• Packages for Fedora: should be available here.

The source code of G'MIC is shared between several github repositories with public access. The code from these repositories are intended to be work-in-progress though, so we don't recommend using them to access the source code, if you just want to compile the various interfaces of the G'MIC project. Its is recommended to get the source code from the latest .tar.gz archive instead.

Here are the instructions to compile G'MIC on a fresh installation of Debian (or Ubuntu). It should not be much harder for other distros. First you need to install all the required tools and libraries:

Then, get the G'MIC source : allpassphase

You are now ready to compile the G'MIC interfaces: Phase Equalization (Linear Phase Design) The allpass phase

• gmic (command-line tool),
• gmic_gimp_qt (plug-in for GIMP),
• ZArt and
• libgmic (G'MIC C++ library).

Just pick your choice: An , conversely, features a perfectly flat magnitude

and go out for a long drink (the compilation takes time).

Note that compiling issues (compiler segfault) may happen with older versions of g++ (4.8.1 and 4.8.2). If you encounter this kind of errors, you probably have to disable the support of OpenMP in G'MIC to make it work, by compiling it with:

Also, please remember that the source code in the git repository is constantly under development and may be a bit unstable, so do not hesitate to report bugs if you encounter any.

Unlike standard high-pass, low-pass, or parametric EQ filters, an all-pass filter has a . It passes all frequencies with unity gain, meaning it does not alter the volume, boost the bass, or cut the treble of an incoming signal.

While they don't block frequencies, all-pass filters are invaluable in specialized tasks: A. Phase Equalization (Linear Phase Design)

The allpass phase has numerous applications in audio processing, including:

Sometimes, a kick drum might sound "thin" because its various frequency components aren't hitting at the exact same time. By applying subtle all-pass phase shifts, an engineer can align the low-end "thump" with the high-end "click," making the transient feel much tighter and more impactful. How it Works: The Technical Perspective

Diffusing sound to create the dense, natural decay found in large rooms [3].

An , conversely, features a perfectly flat magnitude response. It passes all frequencies with unity gain (

All-pass filters are usually grouped by how sharp and flexible their phase shifts are:

-domain, an all-pass filter is created by placing poles in the left-half of the

An all-pass filter has the following characteristics:

A common confusion arises between all-pass filters and Linear Phase EQs. Both manipulate phase, but in opposite ways.

The phase shifts from 0° at low frequencies to -180° (for a first-order filter) or -360° (for a second-order filter) as it passes the "center frequency."

In order to check if G'MIC works correctly on your system, you may want to execute the command and filter testing procedures. Assuming the CLI tool gmic is installed on your system, here is how to do it (on an Unix-flavored OS, adapt the instructions below for other OS):

These commands scan all G'MIC stdlib commands and G'MIC-Qt filters, and generate the images corresponding to the execution of these commands, with default parameters. Beware, this may take some time to complete!

G'MIC is an open-source software distributed under the CeCILL free software licenses (LGPL-like and/or
GPL-compatible). Copyrights (C) Since July 2008, David Tschumperlé - GREYC UMR CNRS 6072, Image Team.