ffmpeg is the defacto tool for getting audio information from a file/URL. But I am a bit stumped on how to get the size of the ID3v2 tags for the same.
Example of what information ffmpeg gives when we use ffprobe:
Input #0, mp3, from 'FILENAME':
Metadata:
encoder : Lavf58.29.100
Duration: 00:04:39.14, start: 0.000000, bitrate: 320 kb/s
Stream #0:0: Audio: mp3, 48000 Hz, stereo, fltp, 320 kb/s
The metadata values are given but what would be the way to calculate the size of this in bytes?
Search the stderr output of ffmpeg -i file.mp3 -v debug
for a line of the form
id3v2 ver:4 flags:00 len:137