libavcodec-extra-56 software package provides Libav codec library (additional codecs), you can install in your Debian 8 (Jessie) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install libavcodec-extra-56
libavcodec-extra-56 is installed in your system.
Make ensure the libavcodec-extra-56 package were installed using the commands given below,
$ sudo dpkg-query -l | grep libavcodec-extra-56 *
You will get with libavcodec-extra-56 package name, version, architecture and description in a table
| Distro | Debian 8 jessie |
| Section | Libraries |
| Package | libavcodec-extra-56 |
| Version | 6:11.8-1~deb8u1 |
| Description | Libav codec library (additional codecs) |
| Sub Section | libs |