How to create a GUI to play, pause, fast forward and rewind video in MATLAB?

Question

I am a newbie to MATLAB. I am trying to create a GUI to play, pause, fast forward and rewind an avi video frame by frame. At the moment I can play and pause the video, via a toggle button, but when I press play again the video plays from frame zero. I realise I need to store the frame number to be used the next time I press play but I don't know how to do this. Any help would be much appreciated. I realise there is an implay option in MATLAB but I have some other code to implement which I have already got right and that is why I want to create my own GUI. Below is the code to pause/play the video.

My most recent code looks like,

   function varargout = N_Play_Pause_2(varargin)
% N_PLAY_PAUSE_2 MATLAB code for N_Play_Pause_2.fig
%      N_PLAY_PAUSE_2, by itself, creates a new N_PLAY_PAUSE_2 or raises the existing
%      singleton*.
%
%      H = N_PLAY_PAUSE_2 returns the handle to a new N_PLAY_PAUSE_2 or the handle to
%      the existing singleton*.
%
%      N_PLAY_PAUSE_2('CALLBACK',hObject,eventData,handles,...) calls the local
%      function named CALLBACK in N_PLAY_PAUSE_2.M with the given input arguments.
%
%      N_PLAY_PAUSE_2('Property','Value',...) creates a new N_PLAY_PAUSE_2 or raises the
%      existing singleton*.  Starting from the left, property value pairs are
%      applied to the GUI before N_Play_Pause_2_OpeningFcn gets called.  An
%      unrecognized property name or invalid value makes property application
%      stop.  All inputs are passed to N_Play_Pause_2_OpeningFcn via varargin.
%
%      *See GUI Options on GUIDE's Tools menu.  Choose "GUI allows only one
%      instance to run (singleton)".
%
% See also: GUIDE, GUIDATA, GUIHANDLES

% Edit the above text to modify the response to help N_Play_Pause_2

% Last Modified by GUIDE v2.5 29-Aug-2013 08:39:38

% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @N_Play_Pause_2_OpeningFcn, ...
                   'gui_OutputFcn',  @N_Play_Pause_2_OutputFcn, ...
                   'gui_LayoutFcn',  [] , ...
                   'gui_Callback',   []);
if nargin && ischar(varargin{1})
    gui_State.gui_Callback = str2func(varargin{1});
end

if nargout
    [varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
    gui_mainfcn(gui_State, varargin{:});
end
% End initialization code - DO NOT EDIT


% --- Executes just before N_Play_Pause_2 is made visible.
function N_Play_Pause_2_OpeningFcn(hObject, eventdata, handles, varargin)
% This function has no output args, see OutputFcn.
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% varargin   command line arguments to N_Play_Pause_2 (see VARARGIN)

% Choose default command line output for N_Play_Pause_2
handles.output = hObject;
handles.VidObj = VideoReader('x05.avi');
handles.nFrames = handles.VidObj.NumberOfFrames;
handles.videoPos = 1; %Current video position. Starts at 1.

% Update handles structure
guidata(hObject, handles);

% UIWAIT makes N_Play_Pause_2 wait for user response (see UIRESUME)
% uiwait(handles.figure1);


% --- Outputs from this function are returned to the command line.
function varargout = N_Play_Pause_2_OutputFcn(hObject, eventdata, handles) 
% varargout  cell array for returning output args (see VARARGOUT);
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Get default command line output from handles structure
varargout{1} = handles.output;


% --- Executes on button press in togglebutton1.
function togglebutton1_Callback(hObject, eventdata, handles)
% hObject    handle to togglebutton1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hint: get(hObject,'Value') returns toggle state of togglebutton1
while get(hObject,'Value')
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
     if handles.videoPos >= handles.nFrames % Protect your code not to go be number of frames available
      break;
    end
    handles.videoPos=handles.videoPos+1;     % Increment the stored position
    imshow(snapshot),title(handles.videoPos);
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle
set(hObject,'Value',false);


% --- 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)
if get(hObject,'Value')
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
    handles.videoPos=handles.videoPos+1;     % Increment the stored position
    imshow(snapshot),title(handles.videoPos);
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle
set(hObject,'Value',false);


% --- Executes on button press in pushbutton2.
function pushbutton2_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton2 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
if get(hObject,'Value')
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
    handles.videoPos=handles.videoPos-1;     % Increment the stored position
    imshow(snapshot),title(handles.videoPos);
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle
set(hObject,'Value',false);


% --- Executes on button press in pushbutton3.
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)
if get(hObject,'Value')
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
    handles.videoPos=handles.videoPos+10;     % Increment the stored position
    imshow(snapshot),title(handles.videoPos);
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle
set(hObject,'Value',false);


% --- Executes on button press in pushbutton4.
function pushbutton4_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton4 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
if get(hObject,'Value')
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
    handles.videoPos=handles.videoPos-10;     % Increment the stored position
    imshow(snapshot),title(handles.videoPos);
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle
set(hObject,'Value',false);

Werner · Accepted Answer · 2013-08-28T20:13:33.243

Final solution

So, I haven't seen that you updated your code. Seeing your code is quite easier, it seems that you are incrementing after you show your image, so if you push the play button it will show the image before

function varargout = N_Play_Pause2(varargin)
% N_PLAY_PAUSE2 MATLAB code for N_Play_Pause2.fig
%      N_PLAY_PAUSE2, by itself, creates a new N_PLAY_PAUSE2 or raises the existing
%      singleton*.
%
%      H = N_PLAY_PAUSE2 returns the handle to a new N_PLAY_PAUSE2 or the handle to
%      the existing singleton*.
%
%      N_PLAY_PAUSE2('CALLBACK',hObject,eventData,handles,...) calls the local
%      function named CALLBACK in N_PLAY_PAUSE2.M with the given input arguments.
%
%      N_PLAY_PAUSE2('Property','Value',...) creates a new N_PLAY_PAUSE2 or raises the
%      existing singleton*.  Starting from the left, property value pairs are
%      applied to the GUI before N_Play_Pause2_OpeningFcn gets called.  An
%      unrecognized property name or invalid value makes property application
%      stop.  All inputs are passed to N_Play_Pause2_OpeningFcn via varargin.
%
%      *See GUI Options on GUIDE's Tools menu.  Choose "GUI allows only one
%      instance to run (singleton)".
%
% See also: GUIDE, GUIDATA, GUIHANDLES

% Edit the above text to modify the response to help N_Play_Pause2

% Last Modified by GUIDE v2.5 23-Aug-2013 13:50:30

% Begin initialization code - DO NOT EDIT
gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @N_Play_Pause2_OpeningFcn, ...
                   'gui_OutputFcn',  @N_Play_Pause2_OutputFcn, ...
                   'gui_LayoutFcn',  [] , ...
                   'gui_Callback',   []);
if nargin && ischar(varargin{1})
    gui_State.gui_Callback = str2func(varargin{1});
end

if nargout
    [varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
    gui_mainfcn(gui_State, varargin{:});
end
% End initialization code - DO NOT EDIT


% --- Executes just before N_Play_Pause2 is made visible.
function N_Play_Pause2_OpeningFcn(hObject, eventdata, handles, varargin)
% This function has no output args, see OutputFcn.
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% varargin   command line arguments to N_Play_Pause2 (see VARARGIN)

handles.output = hObject;
handles.VidObj = VideoReader('x05.avi');
handles.nFrames = handles.VidObj.NumberOfFrames;
handles.videoPos = 1; % Current video position, starts at first frame.

snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
imshow(snapshot),title(handles.videoPos);

% Choose default command line output for N_Play_Pause2
handles.output = hObject;

% Update handles structure
guidata(hObject, handles);

% UIWAIT makes N_Play_Pause2 wait for user response (see UIRESUME)
% uiwait(handles.figure1);


% --- Outputs from this function are returned to the command line.
function varargout = N_Play_Pause2_OutputFcn(hObject, eventdata, handles) 
% varargout  cell array for returning output args (see VARARGOUT);
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Get default command line output from handles structure
varargout{1} = handles.output;


% --- Executes on button press in togglebutton1.
function togglebutton1_Callback(hObject, eventdata, handles)
% hObject    handle to togglebutton1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hint: get(hObject,'Value') returns toggle state of togglebutton1

while get(hObject,'Value')  && handles.videoPos < handles.nFrames 
    handles.videoPos=handles.videoPos+1;     % Increment the stored position
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
    imshow(snapshot),title(handles.videoPos);
    end
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle

% --- 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)
if get(hObject,'Value')
    handles.videoPos=handles.videoPos+1;     % Increment the stored position
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
    imshow(snapshot),title(handles.videoPos);
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle


% --- Executes on button press in pushbutton2.
function pushbutton2_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton2 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
if get(hObject,'Value') && handles.videoPos>1
    handles.videoPos=handles.videoPos-1;     % Increment the stored position
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
    imshow(snapshot),title(handles.videoPos);
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle


% --- Executes on button press in pushbutton3.
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)
if get(hObject,'Value') && handles.videoPos<handles.nFrames-9
    handles.videoPos=handles.videoPos+10;     % Increment the stored position
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
    imshow(snapshot),title(handles.videoPos);
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle


% --- Executes on button press in pushbutton4.
function pushbutton4_Callback(hObject, eventdata, handles)
% hObject    handle to pushbutton4 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
if get(hObject,'Value') && handles.videoPos>10
    handles.videoPos=handles.videoPos-10;     % Increment the stored position
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
    imshow(snapshot),title(handles.videoPos);
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle

Seems you got confused a little bit with the coding, I've edited it and commented your errors. They are preceded by % COMMENT:

function varargout = N_Play_Pause(varargin)
% N_PLAY_PAUSE MATLAB code for N_Play_Pause.fig
%      N_PLAY_PAUSE, by itself, creates a new N_PLAY_PAUSE or raises the existing
%      singleton*.
%
%      H = N_PLAY_PAUSE returns the handle to a new N_PLAY_PAUSE or the handle to
%      the existing singleton*.
%
%      N_PLAY_PAUSE('CALLBACK',hObject,eventData,handles,...) calls the local
%      function named CALLBACK in N_PLAY_PAUSE.M with the given input arguments.
%
%      N_PLAY_PAUSE('Property','Value',...) creates a new N_PLAY_PAUSE or raises the
%      existing singleton*.  Starting from the left, property value pairs are
%      applied to the GUI before N_Play_Pause_OpeningFcn gets called.  An
%      unrecognized property name or invalid value makes property application
%      stop.  All inputs are passed to N_Play_Pause_OpeningFcn via varargin.
%
%      *See GUI Options on GUIDE's Tools menu.  Choose "GUI allows only one
%      instance to run (singleton)".
%
% See also: GUIDE, GUIDATA, GUIHANDLES

% Edit the above text to modify the response to help N_Play_Pause

% Last Modified by GUIDE v2.5 13-Aug-2013 16:26:32

% Begin initialization code - DO NOT EDIT

gui_Singleton = 1;
gui_State = struct('gui_Name',       mfilename, ...
                   'gui_Singleton',  gui_Singleton, ...
                   'gui_OpeningFcn', @N_Play_Pause_OpeningFcn, ...
                   'gui_OutputFcn',  @N_Play_Pause_OutputFcn, ...
                   'gui_LayoutFcn',  [] , ...
                   'gui_Callback',   []);
if nargin && ischar(varargin{1})
    gui_State.gui_Callback = str2func(varargin{1});
end

if nargout
    [varargout{1:nargout}] = gui_mainfcn(gui_State, varargin{:});
else
    gui_mainfcn(gui_State, varargin{:});
end
% End initialization code - DO NOT EDIT


% --- Executes just before N_Play_Pause is made visible.
function N_Play_Pause_OpeningFcn(hObject, eventdata, handles, varargin)
% This function has no output args, see OutputFcn.
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)
% varargin   command line arguments to N_Play_Pause (see VARARGIN)

% Choose default command line output for N_Play_Pause
handles.output = hObject;
handles.VidObj = VideoReader('x05.avi'); % COMMENT: PAY ATTENTION, 's' was missing!
handles.nFrames = handle.VidObj.NumberOfFrames;
handles.videoPos = 1; % Current video position, starts at first frame.

% Update handles structure
guidata(hObject, handles); % Here you are saving the handles method at the hObject, this is the handle from your GUI figure.

% COMMENT: In the original code here, you would save guidata twice, you didn't need that, just save guidata after you make ALL ALTERATIONS IN IT!


% --- Outputs from this function are returned to the command line.
function varargout = N_Play_Pause_OutputFcn(hObject, eventdata, handles) 
% varargout  cell array for returning output args (see VARARGOUT);
% hObject    handle to figure
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Get default command line output from handles structure
varargout{1} = handles.output;


% --- Executes on button press in togglebutton1.
function togglebutton1_Callback(hObject, eventdata, handles)
% hObject    handle to togglebutton1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hint: get(hObject,'Value') returns toggle state of togglebutton1


while get(hObject,'Value')
    snapshot = read(handles.VidObj,handles.videoPos); % Here we use the stored video position 
    imshow(snapshot),title(double2str(handles.videoPos));            
    if handles.videoPos >= handles.nFrames % Protect your code not to go be number of frames available
      break;
    end
    handles.videoPos=handles.videoPos+1;     % Increment the stored position
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle

Reading your question title I was like, what else you need? Do you also want a desert? But jokes a part, I was wrong, at least you have something working.

I am not an image specialist at matlab, but instead doing a = 0 in your callback function (and therefore reseting your video to start position), you will need to save your video position at your GUI. There are several ways of doing it, one way would be by using guidata, setappdata, or to pass it via arguments to your callbacks. You could call it a variable videoPos and add it to the handles struct that you store with guidata. Also save your nFrames variable in this struct.

The fast forward would be the same as you showed, but instead doing videoPos = videoPos + 1 you would do videoPos = videoPos + n, where n is the speed multiplier you want on the fast forward. To rewind, just decrement your videoPos, or reset it to 1, depending what you want.

Note: Don't forget to add checkers, you won't want your videoPos lesser than 0 or greater than nFrames.

On the function: N_Play_Pause_OpeningFcn Add the following data:

handle.VidObj = VideoReader('x05.avi');
handle.nFrames = VidObj.NumberOfFrames;
handle.videoPos = 1; % Current video position, starts at first frame.

% Update handles structure
guidata(hObject, handles); % Here you are saving the handles method at the hObject, this is the handle from your GUI figure.

Then, at your function togglebutton1_Callback do:

% --- Executes on button press in togglebutton1.
function togglebutton1_Callback(hObject, eventdata, handles)
% hObject    handle to togglebutton1 (see GCBO)
% eventdata  reserved - to be defined in a future version of MATLAB
% handles    structure with handles and user data (see GUIDATA)

% Hint: get(hObject,'Value') returns toggle state of togglebutton1


% You won't need this line anymore a=0;
% If you would like to retrieve the stored guidata you would do it here, by doing **handles=guidata(hObject);** but this is not needed, the handles data stored at the figure handle is already given to you as the third argument internally by the matlab!    

while get(hObject,'Value')
    snapshot = read(VidObj,handles.videoPos); % Here we use the stored video position 
    imshow(snapshot),title(double2str(handles.videoPos));            
    if handles.videoPos >= handles.nFrames % Protect your code not to go be number of frames available
      break;
    end
    handles.videoPos=handles.videoPos+1;     % Increment the stored position
end
guidata(hObject,handles) % Save the modifications done at the handles structure at the figure handle

Note that you need to update the guidata everytime you quit your methods, so that you keep it updated and saved on the figure handle. One more detail is that the object you pass for the guidata don't need to be the figure handle, but any object holden by it, as the play button you have created. As in the guidata help:

GUIDATA(H, DATA) stores the specified data in the figure's application data.
H is a handle that identifies the figure - it can be the figure
itself, or any object contained in the figure.

Now just add more buttons and work with the togglebutton1 method, the fastforward would be the same, but using instead of +1, +n.

Hi Werner, thanks for the reply. I have been making an attempt to use guidata but I can't get it working. Could you show me an example of how it works. Thank you in advance. — Norman, Aug 21 '13 at 14:07
@Norman Add more information to your question, what are you trying? It's quite difficult to help you with the amount of information you have provided. — Werner, Aug 21 '13 at 14:14
I am trying to pause play a video. When I press play again I would like to play from the frame at which I paused. How would I save the frame number using GUIDATA and then use that information when I press play again to play the video from that position. — Norman, Aug 21 '13 at 14:23
@Norman What I've meant is how is your code, what errors are you having? Update it by editing your question. — Werner, Aug 21 '13 at 14:25
@Norman don't forget to notify me, otherwise I won't know you have updated it. — Werner, Aug 21 '13 at 14:30
Hi Werner, I appreciate your help but I haven't got the code working yet. Upon entering your code I got this error. — Norman, Aug 22 '13 at 15:25
Could you have a look at what I have done and comment please. Any help is appreciated. — Norman, Aug 22 '13 at 15:41
I got the code working, just had to make one change. In your code you had "handles.nFrames = handle.VidObj.NumberOfFrames;" , where as I had to change it to "handles.nFrames = handles.VidObj.NumberOfFrames;" to make it work. I've already added extra buttons with little effort. Thanks very much for your help, I now have a basic understanding of handle/handles. — Norman, Aug 23 '13 at 09:42
Werner, I have all buttons included in my GUI and they work but only after they execute the previous buttons function first. What I'm saying is if I pause video, fast forward by 10 frames and then try and rewind by 10 frames it will first fast forward by 10 frames before I'm able to rewind by 10 frames. — Norman, Aug 23 '13 at 13:15
@Norman, you need to add to your whiles to listen to the other button callbacks. They are stored at the `handles` variable with names like `togglebutton1` `togglebutton2` and so on, if you haven't edit the `tag` property in the guide (the variable name is exactly as their tag). You can get their value as you do with the `get(hObject,'Value')`, but instead using `hObject` you will use `get(handles.togglebutton2,'Value')`. So, you can watch if the user push another button and interrupt the `while` loop. **Make sure you add after the loop set(hObject,'Value',false)** — Werner, Aug 23 '13 at 17:21
@Norman **so that you turn of the current button and make the other buttons execution work** — Werner, Aug 23 '13 at 17:22
Werner, is it possible to implement your method into if statements. In my code I am only using one while loop and the rest are if statements for the buttons. Also do I have to instruct each button to listen out for every other button? Thank you in advance. — Norman, Aug 26 '13 at 10:59
@Norman For every other button that matters. If you have play pause fastforward and rewind, and you want play to stop listening to every other one of these buttons, yes, you will need to listen to everyone of them, and the same thing for the other buttons, there is no magic in programing, you need to program what you want to happen. Well, you can use ifs, but the while condition is a if itself, you can attach those conditions to the while conditions with `&&` — Werner, Aug 26 '13 at 14:41
I'm not fully understanding your last advice. My problem was that after using a button, say, forward by 10 frames and then wanting to use any other button, upon pressing any other button the next thing that would happen is the video would move forward by 10 frames before doing what it was supposed to do. What I'm wondering is there something to the effect of "clear all" that I could put in at the end of each of the loops so that the next button pressed, works first time without first running the preious buttons action. — Norman, Aug 27 '13 at 10:07
@Norman This question is getting too broad and it is very difficult to understand what is happening, but it seems that you need to add `set(hObject,'Value',false)` after the while. — Werner, Aug 27 '13 at 18:09
I would agree that I need to use set(hObject,'Value',false) or something to that effect but I cannot get it to work. I have put this line under my while loop but it is having no effect on the code. When I run the program and press any button, the previous button pressed is executed before the one I just pressed. e.g. If I play the video, then pause, and then I want to rewind by 10 frames, upon pressing the rewind button it first executes the previous button, which was the play button. So it goes forward by 1 frame and then the next time I press the rewind button it works. — Norman, Aug 28 '13 at 08:20
@Norman, I havent seen that you updated your code at your question, now everything makes sense. You are updating your frame after you show it. So, the actual pos were always shown before the action was taken. That is why you would see the play action only when you pushed the rewind button and so on. So, what you had to do is to do the action of updating you position before you plot you image. — Werner, Aug 28 '13 at 20:15
Werner, I have rearranged the code as you said and my frame number is correct as I play, rewind and fast forward. But it is obvious that the program still isn't perfect. As I press any button the program still executes the previously pressed button and not the one I just pressed. The line `set(hObject,'Value',false)` appears to do nothing. Thank you in advance. — Norman, Aug 30 '13 at 13:09
@Norman you must increment your `videoPos` **before** you take the snapshot (`snapshot = read(handles.VidObj,handles.videoPos);`). I've updated the code, check if it works. — Werner, Aug 30 '13 at 15:09
Werner, you're a hero. The program works exactly as I wanted it to. I don't know how to thank you. All I can say is have a very good weak and thanks. — Norman, Sep 02 '13 at 09:43
@Norman well, I'm glad to hear that your program works how you wanted x). Don't forget to accept the answer to close the thread. Also have a nice week. — Werner, Sep 02 '13 at 19:33

How to create a GUI to play, pause, fast forward and rewind video in MATLAB?

1 Answers1

Final solution

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