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Vector quantization of speech frames based on self-organizing maps
Flávio Olmos Simões1, Mário Uliani Neto, Jeremias Barbosa Machado
1Telecommunications Research Center (CPqD), Rod. Campinas-Mogi-Mirim (SP 340), km 118,5, Campinas, SP, 13086-902, Brazil. simoes@cpqd.com.br
Advances in Experimental Medicine and Biology
|December 19, 2009
Summary
This study introduces a novel speech compression method using unsupervised neural networks for vector quantization. The technique utilizes a self-organizing Kohonen map to generate a codebook, improving speech quality compared to existing algorithms.
Area of Science:
- Signal Processing
- Artificial Intelligence
- Machine Learning
Background:
- Speech compression is crucial for efficient data transmission and storage.
- Vector quantization (VQ) is a widely used technique for data compression.
- Traditional VQ methods often require complex codebook generation.
Purpose of the Study:
- To propose a novel speech compression technique leveraging unsupervised learning.
- To implement a vector quantizer using a neural network.
- To explore the use of a self-organizing Kohonen map for codebook generation.
Main Methods:
- Speech signal processing fundamentals are reviewed.
- Vector quantization principles are discussed.
- A 2-dimensional self-organizing Kohonen map is employed to create the VQ codebook.
- Neural network-based unsupervised learning is utilized for codebook generation.
Main Results:
- Simulation results provide insights into network topology, initialization, and training strategies.
- The impact of codebook size on compression performance is analyzed.
- Speech quality is evaluated based on the generated codebook.
Conclusions:
- The proposed neural network-based vector quantization offers an effective approach to speech compression.
- The self-organizing Kohonen map provides a viable method for generating efficient speech compression codebooks.
- The technique demonstrates competitive speech quality when compared to established compression algorithms.
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