How to extract/inject ID3 tags via bash?

Open the terminal and type:

sudo apt-get install eyeD3  

eyeD3 is a terminal program to display and manipulate id3-tags on the command-line.
A command-line editor to add/edit/remove ID3-tags on mp3 files. It supports version 1.0,1.1,2.3 and 2.4 of the ID3 standard. Additionally it displays several information about the file such as length and bitrate from an MP3 file.

A web search using the search terms bash script eyeD3 will bring up examples of bash scripts using eyeD3 designed to do several different kinds of tasks such as reading mp3 tags, writing mp3 tags, read/write ID3V1 (ID3 version 1) tags, and read/write ID3V2 (ID3 version 2) tags.