Real-time Gabor-type filtering using analog focal plane image processors

We describe focal plane image processors which filter images in space by filters which are similar to even and odd Gabor filters. All processing is done using analog circuits fabricated on the same die as the photosensors allowing combined sensing and processing at rates as high as 5000 frames per second. Both 1D and 2D sensors have been designed, fabricated and tested. In the 2D sensor the tuned orientation can be steered and the filter response scaled by adjusting external bias voltages controlling parameters such as the gains of the analog processing circuits. Because both even and odd Gabor-type filter outputs are calculated, sensors can be used in Gabor phase-based algorithms. As a simple example, we have embedded a 1D sensor on a mobile robot platform to perform image fixation.

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