Ville-Veikko Mattila

An Augmented Reality X-Ray system based on visual saliency

In the past, several systems have been presented that enable users to view occluded points of interest using Augmented Reality X-ray visualizations. It is challenging to design a visualization that provides correct occlusions between occluder and occluded objects while maximizing legibility. We have previously published an Augmented Reality X-ray visualization that renders edges of the occluder region over the occluded region to facilitate correct occlusions while providing foreground context. While this approach is simple and works in a wide range of situations, it provides only minimal context of the occluder object.

Semantic analysis of speech quality in mobile communications: descriptive language development and mapping to acceptability

Descriptive analysis of processed speech quality was carried out by semantic differentiation and external preference mapping was used to relate the attributes to overall quality judgements. A clean speech sample and a speech sample corrupted by car cabin noise from two speakers were processed by different processing chains representing, for example, transmissions over real GSM networks and erroneous transmission channels, various standardized speech coders, etc. resulting in a total of 170 samples. The perceptual characteristics of the test samples were described by 18 screened subjects and the final descriptive language with 21 attributes and their rating scales were developed in panel discussions. The scaled attributes were mapped to overall quality evaluations collected from 30 screened subjects by partial least squares regression (PLSR).

A Lightweight Platform for Web Mashups in Immersive Mirror Worlds

Cloud City Scene is a lightweight platform that enables visualizations of Web mashups in an immersive mirror-world environment in which annotations blend in with buildings, terrain, and objects, letting users interact with the underlying real-world scene.

Visualizing web mash-ups for in-situ vision-based mobile AR applications

Augmented reality applications are gaining popularity due to increased capabilities of modern mobile devices. Creating AR content however is tedious and traditionally done on desktop environments by professionals, with extensive knowledge and/or even programming skills required. In this demo, we demonstrate a complete mobile approach for creating vision-based AR in both indoor and outdoor environment. Using hyperlinks, Web mashups are built to dynamically augment the physical world by normal users without programing skills.

A 3D map augmented photo gallery application on mobile device

This paper proposes a 3D map augmented photo gallery mobile application that allows user to virtually transit from 2D image space to the 3D map space, to expand the field of view to surrounding environments that are not visible in the original image, and to change viewing angles among different global registered images during the image browsing. The processing of images consists of two main steps: in the first step, the client application uploads an image to the GeoImage Engine which extracts the geo-metadata and returns them back to the client; in the second step, the client application requests augmented content from server, and then renders 3D view of images on the screen of mobile devices.