Erick Mendez

Handheld Augmented Reality for underground infrastructure visualization

In this paper, we present an Augmented Reality (AR) system for aiding field workers of utility companies in outdoor tasks such as maintenance, planning or surveying of underground infrastructure. Our work addresses these issues using spatial interaction and visualization techniques for mobile AR applications and as well as for a new mobile device design. We also present results from evaluations of the prototype application for underground infrastructure spanning various user groups. Our application has been driven by feedback from industrial collaborators in the utility sector, and includes a translation tool for automatically importing data from utility company databases of underground assets.

Interactive Focus and Context Visualization for Augmented Reality

In this article we present interactive focus and context (F+C) visualizations for augmented reality (AR) applications. We demonstrate how F+C visualizations are used to affect the users perception of hidden objects by presenting contextual information in the area of augmentation. We carefully overlay synthetic data on top of the real world imagery by taking into account the information that is about to be occluded. Furthermore, we present operations to control the amount of augmented information. Additionally, we developed an interaction tool, based on the magic lens technique, which allows for interactive separation of focus from context. We integrated our work into a rendering framework developed on top of the Studierstube augmented reality system. We finally show examples to demonstrate how our work benefits AR.

Comprehensible Visualization for Augmented Reality

This article presents interactive visualizations to support the comprehension of spatial relationships between virtual and real world objects for augmented reality (AR) applications. To enhance the clarity of such relationships we discuss visualization techniques and their suitability for AR. We apply them on different AR applications with different goals, e.g. in X-Ray vision or in applications which draw a users attention to an object of interest. We demonstrate how Focus and Context (F+C) visualizations are used to affect the users perception of hidden or nearby objects by presenting contextual information in the area of augmentation. We discuss the organization and the possible sources of data for visualizations in augmented reality and present cascaded and multi level F+C visualizations to address complex, cluttered scenes that are inevitable in real environments. This article also shows filters and tools to interactively control the amount of augmentation. It compares the impact of real world context preserving to a pure virtual and uniform enhancement of these structures for augmentations of real world imagery. Finally this paper discusses the stylization of sparse object representations for AR to improve x-ray vision.

Directing attention and influencing memory with visual saliency modulation

In augmented reality, it is often necessary to draw the users attention to particular objects in the real world without distracting her from her task. We explore the effectiveness of directing a users attention by imperceptibly modifying existing features of a video. We present three user studies of the effects of applying a saliency modulation technique to video; evaluating modulation awareness, attention, and memory. Our results validate the saliency modulation technique as an alternative means to convey information to the user, suggesting attention shifts and influencing recall of selected regions without perceptible changes to visual input.

Image-based ghostings for single layer occlusions in augmented reality

In augmented reality displays, X-Ray visualization techniques make hidden objects visible through combining the physical view with an artificial rendering of the hidden information. An important step in X-Ray visualization is to decide which parts of the physical scene should be kept and which should be replaced by overlays. The combination should provide users with essential perceptual cues to understand the relationship of depth between hidden information and the physical scene. In this paper we present an approach that addresses this decision in unknown environments by analyzing camera images of the physical scene and using the extracted information for occlusion management. Pixels are grouped into perceptually coherent image regions and a set of parameters is determined for each region. The parameters change the X-Ray visualization for either preserving existing structures or generating synthetic structures. Finally, users can customize the overall opacity of foreground regions to adapt the visualization.

Virtual redlining for civil engineering in real environments

Field workers of utility companies are regularly engaged in outdoor tasks such as network planning and inspection of underground infrastructure. Redlining is the term used for manually annotating either printed paper maps or a 2D geographic information system on a notebook computer taken to the field. Either of these approaches requires finding the physical location to be annotated on the physical or digital map. In this paper, we describe a mobile Augmented Reality (AR) system capable of supporting virtual redlining. The AR visualization delivered by the system is constructed from data directly extracted from a GIS used in day-to-day production by utility companies. We also report on encouraging trials and interviews performed with professional field workers from the utility sector.

Interactive context-driven visualization tools for augmented reality

In this article we present an interaction tool, based on the Magic Lenses technique, that allows a 3D scene to be affected dynamically given contextual information, for example, to support information filtering. We show how elements of a scene graph are grouped by context in addition to hierarchically, and, how this enables us to locally modify their rendering styles. This research has two major contributions, the use of context sensitivity with 3D Magic Lenses in a scene graph and the implementation of multiple volumetric 3D Magic Lenses for Augmented Reality setups. We have developed our tool for the Studierstube framework which allows us doing rapid prototyping of Virtual and Augmented Reality applications. Some application directions are shown throughout the paper. We compare our work with other methods, highlight strengths and weaknesses and finally discuss research directions for our work.

Focus and context in mixed reality by modulating first order salient features

We present a technique for dynamically directing a viewers attention to a focus object by analyzing and modulating bottom-up salient features of a video feed. Rather than applying a static modulation strategy, we inspect the original images saliency map, and modify the image automatically to favor the focus object. Image fragments are adaptively darkened, lightened and manipulated in hue according to local contrast information rather than global parameters. The goal is to suggest rather than force the attention of the user towards a specific location. The techniques goal is to apply only minimal changes to an image, while achieving a desired difference of saliency between focus and context regions of the image. Our technique exhibits temporal and spatial coherence and runs at interactive frame rates using GPU shaders. We present several application examples from the field of Mixed Reality, or more precisely Mediated Reality.

Adaptive Augmented Reality Using Context Markup and Style Maps

Augmented reality (AR) enables users to visualize synthetic information overlaid on top of real imagery. Such visualization may be achieved by tools that distort, filter or enhance the explored information. However, little to no work has focused on the separation of style definitions and their mapping to scene objects. We target this separation based on a context rich scenegraph. Our research allows the definition of visualization styles independent on the data to be visualized.