Analog VLSI weighted median filters

The implementation of CMOS VLSI weighted median filters for image and signal processing analysis using analog circuits is presented. The presented weighted median filter uses a transconductance comparator as a basic cell. The output saturation current characteristic of the transconductance comparator allows modification of the saturation current to be used in weighted order filters. Experimental results of the transconductance comparator are shown. Simulation results of an 249 × 209 image corrupted with 15% salt and pepper noise, was used to test the weighted median filter. All the simulations were made using SPICE BSIM3 level 49 model and 1.2 μm MOSIS parameters