disp_hhs.m

主要是希尔伯特——黄HHT中的EMD分解过程的工具箱

function disp_hhs(im,t,inf)

% DISP_HHS(im,t,inf)
% displays in a new figure the spectrum contained in matrix "im"
% (amplitudes in log).
%
% inputs : - im : image matrix (e.g., output of "toimage")
%          - t (optional) : time instants (e.g., output of "toimage") 
%          - inf (optional) : -dynamic range in dB (wrt max)
%            default : inf = -20
%
% utilisation : disp_hhs(im) ; disp_hhs(im,t) ; disp_hhs(im,inf) 
%              disp_hhs(im,t,inf)

figure
% colormap(bone)
% colormap(1-colormap);

if nargin==1
%   inf=-20;
inf=-200;   %改成200，以增加图象的对比度
  t = 1:size(im,2);

end

if nargin == 2
  if length(t) == 1
    inf = t;
    t = 1:size(im,2);
  else
    inf = -20;
  end
end

if inf >= 0
  error('inf doit etre < 0')
end

M=max(max(im));

im =log10(im/M+1e-300);

% maxim=max(max(im));
% minim=min(min(im));
% [ii,iii]=size(im);
% for i=1:ii
%     for j=1:iii
%         if im(i,j)/(maxim+1e-300)<=0.04
%             im(i,j)=minim;
%         end
%     end
% end

inf=inf;


% imagesc(t,fliplr((1:size(im,1))/(2*size(im,1))),im,[inf,0]);
imagesc(t,fliplr((1:size(im,1))/(2*size(im,1))),im,[-20,-1]);
set(gca,'YDir','normal')
xlabel(['time'])
ylabel(['normalized frequency'])
title('Hilbert-Huang spectrum')