说明：  实现二维小波变换此示意程序用DWT实现二维小波变换此示意程序用DWT实现二维小波变换此示意程序用DWT实现二维小波变换
(Dimensional wavelet transform two-dimensional wavelet transform this schematic with DWT dimensional wavelet transform schematic program with this schematic program with a two-dimensional wavelet transform DWT DWT)