recoverback

代码说明：

  将一个小波结构的矩阵反排成小波包结构矩阵，根据最高的分解层次，将原图3*level+1块分开赋给矩阵以便单独操作，按从上到下，从左到右的顺序(Anti-matrix of a wavelet structure arranged in wavelet packet structure matrix, according to the highest level of decomposition, the original 3* level+1 separate assigned to the matrix in order to operate independently from top to bottom, left to right order)