[Learn one] Matlab GUI study notes Ⅰ

Matlab GUI Study Notes Ⅰ

1. Foreword

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• Is Matlab strictly a programming language? Someone once told me that he learned object-oriented programming through Matlab. I don't believe it, but this still does not prevent its powerful functions in special fields. Because of this 1-credit Matlab GUI design, some people expressed some emotions about the Previous Matlab Blog , so they wrote some Matlab GUI programming learning experience.
• Although the title is Matlab GUI Study Notes I, it can also be called Image Processing Technology Application Practice - Course Design 1 Guide North.
• The environment used in this article is the Chinese version of Matlab R2018a.

2. Task

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• Self-study Matlab GUI programming, design and implement an image space transformation system.
• Require:
  • Can perform translation, rotation, scaling, shearing, projection, affine, transformation and various compound transformations on images;
  • Can save various transformed results as image files;
  • Various transformations can be carried out in the form of buttons or menus;
  • During transformation, users can set simple transformation parameters by themselves.

3. Function

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3.1 Create

• In the command line window, enter and guideselect the new GUI tab Blank GUI (Default)
• The Chinese version of the Chinese version is relatively complete, and the controls corresponding to all options in the left toolbar have their Chinese names.
• Right click on the panel -> Inspector -> Name to modify the form title
• Mainly used AXES, BUTTON controls

3.2 File

The origin of all things.
Realize the effect:

3.2.1 Open picture

• uigetdir select file (folder)
• imread()read in image

• Code:

  [ReadImageFileName,ReadImagePathName,ReadImageFilterIndex] = uigetfile({'*.jpg;*.png;*.tif','ImageFile(*.jpg;*.png;*.tif)';...  
  '*.jpg','JPEGImageFile(*.jpg)';'*.*','AllFile(*.*)'},'ReadImage',...  
  'MultiSelect','off',...       
  'C:\Users\Public\Pictures\Sample Pictures');
   FirstImageFullPath = fullfile(ReadImagePathName,ReadImageFileName); 
  InputImage=imread(FirstImageFullPath);

3.2.2 Save picture

• uigetdir select file (folder)
• imwrite()save document

• Code:

  [SaveImagePathName] = uigetdir('C:\Users\Public\Pictures\Sample Pictures','请选择文件夹');
  filepath=fullfile(SaveImagePathName,'result.jpg');  
  imwrite(ResultImage,filepath,'jpg');

3.2.3 Display pictures

• axes()positioning display axes
• imshow()display image

• Code:

  axes(findobj('tag', 'axes1')); 
  InputImage=imread(FirstImageFullPath);
  imshow(InputImage);  

3.3 Transition

Realize the effect:

3.3.1 Panning

• imdilate()function to implement image translation

• Code:

  se=translate(strel(1),[100,100]);  
  ResultImage=imdilate(InputImage,se);

3.3.2 User Interaction

• inputdlg()Function to open a dialog to interact with the user
• Set parameters according to the returned value obtained
• The part that involves user interaction in the following functions is omitted.

• Code:

  defaulta={'100'};
  a=inputdlg('请输入x轴参数','',1,defaulta);

3.4 rotate

• Realize the effect:
  
• use imrotata()function
• Code :ResultImage = imrotate(InputImage,90);

3.5 Scale

• Realize the effect:
  
• use resize()function
• Code :ResultImage=imresize(InputImage,1.5);

3.6 Clipping

Personally think the hardest part.
The final effect:

3.6.1 Button Interaction

• get(hObject,'String');The return value is the title of the button
• set(hObject,'String','ChangeToTitle');change button title

• Use if statement nesting to judge the toggle button title:

  now = get(hObject,'String');
  if now == '剪切'
  set(hObject,'String','确定');
  else
  set(hObject,'String','剪切');
  end

3.6.2 Cut the image

• imrect()Create image selection using
  egimrect(handle, selection size);
• getPosition()get location
• imcrop()clip image

• Code:

  h=imrect(handles.axes1, [10 10 100 100]);  
  pos=getPosition(h);
  ResultImage=imcrop(InputImage, pos);

3.6.3 Other functions

• getAPI()get function handle
• addNewPositionCallback()add listener

• makeConstrainToRectFcn()listener event

  api = iptgetapi(h);  
  api.addNewPositionCallback(@(p) title(mat2str(p,3)));  %标题显示选区大小
  fcn = makeConstrainToRectFcn('imrect',get(gca,'XLim'),get(gca,'YLim'));  
  api.setPositionConstraintFcn(fcn);  %防止选区超出axes范围

3.7 Projection

Realize the effect:

3.7.1 Question Box Interaction

• questdlg(Title,Text,choice,...,DafaultChoice)Question box function
• Code :s = questdlg('请选择投影方式','参数','垂直','水平','垂直水平','垂直');

3.7.2 Projection

• See book.
• refer to

3.8 Affine & Transformation & ... & Postscript

No longer.