Perceiving Animacy and Arousal in Transformed Displays of Human Interaction 1 Phil McAleer, 2 Barbara Mazzarino, 2 Gualtiero Volpe, 2 Antonio Camurri, 1 Kirsty Smith, 1 Helena Paterson, 1 Frank E. Pollick 1 Department of Psychology, University of Glasgow, Glasgow, Scotland, 2 Infomus Lab, D.I.S.T, University of Genova, Genova, Italy Experiment 1a & 1b – Dance Scenarios Experiment 2 – Social Scenarios Conclusion Introduction Heider and Simmel (1944) showed that people, on viewing a simple animation involving geometric shapes (a disc, a large triangle and a small triangle), would attribute emotions and intentions to the shapes based on their movements. Further experiments have used the technique of varying simple mathematical relationships of the shapes. These experiments have shown that the attribution of animacy is largely due to changes in speed and direction of the shapes, rather than characteristic features. We introduce a new method to create animacy displays direct from actual human movements. We examined the perception of animacy using transformed displays of human interactions, and it was our intent that this would allow new insights as to how visual cues lead to spontaneous use of animate terms and the attribution of social meaning. Stimulus Production 1a. Stimuli & Design Footage depicts two men performing a dance routine. 4 experimental conditions: Real, Body Silhouette, Pulsing Block, Block. 36 subjects used in a between design: 9 per condition. 1b. Stimuli & Design Footage depicts one man performing a dance routine 4 experimental conditions: Real, Body Silhouette, Pulsing Block, Block. 36 subjects used in a between design: 9 per condition. 6 new scenarios were filmed: 4 involving interactions between two people, such as chasing, following, and circling; 2 involving a single person walking or jogging. Stimuli & Design 9 scenarios were used in total: 6 new scenarios, the scenarios from Experiments 1a & 1b, and a representation of Heider and Simmel (Nevarez & Scholl, 2000). 4 experimental conditions: Real, Body Silhouette, Pulsing Block, Block. 32 subjects used in a between design: 8 per condition. The scenario depicted (right) resulted in the largest occurrence of animate terms, after the Heider and Simmel display. Using this new technique for stimulus generation from real video footage, we were able to create an abstract display, involving geometric shapes, that resulted in animate terms being used to describe it. References Camurri A., Mazzarino B. & Volpe G. Analysis of Expressive Gesture: The EyesWeb Expressive Gesture Processing Library, in A. Camurri, G. Volpe (Eds.), Gesture-based Communication in Human-Computer Interaction, LNAI 2915, Springer Verlag. (2004). Heider, F., & Simmel, M., An Experimental Study of Apparent Behavior, American Journal of Psychology, 57:2, (1944). McAleer, P., Mazzarino, B., Volpe, G., Camurri, A., Smith, K., Paterson, H., Pollick, F.E., Perceiving Animacy and Arousal in Transformed Displays of Human Interaction. Proceedings for ISHF_MCM_2004, in press. Available from Nevarez, H.G., & Scholl, B.J., (2000). Tasks & Results Subjects asked for a free response. Average on-line rating of emotional engagement using a slider. Tasks & Results Subjects asked for a free response. Self-propulsion rating. Average on-line rating of arousal using a slider. Tasks & Results Subjects asked for a free response. 1. Real Video – original footage. 2.Body Silhouette – obtained by the removal of colour information and applying a background subtraction technique to the input video. 3.Pulsing Block(s) – movement of a person is represented by a rectangle, the size of which is related to the Quantity of Motion (QoM) as measured by algorithms included in the EyesWeb Expressive Gesture Processing Library. QoM is computed as the change in area of the person, in the silhouette format, from one frame to the next, summed on the last few frames (4 frames in this experiment). QoM can be assumed as a measure of the global amount of detected motion and it can be thought of as a first rough approximation of the physical momentum. 4.Block(s) – uses techniques for the tracking of the centre of mass of the silhouette image for each respective person. The dimensions of the block for each person in this condition were constant. Each experiment involved creating four displays of the same scene but with decreasing amounts of visual information available. The original footage was captured using a digital video camera. Next, through use of the EyesWeb open platform for multimedia production and motion analysis ( the four experimental conditions were created: (McAleer, Mazzarino, Volpe, Camurri, Smith, Paterson, Pollick, 2004)