The McGurk effect test is a method to evaluate articulation of talking heads. Our work addresses ... more The McGurk effect test is a method to evaluate articulation of talking heads. Our work addresses the issue of corrected vision influence on the McGurk effect perception. We conducted an experiment to investigate this influence. Measured data shows different perception of participants with corrected vision in some cases. The results could help talking head evaluators to compare talking head implementations each other with elimination of the influence of corrected vision.
International Conference on Human-Computer Interaction, 2003
In this paper we report on some problems arising during the building of an educational system in ... more In this paper we report on some problems arising during the building of an educational system in the area of human computer interaction in the Czech Republic. An overview of teaching and educational activities, courses and study programs related to the HCI field being offered by the most significant Czech universities as well as the overview of public and common activities in the HCI developments are presented.
The increasing power and display resolution of mobile devices allow the user nowadays to work wit... more The increasing power and display resolution of mobile devices allow the user nowadays to work with 3D information in mobile environment. The use of this new technology brings some new problems that need an urgent solution. One of them has its roots in the fact that common users are not trained to work in 3D graphical environment in general. The main obstacle for a common user is the fact that 3D environment offers too much freedom for object manipulation in comparison with situation in 2D environment. There are various solutions to this problem but usually they do not handle efficiently the problem of navigation in 3D environment in context of handling appropriate information density on a small screen on a mobile device. Our approach is based on transformation of a 3D scene in 2D representation in order to decrease freedom of movement during navigation in the scene. The navigation (and other types of interaction) is performed in 2D environment - the information acquired during inter...
From 01.05.05 to 04.05.05, the Dagstuhl Seminar 05181 ``Mobile Computing and Ambient Intelligence... more From 01.05.05 to 04.05.05, the Dagstuhl Seminar 05181 ``Mobile Computing and Ambient Intelligence: The Challenge of Multimedia''was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available.
This chapter presents a design process for developing a conversational navigation agent for visua... more This chapter presents a design process for developing a conversational navigation agent for visually impaired pedestrians where communication runs in natural language. This approach brings a lot of new problems with opportunity to solve them in nontraditional ways. The conversation with the agent is an example of a problem-solving process with several complex parts of the solution needed to be executed by the user. The user can ask additional questions about each part of the solution, thus adaptively changing the level of detail of information acquired, or to alternate the whole process to fit user preferences. In this way, the agent can replace a human navigator. Using this design process exemplar, we provide guidance on creating similar conversational agents, which utilize a natural language user interface. The guidance is supported by the results of several experiments conducted with participants with visual impairments.
Proceedings of the 2003 International Conference on Machine Learning and Cybernetics (IEEE Cat. No.03EX693)
The main characteristics of technological processes is their dynamic behavior. As the data from m... more The main characteristics of technological processes is their dynamic behavior. As the data from most general applications can be visualized by means of static images the appropriate methods for visualization of technological processes should be developed. Some applications (will be discussed later) attempt to visualize dynamic processes, but the known approaches usually suffer from some disadvantages. Moreover most of the commercial solutions available do not cover problems for specific applications. Our attempt was to investigate problems of dynamic visualization for specific applications. This allowed us to develop and implement a specific approach where acceleration both of simulation and visualization processes could be used (which gave us an advantage over commercial solutions based on AVS and other systems).
Terrains are visually important and commonly used in computer graphics. While many algorithms for... more Terrains are visually important and commonly used in computer graphics. While many algorithms for their generation exist, it is difficult to assess the realism of a generated terrain. This paper presents a first step in the direction of perceptual evaluation of terrain models. We gathered and categorized several classes of real terrains and we generated synthetic terrains by using methods from computer graphics. We then conducted two large studies ranking the terrains perceptually and showing that the synthetic terrains are perceived as lacking realism as compared to the real ones. Then we provide insight into the features that affect the perceived realism by a quantitative evaluation based on localized geomorphology-based landform features (geomorphons) that categorize terrain structures such as valleys, ridges, hollows, etc. We show that the presence or absence of certain features have a significant perceptual effect. We then introduce Perceived Terrain Realism Metrics (PTRM); a p...
As the popularity of Smart Televisions (TVs) and interactive Smart TV applications (apps) has rec... more As the popularity of Smart Televisions (TVs) and interactive Smart TV applications (apps) has recently grown, the usability of these apps has become an important quality characteristic. Previous studies examined Smart TV apps from a usability perspective. However, these methods are mainly manual, and the potential of automated model-based testing methods for usability testing purposes has not yet been fully explored. In this paper, we propose an approach to test the usability of Smart TV apps based on the automated generation of a Smart TV user interaction model from an existing app by a specialized automated crawler. By means of this model, defined user tasks in the Smart TV app can be evaluated automatically in terms of their feasibility and estimated user effort, which reflects the usability of the analyzed app. This analysis can be applied in the context of regular users and users with various specific needs. The findings from this model-based automated analysis approach can be used to optimize the user interface of a Smart TV app to increase its usability, accessibility, and quality.
This paper presents the latest advances and research in Computer Graphics education in a nutshell... more This paper presents the latest advances and research in Computer Graphics education in a nutshell. It is concerned with topics that were presented at the Education Track of the Eurographics Conference held in Lisbon in 2016. We describe works corresponding to approaches to Computer Graphics education that are unconventional in some way and attempt to tackle unsolved problems and challenges regarding the role of arts in computer graphics education, the role of research‐oriented activities in undergraduate education and the interaction among different areas of Computer Graphics, as well as their application to courses or extra‐curricular activities. We present related works addressing these topics and report experiences, successes and issues in implementing the approaches.
In this paper we report on some problems arising during the building of an educational system in ... more In this paper we report on some problems arising during the building of an educational system in the area of human computer interaction in the Czech Republic. An overview of teaching and educational activities, courses and study programs related to the HCI field being offered by the most significant Czech universities as well as the overview of public and common activities in the HCI developments are presented.
Four years ago I wrote an article about the state of the art in the field of computer graphics ed... more Four years ago I wrote an article about the state of the art in the field of computer graphics education in the former Czechoslovakia. This article was published in Computer Graphics January 1992. Perhaps the most important statement in this article was the fact that computer graphics has a long tradition in this country. In the final section of this article some future plans and goals that we wanted to achieve were stated. Four years is a period of time long enough to evaluate the results achieved. The following text is information about recent developments in the Czech Republic in the field of computer graphics.
Communications in Computer and Information Science, 2011
The McGurk effect test is a method to evaluate articulation of talking heads. Our work addresses ... more The McGurk effect test is a method to evaluate articulation of talking heads. Our work addresses the issue of corrected vision influence on the McGurk effect perception. We conducted an experiment to investigate this influence. Measured data shows different perception of participants with corrected vision in some cases. The results could help talking head evaluators to compare talking head implementations each other with elimination of the influence of corrected vision.
International Conference in Central Europe on Computer Graphics and Visualization, 2004
We describe a method allowing users to walk through 3D scenes using Macromedia Flash player. The ... more We describe a method allowing users to walk through 3D scenes using Macromedia Flash player. The method is optimised for low data transfer rates and low demands on the displaying device, which makes it suited especially for mobile devices. The walkthroughs are partially pre-computed on a server and partially calculated directly on the PDA. Non-photorealistic rendering is used for more eye-pleasing results and for achieving higher data compression.
Proceedings of the 20th Spring Conference on Computer Graphics, 2004
In many applications complex structured data have been used. Visualization of these data structur... more In many applications complex structured data have been used. Visualization of these data structures allows a user to get better insight both in the data structure and in the application itself. We present a visualization technique of structured data-oriented XML formats. Customizable visualization is done by means of tree rewriting. This allows for an efficient filtration and transformation of the document tree to fit particular user needs as well as a transformation to a structure with a predefined graphical interpretation. A graphical representation of the tree rewriting rules for an interactive manipulation is presented, so the system itself can be considered a graphical language. The graphical representation is based on tree maps.
There are many situations in which listening to a text produced by a textto-speech system is easi... more There are many situations in which listening to a text produced by a textto-speech system is easier or safer than reading, for example when driving a car. Technical documents, such as conference articles, manuals etc., usually are comprised of relatively plain and unequivocal sentences. These documents usually contain words and terms unknown to the listener because they are full of domain specific terminology. In this paper, we propose a system that allows the users to interrupt the reading upon hearing an unknown or confusing term by a non-speech acoustic gesture (e.g. "uhm?"). Upon this interruption, the system provides a definition of the term, retrieved from Wikipedia, the Free Encyclopedia. The selection of the non-speech gestures has been made with a respect to the cross-cultural applicability and language independence. In this paper we present a set of novel tools enabling this kind of interaction.
Proceedings. Eighth International Conference on Information Visualisation, 2004. IV 2004.
Nowadays, it is evident that we must consider human perceptual properties to visualize informatio... more Nowadays, it is evident that we must consider human perceptual properties to visualize information clearly and efficiently. We may utilize computational models of human visual systems to consider human perception well. Image quality assessment is a challenging task that is traditionally approached by such computational models. Recently, a new assessment methodology based on structural similarity has been proposed. In this paper we select two representative models of each group, the Visible Differences Predictor and the Structural SIMilarity index, for evaluation. We begin with the description of these two approaches and models. We then depict the subjective tests that we have conducted to obtain mean opinion scores. Inputs to these tests included uniformly compressed images and images compressed non-uniformly with regions of interest. Then, we discuss the performance of the two models, and the similarities and differences between the two models. We end with a summary of the important advantages of each approach.
2009 15th International Conference on Virtual Systems and Multimedia, 2009
Cultural heritage presentation is a topic we at CTU Prague deal with for more than ten years. In ... more Cultural heritage presentation is a topic we at CTU Prague deal with for more than ten years. In this paper we present our experience with user interface design where serious games paradigm has been utilized. The survey of selected projects represents various technologies and approaches for cultural heritage data handling that includes data acquisition, presentation, interaction and educational issues. The aim of our activities was to develop a systematic approach to the user interface design for the given class of applications.
The paper describes a new approach to the visualization of atomic collision cascades and using th... more The paper describes a new approach to the visualization of atomic collision cascades and using the interaction with visualized data. The collision cascade i s a p h ysical phenomenon initiated by b o m barding the surface of a solid with accelerated atomic particles. The process evolves in time and therefore it is necessary to develop some tools that would allow to investigate and visualize the dynamics of the process. Such tools are classi ers ( lters) that enable to select and visualize objects with speci c dynamic properties. As the visualization has been done in a 3D environment a question arises how to specify e ectively and user friendly both the properties and the objects in the 3D space. Several techniques are available that allow interaction in the 3D space. It has been necessary to test some of these techniques and to determine which one is the most suitable for the given application class.
Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, 2012
This paper describes a model of adaptation of multimedia application. The adaptation is based on ... more This paper describes a model of adaptation of multimedia application. The adaptation is based on user's progress in using a content of the application and a plan that defines long-time usage strategy of the application. The model was applied to education application but it can be used also in other use-cases. This model was designed to be easy to implement and use, and it is an alternative to robust learning models. The implementation of the model is presented on Physical Exercise application.
The McGurk effect test is a method to evaluate articulation of talking heads. Our work addresses ... more The McGurk effect test is a method to evaluate articulation of talking heads. Our work addresses the issue of corrected vision influence on the McGurk effect perception. We conducted an experiment to investigate this influence. Measured data shows different perception of participants with corrected vision in some cases. The results could help talking head evaluators to compare talking head implementations each other with elimination of the influence of corrected vision.
International Conference on Human-Computer Interaction, 2003
In this paper we report on some problems arising during the building of an educational system in ... more In this paper we report on some problems arising during the building of an educational system in the area of human computer interaction in the Czech Republic. An overview of teaching and educational activities, courses and study programs related to the HCI field being offered by the most significant Czech universities as well as the overview of public and common activities in the HCI developments are presented.
The increasing power and display resolution of mobile devices allow the user nowadays to work wit... more The increasing power and display resolution of mobile devices allow the user nowadays to work with 3D information in mobile environment. The use of this new technology brings some new problems that need an urgent solution. One of them has its roots in the fact that common users are not trained to work in 3D graphical environment in general. The main obstacle for a common user is the fact that 3D environment offers too much freedom for object manipulation in comparison with situation in 2D environment. There are various solutions to this problem but usually they do not handle efficiently the problem of navigation in 3D environment in context of handling appropriate information density on a small screen on a mobile device. Our approach is based on transformation of a 3D scene in 2D representation in order to decrease freedom of movement during navigation in the scene. The navigation (and other types of interaction) is performed in 2D environment - the information acquired during inter...
From 01.05.05 to 04.05.05, the Dagstuhl Seminar 05181 ``Mobile Computing and Ambient Intelligence... more From 01.05.05 to 04.05.05, the Dagstuhl Seminar 05181 ``Mobile Computing and Ambient Intelligence: The Challenge of Multimedia''was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available.
This chapter presents a design process for developing a conversational navigation agent for visua... more This chapter presents a design process for developing a conversational navigation agent for visually impaired pedestrians where communication runs in natural language. This approach brings a lot of new problems with opportunity to solve them in nontraditional ways. The conversation with the agent is an example of a problem-solving process with several complex parts of the solution needed to be executed by the user. The user can ask additional questions about each part of the solution, thus adaptively changing the level of detail of information acquired, or to alternate the whole process to fit user preferences. In this way, the agent can replace a human navigator. Using this design process exemplar, we provide guidance on creating similar conversational agents, which utilize a natural language user interface. The guidance is supported by the results of several experiments conducted with participants with visual impairments.
Proceedings of the 2003 International Conference on Machine Learning and Cybernetics (IEEE Cat. No.03EX693)
The main characteristics of technological processes is their dynamic behavior. As the data from m... more The main characteristics of technological processes is their dynamic behavior. As the data from most general applications can be visualized by means of static images the appropriate methods for visualization of technological processes should be developed. Some applications (will be discussed later) attempt to visualize dynamic processes, but the known approaches usually suffer from some disadvantages. Moreover most of the commercial solutions available do not cover problems for specific applications. Our attempt was to investigate problems of dynamic visualization for specific applications. This allowed us to develop and implement a specific approach where acceleration both of simulation and visualization processes could be used (which gave us an advantage over commercial solutions based on AVS and other systems).
Terrains are visually important and commonly used in computer graphics. While many algorithms for... more Terrains are visually important and commonly used in computer graphics. While many algorithms for their generation exist, it is difficult to assess the realism of a generated terrain. This paper presents a first step in the direction of perceptual evaluation of terrain models. We gathered and categorized several classes of real terrains and we generated synthetic terrains by using methods from computer graphics. We then conducted two large studies ranking the terrains perceptually and showing that the synthetic terrains are perceived as lacking realism as compared to the real ones. Then we provide insight into the features that affect the perceived realism by a quantitative evaluation based on localized geomorphology-based landform features (geomorphons) that categorize terrain structures such as valleys, ridges, hollows, etc. We show that the presence or absence of certain features have a significant perceptual effect. We then introduce Perceived Terrain Realism Metrics (PTRM); a p...
As the popularity of Smart Televisions (TVs) and interactive Smart TV applications (apps) has rec... more As the popularity of Smart Televisions (TVs) and interactive Smart TV applications (apps) has recently grown, the usability of these apps has become an important quality characteristic. Previous studies examined Smart TV apps from a usability perspective. However, these methods are mainly manual, and the potential of automated model-based testing methods for usability testing purposes has not yet been fully explored. In this paper, we propose an approach to test the usability of Smart TV apps based on the automated generation of a Smart TV user interaction model from an existing app by a specialized automated crawler. By means of this model, defined user tasks in the Smart TV app can be evaluated automatically in terms of their feasibility and estimated user effort, which reflects the usability of the analyzed app. This analysis can be applied in the context of regular users and users with various specific needs. The findings from this model-based automated analysis approach can be used to optimize the user interface of a Smart TV app to increase its usability, accessibility, and quality.
This paper presents the latest advances and research in Computer Graphics education in a nutshell... more This paper presents the latest advances and research in Computer Graphics education in a nutshell. It is concerned with topics that were presented at the Education Track of the Eurographics Conference held in Lisbon in 2016. We describe works corresponding to approaches to Computer Graphics education that are unconventional in some way and attempt to tackle unsolved problems and challenges regarding the role of arts in computer graphics education, the role of research‐oriented activities in undergraduate education and the interaction among different areas of Computer Graphics, as well as their application to courses or extra‐curricular activities. We present related works addressing these topics and report experiences, successes and issues in implementing the approaches.
In this paper we report on some problems arising during the building of an educational system in ... more In this paper we report on some problems arising during the building of an educational system in the area of human computer interaction in the Czech Republic. An overview of teaching and educational activities, courses and study programs related to the HCI field being offered by the most significant Czech universities as well as the overview of public and common activities in the HCI developments are presented.
Four years ago I wrote an article about the state of the art in the field of computer graphics ed... more Four years ago I wrote an article about the state of the art in the field of computer graphics education in the former Czechoslovakia. This article was published in Computer Graphics January 1992. Perhaps the most important statement in this article was the fact that computer graphics has a long tradition in this country. In the final section of this article some future plans and goals that we wanted to achieve were stated. Four years is a period of time long enough to evaluate the results achieved. The following text is information about recent developments in the Czech Republic in the field of computer graphics.
Communications in Computer and Information Science, 2011
The McGurk effect test is a method to evaluate articulation of talking heads. Our work addresses ... more The McGurk effect test is a method to evaluate articulation of talking heads. Our work addresses the issue of corrected vision influence on the McGurk effect perception. We conducted an experiment to investigate this influence. Measured data shows different perception of participants with corrected vision in some cases. The results could help talking head evaluators to compare talking head implementations each other with elimination of the influence of corrected vision.
International Conference in Central Europe on Computer Graphics and Visualization, 2004
We describe a method allowing users to walk through 3D scenes using Macromedia Flash player. The ... more We describe a method allowing users to walk through 3D scenes using Macromedia Flash player. The method is optimised for low data transfer rates and low demands on the displaying device, which makes it suited especially for mobile devices. The walkthroughs are partially pre-computed on a server and partially calculated directly on the PDA. Non-photorealistic rendering is used for more eye-pleasing results and for achieving higher data compression.
Proceedings of the 20th Spring Conference on Computer Graphics, 2004
In many applications complex structured data have been used. Visualization of these data structur... more In many applications complex structured data have been used. Visualization of these data structures allows a user to get better insight both in the data structure and in the application itself. We present a visualization technique of structured data-oriented XML formats. Customizable visualization is done by means of tree rewriting. This allows for an efficient filtration and transformation of the document tree to fit particular user needs as well as a transformation to a structure with a predefined graphical interpretation. A graphical representation of the tree rewriting rules for an interactive manipulation is presented, so the system itself can be considered a graphical language. The graphical representation is based on tree maps.
There are many situations in which listening to a text produced by a textto-speech system is easi... more There are many situations in which listening to a text produced by a textto-speech system is easier or safer than reading, for example when driving a car. Technical documents, such as conference articles, manuals etc., usually are comprised of relatively plain and unequivocal sentences. These documents usually contain words and terms unknown to the listener because they are full of domain specific terminology. In this paper, we propose a system that allows the users to interrupt the reading upon hearing an unknown or confusing term by a non-speech acoustic gesture (e.g. "uhm?"). Upon this interruption, the system provides a definition of the term, retrieved from Wikipedia, the Free Encyclopedia. The selection of the non-speech gestures has been made with a respect to the cross-cultural applicability and language independence. In this paper we present a set of novel tools enabling this kind of interaction.
Proceedings. Eighth International Conference on Information Visualisation, 2004. IV 2004.
Nowadays, it is evident that we must consider human perceptual properties to visualize informatio... more Nowadays, it is evident that we must consider human perceptual properties to visualize information clearly and efficiently. We may utilize computational models of human visual systems to consider human perception well. Image quality assessment is a challenging task that is traditionally approached by such computational models. Recently, a new assessment methodology based on structural similarity has been proposed. In this paper we select two representative models of each group, the Visible Differences Predictor and the Structural SIMilarity index, for evaluation. We begin with the description of these two approaches and models. We then depict the subjective tests that we have conducted to obtain mean opinion scores. Inputs to these tests included uniformly compressed images and images compressed non-uniformly with regions of interest. Then, we discuss the performance of the two models, and the similarities and differences between the two models. We end with a summary of the important advantages of each approach.
2009 15th International Conference on Virtual Systems and Multimedia, 2009
Cultural heritage presentation is a topic we at CTU Prague deal with for more than ten years. In ... more Cultural heritage presentation is a topic we at CTU Prague deal with for more than ten years. In this paper we present our experience with user interface design where serious games paradigm has been utilized. The survey of selected projects represents various technologies and approaches for cultural heritage data handling that includes data acquisition, presentation, interaction and educational issues. The aim of our activities was to develop a systematic approach to the user interface design for the given class of applications.
The paper describes a new approach to the visualization of atomic collision cascades and using th... more The paper describes a new approach to the visualization of atomic collision cascades and using the interaction with visualized data. The collision cascade i s a p h ysical phenomenon initiated by b o m barding the surface of a solid with accelerated atomic particles. The process evolves in time and therefore it is necessary to develop some tools that would allow to investigate and visualize the dynamics of the process. Such tools are classi ers ( lters) that enable to select and visualize objects with speci c dynamic properties. As the visualization has been done in a 3D environment a question arises how to specify e ectively and user friendly both the properties and the objects in the 3D space. Several techniques are available that allow interaction in the 3D space. It has been necessary to test some of these techniques and to determine which one is the most suitable for the given application class.
Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, 2012
This paper describes a model of adaptation of multimedia application. The adaptation is based on ... more This paper describes a model of adaptation of multimedia application. The adaptation is based on user's progress in using a content of the application and a plan that defines long-time usage strategy of the application. The model was applied to education application but it can be used also in other use-cases. This model was designed to be easy to implement and use, and it is an alternative to robust learning models. The implementation of the model is presented on Physical Exercise application.
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Papers by Pavel Slavík