On the design of quadratic filters with application to image processing
S.V. Uppala, John D. Sahr · IEEE Transactions on Image Processing · 1997
We present a systematic design method for quadratic filters, and show an example for an edge detector. Our design maximizes the output signal-to-noise ratio (SNR) constrained to detect desired signals while ignoring specified error signals such as shot noise. This filter compares favorably with Sobel and morphological detectors of similar complexity.