关键词: 混音, 电话会议, 自适应减谱法, 傅里叶变换, 功率谱

Abstract: Mixing treatment plays a pivotal role in Internet phone conference system. The core of mixing processing is how to resolve overflow and noise problems caused by the mixing. By analyzing the existing problems in mixing algorithm, an adaptive spectral method was proposed. Without overflowing, Fourier transform was applied to the speech signal. The noise power spectrum was removed from the noisy speech power spectrum, and then a more pure voice frequency spectrum was achieved. Fourier inverse transform was compatible with the mixing weights to make the sound quality clearer and more naturally smooth after mixing. It solves noise problems of mixing process and improves the quality of post-mixing to approximate the effect of real meeting. Therefore, it can be applied to multi-media conference system.

Key words: mixing, telephone conference, adaptive spectrum, Fourier transform, power spectrum