This paper suggests the simple higher-frequency band extension (HBE) method based on digital wavelet transform (DWT). The method estimates the missed band through the perceptual coding by using DWT filters. To estimate it from the input signal, the FIR type inverse filter of DWT analysis stage filter is designed. After synthesizing the output wave, we attenuate the overlapped band using the cutoff frequency to get more natural output wave. The method is implemented to behave in real time for variable type of mobile devices such as mobile handsets and mp3 players using ARM9 core as their processing units.
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