vsp

Simple, fast and lightweight spectrum visualiser made in C. It is a successor of vspectro in terms of performance and features. It grabs audio from a input device, analyses it through a sliding DFT and renders a logarithmic frequency spectrum with linear magnitude which you can study or just vibe to.

Features

• Magnitude can be zoomed in with ↓ key and out with ↑ key.
• Logarithmic horizontal (frequency bins) and linear vertical scaling (magnitude).
• Arbitarary capture device selection.
• Changable background and foreground colors.

Installation

Prerequisites

• https://libsdl.org/ (>=2.0)
• http://www.fftw.org/
• https://mesonbuild.com/

# on debian (or debian based distributions)
$ apt install libsdl2-dev libfftw3-dev

# on gentoo/funtoo
$ emerge media-libs/libsdl2 sci-libs/fftw

# on msys2 (mingw-w64)
$ pacman -S mingw-w64-SDL2 mingw-w64-fftw

On Windows it is less painful to install MSYS2 then compile it.

Compilation

Clone/download the repository and chdir into it ofcourse, then:

$ meson builddir -Doptimization=s -Dvsp:default_library=static
$ ninja -C builddir

It will produce an executable in builddir, which is the program.

Usage

$ ./builddir/vsp --help
Usage:

    -h, --help                show this help message and exit

Audio Options
    -d, --device=<int>        index of the capture device
    -r, --rate=<int>          desired samplerate of audio
    -s, --size=<int>          number of samples to analyse at once
    --list-devices            list available devices
    --audio-bufsize=<int>     size of the SDL audio buffer
    --max-volume=<flt>        initial maximum displayed volume
    

Display Options
    --fg-color=<str>          foreground color of the visualisation window
    --bg-color=<str>          background color of the visualisation window
    --width=<int>             initial width of the visualisation window
    --height=<int>            initial height of the visualisation window

--fg-color and --bg-color is in the hex-color format (optionally prefixed with #).

--list-devices shows what devices are for capturing with their indices.

list of capture devices:
    [index]    [name]
         0      Mic in at front panel (Pink) (Realtek High Definition Audio)
         1      Stereo Mix (Realtek High Definition Audio)

If to choose a specific device than default, pass the any of the indices with -d. If passed index is not in that list, it falls back to default.

Technical details

• No windowing function is applied on the incoming samples, spectral leakage might occur.
• Frequency spectrum starts at 20hZ.