A Modified Tunable – Q Wavelet Transform Approach for Tamil Speech Enhancement

ABSTRACT

In this paper, a new speech enhancement approach using the modified Tunable-Q Wavelet Transform (TQWT) for Tamil speaker recognition systems is proposed. Different forms of the existing wavelet transforms like continuous wavelet transform and discrete wavelet transform provide little ability to tune the Q factor and redundancy of the wavelet and have less reconstruction property. TQWT is fully discrete, has perfect reconstruction property and is modestly overcomplete. The Q-factor and redundancy can be easily tuned. Speech signals vary in both time and space. The entire speech signal is divided into different parts. Depending on the oscillatory contents of the speech signal, different Q factors are applied for each part instead of applying a single Q factor for the entire data. This gives more accuracy in decomposition. The proposed method is evaluated on several speakers and under various noise conditions including babble, street and exhibition noises. In order to tune the quality factor (Q) of the TQWT and to obtain good reconstruction property, speech enhancement has been conducted with varying values of Q. The reconstruction error, cost function, Signal to Noise Ratio(SNR) and Mean Opinion Score(MOS) show that the new approach highly improves the performance of speech enhancement based on the modified TQWT. Hardware implementation is also done using TMS320C6713 DSK and the results are similar to simulation.

KEYWORDS:

• Tamil
• Speech processing
• Speech enhancement
• Tunable-Q wavelet transform
• Q factor
• Redundancy
• Basis pursuit denoising

Additional information

Notes on contributors

J. Indra

J Indra is an associate professor in the Department of Electronics & Instrumentation Engineering at Kongu Engineering College. She received her BE degree in electrical & electronics engineering from Bharathiyar University, Tamilnadu, India, ME degree in VLSI design and PhD in information and communication engineering from Anna University, Chennai, Tamilnadu, India. She has 15 years of experience in the teaching field. She is a life member of ISTE. She has published about 18 papers in the reputed journals and in the national and international conferences. Her research interests include speech signal processing, VLSI and embedded systems.E-mail: [email protected]

R. Kiruba Shankar

R Kiruba Shankar received his bachelor's degree in instrumentation engineering from the Bharathidasan University, master's degree in control & instrumentation engineering from Anna University, Chennai and PhD in electrical engineering from Anna University, Chennai. He is certified LabVIEW associate developer (CLAD) issued by National Instruments, Texas, US He is holding 15+ year’s experience, including more than 12 years of academic experience, presently he is working as associate professor in the Department of Mechatronics Engineering at Kongu Engineering College, one of the premier institutions in Tamilnadu. His research areas of interest include control system & instrumentation, internet-based control system, industrial automation,virtual instrumentation, process control and soft computing.E-mail: [email protected]

N. Kasthuri

N Kasthuri is professor in the Department of Electronics and Communication Engineering, Kongu Engineering College, India. She received her BE degree in electronics and communication engineering from A C Tech Karaikudi and ME degree in applied electronics from the Bharathiyar University, Tamilnadu, India. She obtained her doctoral degree in information and communication engineering from Anna University, Chennai, Tamilnadu, India. She has two decades of teaching experience. She has published about 52 papers in the reputed journals and in the national and international conferences. Her research interests cover signal processing, speech signal processing and embedded systems. She received research grants from various funding agencies. She is a Life Member of ISTE.E-mail: [email protected]

S. Geetha Manjuri

S Geetha Manjuri completed her BE degree in electronics and communication engineering and ME degree in applied electronics from Anna University, Chennai.E-mail: [email protected]