GUI IN IMAGE PROCCESSING MATLAB

function upload_Callback(hObject, eventdata, handles) % hObject handle to upload (see GCBO) % eventdata reserved - to be defined in a future version of MATLAB % handles structure with handles and user data (see GUIDATA) a=uigetfile() filename=a; setappdata(0,'filename',filename); a=imread(a); axes(handles.axes1); imshow(a); setappdata(0,'a',a) setappdata(0,'filename',a); plot(handles.axes1,'a') % --- Executes on button press in rgb_gray. function rgb_gray_Callback(hObject, eventdata, handles) % hObject handle to rgb_gray (see GCBO) % eventdata reserved - to be defined in a future version of MATLAB % handles structure with handles and user data (see GUIDATA) a=getappdata(0,'a'); a_gray=RGB2GRAY(a,1); axes(handles.axes2); imshow(a_gray) setappdata(0,'filename',a_gray); % --- Executes on button press in histogram. function histogram_Callback(hObject, eventdata, handles) % hObject handle to histogram (see GCBO) % eventdata reserved - to be defined in a future version of MATLAB % handles structure with handles and user data (see GUIDATA) a=getappdata(0,'a'); histo=a; axes(handles.axes2) histogram_rgb_gray(histo)