CPC G10L 19/0204 (2013.01) [G10L 19/022 (2013.01); G10L 25/45 (2013.01); H03H 17/0266 (2013.01); G10L 21/038 (2013.01)] | 7 Claims |
[ 25. An apparatus for generating audio subband values in audio subband channels, comprising:
an analysis windower for windowing a frame of time-domain audio input samples being in a time sequence extending from an early sample to a later sample using an analysis window function comprising a sequence of window coefficients to acquire windowed samples, the analysis window function comprising a first number of window coefficients derived from a larger window function comprising a sequence of a larger second number of window coefficients,
wherein the window coefficients of the window function are derived by an interpolation of window coefficients of the larger window function; and
wherein the second number is an even number; and
a calculator for calculating the audio subband values using the windowed samples,
wherein the analysis windower is adapted such that the windowing comprises multiplying the time-domain audio input samples x(n) of the frame to acquire the windowed samples z(n) of the windowed frame based on the equation
z(n)=x(n)·c(n)
wherein n is an integer indicating an index of the sequence of window coefficients in the range of 0 to T·N−1, wherein c(n) is the window coefficient of the analysis window function corresponding to the index n, wherein x(N·T−1) is the latest time-domain audio input sample of the frame of time-domain audio input samples, wherein the analysis windower is adapted such that the frame of time-domain audio input samples comprises a sequence of T blocks of time-domain audio input samples extending from the earliest to the latest time-domain audio input samples of the frame, each block comprising N time-domain audio input samples, and wherein T and N are positive integers and T is larger than 4. ]
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