How to delete the embedded picture and add lyrics in flac?

Question

According to FLAC Documentation, pictures can be stored in flac audio format, but lyrics (maybe lrc, srt, or even ass/ssa) isn't mentioned in that documentation.

So, how to delete the embedded picture from flac and add lyrics into flac by software run in Linux platform?

(FFmpeg/avconv are preferred.)

Answer 1

Assuming that the embedded artwork is in a flac standard PICTURE block then:

metaflac --remove --block-type=PICTURE flacfile.flac

...ought to do it.

If the artwork is in the old, non-standard b64 encoded format, then:

metaflac --remove-tag=COVERART flacfile.flac

..ought to do it. No idea about the lyrics though.

Source

Relevant: http://linux.die.net/man/1/metaflac

Answer 2

You can use metaflac to add lyrics as well. Assume that the lyrics to "Tomorrow Never Knows" are in file "2-06.lyrics":

$ ls
'Grateful Dead -- 2-06 - Tomorrow Never Knows.flac'   2-06.lyrics

$ metaflac --remove-tag="Lyrics" "Grateful Dead -- 2-06 - Tomorrow Never Knows.flac"

$ metaflac --set-tag-from-file="Lyrics=2-06.lyrics" "Grateful Dead -- 2-06 - Tomorrow Never Knows.flac" 

$ metaflac --show-tag="Lyrics" "Grateful Dead -- 2-06 - Tomorrow Never Knows.flac" |more
Lyrics=Turn off your mind, relax
and float down stream
--More--

If you want to paste the lyrics into the terminal via STDIN (e.g., after a web search) followed by [CTRL-D]:

$ metaflac --set-tag="Lyrics=$(cat -)" "Grateful Dead -- 2-06 - Tomorrow Never Knows.flac"
[paste lyrics]
^D

NB: You can do this in ffmpeg too. To read from file 2-06.lyrics:

$ ffmpeg -y -i "Grateful Dead -- 2-06 - Tomorrow Never Knows.flac" -codec copy -metadata "Lyrics=$(cat lyrics)" "~Grateful Dead -- 2-06 - Tomorrow Never Knows.flac"
$ mv "~Grateful Dead -- 2-06 - Tomorrow Never Knows.flac" "Grateful Dead -- 2-06 - Tomorrow Never Knows.flac"

If you want to paste the lyrics into the terminal via STDIN followed by [CTRL-D]:

$ ffmpeg -y -i "Grateful Dead -- 2-06 - Tomorrow Never Knows.flac" -codec copy -metadata "Lyrics=$(cat -)" "~Grateful Dead -- 2-06 - Tomorrow Never Knows.flac" 
[paste lyrics]
^D
$ mv "~Grateful Dead -- 2-06 - Tomorrow Never Knows.flac" "Grateful Dead -- 2-06 - Tomorrow Never Knows.flac"  

If you wanted to tag an entire directory, you could put that in a for loop:

$ for f in *flac; do metaflac --remove-tag="Lyrics"; printf 'Paste lyrics for %s followed by Control-D:\n' "$f"; metaflac --set-tag="Lyrics=$(cat -)" "$f"; done