روش تفريق طيفی چندباندی اصلاح شده برای بهبود صحبت
محورهای موضوعی : مهندسی برق و کامپیوترمهدی بکرانی 1 , هادی صدوقی یزدی 2
1 - دانشگاه تربیت مدرس
2 - دانشگاه تربیت معلم سبزوار
کلید واژه: تفريق طيفی چندبانديبهبود صحبتنويز غيرايستانفاکتور فوقتفريقنويز موزيکال,
چکیده مقاله :
در اين مقاله يک روش اصلاح شدة تفريق طيفی چندباندی برای حذف نويز از سيگنال صحبت ارائه شده است. در اين روش با تخمين آمارگان نويز غيرايستان، تخمينی از SNR برای سيگنال صحبت بدست مي‌آيد که در ميانگين‌گيری وفقی از قابهای سيگنال صحبت بکار گرفته مي‌شود. همچنين با استفاده از آن يک فاکتور فوق‌تفريق بدست مي‌آيد که سبب کاهش قابل توجه نويز موزيکال مي‌شود. تنظيم پارامترهای الگوريتم نهايی بر اساس SNR بدست آمده انجام مي‌شود؛ بطوري‌که الگوريتم نهايی دارای حداقل نويز موزيكال و اعوجاج در سيگنال صحبت است. نتايج حاصل از معيارهای ايتاکورا-سايتو، SNR سراسری و SNR قطعه‌ای نشان مي‌دهد که الگوريتم پيشنهادی دارای سيگنال خروجی با کيفيت بهتری نسبت به دو الگوريتم تفريق طيفی چندباندی و نوع بهبوديافته آن مي‌باشد.
In this paper, a modified multi band spectral subtraction is proposed for speech denoising. In this method by estimating the non-stationary noise statistics an estimate of the SNR for the speech signal is obtained which is used in the adaptive averaging of the speech signal frames. In addition, by employing such estimate an over-subtraction factor can be obtained which substantially reduces the musical noise. The adjustment of the final algorithm parameters is accomplished based on the obtained SNR, such that the final algorithm has a minimum musical noise and distortion in the speech signal. The obtained results from the Itakura-Saito, global SNR and segmental SNR show that the proposed algorithm has an output signal with a superior quality compared to the multi-band spectral subtraction algorithm and its modified version.
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