Some High-Efficiency Two-Dimensional Digital Filters with Application to Biomedical Image Processing

Summary

Efficient two-dimensional digital filters are presented for biomedical image processing. In particular FIR digital filters, designed through the window method, and IIR digital filters, defined by cascading a number of elementary filters or through suitable transformation-stabilization procedures, are described. The application of these digital filters to biomedical image processing is presented, to perform image smoothing or enhancement and reduce the amount of data. For this last purpose the combined use of digital filters and fast digital transformations (FFT, FWT) is described to obtain two main results: better quality images, data amount reduction. A digital filtering technique is also presented, which allows the selective filtering of conventional radiographs, in order to obtain depth-dependent information (digital tomographic filtering). Experimental results are reported.