A Brief Review on LPC and VELPC techniques for Speech Compression

In this paper, we have presented a brief review of the most effective and popular technique for speech compression i. e. LPC (Linear Predictive Coding) technique and its modified version i. e. VELPC (Voice Excited Linear Predictive Coding) technique. LPC is one of the most powerful speech coding technique and it is used widely for encoding speech signal at a low bit rate since it provides extremely accurate estimates of speech signal parameters. Though, it is a lossy technique but then also the output is easily understandable. Another method based on LPC technique which is its modified version is VELPC. VELPC eliminates the drawback of LPC technique. VELPC avoids the imprecise detection of the pitch parameter and voiced/unvoiced decision flag rather it generates an innovation signal instead.