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imshow inhibits gui from running minimized

Asked by Max

Max (view profile)

on 21 Mar 2014
Latest activity Commented on by Sean de Wolski

Sean de Wolski (view profile)

on 9 Jun 2014

I have an question concerning the imshow command for GUI. I am processing a lot images and wanted to display the current image using the axes feature. It works fine, only that the whole window gets refreshed everytime a new image is processed. Thats why i can't minimize the window which stays always in the foreground.

What could i do to avoid this?

Code looks like this: It reads some images, does the processing and safes them afterwards.

function execute_Callback(hObject, eventdata, handles)
global filenames
global path
for i=1:length(filenames)
pic = imread(nfilename2);

Thank you!



Max (view profile)


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2 Answers

Answer by Sean de Wolski

Sean de Wolski (view profile)

on 21 Mar 2014
Accepted answer

Specify the parent for imshow to plot to inside of imshow, rather than as axes(handles.axes1)

ax = gca;

Hide figure



Sean de Wolski

Sean de Wolski (view profile)

Answer by Erik

Erik (view profile)

on 5 Jun 2014

The solution from Sean does not seem to work in a gui.

  • Suppose we create a guide with only a single axes 'axes1'.
  • In the OpeningFnc we create, initialize and start a timer object to trigger every 0.1 sec.
  • In the timer callback function we call :

If it runs, then the gui window get on top with every call to imshow. Not so nice for live image analysis applications. Therefor I prefere therefor to use simple image instead of imshow and change the axis to off.

function imshowguitest_OpeningFcn(hObject, eventdata, handles, varargin)
handles.output = hObject;
handles.timer = timer;
handles.timer.StartDelay = 0.1;
handles.timer.Period = 0.1;
handles.timer.ExecutionMode = 'fixedSpacing';
handles.timer.TimerFcn = {@timer_Callback, hObject};
guidata(hObject, handles);
function figure1_CloseRequestFcn(hObject, eventdata, handles)
function timer_Callback(~, ~,hObject)
    handles = guidata(hObject);
%   a = imread('peppers.png');
%   image(a,'parent',handles.axes1);
%   axis(handles.axes1,'off');

1 Comment

Sean de Wolski

Sean de Wolski (view profile)

on 9 Jun 2014

For this I would take a different approach. Instead of rebuilding the image on each iteration, just update its color data ( 'CData' ). See my example here:

hImage = imshow(cat(3,ones(200,400),zeros(200,400,2)));
T = timer('Period',1,'TasksToExecute',10,...
'Timerfcn',@(~,~)set(hImage,'CData',circshift(get(hImage,'CData'),[0 0 1])),...

Full link:


Erik (view profile)

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