Patent ID: 6456657
Filing Date: 2002-09-24
Classification: H04B,H04L

Abstract:
Apparatus comprising an encoder for encoding a digital input signal for transmission or storage and a decoder for decoding such encoded signal to reconstruct the input signal, the encoder comprising analysis filter bank means for analyzing the input signal into a plurality of sub-band signals, each sub-band centered at a respective one of a corresponding plurality of frequencies and the decoder comprising synthesis filter bank means complementary to said analysis filter bank means for producing a decoded signal corresponding to the input signal, wherein:the encoder comprises interpolation means interpolating the plurality of sub-band signals to provide a corresponding plurality of interpolated sub-band signals each occupying the same frequency band as the others; and combining means for combining the interpolated sub-band signals to form the encoded signal for transmission or storage; and the decoder comprises means for extracting the interpolated sub-band signals from the received or recorded encoded signal; decimator means for decimating each of the plurality of extracted interpolated sub-band signals to remove the interpolated values and applying the decimated signals to the synthesis filter bank means, the synthesis filter bank means processing the plurality of decimated sub-band signals to reconstruct said input signal.