The Observers’ Performance of Detecting Semantic Images from a Complex Background

• Main Authors: Wan -Li Chuang, 莊萬里
• Other Authors: T. J. Hsieh
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/06758264904082046974

碩士 === 中國文化大學 === 資訊傳播學系 === 101 === Due to the drastically growth of visual information in recent decades, people are frequently exposed to vast amount of images. When facing numerous images, identifying any specific image from many irreverent images becomes challenging to the viewer’s visual cognitive capacity. To investigate the behavior of detecting the specific image from complex background, this research mimics a situation happens in everyday life, i.e., to search an image that match a specific theme from the background composed of various images. The researcher carried out two visual searching experiments to examine the effect of certain factors. In the experiment I, the factors including the given image theme, color, visual angle of stimuli size and background distractors were examined. After comparing the correction rate of image theme detection and the self-reported confidence scores, the results show that the different given theme (human action, expressions, arbitrary objects) and viewing angle are two effective factors in correction rate and confidence score, and the other factors are found effective in one of two. The experiment II is also designed as a theme detection task, but theme of target image are constrained in four kinds of facial expressions, happiness, sad, pain and angry. The other factors are similar with that of in experience I. Besides the observation the detection rate and the confidence scores, the detecting behavior of the participants were also recorded by an eye tracker. The results shown that the participants were more sensitive to detect the facial expression representing happiness. The effect of color, viewing angle and distractors types are identical to that of in experiment I. The eye movement pattern, including the fixation time, fixation duration and saccade path, is specifically influenced by the present viewing size of the stimuli.