一、简介
基于matlab虹膜图像高斯滤波、低通滤波、巴特沃斯滤波
二、源代码
function varargout = frequencydem(varargin)
% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name', mfilename, ...
'gui_Singleton', gui_Singleton, ...
'gui_OpeningFcn', @frequencydem_OpeningFcn, ...
'gui_OutputFcn', @frequencydem_OutputFcn, ...
'gui_LayoutFcn', [] , ...
'gui_Callback', []);
if nargin & isstr(varargin{1})
gui_State.gui_Callback = str2func(varargin{1});
end
if nargout
[varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
gui_mainfcn(gui_State, varargin{:});
end
% End initialization code - DO NOT EDIT
%----------------------------------------------------------
% --- Executes just before frequencydem is made visible.
function frequencydem_OpeningFcn(hObject, eventdata, handles, varargin)
handles.output = hObject;
% Update handles structure
guidata(hObject, handles);
movegui(hObject,'onscreen')% To display application onscreen
movegui(hObject,'center') % To display application in the center of screen
image_file = get(handles.nameEdit,'String');
im_original=image_read(char(image_file));
set(handles.Or_image,'HandleVisibility','OFF')
set(handles.filtered_image,'HandleVisibility','OFF');
set(handles.difference_image,'HandleVisibility','OFF');
set(handles.filt3D,'HandleVisibility','OFF');
set(handles.filt2D,'HandleVisibility','OFF');
set(handles.Or_image,'HandleVisibility','ON')
axes(handles.Or_image);
imagesc(im_original);
colormap(gray(256));
axis equal;
axis tight;
axis off;
set(handles.Or_image,'HandleVisibility','OFF')
set(handles.Or_image,'XTickLabel',' ','YTickLabel',' ')
%----------------------------------------------------------
% --- Outputs from this function are returned to the command line.
function varargout = frequencydem_OutputFcn(hObject, eventdata, handles)
varargout{1} = handles.output;
%----------------------------------------------------------
% --- Executes during object creation, after setting all properties.
function image_selection_CreateFcn(hObject, eventdata, handles)
if ispc
set(hObject,'BackgroundColor','white');
else
set(hObject,'BackgroundColor',get(0,'defaultUicontrolBackgroundColor'));
end
%----------------------------------------------------------
% Executes on button press in apply_button.
function apply_button_Callback(hObject, eventdata, handles)
image_file = get(handles.nameEdit,'String'); % to read the image filename selected
im_original=image_read(char(image_file)); % filename
% set(handles.Or_image,'HandleVisibility','ON') % to make plot 1 visible for original image plot
% image(im_original);
% colormap(gray(256));
% axis image;
% axis off;
% set(handles.filtered_image,'HandleVisibility','OFF') % to make plot 2 unvisible to the original image plot
set(handles.Or_image,'XTickLabel',' ','YTickLabel',' ') % to get rid of tick labels
method_number = get(handles.method_selection,'Value'); % selected method
t = get(handles.cutoffEdit,'String');
F_cut = str2num (t);
if F_cut <= 0
msgbox ('Please input meaningful cut off frequency');
return
end;
% For gaussian blur and USM-Filter method
switch method_number
case { 1 } %Ideal Filter
[im_filtered, H] = ideal_low(im_original, F_cut);
case { 2 }
[im_filtered, H] = ideal_high(im_original, F_cut);
case { 3 }
[im_filtered, H] = gaussian_low(im_original,F_cut);
case { 4 }
[im_filtered, H]= gaussian_high(im_original, F_cut);
case { 5 }
t = get(handles.butflyEdit,'String');
n = str2num (t);
if t <= 0
msgbox('Invalid order number!');
return;
end;
[im_filtered, H] = butterworth_low(im_original, F_cut,n);
case { 6 }
t = get(handles.butflyEdit,'String');
n = str2num (t);
if t <= 0
msgbox('Invalid order number!');
return;
end;
[im_filtered, H] = butterworth_high(im_original, F_cut,n);
end;
set(handles.Or_image,'HandleVisibility','ON')
axes(handles.Or_image);
imagesc(im_original);
colormap(gray(256));
axis equal;
axis tight;
axis off;
set(handles.Or_image,'HandleVisibility','OFF')
set(handles.filtered_image,'HandleVisibility','ON') ; % to make plot 2 visible to the filtered image plot
axes(handles.filtered_image);
imagesc(im_filtered) % to plot filtered image
colormap(gray(256));
axis equal;
axis tight;
axis off;
set(handles.filtered_image,'HandleVisibility','OFF')
set(handles.difference_image,'HandleVisibility','ON');
axes(handles.difference_image);
dif_image = im_filtered- im_original;
imagesc(dif_image);
colormap(gray(256));
axis equal;
axis tight;
axis off;
set(handles.difference_image,'HandleVisibility','OFF')
set(handles.filt2D,'HandleVisibility','ON');
axes(handles.filt2D);
imagesc(H);
colormap(gray(256));
axis equal;
axis tight;
axis off;
set(handles.filt2D,'HandleVisibility','OFF');
set(handles.filt3D,'HandleVisibility','ON');
axes(handles.filt3D);
[co,ro]=size(H);
surfl(H);
set(handles.filt3D,'HandleVisibility','OFF');
%----------------------------------------------------------
% --- Executes on button press in close_button.
function close_button_Callback(hObject, eventdata, handles)
close all; % to close GUI
%----------------------------------------------------------
% --- Executes during object creation, after setting all properties.
function method_selection_CreateFcn(hObject, eventdata, handles)
if ispc
set(hObject,'BackgroundColor','white');
else
set(hObject,'BackgroundColor',get(0,'defaultUicontrolBackgroundColor'));
end
% --- Executes during object creation, after setting all properties.
function nameEdit_CreateFcn(hObject, eventdata, handles)
% hObject handle to nameEdit
% eventdata reserved - to be defined in a future version of MATLAB
% handles empty - handles not created until after all CreateFcns called
% Hint: edit controls usually have a white background on Windows.
% See ISPC and COMPUTER.
if ispc
set(hObject,'BackgroundColor','white');
else
set(hObject,'BackgroundColor',get(0,'defaultUicontrolBackgroundColor'));
end
%Read all kinds of image files
function im_original=image_read(image_file)
lg=length(image_file);
if strcmpi(image_file(lg-2:lg),'mat') | strcmpi(image_file(lg-2:lg),'dat')
im_original=load(image_file);
else
im_original=imread(char(image_file));
end;
im_original = double(im_original);
t=size(im_original,3);
if t==3
imt=floor((im(:,:,1)+im(:,:,2)+im(:,:,3))/3);
clear im_original;
im_original=imt;
clear imt;
end;
t=size(im_original,3);
if t~=1
display('Error in opening the image file!');
end;
% butterworth high pass filter
function [out, H] = butterworth_high (im,fc,n)
[co,ro] = size(im);
cx = round(co/2); % find the center of the image
cy = round (ro/2);
imf=fftshift(fft2(im));
H=zeros(co,ro);
for i = 1 : co
for j =1 : ro
d = (i-cx).^2 + (j-cy).^ 2;
if d ~= 0
H(i,j) = 1/(1+((fc*fc/d).^(2*n)));
end;
end;
end;
outf = imf .* H;
out = abs(ifft2(outf));
% butterworth low pass filter
function [out, H] = butterworth_low (im,fc,n)
[co,ro] = size(im);
cx = round(co/2); % find the center of the image
cy = round (ro/2);
imf=fftshift(fft2(im));
H=zeros(co,ro);
for i = 1 : co
for j =1 : ro
d = (i-cx).^2 + (j-cy).^ 2;
H(i,j) = 1/(1+((d/fc/fc).^(2*n)));
end;
end;
outf = imf .* H;
out = abs(ifft2(outf));
%Gaussian high pass filter
function [out, H] = gaussian_high(im, fc)
imf = fftshift(fft2(im));
[co,ro]=size(im);
H = gaussian_filter(co,ro, fc);
H = 1-H;
out = zeros(co,ro);
outf= imf.*H;
out=abs(ifft2(outf));
%Gaussian lowpass filter
function [out, H] = gaussian_low(im, fc)
imf = fftshift(fft2(im));
[co,ro]=size(im);
out = zeros(co,ro);
H = gaussian_filter(co,ro, fc);
outf= imf.*H;
out=abs(ifft2(outf));
% gaussian filter
function H = gaussian_filter(co,ro, fc)
cx = round(co/2); % find the center of the image
cy = round (ro/2);
H = zeros(co,ro);
for i = 1 : co
for j = 1 : ro
d = (i-cx).^2 + (j-cy).^2;
H(i,j) = exp(-d/2/fc/fc);
end;
end;
三、运行结果
四、备注
版本：2014a 完整代码或代写加1564658423
