Rodolfo Medina <[email protected]> writes: > Moritz Barsnick <[email protected]> writes: > >> On Mon, May 29, 2017 at 18:37:31 -0400, Ron Sparks wrote: >>> > ... I also tried to remove all the tags with: >>> > $ ffmpeg -i input.mp3 -map 0:a -map_metadata -1 -c copy out.mp3 >>> > and then put them again, but the problem remains... >>> >>> I suspect the problem might be that ffmpeg works with the id3v2 tags, >>> while your mp3 reader works with the id3v1 tags. >> >> I had the same thought, but why would ffmpeg, when remuxing, re-insert >> the original id3v1 tags? Perhaps they're considered part of the stream, >> *then* they would survive "-c:a copy". >> >> You may want to try adding "-write_id3v1 1", as hinted in the docs: >> https://www.ffmpeg.org/ffmpeg-formats.html#mp3 >> >> In both cases, that should either drop the metadata or insert both >> versions. (I didn't manage to test, because I don't have any tools at >> hand which expose both/all types of tags in MP3 files. exiftool should >> manage.) >> >> Other suggestion (never confirmed): >> https://lists.ffmpeg.org/pipermail/ffmpeg-user/2011-June/001365.html >> >> Actually, there are so many forms of tags (incl. EXIF), metadata, and >> so on, that other tools may be much more suitable for such operations. >> >> Cheers, >> Moritz >> >> P.S.: I found "-map_metadata -1" on lists and superuser.com, but >> neither in the docs nor the wiki. Hmmm. > > > Unfortunately "-write_id3v1 1" seems to have no effect. I wish I could > understand what the problem is. Let input.mp3 be our file. I do: > > $ ffmpeg -i input.mp3 - c copy -metadata composer="Bach" output.mp3 > $ mv -vi output.mp3 input.mp3 > > , then get on my car and the reader reads fine the `composer' tag as `Bach'. > Then I remember that J. S. Bach had children who were composers as well, get > off the car, go to the PC and do: > > $ ffmpeg -i input.mp3 - c copy -metadata composer="Bach J. S." output.mp3 > $ mv -vi output.mp3 input.mp3 > > . Then I get back to the car and the reader keeps on reading simply `Bach' > instead of `Bach J. S.' I.e., it does not see the change occurred. Now, you > listers say that the problem is in that ffmpeg works with id3v2 tags whereas > my car's mp3 reader does it with id3v1. But, if so, why does it read them > correctly the first time they are created and not the second time, when they > have been changed? Besides, it seems that sometimes, when the above ffmpeg > command is repeated many times, at least the change is somewhat by my reader > finally seen: but only after repeating it at least twice.
Further tests show that changes in tags are actually detected by the reader but with a delay: in a first moment they are not, then I `play' again with tags using ffmpeg and then the reader finally reads them... Rodolfo _______________________________________________ ffmpeg-user mailing list [email protected] http://ffmpeg.org/mailman/listinfo/ffmpeg-user To unsubscribe, visit link above, or email [email protected] with subject "unsubscribe".
