What Does Second-Order Vision See in an Image?

The human visual system is sensitive to both first-order variations in luminance and second-order variations in local contrast and texture. Although there is some debate about the nature of second-order vision and its relationship to first-order processing, there is now a body of results showing that they are processed separately. However, the amount, and nature, of second-order structure present in the natural environment is unclear. This is an important question because, if natural scenes contain little second-order structure in addition to first-order signals, the notion of a separate second-order system would lack ecological validity. Two models of second-order vision were applied to a number of well-calibrated natural images. Both models consisted of a first stage of oriented spatial filters followed by a rectifying nonlinearity and then a second set of filters. The models differed in terms of the connectivity between first-stage and second-stage filters. Output images taken from the models indicate that natural images do contain useful second-order structure. Specifically, the models reveal variations in texture and features defined by such variations. Areas of high contrast (but not necessarily high luminance) are also highlighted by the models. Second-order structure—as revealed by the models—did not correlate with the first-order profile of the images, suggesting that the two types of image ‘content’ may be statistically independent.

[1]  G. Sperling,et al.  Drift-balanced random stimuli: a general basis for studying non-Fourier motion perception. , 1988, Journal of the Optical Society of America. A, Optics and image science.

[2]  A. T. Smith,et al.  Direction identification thresholds for second-order motion in central and peripheral vision. , 1994, Journal of the Optical Society of America. A, Optics, image science, and vision.

[3]  Robert J. Snowden,et al.  Orientation bandwidth: The effect of spatial and temporal frequency , 1992, Vision Research.

[4]  A. T. Smith,et al.  Sensitivity to second-order motion as a function of temporal frequency and eccentricity , 1998, Vision Research.

[5]  M. Georgeson,et al.  Sensitivity to modulations of luminance and contrast in visual white noise: separate mechanisms with similar behaviour , 1999, Vision Research.

[6]  D. Macleod,et al.  Contrast-modulation flicker: Dynamics and spatial resolution of the light adaptation process , 1998, Vision Research.

[7]  M. Georgeson,et al.  Does early non-linearity account for second-order motion? , 1999, Vision Research.

[8]  Steven C. Dakin,et al.  Sensitivity to amplitude modulation depends on carrier spatial frequency and orientation , 1998 .

[9]  RussLL L. Ds Vnlos,et al.  SPATIAL FREQUENCY SELECTIVITY OF CELLS IN MACAQUE VISUAL CORTEX , 2022 .

[10]  Shin'ya Nishida,et al.  Dual multiple-scale processing for motion in the human visual System , 1997, Vision Research.

[11]  P. Cavanagh,et al.  Motion: the long and short of it. , 1989, Spatial vision.

[12]  ANDREW T SMITH,et al.  Separate Detection of Moving Luminance and Contrast Modulations: Fact or Artifact? , 1997, Vision Research.

[13]  F. Kingdom,et al.  Sensitivity to orientation modulation in micropattern-based textures , 1995, Vision Research.

[14]  A. Derrington,et al.  Discriminating the direction of second-order motion at short stimulus durations , 1993, Vision Research.

[15]  A. T. Smith,et al.  Motion defined exclusively by second-order characteristics does not evoke optokinetic nystagmus , 1992, Visual Neuroscience.

[16]  David H. Foster,et al.  Role of second- and third-order statistics in the discriminability of natural images , 1997 .

[17]  Andrew T. Smith,et al.  Evidence for separate motion-detecting mechanisms for first- and second-order motion in human vision , 1994, Vision Research.

[18]  A. Derrington,et al.  Second-order motion discrimination by feature-tracking , 1999, Vision Research.

[19]  G. Sperling,et al.  The functional architecture of human visual motion perception , 1995, Vision Research.

[20]  H. Wilson,et al.  A psychophysically motivated model for two-dimensional motion perception , 1992, Visual Neuroscience.

[21]  G. Sperling,et al.  Measuring the spatial frequency selectivity of second-order texture mechanisms , 1995, Vision Research.

[22]  P Perona,et al.  Preattentive texture discrimination with early vision mechanisms. , 1990, Journal of the Optical Society of America. A, Optics and image science.

[23]  Michael S. Landy,et al.  HIPS: A unix-based image processing system , 1984, Comput. Vis. Graph. Image Process..

[24]  J. Bergen,et al.  Texture segregation and orientation gradient , 1991, Vision Research.