中文说明：应用背景过零率（ZCR）是另一个基本的声学特征，可以很容易计算。它等于给定帧内波形的过零数。ZCR具有以下特点：过清音和环境噪声通常比浊音，具有可观测的基本周期。很难区分清音环境噪声采用ZCR仅仅因为他们有相似的ZCR值。ZCR经常结合能量（或体积）的终点检测。特别是，ZCR是用于检测的开始和结束位置的清音。有人用过粗的基频估计，但它是非常不可靠，除非进一步细化程序进行后处理。为了避免直流偏置，通常我们需要在每一帧上进行平均的减法运算。这里是一个简单的例子，过如果我们要检测一个流音频信号的有意义的声音的活动，我们需要进行端点检测和语音检测。终点检测的最简单的方法是基于体积和ZCR。 ；关键技术 ；过零率 ；是符号沿着 变化率；信号，即，速率的信号从正变为负或背部。 ；此功能已被大量使用在 ；语音识别 ；和 ；音乐信息分类检索，被撞击的声音的一个重要特征。
English Description：
Application background Zero-crossing rate (ZCR) is another basic acoustic feature that can be computed easily. It is equal to the number of zero-crossing of the waveform within a given frame. ZCR has the following characteristics: ZCR of unvoiced sounds and environmental noise are usually larger than voiced sounds, which has observable fundamental periods. It is hard to distinguish unvoiced sounds from environmental noise by using ZCR alone since they have similar ZCR values. ZCR is often used in conjunction with energy (or volume) for end-point detection. In particular, ZCR is used for detecting the start and end positions of unvoiced sounds. Some people use ZCR for rough fundamental frequency estimation, but it is highly unreliabl