J. J. Gibson, The Perception of the Visual World. Boston, MA: Houghton Mi#in, 1950.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....processing power. Vision based mobility aids projects [5,32] in the 1980s had considerable limitations due to the lack of technology and powerful processors then. # Corresponding author. Tel. 1 905 790 2800x4270; fax: 1 905 790 4400. E mail address: sse mdrobotics.ca (S. Se) Gibson [14] noted that ground plane perception is of vital importance to human and aviation mobility. Quoting from Gibson, there is literally no such thing as a perception of space without the perception of a continuous background surface . His ground theory hypothesis suggested that the spatial character ....

J.J. Gibson, The Perception of the Visual World, Houghton Mifflin, Boston, MA, 1950.

....Shape from Texture, texture gradient, wavelets, warplets. Introduction When observing a static monocular image, we perceive the 3D structure of a scene through a combination of shape cues, especially shading, occlusion and texture. Shape from Texture, rst introduced fty years ago by Gibson [10], studies the recovery of the 3D coordinates of a surface in a scene, by analyzing the distortion of its texture projected in an image [2, 8, 14, 15, 18] The Shape from Texture problem is generally broken down into two independent steps. The rst step is to measure the texture distorsion in the ....

J. Gibson. The Perception of the Visual World. Houghton Miin, Boston, 1950.

....original volume data is reduced to the computation of a particle path in the generated vector field. Also, material flux through an arbitrary surface can be easily determined. 2 Related work The derivation of a vector field from two dimensional image data was introduced as optical flow by Gibson [1]. Optical flow is the CWI, Department of Information Systems, P.O. Box 94097, 1090 GB Amsterdam, Netherlands. E mail wimc cwi.nl distribution of apparent velocities of movement of brightness patterns in an image. It gives information about the spatial arrangement of the objects in the image ....

J.J. Gibson. The Perception of the Visual World. Riverside Press, Cambridge, 1950.

....the way humans and animals perceive it, computational studies are beginning to be devoted to this problem [15] Many synthetic models have been proposed over the years in an attempt to account for the systematic distortion between physical and perceptual space. These range from Euclidean geometry [10] to hyperbolic [18] and affine [25] geometry. Many other interesting approaches have also been proposed, such as the Lie group theoretical studies of Hoffman [11] and the work of Koenderink and van Doorn [16] that are characterized by a deep geometric analysis attempting to discover invariant ....

J. Gibson. The Perception of the Visual World. Houghton Mifflin, Boston, 1950.

....and range of speeds of the motion for the special case of parallel opti cal snow. We demonstrate the effectiveness of the method for both synthetic and real image sequences. i Introduction It has been known for over half a century that optical flow is a strong cue for human visual navigation [Gibson, 1950]. Most studies of optical flow assume that there is a unique velocity vector at each point in the visual field [Koenderink, 1986, Barron et al. 1994] This assumption is only valid over regions of the image in which the depth map is continuous. In this paper we introduce a new natural motion ....

Gibson, J. J. (1950). The perception of the visual world. Houghton Mifflin, Boston.

....This information is converted into local surface orientation, often referred to as a 2 I 2 D sketch [2, 3] or a needle map [4] This paper concentrates on making this 2 1 2 D sketch from texture gradient. This domain, referred to as the shape from texture problem, has been studied extensively [5 12]. Historically, Gibson pointed out the role of texture as a basis for the recovery of surface orientation [5] He proposed the density gradient as the primary basis for surface perception by humans. Formalizing the shape from texture problem requires modeling the image forming system. Mainly two ....

....or a needle map [4] This paper concentrates on making this 2 1 2 D sketch from texture gradient. This domain, referred to as the shape from texture problem, has been studied extensively [5 12] Historically, Gibson pointed out the role of texture as a basis for the recovery of surface orientation [5]. He proposed the density gradient as the primary basis for surface perception by humans. Formalizing the shape from texture problem requires modeling the image forming system. Mainly two kinds of projections have been commonly used: the orthographic projection and the perspective projection. ....

Gibson, J.J., The Perception of the Visual World (Houghton Mitin, Boston, 1950).

....of touch and vision. Much active touch re Figure 1: Ambler search follows from Gibson s [9] observation that when we touch something with our fingers, the skin stimulation depends on the movements that we make. Similarly, recent active vision research (e.g. 1, 2, 3, 11] reflects Gibson s [10] view of fixation, accommodation, convergence, and pursuit as dynamic visual activities. We concentrate on a different modality: contact sensing of forces and torques. To the best of our knowledge, Gibson did not consider this modality, although it would not surprise us to learn that he did. The ....

J. J. Gibson. The Perception of the Visual World. Houghton-Mifflin, Boston, 1950.

....the encoding and representation of images in biological and engineering systems. There is a second, equally important, source of commonality. Vision scientists since Helmholtz have argued that human visual perception is best understood as an explanation of the physical causes of the retinal image [3 5]. By interpreting the retinal images, and not just storing them, biological systems are prepared to generalize from a particular viewpoint, ambient lighting, size, or distance of a specific image. The ability to generalize from acquired data is an important capability for image reproduction ....

J. J. Gibson, The perception of the visual world. Boston: Houghton Mifflin, 1950.

.... is the term for the physiological process by which stereopsis and motion are derived from the different images that impinge on the retina of both eyes, respectively from the changing image that impinges on the retina o f a single eye [79;89] The term was first proposed by Gibson in 1950 [66]. In animals, estimation of optical flow occurs both in the retina and in the cortex (in hominoids predominantly in medial temporal and medial superior t emporal cortex) Physiologically, estimation of optical flow is usually thought to be the equivalent of the computation of spatial and temporal ....

....intensity of image regions remains approximately constant during motion. This notion is called the Optical Flow Constraint Equation [20;78] and can be expressed mathematically as: 0 t It It ####xv x (1) with I(x,t) the image intensity at location x and time t, v the optical flow fi eld [66], #I(x ,t) the spatial intensity gradient (the first order derivative) and I t (x,t) the partial derivative of I(x ,t ) with respect to time. This equation is under determined (note that it has two unknowns, the x and y components o f the vector v in the two dimensional case) so that v ....

Gibson, J. J., The perception of the visual world, Boston: Houghton-Mifflin, 1950.

....Spatial domain filters are the most direct way to capture image texture properties. Early attempts concentrated on measuring the density of edges in an image. Fine textures tended towards a higher density than those of the coarser textures. The Robert s operator and the Laplacian operator [85, 130] are classical edge detectors. Malik and Perona [136] used di#erences of o#set Gaussian (DOOG) functions with a nonlinearity function to model the pre attentive texture perception of the human visual system. The nonlinearity was introduced to discriminate between textures with the same mean and ....

J. J. Gibson, The Perception of the Visual World. Boston, MA: Houghton Mi#in, 1950.

....camera curve (t) and the collision points in the world domain. Right: the projection fi (t) of the camera curve and the projections p of the collision points onto the image domain. the optic flow field is a diverging vector field, of which the singularity is called focus of expansion (FOE) [12][18] An object which is seen in this FOE is located on the future path of the camera (see Fig. 2) Points with a flow vector angle oz 90 or oz 270 will be passed to the left and points with 90 oz 270 will be passed to the right. If the camera is also rotating, the future path, as ....

J.J. Gibson. The perception of the Visual World. Riverside, 1950.

....encoding and representation of images in biological and engineering systems. There is a second equally important source of commonality. Vision scientists since Helmholtz have argued that human visual perception is best understood as an explanation of the physical causes of the retinal image [3] [5]. By interpreting the retinal images and not just storing them, biological systems are prepared to generalize from a particular viewpoint, ambient lighting, size, or distance of a specific image. The ability to generalize from acquired data is an important capability for image reproduction ....

J. J. Gibson, The Perception of the Visual World. Boston, MA: Houghton Mifflin, 1950.

....moment. In this way we can use a sample of spectral moments estimate the vanishing point location. 1 Introduction Shape from texture was identified by Marr as one of the key ingredients of the 2 1 2 Dsketch [4] Moreover, the feasibility of the process is well grounded in psychophysics [7]. From a computational perspective, the main obstacle to practical shape from texture is the fact that the identification of surface markings is in itself insufficient for the recovery of shape from a single image. When posed in a monocular framework the shape from texture problem is ill defined. ....

Gibson J. J. The perception of the visual world. Houghton Miffin, Boston, 1950.

....points occur at local accumulator maxima on the unit sphere. We experiment with the new shape from texture technique on planar textures in buildings. 1 Introduction The perspective foreshortening of surface patterns is an important cue for the recovery of surface orientation from 2D images [2, 7]. Broadly speaking there are two routes to recovering the parameters of perspective projection for texture patterns. The first of these is to estimate the texture gradient[3,11] Geometrically, the texture gradient determines the tilt direction of the plane in the line of sight of the observer and ....

Gibson J. J. The perception of the visual world. Houghton Miffin, Boston, 1950.

....way. We then present a simple generalization of the method that can be used for texture transfer. 1.1 Previous Work Texture analysis and synthesis has had a long history in psychology, statistics and computer vision. In 1950 Gibson pointed out the importance of texture for visual perception [8], but it was the pioneering work of Bela Julesz on texture discrimination [12] that paved the way for the development of the field. Julesz suggested 1 Computer Science Division, UC Berkeley, Berkeley, CA 94720, USA. 2 MERL, 201 Broadway, Cambridge, MA 02139, USA. input images quilting results ....

J. J. Gibson. The Perception of the Visual World. Houghton Mifflin, Boston, Massachusetts, 1950.

....the confidence intervals on the shape estimates in Section 6 and present ideal observer predictions for shape from texture. This work was first reported in (Malik and Rosenholtz, 1993, 1994) 2. Relationship to Previous Work Modern developments in shape from texture originate with the work of Gibson (1950). He coined the term texture gradient to describe the phenomenon in which neighboring surface patches which have identical, or sufficiently similar, texture in the scene project in the image plane to patches with different appearances because of the differences in distance, orientation, and shape ....

Gibson, J. 1950. The Perception of the Visual World. Boston: Houghton Mifflin.

....[18, 19] Secondary information, present in actively and passively moving observers, provides proprioceptive feedback once the subject is moving; sources of secondary information include vestibular and somatosensory signals. Optic flow provides a third source of information concerning self motion [20], but, since optic flow is the same in all conditions in the experiments reported here, we may disregard this source of information for the purposes of this discussion. The main di#erence between the active (act, mism) and passive (pass) movement conditions is that, while both primary and ....

J.J. Gibson. The perception of the visual world. Houghton-Mi#in, Boston, 1950.

....Group (NE20 444) MIT, Cambridge MA 01239. 1 1 Introduction Objects moving in an observer s field of view produce a flow field on the retina. Gibson was one of the first to emphasize that this flow field provides a rich source of information about the environment and our movements within it [11]. More recently, Koenderink and others have shown precisely how the structure of the world is reflected in various properties of the flow field [15] In theory then, we can acquire a great deal of useful information about the 3D world from computations performed directly on this 2D motion pattern. ....

....is reflected in various properties of the flow field [15] In theory then, we can acquire a great deal of useful information about the 3D world from computations performed directly on this 2D motion pattern. This information includes the orientation of surfaces [15, 10] our direction of heading [11, 29], and our time to contact an approaching object [16] The mostfundamental relationship between the structure of the world and the structure of the flow field is smoothness. Simply put, smooth surfaces produce smooth flow [17, 15] This relationship, embodied as a smoothness constraint, is ....

J.J. Gibson. The perception of the visual world. Houghton Mifflin, Boston, 1950.

....is wide enough for the robot. Thus, with respect to these navigational tasks, the virtual corridor is an example of a purposive representation [1] since it only represents the information about the environment necessary for the purpose of executing the navigational tasks. According to Gibson s [7] theory of ecological perception, task related representations should be directly extracted from sensory information. In section 3 we show that the quantities making up the virtual corridor can be easily extracted from the optical flow field. An even more direct pick up [7] of the information is ....

....According to Gibson s [7] theory of ecological perception, task related representations should be directly extracted from sensory information. In section 3 we show that the quantities making up the virtual corridor can be easily extracted from the optical flow field. An even more direct pick up [7] of the information is made possible by the introduction of the polar sector map, which we introduce in section 4. A further property of the set of behaviors is that most of them do not require absolute obstacle distances. It is sufficient if they know an ordinal representation of these distances ....

J. J. Gibson. The Perception of the Visual World. Houghton Mifflin, Boston, MA, 1950.

....specify the u and v feature sets, respectively. A very concrete example in face recognition is that the face chip makes up the attentional features and the rest of the image (which could be used for lighting normalization) makes up the peripheral features. More importantly, there is evidence [3] that this kind of division works in more natural and complex settings. It is second nature for us to utilize the ambient sights and sounds of our immediate surroundings to situate. For example, it is known that people with tunnel vision experience difficulties orienting themselves and responding ....

Gibson, J.J., The Perception of the Visual World. 1950: The Riverside Press.

.... words: optic flow; visual motion; monkeys; self motion; temporal cortex; single unit recording Optic flow fields are generated across the retina as an observer moves through the environment, providing effective cues regarding both the heading of the observer and the structure of the environment (Gibson, 1950; Koenderink and Van Doorn, 1981) Multiple cortical regions are involved in the analysis of motion. Neurons in the middle temporal area (MT V5) respond to motion in a single direction within a small area of the visual field but do not show selectivity for complex motion patterns (Allman et al. ....

Gibson JJ (1950) The perception of the visual world. Boston: Houghton Mifflin.

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J. J. Gibson, The Perception of the Visual World. Boston, MA: Houghton Mi#in, 1950.

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Gibson, J. J. (1950). Perception of the visual world. Boston: Houghton-Mifflin.

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Gibson J. J. The perception of the visual world. Houghton Miffin, Boston, 1950.

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Gibson, J.J. The Perception of the Visual World. Houghton Mifflin, Boston, Mass., 1950.

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J. Gibson. The Perception of the Visual World. Houghton Miin, Boston, 1950.

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Gibson, J. J. (1950). The Perception of the Visual World. Boston, MA: Houghton Mifflin.

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Gibson, J.J. (1950). The Perception of the Visual World. Boston: Houghton Mifflin.

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J.J. Gibson. The perception of the visual world. Houghton-Mi#in, Boston, 1950.

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Gibson, James, The Perception of the Visual World, Houghton Mifflin, 1950.

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J.J. Gibson, The perception of the Visual World, Houton Mifflin, Boston, 1950.

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Gibson, J.J.: The Perception of the Visual World. Houghton Mi#in, Boston (1950)

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J.J. Gibson, The Perception of the Visual World. Boston: Houghton Mifflin, 1966.

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J.J. Gibson. The perception of the visual world. Houghton, 1950.

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Gibson, James, The Perception of the Visual World, Houghton Mifflin, 1950.

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J.J.Gibson.The Perception of the Visual World. Houghton Mifflin, Boston, 1950.

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Gibson, J. J. (1950), The perception of the visual world. Boston: Houghton Mifflin.

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J. J. Gibson, The Perception of the Visual World. Boston: Houghton Mifflin, 1950.

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J.J. Gibson. The Perception of the Visual World. Riverside Press, Cambridge, 1950.

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J.J. Gibson. The perception of the visual world. Riverside Press, Cambridge, 1950.

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J.J. Gibson. The Perception of the Visual World. Riverside Press, Cambridge, 1950.

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Gibson JJ. Perception of the Visual World. Boston: Houghton Mifflin, 1950.

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Gibson, J.J. (1950) The Perception of the Visual World, Houghton Mifflin

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Gibson JJ. The Perception of the Visual World. Boston, MA: Houghton Mifflin, 1950.

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J. J. Gibson, The Perception of the Visual World. Boston, MA: Houghton Mi#in, 1950.

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Gibson, J.J., The Perception of the Visual World, Houghton Mifflin, Boston, MA, 1950.

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J. Gibson. The perception of the visual world. Houghton-Mifflin, Boston, 1950.

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J J Gibson. The Perception of the Visual World. Houghton Mifflin, Boston, 1950.

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J Gibson. The Perception of the Visual World. Houghton Mifflin Co., Boston, USA, 1950. BIBLIOGRAPHY 160

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Gibson, J.J. (1950) The perception of the visual world. Houghton Mifflin, Boston.

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