The paper presents a novel technique for underwater acoustic voice communications. The speech signal is compressed prior to transmission by using Linear Predictive Coding and transmission of appropriate speech parameters is achieved by Digital Pulse Position Modulation. The main emphasis here is on the reception of the multipath-dominant signal and on the demodulation process.

We propose a new approach to nonuniform time compression, called Mach1, designed to mimic the natural timing of fast speech. At identical overall compression rates, listener comprehension for Mach1-compressed speech increased between 5 and 31 percentage points 2 over that for linearly compressed speech, and response times dropped by 15%. For rates between 2.5 and 4.2 times real time, there was ...

A Concatenative Text-To-Speech (CTTS) synthesizer requires a large acoustic database for high quality speech synthesis. This database consists of many acoustic leaves, each containing a number of short, compressed, speech segments. In this paper we propose two algorithms for re-compression of the acoustic database, by re-compressing the data in each acoustic leaf, without compromising the perce...

This paper examines the impact of lossy speech coding with Speex on GMM-UBM speaker recognition (SR). Audio from 120 speakers was compressed with Speex into twelve data sets, each with a different level of compression quality from 0 (most compressed) to 10 (least), plus uncompressed. Experiments looked at performance under matched and mismatched compression conditions, using models conditioned ...

BACKGROUND Older adults manifest difficulties in speech perception, especially when speech is accompanied by noise or when speech is rapid. Several explanations have been suggested to account for age-related changes in speech perception, such as changes in hearing sensitivity or a more general decline in cognitive functioning. The purpose of the present study was to directly examine the relativ...

The automatic recognition of MP3 compressed speech presents a challenge to the current systems due to the lossy nature of compression which causes irreversible degradation of the speech wave. This article evaluates the performance of a recognition system optimized for MP3 compressed speech with current state-of-the-art acoustic modelling techniques and one specific front-end compensation method...