How to install proprietary media codecs and font on Ubuntu

Ubuntu does not automatically install some multimedia media codecs and fonts due to licensing and legal reasons. Ubuntu considers DVD, MP3, Quicktime, Windows Media, and a few others as restricted formats you need to install explicitly. You will get the following Unable to play the file error if you try to play files without the proper codec installed.

You have the option to install all these codecs when installing Ubuntu by ticking the Install third-party software for graphics and Wi-Fi hardware and additional media formats checkbox in the Updates and other software panel. The installation will require an active internet connection because the packages are not included in the installer disc or ISO image.

If you missed the option, you can install them using apt. apt repository contains a meta package called ubuntu-restricted-extras that includes these codecs and other proprietary software such as Microsoft fonts.

1. Launch a terminal application.
2. Update apt's package application list from repository.

   $ sudo apt update
   [sudo] password for user: 
   Get:1 http://security.ubuntu.com/ubuntu focal-security InRelease [107 kB]
   Hit:2 http://jp.archive.ubuntu.com/ubuntu focal InRelease               
   Hit:3 http://jp.archive.ubuntu.com/ubuntu focal-updates InRelease
   Hit:4 http://jp.archive.ubuntu.com/ubuntu focal-backports InRelease
   Fetched 107 kB in 2s (61.1 kB/s)
   Reading package lists... Done
   Building dependency tree       
   Reading state information... Done
   All packages are up to date.

3. Install ubuntu-restricted-extras package using apt.

   $ sudo apt install --assume-yes ubuntu-restricted-extras
   Reading package lists... Done
   Building dependency tree       
   Reading state information... Done
   The following additional packages will be installed:
     cabextract chromium-codecs-ffmpeg-extra gstreamer1.0-libav
     gstreamer1.0-plugins-ugly gstreamer1.0-vaapi i965-va-driver
     intel-media-va-driver liba52-0.7.4 libaacs0 libaom0 libaribb24-0 libass9
     libavcodec-extra libavcodec-extra58 libavfilter7 libavformat58 libavutil56
     libbdplus0 libbluray2 libbs2b0 libchromaprint1 libcodec2-0.9 libdvdnav4
     libdvdread7 libfftw3-double3 libflite1 libgme0 libgsm1
     libgstreamer-plugins-bad1.0-0 libigdgmm11 liblilv-0-0 libmpeg2-4
     libmysofa1 libnorm1 libopencore-amrnb0 libopencore-amrwb0 libopenmpt0
     libpgm-5.2-0 libpostproc55 librubberband2 libserd-0-0 libshine3
     libsidplay1v5 libsnappy1v5 libsord-0-0 libsratom-0-0 libssh-gcrypt-4
     libswresample3 libswscale5 libva-drm2 libva-wayland2 libva-x11-2 libva2
     libvdpau1 libvidstab1.1 libvo-amrwbenc0 libx264-155 libx265-179
     libxvidcore4 libzmq5 libzvbi-common libzvbi0 mesa-va-drivers
     mesa-vdpau-drivers ocl-icd-libopencl1 ttf-mscorefonts-installer
     ubuntu-restricted-addons unrar va-driver-all vdpau-driver-all
   Suggested packages:
     gstreamer1.0-vaapi-doc i965-va-driver-shaders libbluray-bdj libdvdcss2
     libfftw3-bin libfftw3-dev serdi sidplay-base sordi opencl-icd
     libvdpau-va-gl1 nvidia-vdpau-driver nvidia-legacy-340xx-vdpau-driver
     nvidia-legacy-304xx-vdpau-driver
   Recommended packages:
     gstreamer1.0-fluendo-mp3
   The following NEW packages will be installed:
     cabextract chromium-codecs-ffmpeg-extra gstreamer1.0-libav
     gstreamer1.0-plugins-ugly gstreamer1.0-vaapi i965-va-driver
     intel-media-va-driver liba52-0.7.4 libaacs0 libaom0 libaribb24-0 libass9
     libavcodec-extra libavcodec-extra58 libavfilter7 libavformat58 libavutil56
     libbdplus0 libbluray2 libbs2b0 libchromaprint1 libcodec2-0.9 libdvdnav4
     libdvdread7 libfftw3-double3 libflite1 libgme0 libgsm1
     libgstreamer-plugins-bad1.0-0 libigdgmm11 liblilv-0-0 libmpeg2-4
     libmysofa1 libnorm1 libopencore-amrnb0 libopencore-amrwb0 libopenmpt0
     libpgm-5.2-0 libpostproc55 librubberband2 libserd-0-0 libshine3
     libsidplay1v5 libsnappy1v5 libsord-0-0 libsratom-0-0 libssh-gcrypt-4
     libswresample3 libswscale5 libva-drm2 libva-wayland2 libva-x11-2 libva2
     libvdpau1 libvidstab1.1 libvo-amrwbenc0 libx264-155 libx265-179
     libxvidcore4 libzmq5 libzvbi-common libzvbi0 mesa-va-drivers
     mesa-vdpau-drivers ocl-icd-libopencl1 ttf-mscorefonts-installer
     ubuntu-restricted-addons ubuntu-restricted-extras unrar va-driver-all
     vdpau-driver-all
   0 upgraded, 71 newly installed, 0 to remove and 0 not upgraded.
   Need to get 44.0 MB of archives.
   After this operation, 186 MB of additional disk space will be used.
   Do you want to continue? [Y/n]
   ##### snipped 

   Replace ubuntu-restricted-extras with kubuntu-restricted-extras, lubuntu-restricted-extras or xubuntu-restricted-extras accordingly if you're using the corresponding Ubuntu derivatives.

4. Read the End User License Agreement (EULA) for Microsoft TTF and click Ok.
5. Click Yes to accept the license agreement and proceed with installation.
6. Relaunch your application to start using the newly installed codec.