Interested in recording(thu USB) and plotting of speech signal in app designer.

Hello , i need to know how i can record my speech/voice and plot it at the same time in app designer. Also need to know how to implement LPF/butterworth. Thank you

Answer 1

[Nikhilesh]

I hope the following steps can guide you.

1. Add an audioRecorder object to your App Designer app. You can do this by adding a button or other UI component that calls a callback function when pressed. In this function, create an audioRecorder object using the audiorecorder function, and set the sample rate and number of channels.
2. Add a loop to continuously read and process audio data. In this loop, use the record method of the audioRecorder object to record a fixed length of audio data (e.g., 0.1 seconds). Then, use the getaudiodata (Store recorded audio signal in numeric array - MATLAB getaudiodata (mathworks.com)) method to retrieve the recorded data as a vector of samples. You can then use this data to compute the spectrum or other characteristics of the audio signal.
3. Plot the audio data in real-time. You can use the plot function to create a line plot of the audio data, and update this plot each time a new chunk of data is recorded.

[Kulbir]

Hi sir. i am trying to follow your way of designing app designer. will reach you if i need. thank you

[Kulbir]

Hi there, i have tried to add audiorecorder. but it's not working. At the beginning, i would like to record , play and save the sound. kindly help me out. thx

%FOR RECORDING
Fs = 44100; 
nBits = 16; 
nChannels = 2; 
ID = -1;       % default audio input device 
app.recObject = audiorecorder(Fs,nBits,nChannels,ID);
msgbox("Begin speaking.")
recDuration = 5; % record for 5 seconds
recordblocking(app.recObject,recDuration);
msgbox("End of recording.")
assignin('base','audioObject',42);

%PLAY
audioObject= evalin('base','audioObject');
            y= getaudiodata(audioObject);%Undefined function 'getaudiodata' for input arguments of type 'double'.
             Fs= audioObject.SampleRate;
            sound(y,Fs);
            
            
            %SAVE
            file1= 'sound.wav';
            audiowrite(file1,y,Fs)
            %play(audioObject)