Unequal Length First-Order Linear-Phase Filter Banks for Efficient Image Coding
In this paper, we present the structure and design method for a first-order linear-phase filter bank (FOLPFB) which has unequal filter lengths in its synthesis bank (UFLPFB). A FOLPFB is a generalized version of biorthogonal LPFBs regarding their synthesis filter lengths. Ringing artifact is the main disadvantage of image coding based on FOLPFBs. UFLPFBs can reduce the ringing artifacts as well as approximate smooth regions well.