Jack Graph

Jack Graph is a graphical connection manager for the JACK Audio Connection Kit and ALSA MIDI. It shows the audio and MIDI ports of running applications and hardware as an interactive graph, and you connect and disconnect them by dragging cables.

Jack Graph also manages the JACK server itself. You can start and stop JACK, and choose your audio interface, sample rate, buffer size and MIDI driver, from inside the application. No external tools or system services are required.

Version 2 draws its own interface with X11, Cairo and FreeType. There is no GTK, GLib or Pango, and no widget toolkit of any kind.

Features

Visual graph

Drag from an output port (right side of a box) to an input port (left side) to connect.
Right-click a cable to disconnect it.
Drag a box to move it; drag empty canvas to pan; the mouse wheel zooms about the pointer.
Stereo pairs (out / outR) are kept next to each other.
Boxes stay where you put them when JACK clients come and go. Refresh lays the graph out again from scratch.
Toolbar: Refresh, Zoom −, Zoom +, Zoom 1:1, Fit, JACK Settings, About.

JACK

Start and stop the JACK server from JACK Settings. Starting and stopping never freeze the window.
If jackd fails to start (for example, the device is busy or doesn't support the sample rate), jackd's own explanation is shown in the settings window.
Apply Live changes frames/period on the running server without a restart.
The graph updates live as ports appear and disappear. If the server stops or crashes, Jack Graph notices and reconnects when it comes back.
The status bar shows buffer size, sample rate and xrun count.
jackd keeps running after you close Jack Graph. The next time you open it, Jack Graph picks the server up again and can still stop it.

ALSA MIDI

While JACK is not running, the ALSA sequencer's MIDI ports are shown instead. You can connect and disconnect them the same way; this is what aconnect does.
The view updates live when a MIDI device is plugged in or a connection is made elsewhere.

Settings

The Interface dropdown shows device names (for example HDA Intel PCH - ALC897 Analog) and stores stable ALSA ids (hw:CARD=PCH), so the choice survives plugging in a USB interface.
Options: Realtime, and 16-bit samples (jackd's ALSA -S, "shorts").
MIDI driver: None, ALSA sequencer (-X seq) or ALSA raw MIDI (-X raw).
Settings and the window size are saved in ~/.config/jack-graph/config.

Installation

From a release tarball

Download the tarball for your machine. Use jack-graph-<version>-linux-x86_64.tar.gz for a PC, or jack-graph-<version>-linux-aarch64.tar.gz for a Raspberry Pi or another 64-bit ARM board. Then extract it and run the installer:

tar -xf jack-graph-<version>-linux-<arch>.tar.gz
cd jack-graph
sudo ./install.sh

The installer:

Installs the runtime dependencies with your package manager (see the table below).
On Debian, Devuan and Ubuntu, holds qjackctl with apt-mark hold, so it isn't pulled in as a recommendation of jackd2. Jack Graph replaces it.
Adds your user to the audio group, which JACK needs for realtime priority. Log out and back in after installing so the group change takes effect.
Installs jack-graph to /usr/local/bin, its fonts to /usr/local/share/jack-graph/fonts, and the desktop entry to /usr/share/applications.

The tarball contains a prebuilt binary and the full source. If the prebuilt binary is for a different architecture, or can't find its libraries on your system, the installer builds from the bundled source instead. Pass --from-source to always build from source, and --no-deps to skip installing packages.

Runtime dependencies

Distro	Packages
Debian / Devuan / Ubuntu	`jackd2` `libjack-jackd2-0` `libasound2` `libcairo2` `libfreetype6` `libx11-6`
Arch / Artix	`jack2` `alsa-lib` `cairo` `freetype2` `libx11`
Void	`jack` `alsa-lib` `cairo` `freetype` `libX11`
Fedora	`jack-audio-connection-kit` `alsa-lib` `cairo` `freetype` `libX11`

From a .deb (Debian 12 and later, Devuan, Raspberry Pi OS)

sudo apt install --no-install-recommends ./jack-graph_<version>_<arch>.deb

Use --no-install-recommends, because jackd2 otherwise pulls in qjackctl. Unlike install.sh, the package doesn't add you to the audio group. To do that yourself:

sudo usermod -aG audio "$USER"

Uninstall

sudo ./uninstall.sh

This removes the binary, the fonts and the desktop entry, and releases the apt-mark hold on qjackctl if it was set. Your settings and the runtime dependencies are left in place.

Usage

Open Jack Graph from your application menu, or run jack-graph in a terminal.
Press JACK Settings.
Choose your audio interface, sample rate, frames/period and periods/buffer.
Press Start. The graph fills in as soon as the server is up.
Connect ports: drag from an output on the right of a box to an input on the left of another.
Disconnect: right-click a cable.
To change the buffer size while JACK is running, pick a new Frames/Period and press Apply Live. Everything else needs Stop then Start.

Command line:

jack-graph [--scale N] [--version]
  --scale N   draw at N times the normal size (HiDPI); also read from $JACK_GRAPH_SCALE

jackd's output goes to $XDG_RUNTIME_DIR/jack-graph/jackd.log, or to ~/.cache/jack-graph/ when XDG_RUNTIME_DIR isn't set.

Building from source

Build dependencies

Debian / Devuan / Ubuntu:

sudo apt install g++ make pkg-config libjack-jackd2-dev libasound2-dev libcairo2-dev libfreetype-dev libx11-dev

Arch / Artix:

sudo pacman -S base-devel jack2 alsa-lib cairo freetype2 libx11

Void:

sudo xbps-install gcc make pkg-config jack-devel alsa-lib-devel cairo-devel freetype-devel libX11-devel

Fedora:

sudo dnf install gcc-c++ make pkgconf jack-audio-connection-kit-devel alsa-lib-devel cairo-devel freetype-devel libX11-devel

Build and run

make
./jack-graph          # runs from the build tree; finds its fonts in ./resources
sudo make install     # or: PREFIX=/usr, DESTDIR=... for packaging

make also builds tools/uirender, a headless layout check. It draws every window with the bundled fonts and fails if any label overflows its slot or uses a character the fonts lack. It needs no X server and no sound card:

./tools/uirender --out ui

Releases

The version lives in VERSION. The Makefile, --version, the About box, the tarball name and the .deb all read it. Bump it when cutting a release.

x86_64 is built by hand on a Debian 12 machine, to keep the glibc floor at 2.36:

./release-tarball.sh          # jack-graph-<version>-linux-x86_64.tar.gz
packaging/build-deb.sh        # jack-graph_<version>_amd64.deb

aarch64 is built by the Linux aarch64 GitHub Actions workflow, on every push, in a debian:12 container on an arm64 runner. Before uploading anything it checks that:
- the build is warning-free;
- the binary is an aarch64 ELF;
- it needs no glibc symbol newer than 2.36;
- it passes the dependency allowlist (scripts/check-deps.sh);
- it passes the uirender audit;
- the bundled source builds on its own;
- the tarball and .deb names match VERSION.
The tarball, the arm64 .deb and the audit's images are uploaded as run artifacts, and attached to a release by hand once tested on a board.

Technologies

Component	Technology
Window and input	Xlib
Drawing	Cairo
Text	FreeType, with bundled Roboto and Michroma fonts
Audio server	JACK (jackd2)
MIDI	ALSA sequencer
Language	C++17
Build system	GNU Make

Project structure

jack-graph/
├── src/
│   ├── main.cpp                   # Entry point: the windows and the event loop (the only X11 user here)
│   ├── app.h/cpp                  # The application: JACK, ALSA, config, server start/stop, panels
│   ├── graphpanel.h/cpp           # The graph canvas: layout, pan, zoom, drag to connect
│   ├── settingspanel.h/cpp        # The JACK Settings window
│   ├── chrome.h/cpp               # Toolbar, status line, About card
│   ├── graphgeometry.h            # Every size and position in the windows
│   ├── JackClient.hpp/cpp         # JACK client: ports, connections, callbacks
│   ├── JackServerControl.hpp/cpp  # Starts and stops jackd (fork/exec), lists ALSA devices
│   ├── AlsaClient.hpp/cpp         # ALSA sequencer: MIDI ports, subscriptions, announcements
│   ├── Config.hpp/cpp             # ~/.config/jack-graph/config
│   ├── Node / Connection / ClientBox  # The graph's data model
│   ├── gfx/                       # Cairo + FreeType drawing and widgets (no X11)
│   └── platform/                  # X11 window, event loop, self-pipe, paths
├── tools/uirender.cpp             # Headless layout audit
├── resources/                     # Bundled fonts (with licences) and the desktop entry
├── packaging/                     # install.sh, uninstall.sh, build-deb.sh
├── scripts/check-deps.sh          # Linked-library allowlist
├── release-tarball.sh             # Builds the release tarball
├── VERSION
└── LICENSE                        # GPL-2.0

License

This project is licensed under the GNU General Public License v2.0. See LICENSE for details. The bundled fonts are under their own licences: Roboto (Apache-2.0) and Michroma (OFL-1.1), included in resources/fonts/.

Navigation Menu

Repository navigation

About

Repository files navigation

Jack Graph

Features

Visual graph

JACK

ALSA MIDI

Settings

Installation

From a release tarball

Runtime dependencies

From a .deb (Debian 12 and later, Devuan, Raspberry Pi OS)

Uninstall

Usage

Building from source

Build dependencies

Build and run

Releases

Technologies

Project structure

License

About

Releases

Packages

Contributors

Languages

Name		Name	Last commit message	Last commit date
.github/workflows		.github/workflows
packaging		packaging
resources		resources
scripts		scripts
src		src
tools		tools
.gitignore		.gitignore
LICENSE		LICENSE
Makefile		Makefile
README.md		README.md
VERSION		VERSION
release-tarball.sh		release-tarball.sh

Latest commit

History

Folders and files

Repository files navigation

Jack Graph

Features

Visual graph

JACK

ALSA MIDI

Settings

Installation

From a release tarball

Runtime dependencies

From a .deb (Debian 12 and later, Devuan, Raspberry Pi OS)

Uninstall

Usage

Building from source

Build dependencies

Build and run

Releases

Technologies

Project structure

License

About

Resources

Stars

Watchers

Forks

Releases

Packages

Contributors

Languages