Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Quantitative Psychology
Measuring Symmetry In Real-World Scenes Using Derivatives Of The Medial Axis Radius Function, Morteza Rezanejad, John D. Wilder, Kaleem Siddiqi, Sven Dickinson, Allan Jepson, Dirk B. Walther
Measuring Symmetry In Real-World Scenes Using Derivatives Of The Medial Axis Radius Function, Morteza Rezanejad, John D. Wilder, Kaleem Siddiqi, Sven Dickinson, Allan Jepson, Dirk B. Walther
MODVIS Workshop
Symmetry has been shown to be an important principle that guides the grouping of scene information. Previously, we have described a method for measuring the local, ribbon symmetry content of line-drawings of real-world scenes (Rezanejad, et al., MODVIS 2017), and we demonstrated that this information has important behavioral consequences (Wilder, et al., MODIVS 2017). Here, we describe a continuous, local version of the symmetry measure, that allows for both ribbon and taper symmetry to be captured. Our original method looked at the difference in the radius between successive maximal discs along a symmetric axis. The number of radii differences in …
Global Estimation Of Signed 3d Surface Tilt From Natural Images, Seha Kim, Johannes Burge
Global Estimation Of Signed 3d Surface Tilt From Natural Images, Seha Kim, Johannes Burge
MODVIS Workshop
The ability of human visual systems to estimate 3D surface orientation from 2D retinal images is critical. But the computation to calculate 3D orientation in real-world scenes is not fully understood. A Bayes optimal model grounded in natural statistics has explained 3D surface tilt estimation of human observers in natural scenes (Kim and Burge, 2018). However, the model is limited because it estimates only unsigned tilt (tilt modulo 180deg). We extend the model to predict signed tilt estimates and compared with human signed estimates. The model takes image pixels as input and produces optimal estimates of tilt as output, using …