How to mix two sound of different channel?

Here is my code

handles.y = (handles.y2)'; lenY = size(handles.y1, 1); lenZ = size(handles.y, 1);

        handles
        len = max(lenY, lenZ);
        S = zeros(len, size(handles.y1, 2));

        S(1:lenY, :) = handles.y1;

        S(1:lenZ, :) = S(1:lenZ, :) + handles.y;

        maxValue = max(abs(S(:)));

        S = S / maxValue;
        handles.mPlayer = audioplayer(S, 44100);
        handles.y3 = S;
        handles.Fs3 = 44100;
        % save the updated handles object
        guidata(hObject,handles);
        msgbox('Sound Mixed');

[Birdman]

What is your code that causes this error?

[Sushil Pun]

y2 has number of channel 1 and y has number of channel 2, i think thats causing a problem i don't know how to fix it, i have provided the code above.

Answer 1

[John Harris]

It's that you're trying to add 1-dimensional and 2-dimensional matrix, but look at your dimensions for y1 and y. y1 (and thus, S) is tall, while handles.y is wide.

Try transposing handles.y:

S(1:lenZ, :) = S(1:lenZ, :) + handles.y';

Check the results; are you trying to add handles.y to one column of S, or both?

Answer 2

[Jan]

Insert some meaningful comments in your code, such that it gets clear, what you want to achieve. I assume, you want to mix the 2 channel handles.y1 and the 1 channel handles.y - by the way: there might be more useful names for the fields.

I omit the "handles" for clarity:

y1 = rand(220500, 2) - 0.5;
y  = rand(1, 220501) - 0.5;

s1 = y1;
s2 = y.';  % Transpose to have the same orientation

[len1, w1] = size(s1);
[len2, w2] = size(s2, 1); 
s          = zeros(max(len1, len2), max(w1,w2));
s(1:len1, 1:w1) = s1;
s(1:len2, 1:w2) = s(1:len2, 1:w2) + s2;
s          = s / max(s(:));   % Normalize to [-1.0, 1.0]

This adds the two signals independent from their number of channels and lengths.