How to make the resolution for a spectrogram higher

I'm trying to plot the spectrogram of an auditory stimulus but the resolution looked really low. I tried to change the parameters for the plot but none helped significantly. Is there some specific parameters I can change to make a higher-quality plot? Thank you!

The code I used is as follows:

Fs=44100;

win_size = 0.01;

fft_overlap = 0.3;

hop_size = Fs*win_size;

nfft = round(hop_size/fft_overlap);

noverlap = round(nfft-hop_size);

w = sqrt(hann(nfft)); %use some window

figure

spectrogram(tWaveform, w ,noverlap, nfft, Fs, 'yaxis' );

colormap jet;

set(gca,'YLim', [0,3]);

set(gca,'XLim', [0.4,1.2]);

[Mathieu NOE]

hello

you could still increase the amount of overlap but I f think what would make the plot nicer is to reduce the displayed dB range to 60 or 80 dB (your current plot has a ~110 dB range , so you get a lot of red / orange displayed).

[Mathieu NOE]

following my comment above , and using @Chunru demo code, you can assign a min threshold to your spectrogram plot

IMHO this makes the plot less aggressive :

load handel.mat
tWaveform = y;
Fs=44100;
nfft =1024; 
noverlap = round(.75*nfft);
w = sqrt(hann(nfft)); %use some window 

figure
spectrogram(tWaveform, w ,noverlap, nfft, Fs, 'yaxis' ,'MinThreshold',-100); % remove estimates less than -100 dB
%   [S,F,T,P] = SPECTROGRAM(...,'MinThreshold',THRESH) sets the elements of
%   P to zero when the corresponding elements of 10*log10(P) are less than
%   THRESH. Specify THRESH in decibels. The default value of THRESH is
%   -Inf.

colormap jet;
set(gca,'YLim', [0,3]);
set(gca,'XLim', [0.4,1.2]);

[Freya Guo]

Thank you this has helped!

Answer 1

[Chunru]

load handel.mat
tWaveform = y;

Fs=44100;
win_size = 0.02;            % 20ms
ws = round(win_size*Fs);
noverlap = round(.75*ws);
w = sqrt(hann(ws)); %use some window 
nfft =1024; 

figure
spectrogram(tWaveform, w ,noverlap, nfft, Fs, 'yaxis' );
colormap jet;
set(gca,'YLim', [0,3]);
set(gca,'XLim', [0.4,1.2]);

Answer 2

[Apeksha Bagrecha]

Possible workarounds to this issue are provided below:

1) Open your script as a Live Script and export it as an HTML or other format.

You can do this by right-clicking on the script file in the Current Folder browser and selecting "Open as Live Script". Then run the script and save it to an HTML. In the save dialog box, change the ‘Save as type’ to ‘HTML (*.html)’.

https://www.mathworks.com/help/releases/R2021b/matlab/matlab_prog/create-live-scripts.html?searchHighlight=create-live-scripts&s_tid=doc_srchtitle

https://www.mathworks.com/help/releases/R2021b/matlab/matlab_prog/share-live-scripts.html?searchHighlight=share-live-scripts&s_tid=doc_srchtitle

2) Manually increase the resolution of the figure in your script, save the figure to an image file, and embed the image using publishing markup. e.g.

>>print('test_non_pub','-dpng','-r300')