By reformulating the multi-channel filterbank as single-in single-out linear periodically time-varying system

a memory-scalable implementation of generic tree-structured filterbanks (GTSFB) is presented that produces exactly the same subband coefficients as the global implementation of GTSFBs.Both the forward and inverse transforms of the proposed approach have low-memory requirements unrelated to the signal length.Additionally

the majority of the memory budget can be distributed freely between the forward and inverse transforms

which is highly desirable for the applications where the memory asymmetry exists between the analysis/synthesis systems.