dwtmult1.m

来自「这是一个用matlab写的小波域HMM进行一维信号处理的程序」· M 代码 · 共 23 行

% dwtmult1.m
%
% Performs multiple levels of the discrete wavelet transform (using
% dwtlevel1).  Lines up stuff for "tree" structure
% Usage : w = dwtmult1(x, h0, h1, L)
%
% Written by : Justin Romberg
% Created : 5/1/2001

function w = dwtmult1(x, h0, h1, L)

N = length(x);
m0 = length(h0);
m1 = length(h1);
% delay to line up tree structure
z = floor((m0-m1)/4)+1;

w = x;
for ll = 1:L
  w(1:N*2^(-ll+1)) = dwtlevel1(w(1:N*2^(-ll+1)), h0, h1);
  w(1:N*2^(-ll)) = cshift(w(1:N*2^(-ll)),z,'l');
end