Spectral graph partitioning provides a powerful approach to image segmentation. We introduce an alternate idea that finds partitions with a small isoperimetric constant, requiring solution to a linear system rather than an eigenvector problem. This approach produces the high quality segmentations of spectral methods, but with improved speed and stability.
1005 with many bumps and valleys of just the right size) could have yield a minimal path on a neighborhood size of 10 which was slightly longer than the (true) minimum path on a larger neighborhood. In practice, however, this limitation has not been a problem. Our experience with distance measurements in monkey visual cortex , which is a highly complicated,… (More)
Previous studies demonstrated substantial variability of the location of primary visual cortex (V1) in stereotaxic coordinates when linear volume-based registration is used to match volumetric image intensities [Amunts, K., Malikovic, A., Mohlberg, H., Schormann, T., and Zilles, K. (2000). Brodmann's areas 17 and 18 brought into stereotaxic space-where and… (More)
The primary visual cortex (V1) can be delineated both functionally by its topographic map of the visual field and anatomically by its distinct pattern of laminar myelination. Although it is commonly assumed that the specialized anatomy V1 exhibits corresponds in location with functionally defined V1, demonstrating this in human has not been possible thus… (More)
Space-variant, or foveating, vision architectures are of importance in both machine and biological vision. In this paper we focus on a particular space-variant map, the log-polar map, which approximates the primate visual map and which has been applied in machine vision by a number of investigators during the past two decades. Associated with the log-polar… (More)
We present a new algorithm for graph partitioning based on optimization of the combinatorial isoperimetric constant. It is shown empirically that this algorithm is competitive with other global partitioning algorithms in terms of partition quality. The isoperimetric algorithm is easy to parallelize, does not require coordinate information and handles… (More)
Previous studies have reported considerable variability in primary visual cortex (V1) shape in both humans and macaques. Here, we demonstrate that much of this variability is due to the pattern of cortical folds particular to an individual and that V1 shape is similar among individual humans and macaques as well as between these 2 species. Human V1 was… (More)