High-Quality Audio Bandwidth Extension Method Based on LPC

• Main Authors: Tzu-Yi Wu, 吳子懿
• Other Authors: Sheau-Fang Lei
• Format: Others
• Language: en_US
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/12271494186827945032

碩士 === 國立成功大學 === 電機工程學系碩博士班 === 94 === The development of digital audio in the past years, it becomes an important tool for people to share music and audio. For example, MP3 is the most popular one. However, the request of compression ratio is getting higher for every application in recent, even it needs lower bit rate from 192kbps to 64kbps. The low bit rate causes distortions in high band component of audio signals and makes listening flatness and muffled. Bandwidth extension is a new technology in the recent years. It designs a processing method different from traditional perceptual audio coding. According to the different sensitivity to different frequency in human auditory system, it uses a little information to reconstruct the lost high band component and makes low bit rate audio streams without losing audio quality. Our researches also focus on bandwidth extension technology. We proposed a method using linear prediction to record original high band component in the encoder and reconstruct a rough high band component similar to the original component. It can be combined with traditional perceptual audio coder to overcome the distortion in high band and reaches the goal of low bit rate with high quality of new digital audio coding.