Error in ==> main_gui>pushbutton1_Callback at 105
imread(strcat(f1,f2{2,1}));
Error in ==> gui_mainfcn at 96
feval(varargin{:});
Error in ==> main_gui at 42
gui_mainfcn(gui_State, varargin{:});
Error in ==>
@(hObject,eventdata)main_gui('pushbutton1_Callback',hObject,eventdata,guidata(hObject))
??? Error while evaluating uicontrol Callback