SNR-dependent flooring and noise overestimation for joint application of spectral subtraction and model combination
نویسندگان
چکیده
We present an approach to joint application of spectral subtraction (SPS) and model combination (PMC) for speech recognition in noisy environments. Contrary to previous solutions e.g. [2] distortion introduced by SPS is not modeled in PMC. Instead we ensure compatibility of the two methods by adapting parameters of SPS (spectral floor and overestimation factor) according to the present signalto-noise-ratio (SNR). The scheme leaves the model combination process unchanged which simplifies parameter estimation and reduces computation time. Experiments show significant improvements when using PMC with modified SPS instead of standard SPS.
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