Given this file I am having mixed results writing metadata. For example this command
ffmpeg -i confetti.mp4 -c copy -f adts - | ffmpeg -i - -c copy -bsf aac_adtstoasc -movflags faststart \ -metadata title=Confetti good.m4a
Will generate an M4A file that plays correctly with metadata that is recognized. However this command
ffmpeg -i confetti.mp4 -c copy -vn -movflags faststart \ -metadata title=Confetti bad.m4a
Generates a file that plays correctly, but my player does not recognize the
metadata. Note I also tried adding
-bsf aac_adtstoasc to the bad command to no
avail. How can I tweak the second command to get it working?