[FFmpeg-devel] [PATCH] avformat/id3v2: Add Grouping frame to id3v2.4 metadata table

[Wolfgang Müller]

The ID3v2.4.0 standard defines TIT1 as the "Content group description"
tag [1]. This frame is usually referred to as the "Grouping" tag and in
de-facto use under that name by Vorbis and APEv2 [2].

This commit introduces a mapping from "TIT1" to "grouping" in the
id3v2.4 metadata conversion table. This will enable software to access
it using that name. In particular, MPD will now read this tag correctly
when using the ffmpeg decoder plugin.

[1] https://id3.org/id3v2.4.0-frames (4.2.1)
[2] https://picard-docs.musicbrainz.org/en/appendices/tag_mapping.html#grouping-3

Signed-off-by: Wolfgang Müller <wolf at oriole.systems>
---

As evident from the commit message, I ran into this using MPD with the
ffmpeg decoder plugin. MPD relies on these mappings heavily, and I found
it the easiest place to fix this particular issue, especially if other
pieces of software can also gain from this.

 libavformat/id3v2.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/libavformat/id3v2.c b/libavformat/id3v2.c
index ff27c062e5..0f9bedea02 100644
--- a/libavformat/id3v2.c
+++ b/libavformat/id3v2.c
@@ -69,6 +69,7 @@ const AVMetadataConv ff_id3v2_4_metadata_conv[] = {
     { "TSOA", "album-sort"    },
     { "TSOP", "artist-sort"   },
     { "TSOT", "title-sort"    },
+    { "TIT1", "grouping"      },
     { 0 }
 };
 
-- 
2.35.1