Received July 16, 1996; Accepted March 3, 1997 | MICHAEL ISARD AND ANDREW BLAKE
The paper "CONDENSATION—Conditional Density Propagation for Visual Tracking" by Michael Isard and Andrew Blake addresses the challenging task of tracking curves in dense visual clutter. Traditional methods like Kalman filtering, which rely on Gaussian densities, are inadequate for this problem because they cannot represent multiple hypotheses simultaneously. The CONDENSATION algorithm introduces "factored sampling," where the probability distribution of possible interpretations is represented by a randomly generated set. This method uses learned dynamical models and visual observations to propagate the random set over time, achieving robust tracking of agile motion. Despite the use of stochastic methods, the algorithm operates in near real-time.
The paper establishes a stochastic framework for tracking curves in visual clutter, focusing on modeling shape and motion. It discusses the limitations of Kalman filters in cluttered environments and the need for a more general probabilistic mechanism to handle multi-modal density functions. The authors propose a temporal propagation of conditional densities, extending the Kalman filter to non-Gaussian densities, which is described by a "Fokker-Planck" equation. This approach allows for the evolution of the density function as a Gaussian pulse, translating, spreading, and being reinforced, thereby providing a more flexible and effective solution for tracking in cluttered scenes.The paper "CONDENSATION—Conditional Density Propagation for Visual Tracking" by Michael Isard and Andrew Blake addresses the challenging task of tracking curves in dense visual clutter. Traditional methods like Kalman filtering, which rely on Gaussian densities, are inadequate for this problem because they cannot represent multiple hypotheses simultaneously. The CONDENSATION algorithm introduces "factored sampling," where the probability distribution of possible interpretations is represented by a randomly generated set. This method uses learned dynamical models and visual observations to propagate the random set over time, achieving robust tracking of agile motion. Despite the use of stochastic methods, the algorithm operates in near real-time.
The paper establishes a stochastic framework for tracking curves in visual clutter, focusing on modeling shape and motion. It discusses the limitations of Kalman filters in cluttered environments and the need for a more general probabilistic mechanism to handle multi-modal density functions. The authors propose a temporal propagation of conditional densities, extending the Kalman filter to non-Gaussian densities, which is described by a "Fokker-Planck" equation. This approach allows for the evolution of the density function as a Gaussian pulse, translating, spreading, and being reinforced, thereby providing a more flexible and effective solution for tracking in cluttered scenes.