Visualiser

This project contains the code and instructions (plus links to futher instructions) for creating a real-time audio visualiser.

This is achieved by connecting a RaspberryPi (tested on Raspberry Pi 3 Model B+), to a LED Matrix (tested on a 64x32 led display) via a RGB Hat (tested on Adafruit RGB Hat), and have it visualise, in real-time, the sound picked up on a USB microphone (tested on GOBEST USB Microphone). There are currently 3 patterns implemented, but more can be added with relative ease.

The project also contains code for a webapp, allowing users to select patterns, languages (Italian and English, but again more can be added with relative ease), brightness, colours and more! (well not much more... but still!)

Prerequisites

• Python - Ver. 3.7.1 (https://www.python.org/ftp/python/3.7.1/)
• Flask - Ver. 1.1.2 (https://palletsprojects.com/p/flask/)
• Flask-bootstrap - Ver. 3.3.7.1 (https://github.com/mbr/flask-bootstrap)
• Watchdog - Ver. 0.10.3 (https://github.com/gorakhargosh/watchdog)
• Pillow - Ver. 2.2.2 (https://python-imaging.github.io/)
• Numpy - Ver. 1.19.1 (https://github.com/numpy/numpy)
• PyAudio - Ver. 0.2.11 (http://people.csail.mit.edu/hubert/pyaudio/)

Installation

Installation is not necessary, but the following script can act as a set-up script for using the Visualiser webapp on a RaspberryPi:

#!/bin/bash

#If 'COPF' exists copy logs from Visualiser log path to '/boot/Visualiser_Logs/'
COPF=/boot/COPY-YES
if [ -f "$COPF" ]; then
     sudo rm -r /boot/Visualiser_Logs/*
     sudo cp -Rfa /home/pi/Visualiser/log/. /boot/Visualiser_Logs/
fi

#If 'ZIP' exists containing Visualiser code zip, will move/ unzip it to 'DIRECTORY', overwriting anything there and setting the appropriate permissions
ZIP=/boot/Visualiser.zip
DIRECTORY=/home/pi/Visualiser
if [ -f "$ZIP" ]; then
    if [ -d "$DIRECTORY" ]; then
         sudo rm -rf /home/pi/Visualiser
    fi
    sudo unzip /boot/Visualiser.zip -d /home/pi/
    sudo chmod 777 -R /home/pi/Visualiser
    sudo rm -f /boot/Visualiser.zip
fi

#If 'VCONF_S' exists will allow you to provide a config file for the Visualiser without using the webapp (Assuming 'VCONF_D' is a vaild location)
VCONF_S=/boot/config.txt
VCONF_D=/home/pi/Visualiser/config
if [ -f "$VCONF_S" ]; then
    if [ -d "$VCONF_D" ]; then
	 sudo mv -f /boot/config.txt /home/pi/Visualiser/config/
    fi
fi

exit 0

Notes

• If updating RaspberryPi from 2.7 to 3.7.1, the following may be necessary:

  • Remove Python 2.x:

    
    cd /etc
    sudo apt-get remove python2.7
    sudo apt-get autoremove
    

  • Install libffi-dev:

  
    sudo apt-get install libffi-dev
    

  • Install pip:

  
    sudo apt-get install python-pip
    

  • Update RaspberryPi '~/.bashrc' with:

  
    alias python='/usr/local/bin/python3'
    

• Automatic script start from boot on a RaspberryPi can be achieved by appending the following to the '/etc/rc.local' file:

  
    sh /home/pi/start-visualiser-server.sh
    cd /home/pi/Visualiser/webapp
    python app.py "$_IP" &
  
    cd /home/pi/Visualiser/display/control
    python app.py &
    

Webapp

Specific Prerequisites

• Python - Ver. 3.7.1 (https://www.python.org/ftp/python/3.7.1/)
• Flask - Ver. 1.1.2 (https://palletsprojects.com/p/flask/)
• Flask-bootstrap - Ver. 3.3.7.1 (https://github.com/mbr/flask-bootstrap)

Notes

• Includes and modifies 'Flask-Colorpicker' - Ver. 0.9 (https://github.com/mrf345/flask_colorpicker/) to allow custom assignment of picker's 'cancel' and 'choose' buttons.

• Config file format is as follow:

  {"colour": "rgb([0-255], [0-255], [0-255])", "brightness": "[1-100]", "pattern_type": "[1/2/3]", "ip": "[IP ADDRESS]", "lang": "[en/it]"}

Display

Specific Prerequisites

• Python - Ver. 3.7.1 (https://www.python.org/ftp/python/3.7.1/)
• Watchdog - Ver. 0.10.3 (https://github.com/gorakhargosh/watchdog)
• Pillow - Ver. 2.2.2 (https://python-imaging.github.io/)
• Numpy - Ver. 1.19.1 (https://github.com/numpy/numpy)
• PyAudio - Ver. 0.2.11 (http://people.csail.mit.edu/hubert/pyaudio/)

Notes

• Installation of PyAudio can be tricky, I found this to be helpful: https://www.raspberrypi.org/forums/viewtopic.php?t=25173

• Installation process of RGB Matrix HAT, and corresponding C++ libraries for functionality found at: https://learn.adafruit.com/adafruit-rgb-matrix-plus-real-time-clock-hat-for-raspberry-pi/driving-matrices

• Processing of audio HEAVLY based on the work by Thomas Kou and Hansson Lin (https://github.com/thomaskou/RGB-Matrix-Audio-Visualizer)

• RGB display code HEAVLY based on the work by hzeller (https://github.com/hzeller/rpi-rgb-led-matrix)

• I ran out of time/ patience a bit, so there are hacks here and there. For example, the audio spectrum code only supports seperating the data into a maximum of 16 "segments".