numvanish.m

来自「基于MATLAB的图像压缩 能处理10:1的压缩功能 直接就能使用」· M 代码 · 共 9 行

function N = numvanish(g)
% Determine the number of vanishing moments from highpass filter g(z)

for N = 0:length(g)-1  % Count the number of roots at z = 1
   [g,r] = deconv(g,[1,-1]);
   if norm(r,inf) > 1e-7, break; end
end
return;