自己写的将二维小波分解后的系数提取正操作和逆操作，比如，一副图像进行一次小波分解后系数只是一个数列，不直观，提取之后将形成4个二维数组，分别含有低频系数和3个高频系数。-Write their own dimensional wavelet decomposition coefficients extraction positive operating and inverse operation, such as an image once after wavelet decomposition coefficient is just a series of non-intuitive, the extraction will form a two-dimensional array of four, respectively, containing low-frequency coefficients and the three high-frequency coefficients.