Analog implementation towards artificial post-retinal processing

Information processing in the visual cortex of the mammalian brain allows compact image coding and representation. Neurons found in the primary visual cortex, i.e. the striate cortex, act as localized spatial frequency filters. Receptive field structures found in the visual cortex of the mammalian brain resemble Gabor filters. Systems employing such Gabor filters have been implemented in software for a variety of applications. We believe a hardware implementation of such cells will be useful in artificial visual processing. We previously developed an analog circuit to implement the Gabor function, but the circuit did not perform some of the complex spatial dilation needed. We now report a new circuit that accomplish these critical characteristics and mimic the simple cell function in the striate cortex