BANK OF ANALYSIS FILTERS, BANK OF SYNTHESIS FILTERS, ENCODER, DECODER, MIXER AND CONFERENCE SYSTEM.

摘要

Bank (800, 200) of synthesis filters to filter a plurality of input frames, each input frame comprising M input values ordered and k (0), ..., and k (M-1), where M is a number positive integer and where k is an integer indicating a frame index comprising: a reverse type IV inverted discrete cosine frequency / time converter (810) configured to provide a plurality of output frames, an output frame that comprises 2M output samples ordered xk (0), ..., xk (2M-1) based on the input values yk (0), ..., and k (M-1); a window former (820) configured to generate a plurality of window frames, a window frame comprising a plurality of window samples zk (0), ..., zk (2M-1) based on the equation zk (n) = w (n) ... xk (n) for n = 0, ..., 2M-1, where n is an integer indicating a sample index and where w (n) is a coefficient of real value window function corresponding to the sample index n, an overlap / adder (820) configured to provide an intermediate frame comprising a plurality of intermediate samples mk (0), ..., mk (M-1) based to the equation mk (n) = zk (n) + Zk-1 (n + M) for n = 0, ..., M-1, and an elevator (830) configured to provide an aggregate frame comprising a plurality of aggregate samples outk (0), ..., outk (M-1) based on the equation outk (n) = mk (n) + l (nM / 2) ... mk-1 (M-1- n) and for n = M / 2, ..., M-1 outk (n) = mk (n) + 1 (M-1-n) ... outk-l (M-1-n) for n = 0, ..., M / 2-1, where 1 (0), ..., 1 (M-1) are coefficients of ele vation of real value.