31 ●5 How to use Dynamic Time Warping (DTW) algorithm in matlab?

I am new in matlab. I've been browsing for few hours and I'm still getting errors. I want to know how to use dtw algorithm in matlab and I want to know the output of these two audio files using dtw algorithm. this is my code:

fftNyol = fft(audioread('C:\Users\handy\Documents\MATLAB\my_recording_1.wav'));
fftFajar = fft(audioread('C:\Users\handy\Documents\MATLAB\fajar.wav'));
dist = dtw(fftNyol,fftFajar);

this is error message from matlab:

Error using zeros
Requested 137281x87361 (89.4GB) array exceeds maximum array size preference. Creation of arrays greater than this limit
may take a long time and cause MATLAB to become unresponsive. See array size limit or preference panel for more
information.

Error in dtw (line 27)
D=zeros(ns+1,nt+1)+Inf; % cache matrix

Error in test (line 15)
dist = dtw(fftNyol,fftFajar);

Answer 1

[Walter Roberson]

You are not using Mathworks dtw() from the signal processing toolbox. Mathworks dtw() has comments at line 27.

[Mohamad Handy Nugraha]

how can I use the features of the signal processing toolbox? I am on trial version matlab

[Walter Roberson]

What currently shows up when you use

which -all dtw

[Mohamad Handy Nugraha]

in command line? show this: C:\Program Files\MATLAB\R2017b\toolbox\signal\signal\dtw.m

[Walter Roberson]

At the command line command

dbstop if error

and then run your call to test . When it stops in line 27 of dtw, please give the command

dbstack -completenames

and show the result.

Is it possible that your test function includes a cd() or an addpath() ?

[Mohamad Handy Nugraha]

I run again the program and got the new error:

Error using dtw (line 87)
The number of rows between X and Y must be equal when X and Y are matrices

Error in test (line 15)
dist = dtw(fftNyol,fftFajar);

Is it possible that your test function includes a cd() or an addpath() ? I don't understand what do you mean, sorry I am new in matlab

[Walter Roberson]

I think you are past the original problem, whatever it is.

Now you have the problem that your wav files are different lengths (different number of samples.)

[Wu Sunner]

Hi~~

you just transportation "fftNyol" & "fftFajar"

ex:

vec1 = [1 2 3 4 5];

vec11 = vec1';

you can try to do:

fftNyol_tr = fftNyol';

fftFajar_tr = fftFajar';

dist = dtw(fftNyol_tr, fftFajar_tr);

Because :

dist = dtw( x , y ) stretches two vectors, x and y , onto a common set of instants such that dist , the sum of the Euclidean distances between corresponding points, is smallest. To stretch the inputs, dtw repeats each element of x and y as many times as necessary. If x and yare matrices, then dist stretches them by repeating their columns. In that case, x and y must have the same number of rows.