Enhancement of differentially coded speech signals by means of quantization error correction
نویسنده
چکیده
A method to increase the Signal—to—Noise Ratio (SNR) of speech codecs is presented. It has been applied to Adaptive Delta Modulation (ADM) according to Jayant's algorithm. Observations indicate that bit streams resulting from these coders and quantization errors are correlated to some extend. Based on this experience a Quantization Error Correction method (QEC) has been developed that improves the SNR of the output signal. With this method the decoder output is updated with a correction signal derived from the received bit sequence. An expression for the optimal correction level is derived. Application of the method by means of computer simulation and hardware implementation gave a 5 to 6 dB increase in SNR. There is no need to transmit additional information and a normal decoder can be used together with additional circuitry.
منابع مشابه
A New Method for Speech Enhancement Based on Incoherent Model Learning in Wavelet Transform Domain
Quality of speech signal significantly reduces in the presence of environmental noise signals and leads to the imperfect performance of hearing aid devices, automatic speech recognition systems, and mobile phones. In this paper, the single channel speech enhancement of the corrupted signals by the additive noise signals is considered. A dictionary-based algorithm is proposed to train the speech...
متن کاملCompression of Speech Signals using MSVQ and its Enhancement Using Spectral Subtraction & Kalman filter and its performance comparisions
Coding algorithms seek to minimize the bit rate in the digital representation of a signal without an objectionable loss of signal quality in the process. Speech enhancement means improvement in intelligibility and/or quality of a speech signal. This paper deals with multistage vector quantization technique used for coding of narrow band speech signals. The parameter used for coding of speech si...
متن کاملUsing FFI Interpolator and VQ Quantization for Designing of High Quality 1200 BPS Speech Vocoder
Storaging or transmission of speech signals at very low bit rate is a hot area in the field of speech processing. We used stochastic inter-frame interpolators and vector quantization (VQ) as a new method for developing a high quality 1200 BPS speech vocoder. The objective and subjecgtive test results show that performance of the new vocoder is compairable with 4800 BPS standard vocoders (as CELP).
متن کاملUsing FFI Interpolator and VQ Quantization for Designing of High Quality 1200 BPS Speech Vocoder
Storaging or transmission of speech signals at very low bit rate is a hot area in the field of speech processing. We used stochastic inter-frame interpolators and vector quantization (VQ) as a new method for developing a high quality 1200 BPS speech vocoder. The objective and subjecgtive test results show that performance of the new vocoder is compairable with 4800 BPS standard vocoders (as CELP).
متن کاملSpeech Enhancement using Adaptive Data-Based Dictionary Learning
In this paper, a speech enhancement method based on sparse representation of data frames has been presented. Speech enhancement is one of the most applicable areas in different signal processing fields. The objective of a speech enhancement system is improvement of either intelligibility or quality of the speech signals. This process is carried out using the speech signal processing techniques ...
متن کامل