Visual Cognition research group Contact Information

Principal Investigator, University Researcher
Jukka Häkkinen
Institute of Behavioural Sciences
PO Box 9 (Siltavuorenpenger 1 A)
FI-00014 University of Helsinki
+358 - 9 - 1911
e-mail:
Jukka.Hakkinen@helsinki.fi

 

The focus of our research group is in visual cognition, focusing specially to virtual reality, perception of natural images and applying vision science to advanced display technologies.

Virtual reality

Our team has a long history of studying head-mounted displays and virtual reality. Jukka Häkkinen has studied sickness symptoms with various consumer head-mounted displays and use cases (see articles 1, 2, 3, 4, 5, 6, 7). Later we studied how well head-mounted displays can be used in everyday environment (see articles 1, 2, 3).

As the virtual reality and 360-videos are now making a breakthrough in various domains, we are focusing our research efforts to this area. In April 1st 2016 we started a research cooperation with professor Takashi Kawai from Waseda University, Japan. The starting point of our cooperation is a seminar "New opportunities from Finnish-Japanese collaboration in virtual reality and 360 video" that we will arrange in 1st of June.

We have also started a technical committee on Advanced Imaging in International Ergonomics Association to promote international cooperation in the area.

Material and software distribution

VQone Matlab toolbox

We just published an article related to the VQone Matlab toolbox thatwe are using in our image quality experiments. The toolbox is freely available here.

CID2013 Database

The Camera Image Database CID2013 can be downloaded here

Characterizations of the displays in our labs are available here

The CVD2014 video database is available here

Current projects

Mind, Picture, Image (MIPI)

MIPI is an Academy of Finland project in which aim to understand how cultural meanings and signification emerge in the visual processing. We focus to the properties of visual gist and its role in the gaze control. The project is a cooperation project with Tampere Research Centre for Journalism, Media, and Communication (COMET), University of Tampere and Visual Interaction Research Group (VIRG), University of Tampere.

Computational Psychology of Experience in Human-Computer Interaction (COPEX)

COPEX is an Academy of Finland project, which aims to study touch and gesture interaction with biomechanics measurements, eye-movement tracking and experience measurement to get an understanding how users experience new interaction technologies. The data is modeled with Bayesian network, which can reveal relationships between different attributes and parameters via backwards reasoning. The project is a cooperation project with Machine VIsion and Pattern Recognition Laboratory, Lappeenranta University of Technology.

Formation of visual preferences

This involves three subprojects, mostly funded by UCIT, doctoral program on user-centered information technology.

1. Visual preferences: processes and subjective experiences

Our focus is on strategies used when estimating natural visual scenes both from the perspective of task (top-down influence) as well as the changes in the scenes (bottom-up influence). The goal is to understand the requirements and the process of preference judgements. The main question to answer is how does the process of a quality task differ from other tasks. The methods used are qualitative estimations, eye tracking and electroencephalography (EEG) combined with experimental study design. Part of the project is done in collaboration with Technical University of Berlin.

2. Analytic and non-analytic processes in visual judgments

Judgments can be made either non-analytically by relying on the fast holistic responses or analytically by relying on the featural analysis of the stimuli and the summation of the utility of the different features. This sub-project compares the role of these modes when participants are either asked to give explanations for their judgments or asked to make judgments without explanation. Experimental methods and quantitative analysis of the judgments and explanations are used to examine the associations between quality of the judgments, thinking modes and participants' explanations.

3. Component dimensions of preference evaluation task

Visual stimuli can be broken down into its components. Some can be easily distinguished from each other while others are more integral e.g. color saturation and hue. How is this affecting on how we perceive and evaluate preference of images? Are some image artefacts more separable than others and does that affect in the decision making process of quality evaluation. The aim of this project is to understand how the distinction of separable and integral components affect the preference estimation task.

Image quality

In Psychology of Evolving Media and Technology (POEM) project we research the development of the image processing components and digital cameras. This requires knowledge of the ways people perceive and experience the differences in images and video (Radun et al. 2010, Virtanen et al, 2008) and how they judge these differences in quality evaluation. We have studied methods and algorithms for measuring the quality attributes of natural images (Nuutinen et al, 2010, 2011, 2012) or video (Nuutinen et al, 2013). As part of the image quality studies we are developing subjective image and video quality evaluation methods and databases. To develop and test the performance of various quality assessment algorithms or models, true subjective evaluations are the necessary yardstick to set them against. The databases will be freely available for the research community and are downloaded here.

Cognitive processes and the use of head-mounted displays

Head-mounted displays provide interesting possibilities for various use cases, as interest for Google Glass has shown. However, using an HMD is actually a complex multitasking situation, which might affect the performance and safety of the user. In our recent study we show how attention and cognitive load affect walking and task performance with head-mounted display (Mustonen et al, 2013). In another study we investigate, what are the most effective visualization techniques with stereoscopic augmented reality (Kytö et al, 2012).

In our earlier studies we have investigated the eye strain caused by HMDs in uses cases like e-book reading (Pölönen et al, 2012) and game playing (Häkkinen et al, 2006).

Viewing stereoscopic contents

When viewing stereoscopic 3D contents, there are multiple factors that affect the viewing experience (Pölönen et al, 2009, 2012). Firstly, the stereoscopic display have a significant effect to the quality of experience (Häkkinen et al, 2009; Salmimaa et al, 2009; Pölönen et al 2011). Secondly, quality of experience is affected by the way stereoscopic images are captured (Kytö et al, 2012), scaled (Häkkinen et al, 2011) or compressed (Aflaki et al, 2010, 2011) .

Social cognition

The interaction between people includes also non verbal communication. Gaze and gestures are an important part of it. We examine interpersonal communication with the help of video analysis and eye tracking. This approach has resulted in a practice course of Multimodal methods in Interaction Analysis. The goal of the course is to introduce different experimental designs as well as analysis methods in the context of interpersonal communication for students.

User Experience in Digital Games

Digital games, that is mobile, PC, and console games are the biggest form of entertainment in the world today. Games elicit numerous consequences and outcomes that are mediated by the experience the game provides to gamer. The key to better understand the game-gamer relationship is to study the psychological roots of the user experience (UX) in games (Takatalo, 2011). To date, we have investigated UX in different games (Takatalo et al., 2006), display technologies (Takatalo et al. 2006, 2011) and context of play (Takatalo et al., 2008), for example.

Psychology in University of Helsinki

University of Helsinki