The authors presents an algorithm for computing two-dimensional convolution filters that can detect characters and other image features by generalizing the previously derived one- dimensional Wiener Spike Filter. The author motivates the technique of Wiener Spike Filter design, provides a formal derivation for the two-dimensional generalization, gives a sample example, and describes the results of applying the technique to the task of detecting and recognizing specific English characters. The procedure can be easily adapted to recognize any specific feature that can be expressed as an image.
Eric C. Rosen,
"Feature detection using 2D Wiener spike filters", Proc. SPIE 2028, Applications of Digital Image Processing XVI, (20 October 1993); doi: 10.1117/12.158636; https://doi.org/10.1117/12.158636