[ { "id": "knecht_2013_RSM", "type_id": "phdthesis", "tu_id": null, "repositum_id": null, "title": "Reciprocal Shading for Mixed Reality", "date": "2013-12", "abstract": "Reciprocal shading for mixed reality aims to integrate virtual objects into real environments in a way that they are in the ideal case indistinguishable from real objects. It is therefore an attractive technology for architectural visualizations, product visualizations and for cultural heritage sites, where virtual objects should be seamlessly merged with real ones. Due to the improved performance of recent graphics hardware, real-time global illumination algorithms are feasible for mixed-reality applications, and thus more and more researchers address realistic rendering for mixed reality.\n\nThe goal of this thesis is to provide algorithms which improve the visual plausibility of virtual objects in mixed-reality applications. Our contributions are as follows:\n\nFirst, we present five methods to reconstruct the real surrounding environment. In particular,\nwe present two methods for geometry reconstruction, a method for material estimation at interactive frame rates and two methods to reconstruct the color mapping characteristics of the video see-through camera.\n\nSecond, we present two methods to improve the visual appearance of virtual objects. The first, called differential instant radiosity, combines differential rendering with a global illumination method called instant radiosity to simulate reciprocal shading effects such as shadowing and indirect illumination between real and virtual objects. The second method focuses on the visual\nplausible rendering of reflective and refractive objects. The high-frequency lighting effects caused by these objects are also simulated with our method.\n\nThe third part of this thesis presents two user studies which evaluate the influence of the presented\nrendering methods on human perception. The first user study measured task performance with respect to the rendering mode, and the second user study was set up as a web survey where\nparticipants had to choose which of two presented images, showing mixed-reality scenes, they preferred.", "authors_et_al": false, "substitute": null, "main_image": null, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 736 ], "co_supervisor": [ 1299 ], "date_end": "2013-12", "date_start": "2009-08", "reviewer_1": [ 193 ], "reviewer_2": [ 1299 ], "rigorosum": "2013-12-19", "supervisor": [ 193 ], "research_areas": [ "Rendering" ], "keywords": [], "weblinks": [], "files": [ { "description": null, "filetitle": "Thesis", "main_file": false, "use_in_gallery": false, "access": "public", "name": "knecht_2013_RSM-Thesis.pdf", "type": "application/pdf", "size": 69715044, "path": "Publication:knecht_2013_RSM", "url": "https://www.cg.tuwien.ac.at/research/publications/2013/knecht_2013_RSM/knecht_2013_RSM-Thesis.pdf", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2013/knecht_2013_RSM/knecht_2013_RSM-Thesis:thumb{{size}}.png" } ], "projects_workgroups": [ "RESHADE" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2013/knecht_2013_RSM/", "__class": "Publication" }, { "id": "knecht_martin_2013_ReflRefrObjsMR", "type_id": "journalpaper", "tu_id": null, "repositum_id": null, "title": "Reflective and Refractive Objects for Mixed Reality", "date": "2013-03", "abstract": "In this paper, we present a novel rendering method which integrates reflective or refractive objects into a differential instant radiosity (DIR) framework usable for mixed-reality (MR) applications. This kind of objects are very special from the light interaction point of view, as they reflect and refract incident rays. Therefore they may cause high-frequency lighting effects known as caustics. Using instant-radiosity (IR) methods to approximate these high-frequency lighting effects would require a large amount of virtual point lights (VPLs) and is therefore not desirable due to real-time constraints. Instead, our approach combines differential instant radiosity with three other methods. One method handles more accurate reflections compared to simple cubemaps by using impostors. Another method is able to calculate two refractions in real-time, and the third method uses small quads to create caustic effects. Our proposed method replaces parts in light paths that belong to reflective or refractive objects using these three methods and thus tightly integrates into DIR. In contrast to previous methods which introduce reflective or refractive objects into MR scenarios, our method produces caustics that also emit additional indirect light. The method runs at real-time frame rates, and the results show that reflective and refractive objects with caustics improve the overall impression for MR scenarios.", "authors_et_al": false, "substitute": null, "main_image": { "description": null, "filetitle": "image", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1024, "image_height": 768, "name": "knecht_martin_2013_ReflRefrObjsMR-image.jpg", "type": "image/jpeg", "size": 454801, "path": "Publication:knecht_martin_2013_ReflRefrObjsMR", "url": "https://www.cg.tuwien.ac.at/research/publications/2013/knecht_martin_2013_ReflRefrObjsMR/knecht_martin_2013_ReflRefrObjsMR-image.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2013/knecht_martin_2013_ReflRefrObjsMR/knecht_martin_2013_ReflRefrObjsMR-image:thumb{{size}}.png" }, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 736, 237, 1011, 193 ], "date_from": "2013-03-18", "date_to": "2013-03-20", "event": "IEEE Virtual Reality 2013", "issn": "1077-2626", "journal": "IEEE Transactions on Visualization and Computer Graphics (Proceedings of IEEE VR 2013)", "lecturer": [ 736 ], "location": "Orlando, Florida", "number": "4", "pages_from": "576", "pages_to": "582", "volume": "19", "research_areas": [ "Rendering" ], "keywords": [ "Mixed Reality", "Caustics", "Reflections", "Refractions" ], "weblinks": [ { "href": "http://dx.doi.org/10.1109/TVCG.2013.39", "caption": null, "description": null, "main_file": 0 } ], "files": [ { "description": null, "filetitle": "image", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1024, "image_height": 768, "name": "knecht_martin_2013_ReflRefrObjsMR-image.jpg", "type": "image/jpeg", "size": 454801, "path": "Publication:knecht_martin_2013_ReflRefrObjsMR", "url": "https://www.cg.tuwien.ac.at/research/publications/2013/knecht_martin_2013_ReflRefrObjsMR/knecht_martin_2013_ReflRefrObjsMR-image.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2013/knecht_martin_2013_ReflRefrObjsMR/knecht_martin_2013_ReflRefrObjsMR-image:thumb{{size}}.png" }, { "description": "Slides", "filetitle": "Slides", "main_file": true, "use_in_gallery": false, "access": "public", "name": "knecht_martin_2013_ReflRefrObjsMR-Slides.pptx", "type": "application/zip", "size": 16711972, "path": "Publication:knecht_martin_2013_ReflRefrObjsMR", "url": "https://www.cg.tuwien.ac.at/research/publications/2013/knecht_martin_2013_ReflRefrObjsMR/knecht_martin_2013_ReflRefrObjsMR-Slides.pptx", "thumb_image_sizes": [] } ], "projects_workgroups": [ "RESHADE" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2013/knecht_martin_2013_ReflRefrObjsMR/", "__class": "Publication" }, { "id": "knecht_martin_2012_RSMR", "type_id": "journalpaper_notalk", "tu_id": null, "repositum_id": null, "title": "Reciprocal Shading for Mixed Reality", "date": "2012-11", "abstract": "In this paper we present a novel plausible rendering method for mixed reality systems, which is useful for many real-life application scenarios, like architecture, product visualization or edutainment. To allow virtual objects to seamlessly blend into the real environment, the real lighting conditions and the mutual illumination effects between real and virtual objects must be considered, while maintaining interactive frame rates. The most important such effects are indirect illumination and shadows cast between real and virtual objects.\n\nOur approach combines Instant Radiosity and Differential Rendering. In contrast to some previous solutions, we only need to render the scene once in order to find the mutual effects of virtual and real scenes. In addition, we avoid artifacts like double shadows or inconsistent color bleeding which appear in previous work. The dynamic real illumination is derived from the image stream of a fish-eye lens camera. The scene gets illuminated by virtual point lights, which use imperfect shadow maps to calculate visibility. A sufficiently fast scene reconstruction is done at run-time with Microsoft's Kinect sensor. Thus a time-consuming manual pre-modeling step of the real scene is not necessary. Our results show that the presented method highly improves the illusion in mixed-reality applications and significantly diminishes the artificial look of virtual objects superimposed onto real scenes.", "authors_et_al": false, "substitute": null, "main_image": { "description": "GraphicalAbstract", "filetitle": "image", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1328, "image_height": 531, "name": "knecht_martin_2012_RSMR-image.jpg", "type": "image/jpeg", "size": 441789, "path": "Publication:knecht_martin_2012_RSMR", "url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_RSMR/knecht_martin_2012_RSMR-image.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_RSMR/knecht_martin_2012_RSMR-image:thumb{{size}}.png" }, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 736, 237, 326, 193 ], "issn": "0097-8493", "journal": "Computers & Graphics", "number": "7", "pages_from": "846", "pages_to": "856", "volume": "36", "research_areas": [ "Rendering" ], "keywords": [ "Differential rendering", "Reconstruction", "Instant radiosity", "Microsoft Kinect", "Real-time global illumination", "Mixed reality" ], "weblinks": [ { "href": "http://www.sciencedirect.com/science/article/pii/S0097849312001148", "caption": null, "description": null, "main_file": 0 } ], "files": [ { "description": null, "filetitle": "draft", "main_file": true, "use_in_gallery": false, "access": "public", "name": "knecht_martin_2012_RSMR-draft.pdf", "type": "application/pdf", "size": 15824633, "path": "Publication:knecht_martin_2012_RSMR", "url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_RSMR/knecht_martin_2012_RSMR-draft.pdf", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_RSMR/knecht_martin_2012_RSMR-draft:thumb{{size}}.png" }, { "description": "GraphicalAbstract", "filetitle": "image", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1328, "image_height": 531, "name": "knecht_martin_2012_RSMR-image.jpg", "type": "image/jpeg", "size": 441789, "path": "Publication:knecht_martin_2012_RSMR", "url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_RSMR/knecht_martin_2012_RSMR-image.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_RSMR/knecht_martin_2012_RSMR-image:thumb{{size}}.png" } ], "projects_workgroups": [ "RESHADE" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_RSMR/", "__class": "Publication" }, { "id": "knecht_martin_2012_BRDFEstimation", "type_id": "journalpaper", "tu_id": null, "repositum_id": null, "title": "Interactive BRDF Estimation for Mixed-Reality Applications", "date": "2012-06", "abstract": "Recent methods in augmented reality allow simulating mutual light interactions between real and virtual objects. These methods are able to embed virtual objects in a more sophisticated way than previous methods. However, their main drawback is that they need a virtual representation of the real scene to be augmented in the form of geometry and material properties. In the past, this representation had to be modeled in advance, which is very time consuming and only allows for static scenes.\n\nWe propose a method that reconstructs the surrounding environment and estimates its Bidirectional Reflectance Distribution Function (BRDF) properties at runtime without any preprocessing. By using the Microsoft Kinect sensor and an optimized hybrid CPU & GPU-based BRDF estimation method, we are able to achieve interactive frame rates. The proposed method was integrated into a differential instant radiosity rendering system to demonstrate its feasibility.", "authors_et_al": false, "substitute": null, "main_image": { "description": "Kinect Input", "filetitle": "KinectInput", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1312, "image_height": 480, "name": "knecht_martin_2012_BRDFEstimation-KinectInput.jpg", "type": "image/jpeg", "size": 396166, "path": "Publication:knecht_martin_2012_BRDFEstimation", "url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_BRDFEstimation/knecht_martin_2012_BRDFEstimation-KinectInput.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_BRDFEstimation/knecht_martin_2012_BRDFEstimation-KinectInput:thumb{{size}}.png" }, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 736, 920, 237, 193 ], "date_from": "2012-06-25", "date_to": "2012-06-28", "event": "WSCG 2012", "issn": "1213-6972", "journal": "Journal of WSCG", "lecturer": [ 736 ], "location": "Plzen, Czech Republic", "number": "1", "pages_from": "47", "pages_to": "56", "volume": "20", "research_areas": [ "Rendering" ], "keywords": [ "Augmented Reality", "BRDF Estimation", "Reconstruction" ], "weblinks": [], "files": { "0": { "description": "Result", "filetitle": "FinalImage", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 640, "image_height": 480, "name": "knecht_martin_2012_BRDFEstimation-FinalImage.jpg", "type": "image/jpeg", "size": 398907, "path": "Publication:knecht_martin_2012_BRDFEstimation", "url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_BRDFEstimation/knecht_martin_2012_BRDFEstimation-FinalImage.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_BRDFEstimation/knecht_martin_2012_BRDFEstimation-FinalImage:thumb{{size}}.png" }, "1": { "description": "Kinect Input", "filetitle": "KinectInput", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1312, "image_height": 480, "name": "knecht_martin_2012_BRDFEstimation-KinectInput.jpg", "type": "image/jpeg", "size": 396166, "path": "Publication:knecht_martin_2012_BRDFEstimation", "url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_BRDFEstimation/knecht_martin_2012_BRDFEstimation-KinectInput.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_BRDFEstimation/knecht_martin_2012_BRDFEstimation-KinectInput:thumb{{size}}.png" }, "2": { "description": null, "filetitle": "paper", "main_file": true, "use_in_gallery": false, "access": "public", "name": "knecht_martin_2012_BRDFEstimation-paper.pdf", "type": "application/pdf", "size": 1057380, "path": "Publication:knecht_martin_2012_BRDFEstimation", "url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_BRDFEstimation/knecht_martin_2012_BRDFEstimation-paper.pdf", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_BRDFEstimation/knecht_martin_2012_BRDFEstimation-paper:thumb{{size}}.png" }, "4": { "description": null, "filetitle": "video", "main_file": false, "use_in_gallery": false, "access": "public", "name": "knecht_martin_2012_BRDFEstimation-video.mpg", "type": "text/plain", "size": 10586468, "path": "Publication:knecht_martin_2012_BRDFEstimation", "url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_BRDFEstimation/knecht_martin_2012_BRDFEstimation-video.mpg", "thumb_image_sizes": [] } }, "projects_workgroups": [ "RESHADE" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2012/knecht_martin_2012_BRDFEstimation/", "__class": "Publication" }, { "id": "knecht-2011-CBCM", "type_id": "inproceedings", "tu_id": null, "repositum_id": null, "title": "Adaptive Camera-Based Color Mapping For Mixed-Reality Applications", "date": "2011-10", "abstract": "We present a novel adaptive color mapping method for virtual objects in mixed-reality environments. In several mixed-reality applications, added virtual objects should be visually indistinguishable from real objects. Recent mixed-reality methods use global-illumination algorithms to approach this goal. However, simulating the light distribution is not enough for visually plausible images. Since the observing camera has its very own transfer function from real-world radiance values to RGB colors, virtual objects look artificial just because their rendered colors do not match with those of the camera.\n\nOur approach combines an on-line camera characterization method with a heuristic to map colors of virtual objects to colors as they would be seen by the observing camera. Previous tone-mapping functions were not designed for use in mixed-reality systems and thus did not take the camera-specific behavior into account. In contrast, our method takes the camera into account and thus can also handle changes of its parameters during runtime. The results show that virtual objects look visually more plausible than by just applying tone-mapping operators.", "authors_et_al": false, "substitute": null, "main_image": { "description": "Shows color adaption of virtual book and colorchart on the left", "filetitle": "Image 1", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1024, "image_height": 767, "name": "knecht-2011-CBCM-Image 1.jpg", "type": "image/jpeg", "size": 561780, "path": "Publication:knecht-2011-CBCM", "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Image 1.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Image 1:thumb{{size}}.png" }, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 736, 237, 190, 193 ], "booktitle": "Proceedings of the 2011 IEEE International Symposium on Mixed and Augmented Reality (ISMAR 2011)", "date_from": "2011-10-26", "date_to": "2011-10-29", "isbn": "978-1-4577-2183-0 ", "location": "Basel, Switzerland", "note": "E-ISBN: 978-1-4577-2184-7", "pages_from": "165", "pages_to": "168", "publisher": "IEEE/IET Electronic Library (IEL), IEEE-Wiley eBooks Library, VDE VERLAG Conference Proceedings", "research_areas": [ "Rendering" ], "keywords": [ "Color Matching", "Differential Rendering", "Mixed Reality", "Tone Mapping" ], "weblinks": [], "files": { "0": { "description": "Shows color adaption of virtual book and colorchart on the left", "filetitle": "Image 1", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1024, "image_height": 767, "name": "knecht-2011-CBCM-Image 1.jpg", "type": "image/jpeg", "size": 561780, "path": "Publication:knecht-2011-CBCM", "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Image 1.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Image 1:thumb{{size}}.png" }, "1": { "description": "Shows color adaption of virtual book and colorchart on the left", "filetitle": "Image", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1024, "image_height": 767, "name": "knecht-2011-CBCM-Image.jpg", "type": "image/jpeg", "size": 301091, "path": "Publication:knecht-2011-CBCM", "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Image.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Image:thumb{{size}}.png" }, "2": { "description": "Conference Paper", "filetitle": "Preprint", "main_file": true, "use_in_gallery": false, "access": "public", "name": "knecht-2011-CBCM-Preprint.pdf", "type": "application/pdf", "size": 25284280, "path": "Publication:knecht-2011-CBCM", "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Preprint.pdf", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Preprint:thumb{{size}}.png" }, "4": { "description": "Video results", "filetitle": "Video", "main_file": true, "use_in_gallery": false, "access": "public", "preview_image_width": 640, "preview_image_height": 480, "name": "knecht-2011-CBCM-Video.avi", "type": "video/x-msvideo", "size": 36674560, "path": "Publication:knecht-2011-CBCM", "preview_name": "knecht-2011-CBCM-Video:preview.png", "preview_type": "image/jpeg", "preview_size": 5344, "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Video.avi", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Video:thumb{{size}}.png", "video_mp4": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/knecht-2011-CBCM-Video:video.mp4" } }, "projects_workgroups": [ "RESHADE" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht-2011-CBCM/", "__class": "Publication" }, { "id": "KUE11", "type_id": "inproceedings", "tu_id": null, "repositum_id": null, "title": "BRDF approximation and estimation for Augmented Reality", "date": "2011-10", "abstract": "In Augmented Reality applications it is important to have a good description of the surfaces of real objects if a consistent shading between real and virtual object is required. If such a description of a surface is not vailable it has to be estimated or approximated. In our paper we will present certain methods that deal\nwith real-time bi-directional reflectance distribution function\n(BRDF) approximation in augmented reality. Of course an important thing to discuss is whether the applications we present all work in real-time and compute good (and real)looking results.\nThere are different methods on how to achieve this goal. All of the methods we are going to present work via image based lighting and some require a 3D polygonal mesh representation\nof the object whose BRDF shall be approximated. Some methods estimate the BRDF parameters via error values and\nprovide results at each iteration.", "authors_et_al": false, "substitute": null, "main_image": null, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 841, 736, 237 ], "booktitle": "15th International Conference on System Theory, Control and Computing", "date_from": "2011-10-14", "date_to": "2011-10-16", "lecturer": [ 841 ], "location": "Sinaia, Romania", "organization": "\"Gheorghe Asachi\" Technical University of Iasi, Faculty of Automatic Control and Computer Engineering", "pages_from": "318", "pages_to": "324", "research_areas": [ "Rendering" ], "keywords": [ "Mixed Reality", "BRDF Estimation" ], "weblinks": [], "files": [ { "description": null, "filetitle": "Paper", "main_file": true, "use_in_gallery": false, "access": "public", "name": "KUE11-Paper.pdf", "type": "application/pdf", "size": 411981, "path": "Publication:KUE11", "url": "https://www.cg.tuwien.ac.at/research/publications/2011/KUE11/KUE11-Paper.pdf", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2011/KUE11/KUE11-Paper:thumb{{size}}.png" } ], "projects_workgroups": [ "RESHADE" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2011/KUE11/", "__class": "Publication" }, { "id": "knecht_martin-2011-FPSPAR", "type_id": "inproceedings", "tu_id": null, "repositum_id": null, "title": "A Framework For Perceptual Studies In Photorealistic Augmented Reality", "date": "2011-03", "abstract": "In photorealistic augmented reality virtual objects are integrated in the real world in a seamless visual manner. To obtain a perfect visual augmentation these objects must be rendered indistinguishable from real objects and should be perceived as such. In this paper we propose a research test bed framework to study the different unresolved perceptual issues in photorealistic augmented reality and its application to different disciplines. The framework computes a global illumination approximation in real-time and therefore leverages a new class of experimental research topics.", "authors_et_al": false, "substitute": null, "main_image": { "description": "Shows a participant performing the experiment", "filetitle": "image2", "main_file": false, "use_in_gallery": false, "access": "public", "image_width": 1000, "image_height": 664, "name": "knecht_martin-2011-FPSPAR-image2.JPG", "type": "image/jpeg", "size": 459755, "path": "Publication:knecht_martin-2011-FPSPAR", "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht_martin-2011-FPSPAR/knecht_martin-2011-FPSPAR-image2.JPG", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht_martin-2011-FPSPAR/knecht_martin-2011-FPSPAR-image2:thumb{{size}}.png" }, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 736, 917, 237, 193, 916 ], "booktitle": "Proceedings of the 3rd IEEE VR 2011 Workshop on Perceptual Illusions in Virtual Environments", "date_from": "2011-03-19", "date_to": "2011-03-19", "editor": "Frank Steinicke, Pete Willemsen", "lecturer": [ 736 ], "location": "Singapore", "pages_from": "27", "pages_to": "32", "research_areas": [ "Rendering" ], "keywords": [ "photorealistic augmented reality", "real-time global illumination", "human perception" ], "weblinks": [], "files": [ { "description": "This image shows the augmented scene of our experiment including shadows and color bleeding", "filetitle": "image", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 791, "image_height": 591, "name": "knecht_martin-2011-FPSPAR-image.jpg", "type": "image/jpeg", "size": 353116, "path": "Publication:knecht_martin-2011-FPSPAR", "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht_martin-2011-FPSPAR/knecht_martin-2011-FPSPAR-image.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht_martin-2011-FPSPAR/knecht_martin-2011-FPSPAR-image:thumb{{size}}.png" }, { "description": "Shows the green box and the markers for hand tracking", "filetitle": "image1", "main_file": false, "use_in_gallery": false, "access": "public", "image_width": 1000, "image_height": 664, "name": "knecht_martin-2011-FPSPAR-image1.JPG", "type": "image/jpeg", "size": 313207, "path": "Publication:knecht_martin-2011-FPSPAR", "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht_martin-2011-FPSPAR/knecht_martin-2011-FPSPAR-image1.JPG", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht_martin-2011-FPSPAR/knecht_martin-2011-FPSPAR-image1:thumb{{size}}.png" }, { "description": "Shows a participant performing the experiment", "filetitle": "image2", "main_file": false, "use_in_gallery": false, "access": "public", "image_width": 1000, "image_height": 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"https://www.cg.tuwien.ac.at/research/publications/2011/knecht_martin-2011-FPSPAR/knecht_martin-2011-FPSPAR-image3:thumb{{size}}.png" }, { "description": "A Framework For Perceptual Studies In Photorealistic Augmented Reality", "filetitle": "paper", "main_file": true, "use_in_gallery": false, "access": "public", "name": "knecht_martin-2011-FPSPAR-paper.pdf", "type": "application/pdf", "size": 394970, "path": "Publication:knecht_martin-2011-FPSPAR", "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht_martin-2011-FPSPAR/knecht_martin-2011-FPSPAR-paper.pdf", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht_martin-2011-FPSPAR/knecht_martin-2011-FPSPAR-paper:thumb{{size}}.png" } ], "projects_workgroups": [ "RESHADE" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2011/knecht_martin-2011-FPSPAR/", "__class": "Publication" }, { "id": "knecht_martin_2010_DIR", "type_id": "inproceedings", "tu_id": null, "repositum_id": null, "title": "Differential Instant Radiosity for Mixed Reality", "date": "2010-10", "abstract": "In this paper we present a novel plausible realistic rendering method for mixed reality systems, which is useful for many real life application scenarios, like architecture, product visualization or edutainment. To allow virtual objects to seamlessly blend into the real environment, the real lighting conditions and the mutual illumination effects between real and virtual objects must be considered, while maintaining interactive frame rates (20-30fps). The most important such effects are indirect illumination and shadows cast between real and virtual objects.\n\nOur approach combines Instant Radiosity and Differential Rendering. In contrast to some previous solutions, we only need to render the scene once in order to find the mutual effects of virtual and real scenes. The dynamic real illumination is derived from the image stream of a fish-eye lens camera. We describe a new method to assign virtual point lights to multiple primary light sources, which can be real or virtual. We use imperfect shadow maps for calculating illumination from virtual point lights and have significantly improved their accuracy by taking the surface normal of a shadow caster into account. Temporal coherence is exploited to reduce flickering artifacts. Our results show that the presented method highly improves the illusion in mixed reality applications and significantly diminishes the artificial look of virtual objects superimposed onto real scenes.", "authors_et_al": false, "substitute": null, "main_image": { "description": null, "filetitle": "image0", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1019, "image_height": 763, "name": "knecht_martin_2010_DIR-image0.jpg", "type": "image/jpeg", "size": 461015, "path": "Publication:knecht_martin_2010_DIR", "url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-image0.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-image0:thumb{{size}}.png" }, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 736, 237, 326, 190, 193 ], "booktitle": "Proceedings of the 2010 IEEE International Symposium on Mixed and Augmented Reality (ISMAR 2010)", "date_from": "2010-10-13", "date_to": "2010-10-16", "lecturer": [ 736 ], "location": "Seoul", "note": "Best Paper Award!", "pages_from": "99", "pages_to": "107", "research_areas": [ "Rendering" ], "keywords": [ "Instant Radiosity", "Differential Rendering", "Real-time Global Illumination", "Mixed Reality" ], "weblinks": [], "files": { "0": { "description": null, "filetitle": "image0", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1019, "image_height": 763, "name": "knecht_martin_2010_DIR-image0.jpg", "type": "image/jpeg", "size": 461015, "path": "Publication:knecht_martin_2010_DIR", "url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-image0.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": 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"knecht_martin_2010_DIR-image2.jpg", "type": "image/jpeg", "size": 1430039, "path": "Publication:knecht_martin_2010_DIR", "url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-image2.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-image2:thumb{{size}}.png" }, "3": { "description": "Color bleeding from real on virtual object", "filetitle": "image3", "main_file": false, "use_in_gallery": false, "access": "public", "image_width": 1022, "image_height": 765, "name": "knecht_martin_2010_DIR-image3.jpg", "type": "image/jpeg", "size": 1455524, "path": "Publication:knecht_martin_2010_DIR", "url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-image3.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-image3:thumb{{size}}.png" }, "4": { "description": "Differential Instant Radiosity for Mixed Reality", "filetitle": "paper", "main_file": true, "use_in_gallery": false, "access": "public", "name": "knecht_martin_2010_DIR-paper.pdf", "type": "application/pdf", "size": 19340106, "path": "Publication:knecht_martin_2010_DIR", "url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-paper.pdf", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-paper:thumb{{size}}.png" }, "6": { "description": "Video Results", "filetitle": "Video", "main_file": false, "use_in_gallery": false, "access": "public", "preview_image_width": 640, "preview_image_height": 480, "name": "knecht_martin_2010_DIR-Video.avi", "type": "video/x-msvideo", "size": 8766976, "path": "Publication:knecht_martin_2010_DIR", "preview_name": "knecht_martin_2010_DIR-Video:preview.png", "preview_type": "image/jpeg", "preview_size": 5344, "url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-Video.avi", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-Video:thumb{{size}}.png", "video_mp4": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/knecht_martin_2010_DIR-Video:video.mp4" } }, "projects_workgroups": [ "RESHADE" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2010/knecht_martin_2010_DIR/", "__class": "Publication" }, { "id": "knecht-2009-MKN", "type_id": "masterthesis", "tu_id": null, "repositum_id": null, "title": "Real-Time Global Illumination Using Temporal Coherence", "date": "2009-07", "abstract": "The goal of this thesis is to produce plausible global illumination in real time using temporal coherence. While direct illumination combined with precomputed static global illumination is widely used in today’s computer games and 3D applications, real-time global illumination that supports arbitrary dynamic scenes and light setups is still an active area of research. This master thesis gives an introduction to global illumination and discusses various methods that have been developed. However, since most of the existing methods need some kind of precomputation to calculate global illumination in real time, they also introduce limitations like static light, scenes or view points. Furthermore other algorithms are not suitable for the capabilities of current graphics hardware or are simply fake approaches. The core of this thesis is an improved version of the instant radiosity and imperfect\r\nshadow maps algorithm that reuses illumination information from previous\r\nframes. The previous approaches needed a high number of so called virtual point\r\nlights to get convincing results, whereas our method achieves visually pleasing results with only a few virtual point lights. As a second extension to the base algorithms we introduce a new method to compute multiple light bounces. In this\r\nmethod the fill rate is drastically reduced and therefore computation time is much lower than in previous aproaches.", "authors_et_al": false, "substitute": null, "main_image": { "description": "", "filetitle": "image", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1024, "image_height": 768, "name": "knecht-2009-MKN-image.jpg", "type": "image/jpeg", "size": 273991, "path": "Publication:knecht-2009-MKN", "url": "https://www.cg.tuwien.ac.at/research/publications/2009/knecht-2009-MKN/knecht-2009-MKN-image.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2009/knecht-2009-MKN/knecht-2009-MKN-image:thumb{{size}}.png" }, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 736 ], "diploma_examina": "2009-07-28", "supervisor": [ 193, 326 ], "research_areas": [], "keywords": [ "Real Time Rendering", "Global Illumination", "Instant Radiosity", "Temporal Coherence" ], "weblinks": [], "files": [ { "description": "", "filetitle": "image", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 1024, "image_height": 768, "name": "knecht-2009-MKN-image.jpg", "type": "image/jpeg", "size": 273991, "path": "Publication:knecht-2009-MKN", "url": "https://www.cg.tuwien.ac.at/research/publications/2009/knecht-2009-MKN/knecht-2009-MKN-image.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2009/knecht-2009-MKN/knecht-2009-MKN-image:thumb{{size}}.png" }, { "description": "", "filetitle": "poster", "main_file": true, "use_in_gallery": false, "access": "public", "name": "knecht-2009-MKN-poster.pdf", "type": "application/pdf", "size": 1753507, "path": "Publication:knecht-2009-MKN", "url": "https://www.cg.tuwien.ac.at/research/publications/2009/knecht-2009-MKN/knecht-2009-MKN-poster.pdf", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2009/knecht-2009-MKN/knecht-2009-MKN-poster:thumb{{size}}.png" }, { "description": "", "filetitle": "thesis", "main_file": true, "use_in_gallery": false, "access": "public", "name": "knecht-2009-MKN-thesis.pdf", "type": "application/pdf", "size": 24255873, "path": "Publication:knecht-2009-MKN", "url": "https://www.cg.tuwien.ac.at/research/publications/2009/knecht-2009-MKN/knecht-2009-MKN-thesis.pdf", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2009/knecht-2009-MKN/knecht-2009-MKN-thesis:thumb{{size}}.png" } ], "projects_workgroups": [ "rend" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2009/knecht-2009-MKN/", "__class": "Publication" }, { "id": "knecht-2007-ao", "type_id": "techreport", "tu_id": null, "repositum_id": null, "title": "State of the Art Report on Ambient Occlusion", "date": "2007-11", "abstract": "Ambient occlusion is a shading method which takes light occluded\nby geometry into account. Since this technique needs to integrate\nover a hemisphere it was first only used in offline rendering tools.\nHowever, the increasing resources of modern graphics hardware,\nenable us to render ambient occlusion in realtime. The goal of this\nreport is to describe the most popular techniques with respect to\nrealtime rendering. First we introduce how ambient occlusion is\ndefined and then we will explain and categorize the presented techniques.\n", "authors_et_al": false, "substitute": null, "main_image": null, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 736 ], "number": "TR-186-2-07-13", "research_areas": [ "Rendering" ], "keywords": [ "ambient occlusion", " global illumination", "real time" ], "weblinks": [], "files": [ { "description": null, "filetitle": "paper", "main_file": false, "use_in_gallery": false, "access": "public", "name": "knecht-2007-ao-paper.pdf", "type": "application/pdf", "size": 3440621, "path": "Publication:knecht-2007-ao", "url": "https://www.cg.tuwien.ac.at/research/publications/2007/knecht-2007-ao/knecht-2007-ao-paper.pdf", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2007/knecht-2007-ao/knecht-2007-ao-paper:thumb{{size}}.png" } ], "projects_workgroups": [ "rend" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2007/knecht-2007-ao/", "__class": "Publication" }, { "id": "Knecht_Schwaerzler_2008_ash", "type_id": "studentproject", "tu_id": null, "repositum_id": null, "title": "Soft Shadows Using Adaptive Subdivision", "date": "2007", "abstract": "We render soft shadows using shadow mapping and adaptive subdivision of the light source based on the visibility difference between adjacent light source samples.", "authors_et_al": false, "substitute": null, "main_image": { "description": "", "filetitle": "startscreen", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 773, "image_height": 599, "name": "Knecht_Schwaerzler_2008_ash-startscreen.jpg", "type": "image/jpeg", "size": 101993, "path": "Publication:Knecht_Schwaerzler_2008_ash", "url": "https://www.cg.tuwien.ac.at/research/publications/2007/Knecht_Schwaerzler_2008_ash/Knecht_Schwaerzler_2008_ash-startscreen.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2007/Knecht_Schwaerzler_2008_ash/Knecht_Schwaerzler_2008_ash-startscreen:thumb{{size}}.png" }, "sync_repositum_override": null, "repositum_presentation_id": null, "authors": [ 678, 736 ], "matrikelnr": "0325222 / 0326294", "note": "1", "supervisor": [ 326 ], "research_areas": [], "keywords": [ "Shadow Mapping", "Real Time Rendering", "Soft Shadows" ], "weblinks": [], "files": [ { "description": "", "filetitle": "manual + executable", "main_file": false, "use_in_gallery": false, "access": "public", "preview_image_width": 773, "preview_image_height": 599, "name": "Knecht_Schwaerzler_2008_ash-manual + executable.zip", "type": "application/x-zip", "size": 8826786, "path": "Publication:Knecht_Schwaerzler_2008_ash", "preview_name": "Knecht_Schwaerzler_2008_ash-manual + executable:preview.png", "preview_type": "image/jpeg", "preview_size": 101993, "url": "https://www.cg.tuwien.ac.at/research/publications/2007/Knecht_Schwaerzler_2008_ash/Knecht_Schwaerzler_2008_ash-manual + executable.zip", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2007/Knecht_Schwaerzler_2008_ash/Knecht_Schwaerzler_2008_ash-manual + executable:thumb{{size}}.png" }, { "description": "", "filetitle": "source code", "main_file": false, "use_in_gallery": false, "access": "public", "name": "Knecht_Schwaerzler_2008_ash-source code.zip", "type": "application/x-zip", "size": 9973500, "path": "Publication:Knecht_Schwaerzler_2008_ash", "url": "https://www.cg.tuwien.ac.at/research/publications/2007/Knecht_Schwaerzler_2008_ash/Knecht_Schwaerzler_2008_ash-source code.zip", "thumb_image_sizes": [] }, { "description": "", "filetitle": "startscreen", "main_file": false, "use_in_gallery": true, "access": "public", "image_width": 773, "image_height": 599, "name": "Knecht_Schwaerzler_2008_ash-startscreen.jpg", "type": "image/jpeg", "size": 101993, "path": "Publication:Knecht_Schwaerzler_2008_ash", "url": "https://www.cg.tuwien.ac.at/research/publications/2007/Knecht_Schwaerzler_2008_ash/Knecht_Schwaerzler_2008_ash-startscreen.jpg", "thumb_image_sizes": [ 16, 64, 100, 175, 300, 600 ], "thumb_url": "https://www.cg.tuwien.ac.at/research/publications/2007/Knecht_Schwaerzler_2008_ash/Knecht_Schwaerzler_2008_ash-startscreen:thumb{{size}}.png" } ], "projects_workgroups": [ "rend" ], "url": "https://www.cg.tuwien.ac.at/research/publications/2007/Knecht_Schwaerzler_2008_ash/", "__class": "Publication" } ]