SIGMA: A Framework for Image Understanding - Integration of Bottom-Up and Top-Down Analysis

The framework and control structure of an image understanding system SIGMA arc presented. SIGMA consists of three experts: Gelmetric Reasoning Expert (GRE) for spatial reasoning. Model Selection Expert (MSE) for appearance model selection, and Low level Vision Expert (LIVE) for knowledge-based picture processing. Tills paper mainly describes the control mechanism for the spatial reasoning by GRE, where bottom-up and top-down analyses are integrated into a unified reasoning process.