A fractal based voice activity detector for Internet telephone

The fractal dimension is useful in discriminating different textures of images. Also, the distinction between the 'texture' of speech signals and that of noise should exist because speech signals are regular 'man-made' processes and noises are random 'natural' processes. Through experiments, we found that the fractal dimension of speech signals is distinctly different from that of noise. Thus, a fractal based voice activity detector (VAD) is proposed. The experimental results show that the proposed VAD outperforms two traditional approaches based on energy and zero-crossing rate at low SNR. Applied to the Internet telephone developed by us, this VAD improves the quality of service.