GUI - Saving multiple files to a pre-specified folder

Hi again everybody,

In this GUI I have made, I want to click 'pushbutton3' to specify a directory where I want to save the processed pictures from my GUI. Here is the code for that pushbutton3 to choose the directory:

% --- Executes on button press in pushbutton3.    SAVE
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)
%Choose which folder processed pics will go in.
save_folder_name = uigetdir;

Ok, so now, when I click the 'run' button (pushbutton1) the code runs a loop in which some pictures are processed. As this loop runs I would like it to save each image every iteration to the folder I specified with pushbutton3. I wrote 'imwrite(handles.outDir)' at the end but then I get this error:

Error using imwrite>parse_inputs (line 498)
Wrong number of input arguments.

Error in imwrite (line 418)
[data, map, filename, format, paramPairs] = parse_inputs(varargin{:});

Error in ROI_loop_gui>pushbutton1_Callback (line 134)
     imwrite(handles.outDir);

Error in gui_mainfcn (line 95)
        feval(varargin{:});

Error in ROI_loop_gui (line 42)
    gui_mainfcn(gui_State, varargin{:});

Error in matlab.graphics.internal.figfile.FigFile/read>@(hObject,eventdata)ROI_loop_gui('pushbutton1_Callback',hObject,eventdata,guidata(hObject))

Error while evaluating UIControl Callback

------------------------------------------------------- Here is my code for pushbutton1:

% --- Executes on button press in pushbutton1.   RUN
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)
 outDir = handles.outDir;

   inDir = handles.inDir;

   %Specify the folder where the files (Pictures) live. Chosen by pushbutton2
  myFolder=handles.outDir;
  %Get a list of all files in the folder with the desired file name pattern.
  filePattern=fullfile(inDir, '*.JPG');
  theFiles=dir(filePattern);
  caListBoxItems = cell(length(theFiles), 1);
  for k=1:length(theFiles)
      RGB = imread(fullfile(inDir, theFiles(k).name));
  %     if k ==1
  %         axes(handles.axes1)
  %         [BW, xi, yi] = roipoly(RGB);
  %         xMin = min(xi);
  %         xMax = max(xi);
  %         yMin = min(yi);
  %         yMax = max(yi);
  %     end

       newRGB = imcrop(RGB,[handles.xMin handles.yMin handles.xMax-handles.xMin handles.yMax-handles.yMin]);

       % Convert RGB image to chosen color space
       I = rgb2hsv(newRGB);

       % Define thresholds for channel 1 based on histogram settings
       channel1Min = 0.053;
       channel1Max = 0.083;

       % Define thresholds for channel 2 based on histogram settings
       channel2Min = 0.116;
       channel2Max = 0.130;

       % Define thresholds for channel 3 based on histogram settings
       channel3Min = 0.608;
       channel3Max = 0.643;

       % Create mask based on chosen histogram thresholds
       BW = (I(:,:,1) >= channel1Min ) & (I(:,:,1) <= channel1Max) & ...
           (I(:,:,2) >= channel2Min ) & (I(:,:,2) <= channel2Max) & ...
           (I(:,:,3) >= channel3Min ) & (I(:,:,3) <= channel3Max);

       % Invert mask
       BW = ~BW;

       % Initialize output masked image based on input image.
       maskedRGBImage = RGB;

       % Set background pixels where BW is false to zero.
       maskedRGBImage(repmat(~BW,[1 1 3])) = 0;

       imwrite(handles.outDir);

   end

%Update handles with the outDir
handles.outDir = save_folder_name;
guidata(hObject,handles);

Any help would be greatly appreciated. This seems like an easy fix but I cannot get it to work!

Thanks,

Ellis

Answer 1

[Geoff Hayes]

Ellis - imwrite requires (at least) two inputs: the image data and the filename. You are calling imwrite as

 imwrite(handles.outDir);

with only one input which is neither an image nor a file name (just a path to some directory). See your other question at http://www.mathworks.com/matlabcentral/answers/288402-gui-saving-image-to-pre-specified-folder which seems to be an updated version of this one.