Nonlinear spatio-temporal noise suppression techniques with applications in image sequence processing

Statistical properties of the spatiotemporal center weighted median (CWM) filter for image sequences are investigated. It is statistically shown that the CWM filter preserves image structures under motion at the expense of noise suppression. To improve the CWM filter, an adaptive CWM (ACWM) filter having a variable central weight is presented. It is shown that the ACWM filter can preserve image structures under motion while suppressing noise, and thus can be effectively used in image sequence filtering