New in Airtime 2.4 is unofficial support for AAC+. Due to legal distribution issues, we cannot make this an out-of-box working experience, however full detailed instructions are provided in this wiki article.
You will need to download and compile a package first. This is very simple, and step-by-step instructions will be provided here. Before we start, you will need some packages. From the terminal, type
sudo apt-get install build-essential
The next step is to download the latest version of fdk-aac here. At the time of this writing, the version is 0.1.1.
Once downloaded, extract the tar ball. From the terminal, type
tar xzf fdk-aac-0.1.1.tar.gz
Now cd into the newly created directory
Now enter the following commands:
./configure --prefix /usr make sudo make install
Now that we have the appropriate packages installed, the next step is to build Liquidsoap with AAC+ enabled. Detailed compilation and installation instructions are available here: Building Liquidsoap from Source
Now that Liquidsoap has been compiled with AAC+ support, we have one more final step - enable the ability to select these output types in the Web UI.
To enable AAC+ run the following:
sudo -u postgres psql -c "update cc_pref set valstr = valstr||', fdkaac' where keystr = 'stream_type'" airtime
To revert the above command, simply run:
sudo -u postgres psql -c "update cc_pref set valstr = 'ogg, mp3, opus, aac' where keystr = 'stream_type'" airtime
Your Airtime install should now fully support AAC+ output.