MPTag provides a wrapper around the taglib-sharp.dll which is freely available and allows you to read and write multimedia tag information (http://taglib-sharp.sourcearchive.com/).
Simply unzip the package (you may want to right-click the zip file first and open its property dialog to remove download restrictions automatically applied by IE). Next, you can import the module into PowerShell:
Import-Module c:\somepath\mptag
This will automatically load the dll and provides you with the function Get-MediaInfo. It will return an object with media information for your media files. Call it like this:
$m = Get-MediaInfo c:\folder\video_or_music_file.xyz
Media information contained in $m now gets you all the info you want:
$m
$m.Tag
$m.Properties
$m.Properties.Codecs
You can even change information in $m and write it back using $m.Save() to change multimedia file attributes.