MATLAB: Display 2 different video in same GUI

2016aMATLABmatlab guimovievideoplay

I am doing a GUI to display 2 video. First video is recorded video, second is the image sequence and need to display at 25 fps. The problem now is i am unable to play 2 video at the same time, just the 1st video played when the button is press. I need to play the 2 video when a button is press. Below is the error after i close the GUI window. Hope someone can help to check where is the error. Thanks.
Error using hgsetdisp (line 8)
Invalid or deleted object.
Error in guitest>pushbutton1_Callback (line 101)
      set(hf2)
Error in gui_mainfcn (line 95)
        feval(varargin{:});
Error in guitest (line 42)
    gui_mainfcn(gui_State, varargin{:});
Error in
matlab.graphics.internal.figfile.FigFile/read>@(hObject,eventdata)guitest('pushbutton1_Callback',hObject,eventdata,guidata(hObject))
Error while evaluating DestroyedObject Callback
Below is My Coding:
      % --- Executes on button press in pushbutton1.
       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)
        Obj = VideoReader('ken-test2_mpeg4.mp4');
        vidFrames = read(Obj);
        vidFrames=imrotate(vidFrames,-90);
        numFrames = get(Obj, 'numberOfFrames'); 
        for k = 1 : numFrames
                    mov(k).cdata = vidFrames(:,:,:,k);
                    mov(k).colormap = [];
        end
        hf = handles.axes1; 
        set(hf)
        movie(hf, mov, 1, Obj.FrameRate);
        Output=evalin('base','imgsequence');
        [~,~,~,numFrames2]=size(Output);
        for l = 1 : numFrames2
                    mov2(l).cdata = Output(:,:,:,l);
                    mov2(l).colormap = [];
        end
        hf2 = handles.axes2; 
        set(hf2)
        movie(hf2, mov2, 1, 25);

Best Answer

Su - I don't think that you will be able to play two videos concurrently using the movie function. I suspect that it blocks so that once it is called with
 movie(hf, mov, 1, Obj.FrameRate);
the subsequent line of code won't fire until this first video completes playback.
As for the error message, it is unclear what may be invalid with handles.axes2. Has this been defined correctly? Does this axes exist within your GUI?
I think what you might want to do is to not use the movie function and display the frames yourself. See http://www.mathworks.com/matlabcentral/answers/216698-how-to-play-my-video-while-my-graph-animates for an example on how you may do this.
If the frame rate for both videos is identical, then you can use one for loop to display each frame for each video (of course, you would have to handle the case where one video is longer (has more frames) than the other).
If the frame rate for each video is different, then your code will have to become smarter. The easiest (?) thing to do maybe to create two timers whose rate is the inverse frame rate for each video. When each timer fires (at different rates) it will display the subsequent frame of the video. So you will need to keep track of the last frame displayed for each video.
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