Research on Image Median Filtering Algorithm and Its FPGA Implementation

Image filtering plays an important role in image preprocessing. The median filters, including the standard median filter and the multi-level median filter, which can preserve image features and thin lines are introduced and discussed in detail. After that, the FPGA based solution for the algorithms of these two filters are presented. This paper also gives account to the FPGA implementation of the complete structure of a general filter including the filtering window generating module and the row-column counting module. RTL level simulation is performed in Modelsim to verify the functional correctness and system level simulation is performed in Matlab to compare the filtering effect.