libavcodec-dev software package provides Development files for libavcodec, you can install in your Ubuntu 14.04 LTS (Trusty Tahr) by running the commands given below on the terminal,
$ sudo apt-get update $ sudo apt-get install libavcodec-dev
libavcodec-dev is installed in your system.
Make ensure the libavcodec-dev package were installed using the commands given below,
$ sudo dpkg-query -l | grep libavcodec-dev *
You will get with libavcodec-dev package name, version, architecture and description in a table
| Distro | Ubuntu 14 04 lts trusty tahr |
| Section | Library development |
| Package | libavcodec-dev |
| Version | 6:9.18-0ubuntu0.14.04.1 [amd64 |
| Description | Development files for libavcodec |
| Sub Section | libdevel |