locally like SSIM, but globally like a distance in a curved space. It was also seen that the Visual Distance between two images can be interpreted as the number of almost invisible image deformations to transform one image into another. In this work, properties of Visual Distances will be discussed; these results will allow to extend the result from SSIM to its multi-scale variant MS-SSIM. It will also seen that human judgement will typically not define a metric, but it is conjectured that scores and Visual Distances are related by a monotonie Judgement Function. If so, it will be seen that the underlying Visual Distance can always be reconstructed from the scores up to a proportionality factor defined by the scale of the score.", "doi" : "10.1109/ICIP.2013.6738076", "bibtexKey": "richter2013global" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/26d19f20cc1e4c513119e11261962f53d/thomasrichter", "tags" : [ "compression","image","jpeg2000","myown" ], "intraHash" : "6d19f20cc1e4c513119e11261962f53d", "interHash" : "93ec1456c98c06c485225e11a908fbf0", "label" : "Faster JPEG2000 Encoding With Apriori Rate Allocation", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:37:16", "count" : 3, "pub-type": "inproceedings", "booktitle": "International MultiConference of Engineers and Computer Scientists 2007","address":"HongKong", "year": "2007", "url": "", "author": [ "Thomas Richter","Sven Grottke","Ruedi Seiler" ], "authors": [ {"first" : "Thomas", "last" : "Richter"}, {"first" : "Sven", "last" : "Grottke"}, {"first" : "Ruedi", "last" : "Seiler"} ], "bibtexKey": "richter2007faster" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2a9b2f26afb14ada9cd7787114235c2ce/thomasrichter", "tags" : [ "compression","image","myown","quality" ], "intraHash" : "a9b2f26afb14ada9cd7787114235c2ce", "interHash" : "139ae0d54747bad7001948782da3814d", "label" : "On the mDCT-PSNR Image Quality Index", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:36:55", "count" : 2, "pub-type": "inproceedings", "booktitle": "QoMEX 2009, First International Workshop on Quality of Multimedia Experience","address":"San Diego, CA, USA", "year": "2009", "url": "http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5246978", "author": [ "Thomas Richter" ], "authors": [ {"first" : "Thomas", "last" : "Richter"} ], "pages": "53-58","abstract": "Full reference image quality indices assign a quality\r\nindex to a pair of an undistorted reference image and a distorted\r\nimage to be assessed; the quality of the index itself is then defined\r\nby its ability to predict the outcome of subjective tests performed\r\nby human observers judging the quality of the same image pair.\r\nIn this article, a new DeT based image quality index is introduced\r\nwhose complexity is between that of algorithms like SSIM and\r\ncomplex, HVS-based algorithms like VDP. Detailed experiments\r\non the LIVE database show that the proposed algorithm performs\r\nbest close to or below the visual threshold, and outperforms there\r\nexisting algorithms like SSIM or VDP requiring only a mediocre\r\ncomplexity.", "isbn" : "978-1-4244-4370-3", "doi" : "10.1109/QOMEX.2009.5246978", "bibtexKey": "richter2009mdctpsnr" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2b9fb5203ee6289d01c9bf141d58f0112/thomasrichter", "tags" : [ "compression","image","jpeg","jpeg2000" ], "intraHash" : "b9fb5203ee6289d01c9bf141d58f0112", "interHash" : "02bc578b7deb2a49f6f5378afdca1dad", "label" : "Evaluation of Floating Point Image Compression", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:36:37", "count" : 3, "pub-type": "inproceedings", "booktitle": "QoMEX 2009, First International Workshop on Quality of Multimedia Experience","address":"San Diego, CA, USA", "year": "2009", "url": "http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=5246947", "author": [ "Thomas Richter" ], "authors": [ {"first" : "Thomas", "last" : "Richter"} ], "pages": "222-227","abstract": "Recently, compression of High Dynamic Range (HDR) photography gained\r\nattention in the standardization of the Microsoft HDPhoto compression scheme\r\nas JPEG-XR. While integer data of 16 bits/pixel (bpp) in scRGB color-space\r\ncan represent images up to a dynamic range of about 3.5 magnitudes in\r\nluminance --- a noteworthy improvement over the 1.6 magnitudes possible in\r\nsRGB --- even higher ranges are more efficiently represented by\r\nfloating-point number formats. However, traditional means to evaluate image\r\nquality are rarely suitable for such data: They are often only calibrated to\r\nlow-dynamic ranges (LDR) of 8bpp, and are not designed to take the\r\npeculiarities of floating-point data into account. In this work, we present\r\ntwo approaches to deal with this problem by introducing a (mathematical)\r\nquality index more suitable to floating point data related to\r\nSSIM~ssim,mssim, and by presenting an independent image quality\r\nevaluation framework that is able to apply LDR metrics to HDR data. The\r\npresented ideas are then tested on the HDPhoto floating point compression,\r\non a proprietary backwards compatible extension of JPEG~JPEGHDR and\r\non a proposed floating point compression scheme based on JPEG 2000~j2k\r\nthat is also proven to be optimal in the proposed quality index. It is then\r\nshown that both approaches, the proposed metric and PSNR in the LDR domain,\r\ndeliver comparable results.", "isbn" : "978-1-4244-4370-3", "doi" : "10.1109/QOMEX.2009.5246947", "bibtexKey": "richter2009evaluation" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/20fa2e309a2cd7a291449888471514bdf/thomasrichter", "tags" : [ "compression","cpu","gpu","image","low-complexity","myown" ], "intraHash" : "0fa2e309a2cd7a291449888471514bdf", "interHash" : "1c214f842d3f6bafc3be0b32e40c4d75", "label" : "Comparison of CPU and GPU Based Coding on Low-Complexity Algorithms for Display Signals", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:35:27", "count" : 3, "pub-type": "inproceedings", "booktitle": "Applications of Digital Image Processing XXXVI","publisher":"SPIE", "year": "2013", "url": "http://spie.org/Publications/Proceedings/Paper/10.1117/12.2022398", "author": [ "T. Richter","S. Simon" ], "authors": [ {"first" : "T.", "last" : "Richter"}, {"first" : "S.", "last" : "Simon"} ], "editor": [ "Andrew G. Tescher" ], "editors": [ {"first" : "Andrew G.", "last" : "Tescher"} ], "volume": "8856","pages": "14 pages","abstract": "Graphics Processing Units (GPUs) are freely programmable massively parallel general purpose processing units and thus offer the opportunity to off-load heavy computations from the CPU to the GPU. One application for GPU programming is image compression, where the massively parallel nature of GPUs promises high speed benefits. This article analyzes the predicaments of data-parallel image coding on the example of two high-throughput coding algorithms. The codecs discussed here were designed to answer a call from the Video Electronics Standards Association (VESA), and require only minimal buffering at encoder and decoder side while avoiding any pixel-based feedback loops limiting the operating frequency of hardware implementations. Comparing CPU and GPU implementations of the codes show that GPU based codes are usually not considerably faster, or perform only with less than ideal rate-distortion performance. Analyzing the details of this result provides theoretical evidence that for any coding engine either parts of the entropy coding and bit-stream build-up must remain serial, or rate-distortion penalties must be paid when offloading all computations on the GPU.", "isbn" : "9780819497062", "doi" : "10.1117/12.2022398", "bibtexKey": "richter2013comparison" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2a1f7eccccfcb4a53ea50e231ed54008f/thomasrichter", "tags" : [ "compression","design","image","learing","myown","wavelet" ], "intraHash" : "a1f7eccccfcb4a53ea50e231ed54008f", "interHash" : "1caa0c6de356f97aeda531d7f477dede", "label" : "Learning Abstract Information Theory on Visual Data: An Integrated Course on Wavelet-Based Image Compression", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:34:44", "count" : 2, "pub-type": "inproceedings", "booktitle": "2007 ASEE annual conference","address":"Honolulu, Hawaii", "year": "2007", "url": "", "author": [ "Sven Grottke","Thomas Richter" ], "authors": [ {"first" : "Sven", "last" : "Grottke"}, {"first" : "Thomas", "last" : "Richter"} ], "abstract": "We describe the implementation of and our experiences with a capstone course on wavelet based image compression held at the University of Technology Berlin in the years 2002 to 2006. This course has been designed as an ``integrated project'', which means that it combines lectures, seminar talks to be prepared and held by the students, and a programming part. \r\n\r\nThe design goal of this course has been to provide all the necessary theoretical knowledge to understand the concepts behind image compression technologies, such as JPEG2000. We are also aiming at simulating the work-flow as found within an IT company as realistically as possible, preparing electrical engineers and computer scientists as well as possible for their professional life. This training does not only include the technical, but also the social skills required to successfully complete larger projects.\r\n\r\nThe subject of image compression offers the advantage of requiring a solid knowledge on terms of information science such as entropy, distortion, quantization, Fourier and wavelet-transformation, but also offering a direct visual feedback of how these techniques perform. Therefore, we believe that image compression is an attractive topic to be used for a capstone course.\r\n\r\nTraditionally, a course would assign weekly programming exercises to the students; however, we believe this to be unsuitable for a capstone course as it does not simulate the work-flow of a professional software development team; furthermore, it does not require the degree of team-work we deem critical to modern software development. Thus, we divide students into groups of two to four people and assign each team to one sub-task of an image codec and provide some boiler-plate code of our own. Much to their astonishment, students soon find themselves spending a considerable amount of time with project management and coordination activities. That means, teams have to design interfaces and data structures to combine their efforts to create a working project, which adds an often underestimated social component to the course. With some guidance from the teachers, students have always been able to supply a working code at the end of the semester. Needless to say, the thrill of having a nontrivial working program at the end of the course is a major source of motivation for our students and adds much to the satisfaction and positive feedback we receive.", "bibtexKey": "grottke2007learning" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2f2384d59679a892e3b00bdaef89ed8ae/thomasrichter", "tags" : [ "compression","image","jpeg","jpeg-xt","myown" ], "intraHash" : "f2384d59679a892e3b00bdaef89ed8ae", "interHash" : "a167e09e56bc18898e351afd1dc39e70", "label" : "Rate Allocation in a Two Quantizer Coding System", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:34:07", "count" : 3, "pub-type": "inproceedings", "booktitle": "Data Compression Conference (DCC), 2014","publisher":"IEEE","address":"Snowbird, UT", "year": "2014", "url": "http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6824416", "author": [ "Thomas Richter" ], "authors": [ {"first" : "Thomas", "last" : "Richter"} ], "pages": "83 - 92","abstract": "The issue of backwards compatible image and video coding gained some attention in both MPEG and JPEG, let it be as extension for HEVC, let it be as the JPEG XT standardization initiative of the SC29WG1 committee. The coding systems work all on the principle of a base layer, perating in the low-dynamic range regime, using a one-mapped version of the HDR material as input, and an extension layer invisible to legacy applications. The extension layer allows implementations conforming to the full standard to reconstruct the original image in the high-dynamic range regime. What is also common to all approaches is the rate-allocation problem: How can one split the rate between base and extension layer to ensure optimal coding? In this work, an explicit answer is derived for a simplified model of a two-layer compression system in the high bit-rate approximation. For a HDR to LDR tone mapping that approximates the well-known sRGB non-linearity of gamma = 2.4 and a Laplacian probability density function, explicit results in the form of the Lambert-W-function are derived. The theoretical results are then verified in experiments using a JPEG XT demo implementation.", "doi" : "10.1109/DCC.2014.9", "bibtexKey": "richter2014allocation" } , { "type" : "Publication", "id" : "https://puma.ub.uni-stuttgart.de/bibtex/2cdc307bfd22fc8d6cb0421d015600449/thomasrichter", "tags" : [ "compression","image" ], "intraHash" : "cdc307bfd22fc8d6cb0421d015600449", "interHash" : "25acb35f161596ef1f5c95f0d77bc1ea", "label" : "High Throughput Coding of Video Signals", "user" : "thomasrichter", "description" : "", "date" : "2016-03-10 09:18:49", "changeDate" : "2016-03-10 08:33:49", "count" : 2, "pub-type": "inproceedings", "booktitle": "Data Compression Conference (DCC)","publisher":"IEEE","address":"Snowbird, UT", "year": "2013", "url": "http://ieeexplore.ieee.org/xpl/articleDetails.jsp?arnumber=6543127", "author": [ "Thomas Richter" ], "authors": [ {"first" : "Thomas", "last" : "Richter"} ], "pages": "517","abstract": "As the resolution of monitors and TVs continue to increase, the available bandwidth between host system and monitor becomes more and more a bottleneck. The Video Electronics Standards Association (VESA) is currently developing standards for screen resolutions beyond 4K and, facing the problem of not having enough bandwidth available on traditional copper wires, contacted the JPEG to develop a low complexity, high-throughput still image coder for lossy transmission of video signals. This article describes two approaches to address this predicament, a simple SPIHT based coded and a Hadamard based embedded codec requiring only minimal buffering at encoder and decoder side, and avoiding any pixel-based feedback loops limiting the operating frequency of hardware implementations. Analyzing the details of both implementations reveals an interesting connection between run-length coding, as found in the progressive mode of traditional JPEG coding, and SPIHT/EZW coding - a technique popular in wavelet based compression techniques.", "isbn" : "978-1-4673-6037-1", "doi" : "10.1109/DCC.2013.96", "bibtexKey": "richter2013throughput" } ] }