A Modified Inexact Arithmetic Median Filter for Removing Salt-and-Pepper Noise From Gray-Level Images.

We have recently proposed approximate median filters (APMFs). They are based on the sorting network and achieve acceptable image quality under low-cost hardware. In this brief, we develop a specific comparator to improve the capabilities of those filters in noise elimination. The architecture of our inexact median filters (IMFs) is regular and modular. Also, we introduce the histogram-based error dispersion plot as a new error evaluation method to have a better assessment of IMF performance. Simulation results show that the proposed filter is effectively low cost in power, area, and speed. Despite the tradeoff between the filtering accuracy and circuit characteristics, the output quality of the filter is largely similar to that of the precise one. Also, the degradation is almost not noticeable to the human eye. [ABSTRACT FROM AUTHOR]