On Symmetric Extensions, Orthogonal Transforms of Images, and Paraunitary Filter Banks
نویسندگان
چکیده
Periodic or symmetric extensions are commonly used for processing images and other finitelength signals with a paraunitary Alter bank (PUFB). Unlike infinite-length signals, PUFBs applied to finite-length signals will not necessarily lead to an orthogonal system. We show that for symmetric extensions, orthogonality is only possible for special PUFBs based on linearphase Alters. We also discuss implementation issues.
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