Motivated by existing models used for soft body simulation which are rather complex to implement,... more Motivated by existing models used for soft body simulation which are rather complex to implement, we present a novel technique which is based on simple laws of physics and gives high quality results in real-time. We base the implementation on simple thermodynamics laws and use the Clausius-Clapeyron state equation for pressure calculation. In addition, this provides us with a pressure force that is accumulated into a force accumulator of a 3D mesh object by using an existing spring-mass engine. Finally after integration of Newtons second law we obtain the behavior of a soft body with fixed or non-fixed air pressure inside of it.
Special Effects and Rendering : Proceedings from SIGRAD 2002, Linkopings universitet, Norrkoping,... more Special Effects and Rendering : Proceedings from SIGRAD 2002, Linkopings universitet, Norrkoping, Sweden, November 28th and 29th, 2002
Work in dynamic image based rendering has been presented by Kanade et al. [4] and Matusik et al. ... more Work in dynamic image based rendering has been presented by Kanade et al. [4] and Matusik et al. [5] previously. We present an alternative implementation that allows us to have a very inexpensive process of creating dynamic image-based renderings of digitally recorded photo realistic, real-life objects. Together with computer vision algorithms, the image-based objects are visualized using the Relief Texture Mapping algorithm presented by Oliveira et al [6]. As the relief engine requires depth information for all Texels representing the recorded object in an arbitrary view, a recording solution making depth extraction possible is required. Our eyes use binocular vision to produce disparities in depth, which also is the most effortless technique of producing stereovision. By using two digital video cameras, the dynamic object is recorded in stereo in different views to cover its whole volume. As the depth information from all views are generated, the different views from the image-based object are textured on a pre-defined bounding box and relief textured into a three dimensional representation by applying the known depth disparities.
When simulating physics, or other highly dynamic and complex phenom- ena, ¯nding and correcting b... more When simulating physics, or other highly dynamic and complex phenom- ena, ¯nding and correcting bugs may be very complicated and tedious using common textual debugging tools. This is because of the fact that a certain state of the simulation seldom is expressible in text and numbers so that it can be fully comprehended, let alone dynamic changes in the simulation state.This thesis proposes a way of capturing dynamic data from a simula- tion and displaying it in an appropriate view for both graphical and textual exploration. The proposed method aims at being generic enough for trans- ferring any kind of simulation data, although the main driving force is to be able to display information from dynamics simulations.
Hidden units in multi-layer networks form a representation space in which each region can be iden... more Hidden units in multi-layer networks form a representation space in which each region can be identified with a class of equivalent outputs (Elman, 1989) or a logical state in a finite state machine (Cleeremans, Servan-Schreiber & McClelland, 1989; Giles, Sun, Chen, Lee, & Chen, 1990). We extend the analysis of the spatial structure of hidden unit space to a combinatorial task, based on binding features together in a visual scene. The logical structure requires a combinatorial number of states to represent all valid scenes. On analysing our networks, we find that the high dimensionality of hidden unit space is exploited by using the intersection of neighboring regions to represent conjunctions of features. These results show how combinatorial structure can be based on the spatial nature of networks, and not just on their emulation of logical structure.
Come and listen to the story of how Battlefield 1942 was made. Starting with the first steps of c... more Come and listen to the story of how Battlefield 1942 was made. Starting with the first steps of coming up with a game-concept and persuading a publisher to sign a deal. Moving on to the huge efforts, complex process and the hurdles that needed to be overcome in production, and ending with the final stages of Alpha and Beta-testing. Speaker Bio Johan Persson has a masters-degree in "Computer science and engineering" from KTH. He was one of the co-founders of Refraction Games, the studio behind "Codename Eagle". Today this studio is Digital Illusions' Stockholm office. He had the original concept and was the lead-programmer and physics-programmer for "Battlefield 1942", a game that has so far sold well beyond a million copies worldwide. Johan Persson is currently creative director at Digital Illusions.
Work in dynamic image based rendering has been presented by Kanade et al. [4] and Matusik et al. ... more Work in dynamic image based rendering has been presented by Kanade et al. [4] and Matusik et al. [5] previously. We present an alternative implementation that allows us to have a very inexpensive process of creating dynamic image-based renderings of digitally recorded photo realistic, real-life objects. Together with computer vision algorithms, the image-based objects are visualized using the Relief Texture Mapping algorithm presented by Oliveira et al [6]. As the relief engine requires depth information for all Texels representing the recorded object in an arbitrary view, a recording solution making depth extraction possible is required. Our eyes use binocular vision to produce disparities in depth, which also is the most effortless technique of producing stereovision. By using two digital video cameras, the dynamic object is recorded in stereo in different views to cover its whole volume. As the depth information from all views are generated, the different views from the image-bas...
We present a novel system capable of capturing high dynamic range (HDR) Light Probes at video spe... more We present a novel system capable of capturing high dynamic range (HDR) Light Probes at video speed. Each Light Probe frame is built from an individual full set of exposures, all of which are captured within the frame time. The exposures are processed and assembled into a mantissa-exponent representation image within the camera unit before output, and then streamed to a standard PC. As an example, the system is capable of capturing Light Probe Images with a resolution of 512x512 pixels using a set of 10 exposures covering 15 f-stops at a frame rate of up to 25 final HDR frames per second. The system is built around commercial special-purpose camera hardware with on-chip programmable image processing logic and tightly integrated frame buffer memory, and the algorithm is implemented as custom downloadable microcode software.
Fourth IEEE and ACM International Symposium on Mixed and Augmented Reality (ISMAR'05), 2005
Mobile phones are an ideal platform for augmented reality. In this paper we describe how they can... more Mobile phones are an ideal platform for augmented reality. In this paper we describe how they can also be used to support face to face collaborative AR gaming. We have created a custom port of the ARToolKit library to the Symbian mobile phone operating system and then developed a sample collaborative AR game based on this. We describe the game in detail and user feedback from people who have played the game. We also provide general design guidelines that could be useful for others who are developing mobile phone collaborative AR applications.
ACM SIGGRAPH 2002 conference abstracts and applications, 2002
Hybrid representations - that of using image and procedural methods to synthesize images. Procedu... more Hybrid representations - that of using image and procedural methods to synthesize images. Procedural methods allow us to describe media (2D images, 3D objects etc.) with very little information and render it photorealistically. Since the procedure is run on the client (for instance a PC or a mobile phone with limited network), it makes sense to adapt the procedure to the properties of the client.
Proceedings of the 4th international conference on Mobile and ubiquitous multimedia - MUM '05, 2005
In this paper we describe a mobile phone based Augmented Reality application for 3D scene assembl... more In this paper we describe a mobile phone based Augmented Reality application for 3D scene assembly. Augmented Reality on mobile phones extends the interaction capabilities on such handheld devices. It adds a 6 DOF isomorphic interaction technique for manipulating 3D content. We give details of an application that we believe to be the first where 3D content can be manipulated using both the movement of a camera tracked mobile phone and a traditional button interface as input for transformations. By centering the scene in a tangible marker space in front of the phone we provide a mean for bimanual interaction. We describe the implementation, the interaction techniques we have developed and initial user response to trying the application.
Smartphones with built-in cameras are becoming ubiquitous. These devices couple a camera with com... more Smartphones with built-in cameras are becoming ubiquitous. These devices couple a camera with communication and processing units and are increasingly capable of 3D rendering. We have conducted camera sensitivity tests on current smartphones to evaluate in what extent they can be used for Augmented Reality (AR) using optical tracking.
ACM SIGGRAPH 2002 conference abstracts and applications, 2002
This sketch presents a prototype developed as part of the Backseat gaming project. The aim of the... more This sketch presents a prototype developed as part of the Backseat gaming project. The aim of the project is to explore how to make use of mobile properties for developing compelling and fun game experiences. The prototype is developed for use in a highly mobile situation, that of a car passenger and is realized by the use of mobile devices and the users physical location during speed to merge the virtual content and surrounding road context into an augmented reality game. In this research, in addition to location, we also introduce variables such as speed, direction, timing, changing surrounding, fast movement of manipulative objects and multiple entry and exits.
An important way for describing groups is by finite presentations. Large presentations arise in p... more An important way for describing groups is by finite presentations. Large presentations arise in practice which are poorly suited for either human or computer use. Presentation simplification processes which take "bad" presentations and produce "good" presentations have been developed. Substantial use is made of substring searching and appropriate techniques for this context are described. Effective use is made of signatures and change flags. Change flags are shown to be the most beneficial of the methods tested here, with very significant performance improvement. Experimental performance figures are given.
An important way for describing groups is by flnite presentations. Large presentations arise in p... more An important way for describing groups is by flnite presentations. Large presentations arise in practice which are poorly suited for either human or computer use. Presentation simpliflcation processes which take \bad" presentations and produce \good" presentations have been developed. Substantial use is made of substring searching and appropriate techniques for this context are described. Efiective use is made of signatures and change ∞ags. Change ∞ags are shown to be the most beneflcial of the methods tested here, with very signiflcant performance improvement. Experimental performance flgures are given.
Mobile phones have reached a level where it is possible to run selfcontained Augmented Reality ap... more Mobile phones have reached a level where it is possible to run selfcontained Augmented Reality applications using the built-in camera for optical tracking. In this paper we present some of our work in this area. We have created a custom port of the ARToolKit library to the Symbian mobile phone operating system and then developed sample applications which have been evaluated. These include a face-to-face collaborative AR game where we conducted a user study to evaluate multi-modal feedback. We also examined user interface issues where an AR enabled mobile phone acts as an interaction device. Additionally, we discuss how traditional 3D manipulation techniques apply to this new platform. We also describe a mobile phone based Augmented Reality application for 3D scene assembly, which adds a 6 DOF isomorphic interaction technique for manipulating 3D content.
Motivated by existing models used for soft body simulation which are rather complex to implement,... more Motivated by existing models used for soft body simulation which are rather complex to implement, we present a novel technique which is based on simple laws of physics and gives high quality results in real-time. We base the implementation on simple thermodynamics laws and use the Clausius-Clapeyron state equation for pressure calculation. In addition, this provides us with a pressure force that is accumulated into a force accumulator of a 3D mesh object by using an existing spring-mass engine. Finally after integration of Newtons second law we obtain the behavior of a soft body with fixed or non-fixed air pressure inside of it.
Special Effects and Rendering : Proceedings from SIGRAD 2002, Linkopings universitet, Norrkoping,... more Special Effects and Rendering : Proceedings from SIGRAD 2002, Linkopings universitet, Norrkoping, Sweden, November 28th and 29th, 2002
Work in dynamic image based rendering has been presented by Kanade et al. [4] and Matusik et al. ... more Work in dynamic image based rendering has been presented by Kanade et al. [4] and Matusik et al. [5] previously. We present an alternative implementation that allows us to have a very inexpensive process of creating dynamic image-based renderings of digitally recorded photo realistic, real-life objects. Together with computer vision algorithms, the image-based objects are visualized using the Relief Texture Mapping algorithm presented by Oliveira et al [6]. As the relief engine requires depth information for all Texels representing the recorded object in an arbitrary view, a recording solution making depth extraction possible is required. Our eyes use binocular vision to produce disparities in depth, which also is the most effortless technique of producing stereovision. By using two digital video cameras, the dynamic object is recorded in stereo in different views to cover its whole volume. As the depth information from all views are generated, the different views from the image-based object are textured on a pre-defined bounding box and relief textured into a three dimensional representation by applying the known depth disparities.
When simulating physics, or other highly dynamic and complex phenom- ena, ¯nding and correcting b... more When simulating physics, or other highly dynamic and complex phenom- ena, ¯nding and correcting bugs may be very complicated and tedious using common textual debugging tools. This is because of the fact that a certain state of the simulation seldom is expressible in text and numbers so that it can be fully comprehended, let alone dynamic changes in the simulation state.This thesis proposes a way of capturing dynamic data from a simula- tion and displaying it in an appropriate view for both graphical and textual exploration. The proposed method aims at being generic enough for trans- ferring any kind of simulation data, although the main driving force is to be able to display information from dynamics simulations.
Hidden units in multi-layer networks form a representation space in which each region can be iden... more Hidden units in multi-layer networks form a representation space in which each region can be identified with a class of equivalent outputs (Elman, 1989) or a logical state in a finite state machine (Cleeremans, Servan-Schreiber & McClelland, 1989; Giles, Sun, Chen, Lee, & Chen, 1990). We extend the analysis of the spatial structure of hidden unit space to a combinatorial task, based on binding features together in a visual scene. The logical structure requires a combinatorial number of states to represent all valid scenes. On analysing our networks, we find that the high dimensionality of hidden unit space is exploited by using the intersection of neighboring regions to represent conjunctions of features. These results show how combinatorial structure can be based on the spatial nature of networks, and not just on their emulation of logical structure.
Come and listen to the story of how Battlefield 1942 was made. Starting with the first steps of c... more Come and listen to the story of how Battlefield 1942 was made. Starting with the first steps of coming up with a game-concept and persuading a publisher to sign a deal. Moving on to the huge efforts, complex process and the hurdles that needed to be overcome in production, and ending with the final stages of Alpha and Beta-testing. Speaker Bio Johan Persson has a masters-degree in "Computer science and engineering" from KTH. He was one of the co-founders of Refraction Games, the studio behind "Codename Eagle". Today this studio is Digital Illusions' Stockholm office. He had the original concept and was the lead-programmer and physics-programmer for "Battlefield 1942", a game that has so far sold well beyond a million copies worldwide. Johan Persson is currently creative director at Digital Illusions.
Work in dynamic image based rendering has been presented by Kanade et al. [4] and Matusik et al. ... more Work in dynamic image based rendering has been presented by Kanade et al. [4] and Matusik et al. [5] previously. We present an alternative implementation that allows us to have a very inexpensive process of creating dynamic image-based renderings of digitally recorded photo realistic, real-life objects. Together with computer vision algorithms, the image-based objects are visualized using the Relief Texture Mapping algorithm presented by Oliveira et al [6]. As the relief engine requires depth information for all Texels representing the recorded object in an arbitrary view, a recording solution making depth extraction possible is required. Our eyes use binocular vision to produce disparities in depth, which also is the most effortless technique of producing stereovision. By using two digital video cameras, the dynamic object is recorded in stereo in different views to cover its whole volume. As the depth information from all views are generated, the different views from the image-bas...
We present a novel system capable of capturing high dynamic range (HDR) Light Probes at video spe... more We present a novel system capable of capturing high dynamic range (HDR) Light Probes at video speed. Each Light Probe frame is built from an individual full set of exposures, all of which are captured within the frame time. The exposures are processed and assembled into a mantissa-exponent representation image within the camera unit before output, and then streamed to a standard PC. As an example, the system is capable of capturing Light Probe Images with a resolution of 512x512 pixels using a set of 10 exposures covering 15 f-stops at a frame rate of up to 25 final HDR frames per second. The system is built around commercial special-purpose camera hardware with on-chip programmable image processing logic and tightly integrated frame buffer memory, and the algorithm is implemented as custom downloadable microcode software.
Fourth IEEE and ACM International Symposium on Mixed and Augmented Reality (ISMAR'05), 2005
Mobile phones are an ideal platform for augmented reality. In this paper we describe how they can... more Mobile phones are an ideal platform for augmented reality. In this paper we describe how they can also be used to support face to face collaborative AR gaming. We have created a custom port of the ARToolKit library to the Symbian mobile phone operating system and then developed a sample collaborative AR game based on this. We describe the game in detail and user feedback from people who have played the game. We also provide general design guidelines that could be useful for others who are developing mobile phone collaborative AR applications.
ACM SIGGRAPH 2002 conference abstracts and applications, 2002
Hybrid representations - that of using image and procedural methods to synthesize images. Procedu... more Hybrid representations - that of using image and procedural methods to synthesize images. Procedural methods allow us to describe media (2D images, 3D objects etc.) with very little information and render it photorealistically. Since the procedure is run on the client (for instance a PC or a mobile phone with limited network), it makes sense to adapt the procedure to the properties of the client.
Proceedings of the 4th international conference on Mobile and ubiquitous multimedia - MUM '05, 2005
In this paper we describe a mobile phone based Augmented Reality application for 3D scene assembl... more In this paper we describe a mobile phone based Augmented Reality application for 3D scene assembly. Augmented Reality on mobile phones extends the interaction capabilities on such handheld devices. It adds a 6 DOF isomorphic interaction technique for manipulating 3D content. We give details of an application that we believe to be the first where 3D content can be manipulated using both the movement of a camera tracked mobile phone and a traditional button interface as input for transformations. By centering the scene in a tangible marker space in front of the phone we provide a mean for bimanual interaction. We describe the implementation, the interaction techniques we have developed and initial user response to trying the application.
Smartphones with built-in cameras are becoming ubiquitous. These devices couple a camera with com... more Smartphones with built-in cameras are becoming ubiquitous. These devices couple a camera with communication and processing units and are increasingly capable of 3D rendering. We have conducted camera sensitivity tests on current smartphones to evaluate in what extent they can be used for Augmented Reality (AR) using optical tracking.
ACM SIGGRAPH 2002 conference abstracts and applications, 2002
This sketch presents a prototype developed as part of the Backseat gaming project. The aim of the... more This sketch presents a prototype developed as part of the Backseat gaming project. The aim of the project is to explore how to make use of mobile properties for developing compelling and fun game experiences. The prototype is developed for use in a highly mobile situation, that of a car passenger and is realized by the use of mobile devices and the users physical location during speed to merge the virtual content and surrounding road context into an augmented reality game. In this research, in addition to location, we also introduce variables such as speed, direction, timing, changing surrounding, fast movement of manipulative objects and multiple entry and exits.
An important way for describing groups is by finite presentations. Large presentations arise in p... more An important way for describing groups is by finite presentations. Large presentations arise in practice which are poorly suited for either human or computer use. Presentation simplification processes which take "bad" presentations and produce "good" presentations have been developed. Substantial use is made of substring searching and appropriate techniques for this context are described. Effective use is made of signatures and change flags. Change flags are shown to be the most beneficial of the methods tested here, with very significant performance improvement. Experimental performance figures are given.
An important way for describing groups is by flnite presentations. Large presentations arise in p... more An important way for describing groups is by flnite presentations. Large presentations arise in practice which are poorly suited for either human or computer use. Presentation simpliflcation processes which take \bad" presentations and produce \good" presentations have been developed. Substantial use is made of substring searching and appropriate techniques for this context are described. Efiective use is made of signatures and change ∞ags. Change ∞ags are shown to be the most beneflcial of the methods tested here, with very signiflcant performance improvement. Experimental performance flgures are given.
Mobile phones have reached a level where it is possible to run selfcontained Augmented Reality ap... more Mobile phones have reached a level where it is possible to run selfcontained Augmented Reality applications using the built-in camera for optical tracking. In this paper we present some of our work in this area. We have created a custom port of the ARToolKit library to the Symbian mobile phone operating system and then developed sample applications which have been evaluated. These include a face-to-face collaborative AR game where we conducted a user study to evaluate multi-modal feedback. We also examined user interface issues where an AR enabled mobile phone acts as an interaction device. Additionally, we discuss how traditional 3D manipulation techniques apply to this new platform. We also describe a mobile phone based Augmented Reality application for 3D scene assembly, which adds a 6 DOF isomorphic interaction technique for manipulating 3D content.
Uploads
Papers by Mark Ollila