Three-channel amplitude compression followed by frequency shaping was used to process test sentences for five profoundly deaf subjects, and the recognition scores were compared to scores achieved with frequency shaping only. At preferred levels, the scores of three of the five subjects showed a statistically significant but not dramatic advantage for compression; the averages of the scores for ...

We present a feature extraction technique based on static and dynamic modulation spectrum derived from long-term envelopes in sub-bands. Estimation of the sub-band temporal envelopes is done using Frequency Domain Linear Prediction (FDLP). These sub-band envelopes are compressed with a static (logarithmic) and dynamic (adaptive loops) compression. The compressed sub-band envelopes are transform...

The goal of this paper is to analyze the impact of codecdegraded speech on a state-of-the-art speaker recognition system and propose mitigation techniques. Several acoustic features are analyzed, including the standard Mel filterbank cepstral coefficients (MFCC), as well as the noise-robust medium duration modulation cepstrum (MDMC) and power normalized cepstral coefficients (PNCC), to determin...

A network covert channel is a passage along which information leaks across the network in violation of security policy in a completely undetectable manner. This paper reveals our findings in analysing the principle of G.723.1 codec that there are ‘unused’ bits in G.723.1 encoded audio frames, which can be used to embed secret messages. A novel steganalysis method that employs the second detecti...

This study investigated the perceptual adjustments that occur when listeners recognize highly compressed speech. In Experiment 1, adjustment was examined as a function of the amount of exposure to compressed speech by use of 2 different speakers and compression rates. The results demonstrated that adjustment takes place over a number of sentences, depending on the compression rate. Lower compre...

This paper proposes sparse and redundancy representation spectral domain compression of the speech signal using novel sparsing algorithms to the problem of speech compression (SC)/enhancement (SE). In Automatic Speaker Recognition (ASR) sparsification can play a major role to resolve big data issues in speech compression and its storage in the database, where the speech signal can be uncompress...

This paper presents an alternative solution for speech database compression aiming at the embedded application of concatenative synthesis systems. The waveform of a speech segment is firstly decomposed into a prosodic pattern and a spectral pattern by STRAIGHT – a powerful speech analysissynthesis algorithm. Then all the prosodic and spectral patterns are clustered respectively to remove the re...

A network covert channel is a passage along which information leaks across the network in violation of security policy in a completely undetectable manner. This paper reveals our findings in analysing the principle of G.723.1 codec that there are ‘unused’ bits in G.723.1 encoded audio frames, which can be used to embed secret messages. A novel steganalysis method that employs the second detecti...

We describe a method and an implementation for producing a highly compressed representation of speech, in the order of 40 bps. This compression method uses a speech recognition engine to analyze the speech signal at the morphological level, i.e. the words. The words are then coded using a wordlevel text compression mechanism. After decompression, the speech message is recovered using Text-To-Sp...

The purpose of this study is to determine the just noticeable differences (JNDs) for speech rate. The results are intended to be used for the design of an interactive speech speed control. The JND at three different speech rates was determined using the psychophysical method of constant stimuli. Speech stimuli were compressed using the SOLA time-compression technique. The findings show a signif...