audioviz

my own audio visualizer (library), because after effects sucks

features

• low-level visualizer building
• layer-and-effect-based graphics API for C++ & Lua
• super fast video rendering with ffmpeg
• faster than adobe after effects!!!!!!!!!

here are some songs rendered with audioviz!

how things work

below is a great video explaining some of the fundamentals of programming with audio. it will get you up to speed with a decent chunk of the codebase:

Cinamark - How do computers even render audio...?

building & running

all platforms

make sure you are running executables from the project root directory (the folder you git cloned)! this is because audioviz needs to find effect shader files, which are in shaders, and not copied to the build directory. (will change this eventually by having the shaders embedded in source code at compile time).

linux

1. install any required dependencies below
2. run cmake -S. -Bbuild && cmake --build build -j$(nproc) or use your IDE of choice with CMake support
3. run build executables from the project root (as explained above)

windows

1. install any required dependencies below using winget:
   • lua can be installed with winget install devcom.lua
   • ffmpeg can be installed with winget install gyan.ffmpeg.shared
2. run cmake -S. -Bbuild && cmake --build build or use your IDE of choice with CMake support
3. run build executables from the project root (as explained above)

dll problem

on 64-bit systems, built executables dynamically link to FFTW and PortAudio, which are downloaded by the CMake build system at configure time into the build directory (or whatever you passed to -B when configuring). so if nothing happens when you run an audioviz executable from the terminal, and it returned a non-zero exit code, you need to append ;build to your PATH environment variable so that the libraries can be found. you can do this by running $env:PATH += ';build' in PowerShell, or set PATH=%PATH%;build in CMD. if you want this to persist for every PowerShell/CMD you open, add the absolute path to your build directory to your user environment variables.

macOS

thanks to CI, i discovered that the build process is the same as with linux. just use brew for package management. however i don't own a functional mac at the moment and have not tested the CI builds.

libraries/software used

• libaudioviz
  • FFTW3
  • ffmpeg, the standalone CLI program, part of the FFmpeg project
  • portaudio-pp - requires PortAudio (the C library, NOT the C++ binding)
  • SFML 3.0.1 - only supports X11 windows
  • tk-spline
• ttviz
  • argparse
  • ImGui-SFML
• luaviz
  • sol2 - requires Lua 5.x

project structure

audioviz
├── libaudioviz - core library
├── ttviz - first visualizer
├── luaviz - lua binding
├── lua - lua scripts calling the luaviz binding
│ ├── newviz.lua - newer style visualizer using luaviz
│ └── ttviz.lua - recreation of ttviz using luaviz
├── shaders - GLSL shaders used by audioviz::fx classes
└── tests - small test programs for various classes in libaudioviz

developer environment setup

i recommend using vscode as it integrates well with git with no effort. get the cmake tools extension and clangd to make development easier.

on windows: please use the mingw toolchain as it is the only toolchain i have compiled with, and honestly the easiest to setup and use. clangd might freak out about the standard headers being missing: to fix this, open clangd extension settings, and add the following argument:

--query-driver=C:\path\to\mingw\bin\g++.exe

todo list / goals

• figure out what to do with the shaders in order to make fully static binaries
• ✅️ ScopeDrawable class
  • extra: audio window customization independent of shape size
    • hint: use libswresample from ffmpeg
• 🔄 luaviz: the lua binding
  • 🔄 freshen up api for consumption
  • document the api
• 🔄 interactive gui (long term)
  • ✅️ integrate imgui-sfml into project
  • develop imgui window for each audioviz implementation
• add components/effects based on rhythm
  • involves knowing the tempo of the song
  • want a small translucent flash overlay that flashes to the beat of music
  • copy the osu! stars effect
• configurable opengl version and profile at runtime, along with compatible shaders
  • could lead to better performance on newer gpus