How to read .m4a and .wv audio file formats in matlab 2015b ?

Hello everyone

How to read .m4a and .wv audio file formats in matlab 2015b ?

I've tried it with this format :

[y,Fs] = audioread('water.m4a');

but there is an error :

Error using audioread (line 88)

Failed to initialize internal resources.

Error in test4 (line 9)

[y,Fs] = audioread('water.m4a');

Why does this happen and how to solve it?

Thank you

[Walter Roberson]

Which operating system are you using?

[sisi chalisva]

Windows 8 (32bit), matlab 2015b

[Johannes Stache]

Hi guys,

in my case reading the .m4a file works (I got Matlab R2020b) with " [y fs]=audioread('background_noise.m4a') ".

But but my data -> y <- is stored as 46080x2 double. Why do i have two columns with data instead of just one (46080x1 double for example)? I mean it is a basic audio file, isn't it? Also both data series/data columns have slightly different values.

I would be super happy for a quick reply/answer! :D

Best regards,

Jojo

[Walter Roberson]

Two columns implies stereo.

[Johannes Stache]

Understood, I got 2 audio channels. That explains my question, thank you!

For my application I want to apply further signal analysis und signal processing techniques (such as FFT, PSD, etc.).

I am wondering now:

Should I take the average/mean of both signals [-> (signal_A+signal_B) / 2 ] and perform my analysis afterwords or should i treat both signals independently?

What could you recommend @Walter Roberson (or other users)?

[Walter Roberson]

We do not know the context. In some contexts, mixing down to mono is fine; in other contexts, the stereo nature is very important.

Answer 1

[Walter Roberson]

R2015b did not directly support reading .m4a files on MS Windows -- only on Linux and Mac.

It did, however, say that files supported by Microsoft's Media Foundation might also be usable.

You could therefore experiment with downloading an extensive codec package, such as from https://www.mediaplayercodecpack.com/ and see if that happens to solve your problem.

I was not familiar with .wv (WavePack) files https://en.wikipedia.org/wiki/WavPack . I do not see any direct MATLAB support for any release. If they do not happen to be supported by the above codec pack, then you might need to use https://github.com/dbry/WavPack and call into a DLL from MATLAB .

... Or you could get something like VLC https://www.videolan.org/ and use it in command line mode to transcode the .wv file into a different file format that your release could use.

[sisi chalisva]

Okay Mr, I will try

Thank you so much