I am writing the aiff metadata with this line:
ffmpeg -i uno.aiff -metadata title=Track -metadata artist=Band -f aiff dos.aiff
but iTunes done recognize the metadata. What I am doing wrong?
Use -write_id3v2 1 as an output option:
ffmpeg -i in.aiff -c copy -write_id3v2 1 -metadata title="Title" \
-metadata artist="Artist" out.aiff
You can add -c copy to stream copy instead of re-encoding if you just want to add metadata.
-f aiff is superfluous in your example since ffmpeg can guess the correct muxer via the output file name.