FFmpeg adds its own metadata - encoder: Lavf58.20.100

Question

I've tried to apply the following advice on the flac files:

for x in *.flac; do
  ffmpeg -i "$x" -map 0:a -codec:a copy -map_metadata -1 clean_"$x";
done

But it seems, that ffmpeg though removes most metadata, it also adds its own fingerprint.

Why does it add this tag? What is the best way to get rid of it?

Answer 1

This answer deals with changing the encoder metadata.

I've just tried it, and using -metadata:g encoder_tool=" " does sets the encoder tag to a single space, but that seems to be the best we can get.

Using "" does stills adds the default FFMPEG encoder tag.

Answer 2

According to https://ffmpeg-user.ffmpeg.narkive.com/EAjF25dp/encoder-lavf it's displaying the version of libavformat for debug purposes.

Post by Leo Izen
  When I encode a video file it adds metadata that says
  Encoder: Lavf52.94.0
  I assume this means *L*ib*avf*ormat version 52.94.0. Why is this added? Is
  it to brag that the video file was muxed with libavformat, or does it have
  some productive reason?
It's not a "brag", it's primarily for debugging. If the file is
broken in some way, it's nice to know what version of libavformat
muxed it.
 
Jason