Edit: Due to the fact that this article is old, the installation instructions may not work anymore. In order to successfully install the latest version of Selene Media Encoder, please access the selene tag and open the latest article (the one on top).

The latest installation instructions for Selene Media Encoder
Hello Linux Geeksters. Selene Media Encoder is a video converting tool, with support for the most popular video and audio formats: OGG, OGV, MKV, MP4, WEBM, OPUS, AAC, FLAC, MP3 and WAV. The latest version available is Selene Media Encoder 2.4.3, which has been recently released.
In this article I will show you how to install Selene Media Encoder 2.4.3 on Ubuntu 14.04 Trusty Tahr, Ubuntu 14.04 Trusty Tahr, Ubuntu 13.10 Saucy Salamander, Ubuntu 12.04 Precise Pangolin, Linux Mint 17 Qiana, Linux Mint 16 Petra, Linux Mint 13 Maya, Elementary OS 0.3 Isis, Elementary OS 0.2 Luna, LXLE 14.04, Pinguy OS 14.04, Pinguy OS 12.04 and other Ubuntu derivatives.
Because it is available via PPA, installing Selene 2.3 on the listed Ubuntu, Linux Mint, LXLE, Pinguy OS and Elementary OS systems is easy. All you have to do is add the needed ppas, update the local repository index and install the selene package. Like this:
$ sudo add-apt-repository ppa:jon-severinsson/ffmpeg
$ sudo apt-add-repository ppa:teejee2008/ppa
$ sudo apt-get update
$ sudo apt-get install selene
Next, in order to be able to encode the AAC/MP4 format, you need the NeroAAC encoder:
$ wget http://ftp6.nero.com/tools/NeroAACCodec-1.5.1.zip
$ unzip -j NeroAACCodec-1.5.1.zip linux/neroAacEnc
$ sudo install -m 0755 neroAacEnc /usr/bin
$ sudo apt-get install gpac
Optional, to remove selene, do:
$ sudo apt-get remove selene