[FFmpeg-devel] [PATCH] mp3 muxer: write all metadata

[Justin Ruggles]

Anton Khirnov wrote:

> Hi,
> with attached patch the mp3 muxer will write all available metadata, not
> just a few selected as it does now.
> 
> btw shouldn't there be a list of standard ffmpeg tag names somewhere?


I agree that we should have a list of generic tag names (and their
formats if applicable).

> From ced4fae2478201b70b417f8a10c6be5d6d4404b6 Mon Sep 17 00:00:00 2001

> From: Anton Khirnov <wyskas at gmail.com>
> Date: Fri, 25 Sep 2009 09:04:42 +0200
> Subject: [PATCH] mp3 muxer: write all metadata
> 
> ---
>  libavformat/mp3.c |   86 ++++++++++++++++++++++++++++++++---------------------
>  1 files changed, 52 insertions(+), 34 deletions(-)
> 
> [...]
> +        if      (!strcmp(t->key, "album"))    tag = MKBETAG('T', 'A', 'L', 'B');
> +        else if (!strcmp(t->key, "composer")) tag = MKBETAG('T', 'C', 'O', 'M');
> +        else if (!strcmp(t->key, "genre"))    tag = MKBETAG('T', 'C', 'O', 'N');
> +        else if (!strcmp(t->key, "copyright"))tag = MKBETAG('T', 'C', 'O', 'P');
> +        else if (!strcmp(t->key, "date"))     tag = MKBETAG('T', 'D', 'R', 'L');


Using "date" is not compatible with other metadata readers/writers,
which all use "year".  Personally I think that all the readers/writers
should be changed to use "date" instead, in ISO format so that the year
would be the first 4 chars.  That way it would be usable for those
formats that only support the year.  An alternative would be to have a
fallback to use "year" for TDRL if "date" does not exist.

-Justin