Methods and filter bank device to implement the filter bank

摘要

Complex analysis filter bank is implemented by obtaining an input audio signal as a time-domain input samples a plurality of N. The addition and subtraction of each pair of time-domain input samples is performed to obtain the intermediate samples of the first and second groups, each group has a middle N / 2 samples. The sign of the intermediate sample that has been indexed by odd in the second group are reversed. To obtain the output coefficients of the first group in the frequency domain, the first transformation is applied to the intermediate sample of the first group. To obtain the output coefficient of the intermediate second group in the frequency domain, the second transformation is applied to the intermediate sample of the second group. To obtain the output coefficient of the intermediate second group, the order of coefficients in the output coefficients of the intermediate second group are reversed. Power coefficient, the first group and the second group may be transmitted and / or stored as a frequency domain representation of the audio signal.