[FFmpeg-devel] [PATCH] matroskaenc: write tags.

[David Conrad]

On Mar 20, 2010, at 4:51 AM, Anton Khirnov wrote:

> added a metadata conv table to the muxer + it now adds per-track/chapter
> tags to the cluster seekhead, not main.
> 
> Anton Khirnov

Why can't all tags be stored in one level-one element? At least, I don't see from the spec why this wouldn't work.

> +    simpletag = start_ebml_master(s->pb, MATROSKA_ID_SIMPLETAG, 0);
> +    put_ebml_string(s->pb, MATROSKA_ID_TAGNAME, t->key);
> +    put_ebml_string(s->pb, MATROSKA_ID_TAGLANG, "und");
> +    put_ebml_uint(  s->pb, MATROSKA_ID_TAGDEFAULT, 1);

No need to write mandatory elements if we never use anything but the default value.

> +    if (av_metadata_get(s->metadata, "", NULL, AV_METADATA_IGNORE_SUFFIX)) {
> +        ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_TAGS, url_ftell(s->pb));
> +        if (ret < 0) return ret;
> +
> +        tags = start_ebml_master(s->pb, MATROSKA_ID_TAGS, 0);
> +
> +        while ((t = av_metadata_get(s->metadata, "", t, AV_METADATA_IGNORE_SUFFIX)))

Don't need the extra () here or down further.