avformat/ivfenc: use the av1_metadata bsf to insert Temporal Delimiter OBUs if needed

Reviewed-by: Mark Thompson <sw@jkqxz.net>
Signed-off-by: James Almer <jamrial@gmail.com>

configure

@@ -3180,6 +3180,7 @@ image2_alias_pix_demuxer_select="image2_demuxer"
 image2_brender_pix_demuxer_select="image2_demuxer"
 ipod_muxer_select="mov_muxer"
 ismv_muxer_select="mov_muxer"
+ivf_muxer_select="av1_metadata"
 matroska_audio_muxer_select="matroska_muxer"
 matroska_demuxer_select="iso_media riffdec"
 matroska_demuxer_suggest="bzlib lzo zlib"

libavformat/ivfenc.c

@@ -97,6 +97,8 @@ static int ivf_check_bitstream(struct AVFormatContext *s, const AVPacket *pkt)
 
     if (st->codecpar->codec_id == AV_CODEC_ID_VP9)
         ret = ff_stream_add_bitstream_filter(st, "vp9_superframe", NULL);
+    else if (st->codecpar->codec_id == AV_CODEC_ID_AV1)
+        ret = ff_stream_add_bitstream_filter(st, "av1_metadata", "td=insert");
 
     return ret;
 }