Music-Visualizer-Reboot

• Terminal-based Music Visualizer that displays the power spectrum of a .wav file
• Music visualizer using SDL2 for audio play and FFTW for Fourier Transformation

Video Demonstration: https://www.youtube.com/watch?v=YaeXZrTrX-Y&t=790s

For simpler version of this code, checkout: https://github.com/Crelloc/terminal-music-visualizer

Motivation

• Was planning to design and build a LED music visualizer as an Arduino project but wanted a better understanding of how music visualization software actually works.

Video Demonstration for LED music visualizer: https://www.youtube.com/watch?v=___XwMbhV4k

Software (prerequisites) to run the program using Docker containers

• Docker server: https://docs.docker.com/engine/install/#server
• Docker Compose: https://docs.docker.com/compose/install/linux/#install-the-plugin-manually

Software (prerequisites) if not using Docker

• SDL2: https://wiki.libsdl.org/SDL2/Installation
  • Note: make sure to install sdl2, alsa, and pulseaudio development (or any development files like pipewire that your systems uses to play sound ) files before installing SDL2.
• FFTW: http://www.fftw.org/download.html
• pkg-config: https://www.freedesktop.org/wiki/Software/pkg-config/
• GDB: for debugging on Linux
• gcc: C compiler for Linux
• make: build automation tool
• Optional (ffmpeg): will be used to convert audio to .wav

How To Build and Run with Docker

Make sure you install docker and docker compose from the links given in the Software (prerequisites) to run the program using Docker containers

Add path to your music folder on your host machine:

edit the .env file:

the .env file should be read by docker-compose.yml by default

ENV_MUSIC_PATH="/home/some_user/Music"

Set path to music folder that has audio files.

Note: this visualizer runs .wav files. If you only have mp3 files you can convert the mp3 files into .wav files using ffmpeg which is automatically installed inside the container using the command:

ffmpeg -i path/to/audio/file output/path/for/.wav

for example:

ffmpeg -i Music/song.mp3 Music/song.wav

MAKE SURE THE FILE PATH AND NAME OF FILE DOESN'T HAVE SPACES AND SPECIAL CHARACTERS IN IT

Build and run docker image:

sudo docker compose build --no-cache && sudo docker compose up --force-recreate --remove-orphans -d

Log into the container:

docker exec -ti visualizer-container bash

Synopsis (run the visualizer):

./visual.exe [-f] /PATH/TO/WAV/AUDIO/FILE

For example:

./visual.exe -f Music/Classic.wav

Note: Supports only wav audio files and make sure that the "/PATH/TO/WAV/AUDIO/FILE" doesn't have spaces in it.

Stop container:

sudo docker stop visualizer-container

Troubleshooting audio not playing:

Check for the correct path of audio socket on your system:

pactl info | grep '^Server String';

and add the correct path in docker-compose.yml

...
volumes:
    ...
  - /run/user/1000/pulse/native:/tmp/pulse/native
...

Other troubleshooting references:

• https://gist.github.com/the-spyke/2de98b22ff4f978ebf0650c90e82027e?permalink_comment_id=3976309
• https://stackoverflow.com/questions/28985714/run-apps-using-audio-in-a-docker-container/75775875#75775875
• https://leimao.github.io/blog/Docker-Container-Audio/

How To Build and Run without docker

Install prerequisites:

For Ubuntu (or debian-based):

sudo apt-get update && sudo apt-get install gdb gcc pkg-config make

if your system is using pulseaudio to play sound install the development files for pulseaudio and alsa

sudo apt-get install libasound2-dev libpulse-dev 

if your system is using pipewire to play sound install the development files for pipewire

sudo apt-get install libpipewire-0.3-dev libspa-0.2-dev 

Install sdl2 development files and sdl application

sudo apt-get install libsdl2-dev libsdl2-2.0-0

clone repo and change directory into it:

git clone https://github.com/Crelloc/Music-Visualizer-Reboot.git && cd Music-Visualizer-Reboot

Install fftw3.3.4.tar.gz from project directory or install updated version from http://www.fftw.org/download.html

tar -xvf fftw-3.3.4.tar.gz && \
cd fftw-3.3.4 && \
chmod +x ./configure && \
./configure && \
make && \
sudo make install

Go back to project directory and reate executable for visualize.c

cd .. && make

Synopsis:

./visual.exe [-f] /PATH/TO/WAV/AUDIO/FILE

For example:
./visual.exe -f ~/Music/Classic.wav

Note: Supports only wav audio files and make sure that the "/PATH/TO/WAV/AUDIO/FILE" doesn't have spaces in it.

Brief overview about how the program works

• Analyzes the digital information in the wav file.
• Computes the fourier transformation every 'N' frames. Eg. computes the fourier transformation (FT) on 'N' L channel data and also computes the FT on 'N' R channel data.
• Gathers frequency and magnitude information from the results of the fourier transformation and records it by storing into an array.
• After analysis is finished the program will play music and display the corresponding information at the terminal.