Cross-platform Audio Visualizer

by Karl Stavestrand

Demo video

• What it is
• Installing
  • From Source
  • Package managers
• Capturing audio
  • Pulseaudio
  • Pipewire
  • ALSA
  • MPD
  • Sndio
  • OSS
  • JACK
  • squeezelite
  • macOS
  • Windows
• Running via ssh
• Troubleshooting
• Usage
  • Controls
• Configuration
• Using cava in other applications
  • cavacore
  • Raw Output
• Contribution

Cava is a bar spectrum audio visualizer for terminal or desktop (SDL).

works on:

• Linux
• FreeBSD
• macOS
• Windows

This program is not intended for scientific use. It's written to look responsive and aesthetic when used to visualize music.

Required components:

• FFTW
• libtool
• automake
• autoconf-archive (needed for setting up OpenGL)
• pkgconf
• build-essentials
• iniparser

Recomended components:

The development lib of one of these audio frameworks, depending on your distro:

• ALSA
• Pulseaudio
• Pipewire
• Portaudio
• Sndio
• JACK

Optional components:

• SDL2 dev files
• ncursesw dev files (bundled in ncurses in arch)

Only FFTW, iniparser and the build tools are actually required for CAVA to compile, but this will only give you the ability to read from fifo files. To capture audio directlty from your system pipewire, pulseaudio, alsa, sndio, jack or portaudio dev files are required (depending on what audio system you are using).

Ncurses can be used as an alternative output method if you have issues with the default one. But it is not required.

All the requirements can be installed easily in all major distros:

FreeBSD

pkg install autoconf autoconf-archive automake fftw3 iniparser jackit libglvnd libtool pkgconf psftools sdl2 sndio

Additionally, run these commands on FreeBSD before building:

export CFLAGS="-I/usr/local/include"
export LDFLAGS="-L/usr/local/lib"

Debian/Ubuntu:

sudo apt install build-essential libfftw3-dev libasound2-dev libpulse-dev libtool automake autoconf-archive libiniparser-dev libsdl2-2.0-0 libsdl2-dev libpipewire-0.3-dev libjack-jackd2-dev pkgconf

ArchLinux:

pacman -S base-devel fftw alsa-lib iniparser pulseaudio autoconf-archive pkgconf

openSUSE:

zypper install alsa-devel fftw3-devel libpulse-devel libtool autoconf-archive pkgconf

Fedora:

dnf install alsa-lib-devel fftw3-devel pulseaudio-libs-devel libtool autoconf-archive iniparser-devel pkgconf

macOS:

First install homebrew if you have't already:

/usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

Then install prerequisites:

brew install fftw libtool automake autoconf-archive pkgconf portaudio iniparser

The installation location for Homebrew packages is different between Intel Macs and Apple Silicon Macs. As such, the commands will be a little bit different. You can find out which type you have here

For both machines, run these commands to fix macOS not finding libtool:

export LIBTOOL=`which glibtool`
export LIBTOOLIZE=`which glibtoolize`
ln -s `which glibtoolize` /usr/local/bin/libtoolize

Note that the file name may be a little bit different depending on the versions, but the directory should be the same.

Additionally, run these commands on Apple Silicon Macs so that ./configure can find the Homebrew packages:

export LDFLAGS="-L/opt/homebrew/lib"
export CPPFLAGS="-I/opt/homebrew/include"

Intel Mac instructions tested on macOS Big Sur.

Apple Silicon instructions tested on macOS Ventura.

Windows:

see separate readme in cava_win folder.

First of all clone this repo and cd in to it, then run:

./autogen.sh
./configure
make

If you have a recommended component installed, but do not wish to use it (perhaps if building a binary on one machine to be used on another), then the corresponding feature can be disabled during configuration (see configure --help for details).

For windows there is a VS solution file in the cava_win folder.

Install cava to default /usr/local:

make install

Or you can change PREFIX, for example:

./configure --prefix=PREFIX

make uninstall

All distro specific instalation sources might be out of date. Please check version before reporting any issues here.

pkg install cava

Tumbleweed users have cava in their repo. They can just use:

zypper in cava

Leap users need to add the multimedia:apps repository first:

zypper ar -f obs://multimedia:apps/openSUSE_Leap_42.2 multimedia

If you use another version just replace openSUSE_Leap_42.2 with openSUSE_13.2, adjust it to your version.

Cava is available in Fedora 26 and later. You can install Cava by running:

dnf install cava

Cava is in AUR.

pacaur -S cava

sudo apt install cava

Harshal Sheth has added CAVA to his PPA, it can be installed with:

add-apt-repository ppa:hsheth2/ppa
apt update
apt install cava

cava is in homebrew.

brew install cava

Just make sure you have installed pulseaudio dev files and that cava has been built with pulseaudio support (it should be automatically if the dev files are found).

If you're lucky all you have to do is to run cava.

If nothing happens you might have to use a different source than the default. The default might also be your microphone. Look at the config file for help.

Set

method = pipewire

The default source is auto and will most likely be your currently selected output. If you run wireplumber you can use wpctl to get the object.path or object.serial of the desired device to visualize.

e.g.

source = alsa:pcm:3:front:3:playback

Set

method = alsa

in the config file.

ALSA can be difficult because there is no native way to grab audio from an output. If you want to capture audio straight fom the output (not just mic or line-in), you must create an ALSA loopback interface, then output the audio simultaneously to both the loopback and your normal interface.

To create a loopback interface simply run:

sudo modprobe snd_aloop

Hopefully your aplay -l should now contain a loopback interface.

To make it persistent across boot add the line snd-aloop to "/etc/modules". To keep it from being loaded as the first soundcard add the line options snd-aloop index=1 to "/etc/modprobe.d/alsa-base.conf", this will load it at '1'. You can replace '1' with whatever makes most sense in your audio setup.

Playing the audio through your Loopback interface makes it possible for cava to capture it, but there will be no sound in your speakers. In order to play audio on the loopback interface and your actual interface you must make use of the ALSA multi channel.

Look at the included example file example_files/etc/asound.conf on how to use the multi channel. I was able to make this work with a HDA Intel PCH sound card, but I had no luck with the an USB DAC.

Read more about the ALSA method here.

If you are having problems with the alsa method on Rasberry PI, try enabling mmap by adding the following line to /boot/config.txt and reboot:

dtoverlay=i2s-mmap

@reluekiss, was able to make cava work with dmix. Check out the example config in example_files/etc/asound_dmix.conf and issue 534.

Add these lines in mpd:

audio_output {
    type                    "fifo"
    name                    "my_fifo"
    path                    "/tmp/mpd.fifo"
    format                  "44100:16:2"
}

Uncomment and change input method to fifo in the config file.

The path of the fifo can be specified with the source parameter.

I had some trouble with sync (the visualizer was ahead of the sound). Reducing the ALSA buffer in mpd fixed it:

audio_output {
        type            "alsa"
        name            "My ALSA"
        buffer_time     "50000"   # (50ms); default is 500000 microseconds (0.5s)
}

Set

method = sndio

Sndio is the audio framework used on OpenBSD, but it's also available on FreeBSD, NetBSD and Linux. So far this is only tested on FreeBSD, but it's probably very similar on other operating systems. The following example demonstrates how to setup CAVA for sndio on FreeBSD (please consult the OSS section for a deeper explanation of the various pcmX sound devices and the corresponding /dev/dspX audio devices in this example).

$ cat /dev/sndstat
Installed devices:
pcm0: <Realtek ALC1220 (Rear Analog)> (play/rec) default
pcm1: <Realtek ALC1220 (Front Analog Mic)> (rec)
pcm2: <USB audio> (play/rec)
No devices installed from userspace.

Sndio operates on device descriptors. In general for every /dev/dspX audio device there is a corresponding rsnd/X sndio raw device descriptor. In this example there are rsnd/0, rsnd/1 and rsnd/2 (they are not listed in /dev, sndio uses these descriptors to access the corresponding audio devices internally). Sndio also handles the implicit default device descriptor, which acts like a symlink to the raw device descriptor corresponding to the default audio device /dev/dsp. In this example it acts like a symlink to rsnd/0 because the default audio device /dev/dsp symlinks to /dev/dsp0. Sndio also evaluates the environment variables AUDIODEVICE and AUDIORECDEVICE. If one of these is set (AUDIORECDEVICE overrides AUDIODEVICE if both are set) and a sndio-aware program tries to open the default device descriptor or an unspecified device descriptor, then the program will use the device descriptor specified in the environment variable.

Now in order to visualize the mic input in CAVA, the source value in the configuration file must be set to the corresponding audio descriptor:

source = default    # default; symlink to rsnd/0 in this example; AUDIORECDEVICE and AUDIODEVICE evaluation
source =            # unspecified device descriptor; same as default above
source = rsnd/0     # for the pcm0 mic on the rear
source = rsnd/1     # for the pcm1 mic on the front
source = rsnd/2     # for the pcm2 mic on the USB headset

With source = default one can switch the visualization on the commandline without changing the configuration file again:

$ AUDIODEVICE=rsnd/0 cava
$ AUDIODEVICE=rsnd/1 cava
$ AUDIODEVICE=rsnd/2 cava

Sndio can't record the played back audio with just the raw device descriptors, i.e. the sounds from a music player or a browser which play on the external stereo speakers through rsnd/0 are not visualized in CAVA. For this to work the sndio server has to be started and a monitoring sub-device has to be created. The following example shows how to start the server and create a monitoring sub-device snd/0 from rsnd/0 and then start CAVA with AUDIODEVICE pointing to the new monitoring sub-device:

$ sndiod -f rsnd/0 -m play,mon
$ AUDIODEVICE=snd/0 cava

Switch between the speakers and the USB headset:

$ sndiod -f rsnd/2 -m play,mon -s usb -f rsnd/0 -m play,mon -s speakers
$ AUDIODEVICE=snd/usb cava
$ AUDIODEVICE=snd/speakers cava

Consult the manpage sndiod(8) for further information regarding configuration and startup of a sndio server.

Set

method = oss

The audio system used on FreeBSD is the Open Sound System (OSS). The following example demonstrates how to setup CAVA for OSS on FreeBSD:

$ cat /dev/sndstat
Installed devices:
pcm0: <Realtek ALC1220 (Rear Analog)> (play/rec) default
pcm1: <Realtek ALC1220 (Front Analog Mic)> (rec)
pcm2: <USB audio> (play/rec)
No devices installed from userspace.

The system has three pcm sound devices, pcm0, pcm1 and pcm2. pcm0 corresponds to the analog output jack on the rear, in which external stereo speakers are plugged in, and the analog input jack, in which one could plug in a microphone. Because it encapsulates both, output and input, it is marked as play/rec. It is also set as the default sound device. pcm1 corresponds to another analog input jack for a mic on the front side and is marked rec. A USB headset with an integrated mic is plugged in an USB port and the system has created the pcm2 sound device with play/rec capabilities for it.

In general for every pcmX device there is a corresponding /dev/dspX audio device. In this example there are /dev/dsp0, /dev/dsp1 and /dev/dsp2 (the system creates them when needed, they are not listed via ls /dev if they are currently not in use). The system also creates an implicit /dev/dsp, which acts like a symlink to the default audio device, in this example to /dev/dsp0.

Now in order to visualize the mic input in CAVA, the source value in the configuration file must be set to the corresponding audio device:

source = /dev/dsp     # default; symlink to /dev/dsp0 in this example
source = /dev/dsp0    # for the pcm0 mic on the rear
source = /dev/dsp1    # for the pcm1 mic on the front
source = /dev/dsp2    # for the pcm2 mic on the USB headset

OSS can't record the outgoing audio on its own, i.e. the sounds from a music player or a browser which play on the external stereo speakers through /dev/dsp0 are not visualized in CAVA. A solution is to use Virtual OSS. It can create virtual audio devices from existing audio devices, in particular it can create a loopback audio device from /dev/dsp0 and from which the played back audio can be fed into CAVA:

$ doas pkg install virtual_oss
$ doas virtual_oss -r44100 -b16 -c2 -s4ms -O /dev/dsp0 -R /dev/null -T /dev/sndstat -l dsp.cava

$ cat /dev/sndstat
Installed devices:
pcm0: <Realtek ALC1220 (Rear Analog)> (play/rec) default
pcm1: <Realtek ALC1220 (Front Analog Mic)> (rec)
pcm2: <USB audio> (play/rec)
Installed devices from userspace:
dsp.cava: <Virtual OSS> (play/rec)

It created a virtual loopback device /dev/dsp.cava from /dev/dsp0. Now the audio is visualized in CAVA with source = /dev/dsp.cava in the configuration file. The playback program must have a configuration to use the /dev/dsp.cava device. For programs where this is not possible, e.g. which always use /dev/dsp, replace -l dsp.cava with -l dsp. Virtual OSS can be configured and started as a service on FreeBSD.

Set

method = jack

The JACK Audio Connection Kit (JACK) is a professional sound server API which is available on several operating systems, e.g. FreeBSD and Linux.

CAVA is a JACK client with the base client name cava and adheres to the standard server start and stop behaviour, i.e. CAVA starts a JACK server if none is already running and the environment variable JACK_START_SERVER is defined, in which case the server also stops when all clients have exited. The source in the CAVA configuration file specifies the name of the JACK server to which CAVA tries to connect to. The default value is default, which is also the default JACK server name. The value can be empty, in which case it implies default. Therefore the following three entries are equivalent:

; source = default
source = default
source =

One exception is the combination of an empty source entry and the environment variable JACK_DEFAULT_SERVER. If the environment variable is defined, e.g. export JACK_DEFAULT_SERVER=foo, then the following entries are equivalent:

source = foo
source =

Consult the manpage jackd(1) for further information regarding configuration and startup of a JACK server.

CAVA creates terminal audio-typed (so no MIDI support) input ports. These ports can connect to output ports of other JACK clients, e.g. connect to the output ports of a music player and CAVA will visualize the music. Currently CAVA supports up to two input ports, i.e. it supports mono and stereo. The number of input ports can be controlled via the channels option in the input section of the configuration file:

channels = 1    # one input port, mono
channels = 2    # two input ports, stereo (default)

The port's short name is simply M for mono, and L and R for stereo. The full name of the input port according to the base client name is cava:M for mono, and cava:L and cava:R for stereo.

The option autoconnect controls the connection strategy for CAVA's ports to other client's ports:

autoconnect = 0    # don't connect to other ports automatically
autoconnect = 1    # only connect to other ports during startup
autoconnect = 2    # reconnect to new ports regularly (default)

The automatic connection strategies scan the physical terminal input-ports, i.e. the real audio device which actually outputs the sound, and applies the same connections to CAVA's ports. In this way CAVA visualizes the played back audio from JACK clients by default.

In order to control and manage the connection between CAVA's ports and ports of other client programs, there are connection management programs for JACK. Some well known connection managers with a graphical user interface are QjackCtl and Cadence. The JACK package itself often comes with CLI tools. Depending on the operating system it could be necessary to install them separately, e.g. on FreeBSD:

$ doas pkg install jack-example-tools

Among the tools are the programs jack_lsp and jack_connect. These two tools are enough to list and connect ports on the commandline. The following example demonstrates how to setup connections with these tools:

$ jack_lsp
system:capture_1
system:capture_2
system:playback_1
system:playback_2
cava:L
moc:output0
moc:output1
cava:R

This listing shows all full port names that are currently available. These correspond to two external JACK clients, cava and moc, and one internal JACK client system. The types and current active connections between the ports can be listed with the -p and -c switches for jack_lsp. In order to connect the ports of CAVA and MOC, jack_connect is used:

$ jack_connect cava:L moc:output0
$ jack_connect cava:R moc:output1

Now CAVA visualizes the outgoing audio from MOC.

squeezelite is one of several software clients available for the Logitech Media Server. Squeezelite can export its audio data as shared memory, which is what this input module uses. Just adapt your config:

method = shmem
source = /squeezelite-AA:BB:CC:DD:EE:FF

where AA:BB:CC:DD:EE:FF is squeezelite's MAC address (check the LMS Web GUI (Settings>Information) if unsure). Note: squeezelite must be started with the -v flag to enable visualizer support.

Note: Cava doesn't render correctly within the default macOS terminal. In order to achieve an optimal display, install Kitty. Beware that you may run in to the issue presented in #109; however, it can be resolved with this.

Background Music

Install Background Music which provides a loopback interface automatically. Once installed and running just edit your config to use this interface with portaudio:

method = portaudio
source = "Background Music"

Sound Flower

Soundflower also works to create a loopback interface. Use Audio MIDI Setup to configure a virtual interface that outputs audio to both your speakers and the loopback interface, following this recipe. By creating a multi-output device you lose the ability to control the volume on your keyboard. Because of this, we recommend the Background Music app which still gives you keyboard controls.

Then edit your config to use this interface with portaudio:

method = portaudio
source = "Soundflower (2ch)"

Should capture the audio from the default output device automatically.

To run via ssh to an external monitor, redirect output to /dev/console:

 ~# ./cava  <> /dev/console >&0 2>&1

exit with ctrl+z then run 'bg' to keep it running after you log out.

(You must be root to redirect to console. Simple sudo is not enough: Run sudo su first.)

Most likley issue #399. Locale settings need to be set correctly in order for cava to work.

This is a known issue with pipewire. Try the workaround described here

This is either an issue with the font, or line spacing being enabled in the terminal emulator. Try to change font or disable line spacing.

Since the graphics are simply based on characters, try decreasing the font size.

Some terminal emulators are just slow. Cava will look best in a GPU based terminal like kitty or alacritty. You can also try to increase the font size

If you run cava in a TTY (like ctrl+alt+F2) the program will change the font to the included cava.psf (actually a slightly modified "unifont").

In console fonts it seems that only 256 Unicode characters are supported, probably because they are bitmap fonts. I could not find a font with Unicode characters 2581-2587 (the 1/8 - 7/8 blocks used on the top of each bar to increase resolution).

So in cava.psf, the characters 1-7 are actually replaced by Unicode characters 2581-2587. When cava exits, it changes the font back. If cava exits abnormally and you notice that 1-7 are replaced by partial blocks, just change the font with setfont.

Actually, setfont is supposed to return the default font, but this usually isn't set. I haven't found another way to get the current font. So cava sets the font to "Lat2-Fixed16" when interrupted. All major distros should have it. It will revert to your default font at reboot.

Konsole simply does not support this. #194

Usage : cava [options]
Visualize audio input in terminal. 

Options:
	    -p          path to config file
	    -v          print version

Exit with ctrl+c or q.

If cava quits unexpectedly or is force killed, echo must be turned on manually with stty -echo.

As of version 0.4.0 all options are done in the config file, no more command-line arguments!

By default a configuration file is created upon first launch in $XDG_CONFIG_HOME/cava/config or $HOME/.config/cava/config, but cava can also be made to use a different file with the -p option.

Sending cava a SIGUSR1 signal, will force cava to reload its configuration file. Thus, it behaves as if the user pressed r in the terminal. One might send a SIGUSR1 signal using pkill or killall. For example:

$ pkill -USR1 cava

Similarly, sending cava a SIGUSR2 signal will only reload the colors from the configuration file, which is the same as pressing c in the terminal. This is slightly faster than reloading the entire config as the audio processing does not need to reinitialize.

$ pkill -USR2 cava

Examples on how the equalizer works:

[eq]
1=0
2=1
3=0
4=1
5=0

[eq]
1=2
2=2
3=1
4=1
5=0.5

The core processing engine in cava has been split into a separate library cavacore. See CAVACORE.md for details.

You can also use Cava's output for other programs by using raw output mode, which will write bar data to STDOUT that can be piped into other processes. More information on this option is documented in the example config file.

A useful starting point example script written in python that consumes raw data can be found here.

Please read CONTRIBUTING.md before opening a pull request.

Thanks to:

• CelestialWalrus
• anko
• livibetter

for major contributions in the early development of this project.

Also thanks to dpayne for figuring out how to find the pulseaudio default sink name.