# How to combine multiple spectrogram and create a single image in MATLAB

조회 수: 14(최근 30일)
Stephen john 2022년 9월 12일
댓글: Walter Roberson 2022년 9월 25일
Hello I hope you are doing well. I have the 3 vectors. I want to create a spectrogram of each vectors first save the spectrogram.
and combine the three vectors to create a single overlap spectrogram and save as image file
How can i do it in MATLAB

댓글을 달려면 로그인하십시오.

### 답변(1개)

Walter Roberson 2022년 9월 12일
When you permit spectrogram() to display the result, then it always clears the axes it is drawing in. spectrogram() does not just display the result: the output has active controls.
Because of this, if you let spectrogram() display the output, you cannot merge the results at all easily.
What you can do is ask for outputs from spectrogram(), and use the outputs to draw the results any way that is appropriate for you.
But perhaps I am misunderstanding you. Perhaps what you want to do is something more like
combined_signal = mean([first_signal(:), second_signal(:), third_signal(:)], 2);
This assumes that they are all the same length; if not then you will need to pad the shorter ones first.
##### 댓글 수: 13표시숨기기 이전 댓글 수: 12
Walter Roberson 2022년 9월 25일
s_rate=200;
dt=1/s_rate;
n = 1;
nov = length(acc(:,n)); %my acc has the dimensions (262144,1)
section1 = ceil(nov/13); %window my acc data in 13 segments
window1 = hanning(section1); %apply a hanning fenster on it
noverlap1 = ceil(3*section1/4); %75% overlapping
f= [0 100]; %my frequencies go from 0 30-40 Hz so i choose to take max f intervall
[s,f,t,psd] =spectrogram(acc,section1,noverlap1,f,s_rate,'psd');

댓글을 달려면 로그인하십시오.

### 범주

Find more on Descriptive Statistics in Help Center and File Exchange

R2022a

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!