数字图像处理课程设计

数字图像处理课程设计

姓名：

班级：13信息卓越

学号：4

课程名称：对数灰度变换

指导老师：

（一）设计内容的目标和意义

1.1设计目标

1、MATLAB界面编程简介；

2、图像的对数灰度变换简介；

3、采用MATLAB Guide设计界面，设计实现下列功能的按钮：点击下一步可以实现图像灰度变换，可以读取相应的代码。

4、对数灰度变换的算法设计与实现；

1.2设计意义

本课题主要是通过MATLAB界面编程实现图像的对数灰度变换，以此来实现图像增强，使图像更适合于进一步的分析和对它内容的提取。实现界面编程可以更方便的对图片进行操作，例如可以打开一张图片，可以使图像处理结果更直观，对比更明显，更利于进行观察，同时可以实现保存处理后的图片，这样，图像的操作更简洁、直接。

（二）设计原理

2.1对数灰度变换原理

一些图片的像素过于集中于中间灰度部分，而其他部分的像素数很少，可以压缩像素数小的部分，扩展像素数集中的部分。如果只想了解图像的某一部分，那么可以压缩其它部分，对关注的部分进行变换。当用对数函数作为图像的映射函数时,可实现图像灰度的非线性变换，对数扩展拉伸低亮度去，压缩高亮度区。

2.2对数灰度变换公式

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=

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C

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(g y

式中：C为尺度比例常数；1+|f(x,y)|是为了避免对零求对数

2.3对数灰度变换的基本代码

源代码如下：

Clear;

A=imread(‘1.jpg’); %读入图像

B=log(A+1); %灰度调整

Imwrite(B,’’) ; %图像保存

Subplot(2,2,1); imshow(A); %显示调整后图像

Subplot(2,2,2); imhist(A);

Subplot(2,2,3); imshow(B);

Subplot(2,2,4); imhist(B);

2.4设计流程

（1）在MATLAB命令窗口中输入“guide”,进入GUI窗口，选择

Create New GUI,选择Black GUI。

（2）在界面中添加1个axes,用于显示图片,并设置每个axes的Tag值。

（3）添加3个Panel，分别为对数变换和 Commandwindow。对数变换中添加一个radiobutton和text， Commandwindow中添加一个edit用于显示代码，另一个中再添加4个button，分别为开始、上一步、下一步和退出，并为每个button 设置Tag值。

图2.1进入GUI窗口图

图2.2在界面中添加1个axes

图2.3添加一个对数变换的uipanel 图2.4添加一个用于显示程uipanel

图2.5添加四个按钮

图2.6完整的GUI界面图

(三)设计结果

3.1文字说明

1.原始图片的像素为1000pi*1000pi（如图3.1）；

2.经过程序，把原始图片数据转换为双精度，经过傅里叶变换得到原始图像的傅里叶频谱（如图

3.2）；

3.点击GUI界面中的“开始”按钮，进行第一次对数灰度变换，此时的C值为0.3，再依次点击下一步，C值依次变为0.3,0.6,1.0,1.6,2.2，所得到的结果图如图3.3,3.4,3.5,3.6,3.7所示。

图3.1.原图图3.2.原图的傅里叶频谱图

当x=0:1:255，y=0.3*log(1+x)时，对图像进行对数变换，结果如图3.3所示：

图3.3 对数变换结果

当x=0:1:255，y=0.6*log(1+x)时，对图像进行对数变换，结果如图3.4所示：

图3.4 对数变换结果

当x=0:1:255，y=1.0*log(1+x)时，对图像进行对数变换，结果如图3.5所示：

当x=0:1:255，y=1.6*log(1+x)时，对

图像进行对数变换，结果如图3.6所示：图3.5 对数变换结果图3.6 对数变换结果

当x=0:1:255，y=2.2*log(1+x)时，对图像进行对数变换，结果如图3.7所示：

图3.7 对数变换结果

3.2分析和评价处理结果

1.经过对数灰度变换扩展了低值灰度，压缩了高值灰度，这样可以使低值灰度的图像细节更容易看清，从而达到增强的效果。

2.将原始图像经过傅里叶变换后得到相对应的傅里叶频谱图，对所得到的傅里叶频谱有选择的对某一灰度值范围进行扩展，其他范围的灰度值有可能被压缩。

附录：

function varargout = zhishu1(varargin)

% ZHISHU1 MA TLAB code for zhishu1.fig

% ZHISHU1, by itself, creates a new ZHISHU1 or raises the existing

% singleton*.

%

% H = ZHISHU1 returns the handle to a new ZHISHU1 or the handle to

% the existing singleton*.

%

% ZHISHU1('CALLBACK',hObject,eventData,handles,...) calls the local

% function named CALLBACK in ZHISHU1.M with the given input arguments. %

% ZHISHU1('Property','Value',...) creates a new ZHISHU1 or raises the

% existing singleton*. Starting from the left, property value pairs are

% applied to the GUI before zhishu1_OpeningFcn gets called. An

% unrecognized property name or invalid value makes property application

% stop. All inputs are passed to zhishu1_OpeningFcn via varargin.

%

% *See GUI Options on GUIDE's Tools menu. Choose "GUI allows only one % instance to run (singleton)".

%

% See also: GUIDE, GUIDA TA, GUIHANDLES

% Edit the above text to modify the response to help zhishu1

% Last Modified by GUIDE v2.5 14-Dec-2016 15:42:59

% Begin initialization code - DO NOT EDIT

gui_Singleton = 1;

gui_State = struct('gui_Name', mfilename, ...

'gui_Singleton', gui_Singleton, ...

'gui_OpeningFcn', @zhishu1_OpeningFcn, ...

'gui_OutputFcn', @zhishu1_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{:});

gui_mainfcn(gui_State, varargin{:});

end

% End initialization code - DO NOT EDIT

% --- Executes just before zhishu1 is made visible.

function zhishu1_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 zhishu1 (see V ARARGIN)

% Choose default command line output for zhishu1

handles.output = hObject;

global photo photo1 photo2 photo3

global zhi1 zhi2 %zhi1是C,zhi2是r

global curValue %当前值

global valueArray %值数组

global reStart %重置

zhi1=1.0;zhi2=1.0;

curValue=0;

valueArray=[0.3,0.6,1,1.6,2.2];

reStart=0;

% % % set(handles.radiobutton7,'enable','off');%打开默认选择对数，将指数部分默认隐藏% % % set(handles.radiobutton8,'enable','off');

% % % set(handles.radiobutton9,'enable','off');

% % % set(handles.radiobutton15,'enable','off');

% % % set(handles.radiobutton16,'enable','off');

set(handles.back,'enable','off');

set(handles.next,'enable','off');

set(handles.start,'enable','on');

warning off;

fname='1.jpg'; %插入图片

photo=imread('1.jpg'); %读取图片

photo=im2double(photo); %将图像转变为双精度

photo1=fft2(photo); %对图像进行二维的FFT变换

photo1=fftshift(photo1); %对photo1转化我频谱图

axes(handles.axes1);

imshow(abs(photo1)); %显示图像

% Update handles structure

guidata(hObject, handles);

% UIWAIT makes zhishu1 wait for user response (see UIRESUME)

% uiwait(handles.figure1);

% --- Outputs from this function are returned to the command line.

function varargout = zhishu1_OutputFcn(hObject, eventdata, handles)

% varargout cell array for returning output args (see V ARARGOUT);

% 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;

% --- Executes on button press in start.

function start_Callback(hObject, eventdata, handles) %开始按钮的作用global photo1 photo3 %设置全局变量

global zhi1 zhi2

global reStart

global curValue

if reStart==0

set(handles.back,'enable','off'); %返回按钮关闭

set(handles.next,'enable','on'); %下一步按钮开启

reStart=1;

return;

end

if reStart==1

curValue = 0;

set(handles.back,'enable','off');

set(handles.next,'enable','on');

set(handles.start,'enable','on');

set(handles.daima,'string','please input codes');

if get(handles.radiobutton10,'value')==1

photo=imread('1.jpg'); %读取图片

photo=im2double(photo); %将图像进行双精度变换

photo1=fft2(photo); %将图像进行傅里叶变换

photo1=fftshift(photo1); %图像变成低频

axes(handles.axes1); %将上面的坐标轴做为当前坐标轴,在其上做图

imshow(abs(photo1)); %显示变换后的图片

%set(handles.edit2,'enable','off');

end

end

% hObject handle to start (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB

% handles structure with handles and user data (see GUIDATA)

% --- Executes on button press in back.

function back_Callback(hObject, eventdata, handles) %打开back这个菜单

global photo1 photo3 %设置全局变量

global zhi1 zhi2

global curValue

global valueArray

backIndex = 0;

for i=1:length(valueArray)

if valueArray(i) < curV alue

backIndex = i;

end

end

if backIndex == 0

return;

end

curValue = valueArray(backIndex);

set(handles.back,'enable','on');

set(handles.next,'enable','on');

if backIndex == 1

set(handles.back,'enable','off');

end

if backIndex == length(valueArray)

set(handles.next,'enable','off');

end

if get(handles.radiobutton10,'value')==1%预处理

val=1;

elseif get(handles.radiobutton11,'value')==1

val=2;

end

switch val

case 1

zhi1=curValue;

x=0:1:255;

y=zhi1*log(1+x);

dui_photo=im2double(photo1); %将图像经过双精度变换

dui_photo=zhi1*log(1+dui_photo); %经过公式进行变换

axes(handles.axes1);

imshow(dui_photo); %显示图像

num=sprintf('%0.1f',zhi1);

st='%显示代码：';

s1=['%读入一幅图像

',char(10),'x=0:1:255;',char(10),'y=',num,'*log(1+x);',char(10),'dui_photo=im2double(photo1);',ch ar(10),'dui_photo=',num,'*log(1+dui_photo);',char(10),'axes(handles.axes1);',char(10),'imshow(dui _photo);']; %读入图像经过对应的变换

set(handles.daima,'string',s1);

%set(handles.edit1,'string',zhi1);

end

% % set(handles.start,'enable','on');

% % set(handles.back,'enable','off');

% % set(handles.next,'enable','on');

% hObject handle to back (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB

% handles structure with handles and user data (see GUIDATA)

% --- Executes on button press in exit.

function exit_Callback(hObject, eventdata, handles)

clc;

clear; %清空

s1=['注意']; %弹出对话框，选择是否离开

s2=['确定离开吗？'];

button= questdlg(s2,s1);

switch button %单击Yes会关闭

case'Yes'

close;

end

% hObject handle to exit (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB

% handles structure with handles and user data (see GUIDATA)

% function daima_Callback(hObject, eventdata, handles)

% if runcode==1

% z=get(handles.daima,'String');

% z=char(z);

% try

% for k=1:size(z,1)

% eval(z(k,:));

% end

% catch

% set(handles.daima,'string','please input codes');

% helpdlg('请输入代码！','提示');

% end

% end

% runcode=1;

% hObject handle to daima (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB

% handles structure with handles and user data (see GUIDA TA)

% Hints: get(hObject,'String') returns contents of daima as text

% str2double(get(hObject,'String')) returns contents of daima as a double

% --- Executes during object creation, after setting all properties.

function daima_CreateFcn(hObject, eventdata, handles)

% hObject handle to daima (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

function next_Callback(hObject, eventdata, handles) %对next设置全局变量

global photo1 photo3

global zhi1 zhi2

global curValue

global valueArray

nextIndex = 0;

for i=1:length(valueArray)

if curValue < valueArray(i)

curValue = valueArray(i);

nextIndex = i;

break;

end

end

if nextIndex == 0

return;

end

set(handles.back,'enable','on');

set(handles.next,'enable','on');

if nextIndex == 1

set(handles.back,'enable','off');

end

if nextIndex == length(valueArray)

set(handles.next,'enable','off');

end

if get(handles.radiobutton10,'value')==1%预处理

val=1;

elseif get(handles.radiobutton11,'value')==1

val=2;

end

switch val

case 1

zhi1=curValue;

x=0:1:255;

y=zhi1*log(1+x);

dui_photo=im2double(photo1);

dui_photo=zhi1*log(1+dui_photo);

axes(handles.axes1);

imshow(dui_photo);

num=sprintf('%0.1f',zhi1);

st='%显示代码：';

s1=['%读入一幅图像

',char(10),'x=0:1:255;',char(10),'y=',num,'*log(1+x);',char(10),'dui_photo=im2double(photo1);',ch ar(10),'dui_photo=',num,'*log(1+dui_photo);',char(10),'axes(handles.axes1);',char(10),'imshow(dui _photo);'];

set(handles.daima,'string',s1);

%set(handles.edit1,'string',zhi1);

end

% % set(handles.next,'enable','off');

% % runcode=1;

% % if runcode==1

% % z=get(handles.daima,'String');

% % z=char(z);

% % try

% % for k=1:size(z,1)

% % eval(z(k,:));

% % end

% % catch

% % set(handles.daima,'string','please input codes');

% % helpdlg('请输入代码！','提示');

% % end

% % end

% % runcode=1;

% hObject handle to next (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB

% handles structure with handles and user data (see GUIDA TA)

function edit2_Callback(hObject, eventdata, handles)

global val2

global zhi2

val2=str2double(get(handles.edit2,'String'));

if ~isempty(val1)&&(val1>=1&val1<=10)

set(handles.daima,'value',val1);

else

helpdlg('check your number in 0 to 10','error');

end

% hObject handle to edit2 (see GCBO)

% eventdata reserved - to be defined in a future version of MATLAB

% handles structure with handles and user data (see GUIDA TA)

% Hints: get(hObject,'String') returns contents of edit2 as text

% str2double(get(hObject,'String')) returns contents of edit2 as a double

function daima_Callback(hObject, eventdata, handles)

% hObject handle to daima (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 daima as text

% str2double(get(hObject,'String')) returns contents of daima as a double

global photo1 photo3

global zhi1 zhi2

z=get(handles.daima,'String');

z=char(z);

try

for k=1:size(z,1)

eval(z(k,:));

end

catch

set(handles.daima,'string','please input codes');

helpdlg('请输入代码！','提示');

end