BIB-VERSION:: CS-TR-v2.0 ID:: STAN//CS-TR-00-1631 ENTRY:: April 14, 2000 ORGANIZATION:: Stanford University, Department of Computer Science TITLE:: Early Vision Using Distributions TYPE:: Thesis TYPE:: Technical Report AUTHOR:: Ruzon, Mark A. DATE:: April 2000 PAGES:: 121 ABSTRACT:: For over thirty years researchers in computer vision have been proposing new methods for performing ``early vision'' tasks such as detecting edges and corners. One key element shared by most methods is that they represent local image neighborhoods as constant in color or intensity, with deviations modeled as noise. Due to computational considerations that encourage the use of small neighborhoods where this assumption holds, these methods remain popular. This research models a neighborhood as a distribution of colors. Our goal is to show that the increase in accuracy of this representation translates into higher-quality results for early vision tasks on difficult, natural images, especially as neighborhood size increases. We emphasize large neighborhoods because small ones often do not contain enough information. We emphasize color because it subsumes greyscale as an image range and because it limits the number of valid models we should consider; using only greyscale images allows assumptions that do not hold for color. We discuss distributions in the context of three related image boundary tasks: edge detection, corner detection, and estimating alpha, or the percentage with which two colors from two objects mix to form the color of a pixel at a boundary. NOTES:: [Adminitrivia V1/Prg/20000414] END:: STAN//CS-TR-00-1631