【图像分割】基于类间方差阈值图像分割与腐蚀膨胀matlab源码
一、简介
1 概述
在计算机视觉和图像处理领域，最大类间方差法（otsu）又叫做大津法，是1979年由日本学者大津提出的，是一种自适应阈值分割方法，减少灰阶图像等级成为一个二值图像。该算法假定图像分为两类（符合双峰直方图分布，两类分别称为前景/目标像素和背景像素），然后计算出一个最优的阈值将将此图像分为两类使得其类间方差最大。Otsu是费舍尔离散判断分析的一维表现形式。
2 方法
二、源代码
function varargout = experiment3(varargin)
% EXPERIMENT3 MATLAB code for experiment3.fig
% EXPERIMENT3, by itself, creates a new EXPERIMENT3 or raises the existing
% singleton*.
%
% H = EXPERIMENT3 returns the handle to a new EXPERIMENT3 or the handle to
% the existing singleton*.
%
% EXPERIMENT3('CALLBACK',hObject,eventData,handles,...) calls the local
% function named CALLBACK in EXPERIMENT3.M with the given input arguments.
%
% EXPERIMENT3('Property','Value',...) creates a new EXPERIMENT3 or raises the
% existing singleton*. Starting from the left, property value pairs are
% applied to the GUI before experiment3_OpeningFcn gets called. An
% unrecognized property name or invalid value makes property application
% stop. All inputs are passed to experiment3_OpeningFcn via varargin.
%
% *See GUI Options on GUIDE's Tools menu. Choose "GUI allows only one
% instance to run (singleton)".
%
% See also: GUIDE, GUIDATA, GUIHANDLES
% Edit the above text to modify the response to help experiment3
% Last Modified by GUIDE v2.5 31-May-2018 16:55:57
% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name', mfilename, ...
'gui_Singleton', gui_Singleton, ...
'gui_OpeningFcn', @experiment3_OpeningFcn, ...
'gui_OutputFcn', @experiment3_OutputFcn, ...
'gui_LayoutFcn', [] , ...
'gui_Callback', []);
if nargin && ischar(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 experiment3 is made visible.
function experiment3_OpeningFcn(hObject, eventdata, handles, varargin)
% This function has no output args, see OutputFcn.
% hObject handle to figure
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
% varargin command line arguments to experiment3 (see VARARGIN)
% Choose default command line output for experiment3
handles.output = hObject;
% Update handles structure
guidata(hObject, handles);
% UIWAIT makes experiment3 wait for user response (see UIRESUME)
% uiwait(handles.figure1);
% --- Outputs from this function are returned to the command line.
function varargout = experiment3_OutputFcn(hObject, eventdata, handles)
% varargout cell array for returning output args (see VARARGOUT);
% hObject handle to figure
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
% Get default command line output from handles structure
varargout{1} = handles.output;
function edit1_Callback(hObject, eventdata, handles)
% hObject handle to edit1 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
% Hints: get(hObject,'String') returns contents of edit1 as text
% str2double(get(hObject,'String')) returns contents of edit1 as a double
% --- Executes during object creation, after setting all properties.
function edit1_CreateFcn(hObject, eventdata, handles)
% hObject handle to edit1 (see GCBO)
% 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 && isequal(get(hObject,'BackgroundColor'), get(0,'defaultUicontrolBackgroundColor'))
set(hObject,'BackgroundColor','white');
end
% --- Executes on button press in pushbutton1.
function pushbutton1_Callback(hObject, eventdata, handles)
% hObject handle to pushbutton1 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
shiyan3 = rgb2gray(imread('shiyan3.bmp'));
size_filter_m = str2double(get(handles.edit1,'string'));
size_filter_n = str2double(get(handles.edit2,'string'));
if isnan(size_filter_m)
size_filter_m = 3;
end
if isnan(size_filter_n)
size_filter_n = 3;
end
shiyan3_filter = medfilt2(shiyan3,[size_filter_m,size_filter_n]); %中值滤波
threshold = graythresh(shiyan3_filter); %用最大类间方差法找到阈值
shiyan3_seg = im2bw(shiyan3_filter,threshold); %阈值分割
axes(handles.axes1);
imshow(shiyan3);
title('原图');
axes(handles.axes2);
imshow(shiyan3_filter);
title('中值滤波');
axes(handles.axes3);
imshow(shiyan3_seg);
title('类间方差阈值分割');
% --- Executes on button press in pushbutton2.
function pushbutton2_Callback(hObject, eventdata, handles)
% hObject handle to pushbutton2 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
shiyan3 = rgb2gray(imread('shiyan3.bmp'));
size_filter_m = str2double(get(handles.edit1,'string'));
size_filter_n = str2double(get(handles.edit2,'string'));
if isnan(size_filter_m)
size_filter_m = 3;
end
if isnan(size_filter_n)
size_filter_n = 3;
end
shiyan3_filter = medfilt2(shiyan3,[size_filter_m,size_filter_n]); %中值滤波
threshold = graythresh(shiyan3_filter); %用最大类间方差法找到阈值
shiyan3_seg = im2bw(shiyan3_filter,threshold); %阈值分割
axes(handles.axes1);
imshow(shiyan3);
title('原图');
axes(handles.axes2);
imshow(shiyan3_filter);
title('中值滤波');
axes(handles.axes3);
imshow(shiyan3_seg);
title('类间方差阈值分割');
se = strel('disk',1); %结构元素
shiyan3_erode1 = imerode(shiyan3_seg,se); %腐蚀
axes(handles.axes4);
imshow(shiyan3_erode1);
title('腐蚀: r=1');
se = strel('diamond',8);
shiyan3_erode2 = imerode(shiyan3_seg,se);
axes(handles.axes5);
imshow(shiyan3_erode2);
title('腐蚀: r=8');
se = strel('disk',8);
shiyan3_erode3 = imerode(shiyan3_seg,se);
axes(handles.axes6);
imshow(shiyan3_erode3);
title('腐蚀: r=8');
% --- Executes on button press in pushbutton3.
function pushbutton3_Callback(hObject, eventdata, handles)
% hObject handle to pushbutton3 (see GCBO)
% eventdata reserved - to be defined in a future version of MATLAB
% handles structure with handles and user data (see GUIDATA)
shiyan3 = rgb2gray(imread('shiyan3.bmp'));
size_filter_m = str2double(get(handles.edit1,'string'));
size_filter_n = str2double(get(handles.edit2,'string'));
if isnan(size_filter_m)
size_filter_m = 3;
end
if isnan(size_filter_n)
size_filter_n = 3;
end
三、运行结果
