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Visual, Tactile, and Olfactory Displays
Published in Nancy J. Stone, Chaparro Alex, Joseph R. Keebler, Barbara S. Chaparro, Daniel S. McConnell, Introduction to Human Factors, 2017
Nancy J. Stone, Chaparro Alex, Joseph R. Keebler, Barbara S. Chaparro, Daniel S. McConnell
Stereopsis refers to the perception of relative depth that is perceived by the slightly different views of the world perceived by our two laterally displaced eyes. You can see the differences in these views by alternately closing one eye at a time while viewing your index finger at arm’s length. You will notice there is a slight shift in the position of your finger relative to the background in the scene.
Introduction to Computer Vision and Basic Concepts of Image Formation
Published in Manas Kamal Bhuyan, Computer Vision and Image Processing, 2019
Applications of Stereo Vision: “Stereopsis” refers to the process of depth perception using binocular vision. Some of the advantages of stereo vision setups are listed as follows: Two cameras of stereo vision setup provide wider FOV as compared to single camera-based system. Wider FOV is needed in many computer vision applications, like visual surveillance, autonomous vehicle [23], etc.Disparity map gives information of the position of the objects in the real world scene. Small disparity value means the object is farther from the camera, whereas larger disparity value indicates that the object is nearer to the camera. In other words, objects nearer to the camera undergo more displacement than the objects away from the camera. This property can be used in accurate object segmentation. So, segmentation would be independent of colour, and hence the constraint of colour dissimilarity between the foreground and the background is removed [194]. Figure 1.42 shows one example of image segmentation using disparity information. In this figure, the stereo images, their corresponding disparity map, image segmented using only colour information, and the image segmented using disparity information are shown separately. The image consists of two cones having similar colour enclosed by a square box. When the image is segmented using colour information, these two objects are segmented as a single object as shown in Figure 1.42(d). On the other hand, they are segmented as two different objects by utilizing the three-dimensional information as shown in Figure 1.42(e). These two objects have different disparity values in spite of having similar colour, which can be seen in Figure 1.42(c).The size of an object, distance between two objects, and distance of an object from the camera can be determined in a stereo vision setup.The three-dimensional information obtained from stereo images enables us to understand the complex scenes in a better way. So, stereo vision can be used for the applications such as robot navigation, objection detection, and tracking, etc.Stereo vision provides an efficient perception of objects having curved surfaces.
Basketball free-throws performance depends on the integrity of binocular vision
Published in European Journal of Sport Science, 2020
Jesús Vera, Ruben Molina, David Cárdenas, Beatríz Redondo, Raimundo Jiménez
Nevertheless, beyond the relevance of visual acuity, a precise cortical integration of the stimuli perceived from both eyes, namely binocular vision, is required for the existence of superior visual skills (i.e. stereopsis). For acceptable levels of sports performance, an appropriate functioning of these superior visual abilities is required, especially in those sport disciplines in which the ability to judge spatial localisation accurately and discriminate distance information is needed (Erickson, 2007; Mazyn, Lenoir, Montagne, & Savelsbergh, 2004). A broad range of ocular conditions such as anisometropia, aniseikonia, cataract or glaucoma are known to provoke binocular rivalry, and thus, affect binocular vision (Blake & Wilson, 2011; Holopigian, Blake, & Greenwald, 1986; Jiménez, Ponce, & González-Anera, 2004; Jiménez, Ponce, Jiménez Del Barco, Díaz, & & Pérez-Ocon, 2002; Park, Kim, & Lee, 2018; Rutstein, Fullard, Wilson, & Gordon, 2015). Significant deficits in motor performance have been observed in abnormal binocular vision conditions (O’Connor, Birch, Anderson, & Draper, 2010), monocular viewing conditions (Gonzalez & Niechwiej-Szwedo, 2016) or degraded binocular vision (Piano & O’Connor, 2013) in different contexts. It has been argued that individuals with congenital or early deteriorated binocular function develop compensatory strategies (i.e. use of monocular cues) over time in order to circumvent this impairment (Howard & Rogers, 2002). However, to date, there are no studies that have investigated the effects on sports performance of interocular differences in the images perceived when the binocular vision is acutely altered, specifically on basketball free-throws performance. There is scientific evidence that an unequal balance between eyes is commonly presented, with this interocular imbalance having a negative impact on different visuo-motor skills (Gonzalez & Niechwiej-Szwedo, 2016; O’Connor et al., 2010; Piano & O’Connor, 2013). Therefore, we consider of interest to assess the potential detrimental effects of interocular imbalance in sports performance.