High school
Pages 4 (1004 words)
Download 0
Abstract Sub-band coding (SBC), a method used to encode signals, is a more efficient form of transform coding strategy compared to other systems. The purpose of this paper is to describe a sub-band coding system intended for digitally encoded speech or audio signals.


Index terms-- template, markup, discount I. INTRODUCTION The degree to which the bit rate can be reduced or compressed without impairing the quality of the decoded signal strongly determines the efficiency of an encoding technique. Typically, speech and audio signals have a high degree of redundancy which may be exploited to reduce the bit rate. In addition, the human auditory system possesses certain properties which may be useful in reducing the bit rate without compromising the quality of the decoded signal. 1 To take advantage of the aforementioned properties, a variety of techniques have been developed to efficiently represent speech and audio signals in digital form for either transmission or storage purposes. Since two different sub bands in each signal exist, the lower-frequency band and high-frequency band, and most of the energy in the signal is contained in the lower frequencies, it is possible to encode the lower-frequency band with more bits than the high-frequency band. Sub-band coding is a powerful approach where a speech or audio signal is broken down into several frequency bands and each band is digitally encoded separately. 2 II. Sub-Band coding implementation Figure 1 shows the basic configuration of the two- band sub-band design. The input signal represented as xi (n) is divided into two equally spaced frequency bands by low pass filter and high pass filter, represented as H1 and H2 respectively. ...
Download paper
Not exactly what you need?