Quantization Noise Power Injection In Subband Audio Coding Using Low Selectivity Filter Banks

نویسنده

  • D. MARTÍNEZ
چکیده

The ISO-MPEG standards are widely used for high quality audio coding. They use perceptual models that require high frequency resolution. This implies two characteristics: they use high selectivity filter bank to decompose the audio signal, and the FFT frame length for the frequency masking threshold calculations is long. Both characteristics carried out a very high delay coding. In applications where the delay is a critical parameter, i.e. when the use of a feedback channel is important, the ISO-MPEG algorithms are not suitable. In this paper we present how to overcome the first handicap: to compatibilize the use of short impulse filter bank response and perceptual model application. These filter banks present low selectivity and so the non-ideal filters frequency responses should be taken into account. Key-Words: Subband audio coding, Noise injection, Filter bank, Psycho-acoustic model

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تاریخ انتشار 2004