DPCM,由于语音信号的相邻抽样点之间有一定的幅度关联性，所以，可根据以前时刻的样值来预测现时刻的样值，只要传预测值和实际值之差，而不需要每个样值都传输。这种方法就是预测编码。-DPCM, as a result of voice signals between adjacent sampling rate of a certain relevance, we can kind of time based on previous values to predict the kind of val