Help for implementing timer function

I have an image containing L and T letters. My task is to show the image to the user and ask if the user could identify the letter L in the image. If the user presses Enter within 60 seconds, it means user can identify the letter. Then, a success message should be shown and the image must be displayed with the letter L in a different place. This process must continue for 10 times. However, if the user is not pressing enter in 60 seconds, the timer ends and a sound is played (say, sound1.wav) indicating wrong entry.

Iam having trouble implementing the timer function. Please help to complete this assignment.

This is the code I have so far:

clf;
for i = 1:10
    image = imread("image5.jpeg");
    imshow(image) %display the image with the letter L in a different place
    user_input = input("Can you identify the letter L in the image? Press enter when you find it.");
    if isempty(user_input)
        disp("Success! The letter L was found.");
    else
        sound("input.wav");
        disp("Letter L not found. Please try again.");
    end

    image = imrotate(image, i*36);
    imshow(image)
    pause(60);
end

Image:

[prasanth s]

may use 'yes' or 'no' input from user (keys 'y' or 'n')

user_input = input("Can you identify the letter L in the image? Press (Y/N)");

Answer 1

[Walter Roberson]

http://psychtoolbox.org/ is the recommended tool for that kind of work. It allows control over timing and detection of key presses

[R Vaidehi]

Hi, thanks for the suggestion. Iam actually trying this on MATLAB online since I dont have the software. I was able to construct a possible solution. There is only one issue remaining. Iam not able to play the audio file in MATLAB file.

The code I used is:

function playSound(HObj, event)

disp("Letter L not found. Please try again.");

[y, Fs] = audioread("input1.wav");

sound(y, Fs);

end

I also tried a workaround, but it's still not working.

function playSound(HObj, event)
[y, Fs] = audioread("lover.wav");
disp("Letter L not found. Please try again.");
aObj = audioplayer(y, Fs, 16, 2);
aObj.play();
end

The argument '2' in audioplayer, I got it from running the following:
info = audiodevinfo;
disp(info.output.ID)


Please let me know If there is any way I can play the audio file. I would greatly appreciate it! Thanks.

[Walter Roberson]

When you use MATLAB Online you can only use sound if you are using the Chrome browser.

[R Vaidehi]

Yes, Iam using Chrome browser only.

[Walter Roberson]

Hmmm, I do not know. sound() is documented to work from Chrome (only) but it did not work on my test (from Mac)