Making a GUI for playback of wav files

I want to make a GUI were the listener is able to audition two separate sounds (wave files). Something like in the attached image. E.g. 1 = "reference", 2 = "comparison". When the listener hit pushbuton 1, he or she will hear the reference, when hitting pushbotton 2 he or she hear the comparison. Maybe with separate start and stop pusbuttons.

Is it best to you App designer for this?

[Marius Tøndel Eliassen]

I have come so far with my code, but no sound yet. What's next?

%User interface for audition of reference and comparison intervals
f = figure;
fp1 = uipanel('parent',f,'Title','Reference','fontSize',18,'Position',[.170 .50 .200 .200]);
fp2 = uipanel('parent',f,'Title','Comparison', 'fontSize',18,'Position',[.620 .50 .200 .200]);
[y1,Fs] = audioread('Reference_iem_test_0.wav');
[y2,Fs] = audioread('Variable_iem_test_4_0.wav');
pushbutton1 = uicontrol('Style','pushbutton','String','Play','Position',[90 100 50 50]);
pushbutton2 = uicontrol('Style','pushbutton','String','Stop','Position',[170 100 50 50]);
pushbutton3 = uicontrol('Style','pushbutton','String','Play','Position',[340 100 50 50]);
pushbutton4 = uicontrol('Style','pushbutton','String','Stop','Position',[420 100 50 50]);

% --- Executes on button press in pushbutton1.
function pushbutton1_Callback(hObject, eventdata, handles)

global file_name;
if(~ischar(file_name))
    else
    if handles.status==0
        handles.status=1;
        [y1,Fs]=audioread(file_name);
        handles.r=audioplayer1(y1,Fs);
        play(handles.r);
    else
     warndlg({'Warning: Play Is Already In Progress.';' To Begin A New Play You Must First Stop The Current Session.'})    
    end
        guidata(hObject,handles);
end
end
% --- 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 handles.status==1
        handles.status=0;
        [y1,Fs]=audioread(file_name);
        handles.r=audioplayer1(y1,Fs);
        stop(handles.r);
    else
    errordlg('Warning: To Stop, Play Must Be In Progress.')
    end
    guidata(hObject,handles);
end

% --- Executes on button press in pushbutton1.
    function pushbutton3_Callback(hObject, eventdata, handles)

    global file_name;
    if(~ischar(file_name))
    else
    if handles.status==0
        handles.status=1;
        [y2,Fs]=audioread(file_name);
        handles.r=audioplayer2(y2,Fs);
        play(handles.r);

    end
    guidata(hObject,handles);
end
end
% --- Executes on button press in pushbutton4.
function pushbutton4_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 handles.status==1
        handles.status=0;
        [y2,Fs]=audioread(file_name);
        handles.r=audioplayer2(y2,Fs);
        stop(handles.r);
    else
        errordlg('Warning: To Stop, Play Must Be In Progress.')
    end
        guidata(hObject,handles);
end
        

Answer 1

[Geoff Hayes]

Marius - you seem to be programmatically creating your GUI and throwing in GUIDE-style callbacks. You need to assign the callbacks to the controls in order for them to fire. For example, to assign a callback to pushbutton1 you could do

pushbutton1 = uicontrol('Style','pushbutton','String','Play','Position',[90 100 50 50], 'Callback', @pushbutton1_Callback);

and then the signature of this callback would be

function pushbutton1_Callback(hObject, eventdata)

Note how handles has been removed since that is a GUIDE structure. It each callback seems to reference a global variable named file_name yet no where do I see this is defined. If you want to reference the audio files that you have already read (Reference_iem_test_0.wav and Variable_iem_test_4_0.wav), then create a main function that creates your GUI and nest the callbacks within it. For example, if you modify your code slightly to

function MyAudioPlayer

    f = figure;
    fp1 = uipanel('parent',f,'Title','Reference','fontSize',18,'Position',[.170 .50 .200 .200]);
    fp2 = uipanel('parent',f,'Title','Comparison', 'fontSize',18,'Position',[.620 .50 .200 .200]);
    [y1,Fs1] = audioread('Reference_iem_test_0.wav');
    [y2,Fs2] = audioread('Variable_iem_test_4_0.wav');
    
    player1 = audioplayer1(y1,Fs1);
    player2 = audioplayer1(y2,Fs2);
    
    uicontrol('Style','pushbutton','String','Play','Position',[90 100 50 50],  'Callback', @pushbutton1_Callback);
    uicontrol('Style','pushbutton','String','Stop','Position',[170 100 50 50], 'Callback', @pushbutton2_Callback);
    uicontrol('Style','pushbutton','String','Play','Position',[340 100 50 50], 'Callback', @pushbutton3_Callback);
    uicontrol('Style','pushbutton','String','Stop','Position',[420 100 50 50], 'Callback', @pushbutton4_Callback);

    function pushbutton1_Callback(hObject, eventdata)
        % start player1
    end

    function pushbutton2_Callback(hObject, eventdata)
        % stop player1
    end

    function pushbutton3_Callback(hObject, eventdata)
        % start player2
    end

    function pushbutton4_Callback(hObject, eventdata)
        % stop player2
    end

end

and save to a file named MyAudioPlayer.m, then you should be able to start and stop the audio players as desired (I've left that code to you). Because the callbacks are nested within the main function, then the callbacks have access to the local variables declared in the main function (i.e. the player1 and player2 objects).

[Marius Tøndel Eliassen]

Geoff, thanks for answering. With the modified code you posted, unfortunately still no sound. What am I missing?

[Geoff Hayes]

Marius - did you update my code (replacing the comments like % start player1) with the commands to start and stop the audio players? Can you post your updated code?

[Marius Tøndel Eliassen]

Works now:) I have been working all day for a solution so, Geoff many thanks!