[vs1053b] jack audio input

Hello, I'm contacting you for help with the v1053b audio shield. here
Indeed, I would like with this shield to record audio from the jack "mic" on a variable. Translate the audio into a digit and not into a save file as the examples do.

here

The example here allows you to record sound on a sd card, I would like to record this sound in a variable, roughly in numbers but I can not do it.
Here is the documentation I found.

https://www.elecrow.com/wiki/index.php?title=VS1053_MP3_Shield
http://www.vlsi.fi/en/products/vs1053.html
http://www.vsdsp-forum.com/phpbb/index.php

I would like to make an audio visualiser that takes the sound from the jack
If you can help me, thank you in advance

research arduino oscilloscope. that's the basic concept.

Thank you, I already knew what an oscilloscope was but it's a better way to reformulate my problem.
How to make an oscilloscope with this VS1053 MP3 Shield - Elecrow

I saw how to turn the jack output but I can not make an input in my code

Tanks

I googled for you: link

Your MP3 is overkill for the project. All you have to do is get the signal into arduino... You don't need the shield which does audio encoding for various formats. Try the instructable.

would like to record this sound in a variable,

Simply you can’t. A variable does not contain enough bytes to allow you to do this.

You could store the sound in an array but most Arduinos only have enough memory to store more than a fraction of a second of sound. Even the bigger Arduinos like the Zero only has enough memory for about two seconds of sound.

Now what do you really want to do, not what you think you need to do to to achieve your aims. This is an X-Y problem.

Ok tanks i will try it

Hola
He compilado un buen conjunto de efectos de sonido para usar en mi trabajo.