On Thu, 1 Feb 2018 18:37:45 -0800 rshaf...@tunein.com wrote: > From: Richard Shaffer <rshaf...@tunein.com> > > While rare, ID3 tags may be inserted between ADTS frames. This change enables > parsing them and setting the appropriate metadata updated event flag. > --- > I have encountered a streaming provider that I must support which does this. > There are indications that it isn't totally off the wall, and that it does > happen in the wild: > * https://www.w3.org/TR/mse-byte-stream-format-mpeg-audio/ > (See specifically sections 3 and 4.) > * https://github.com/video-dev/hls.js/issues/508 > > That being said, the providers that do this are in the minority. It seems most > streaming providers will do one of the following: > 1. If using .aac segments inside of HLS, use the #EXTINF for text metadata > and > use an ID3 tag at the head of the segment for things like timing metadata. > 2. If streaming raw AAC over HTTP, use Icy metadata. > > Aside from comments on the code, I'd be interested in any opinion about > whether > this is something that should or should not be supported in libavformat. > > Thanks, > > -Richard > > libavformat/aacdec.c | 45 +++++++++++++++++++++++++++++++++++++++++++-- > 1 file changed, 43 insertions(+), 2 deletions(-) > > diff --git a/libavformat/aacdec.c b/libavformat/aacdec.c > index 36d558ff54..5ec706bdc7 100644 > --- a/libavformat/aacdec.c > +++ b/libavformat/aacdec.c > @@ -22,8 +22,10 @@ > > #include "libavutil/intreadwrite.h" > #include "avformat.h" > +#include "avio_internal.h" > #include "internal.h" > #include "id3v1.h" > +#include "id3v2.h" > #include "apetag.h" > > #define ADTS_HEADER_SIZE 7 > @@ -116,13 +118,52 @@ static int adts_aac_read_header(AVFormatContext *s) > return 0; > } > > +static int handle_id3(AVFormatContext *s, AVPacket *pkt) > +{ > + AVDictionary *metadata = NULL; > + AVIOContext ioctx; > + ID3v2ExtraMeta *id3v2_extra_meta = NULL; > + int ret; > + > + ret = av_append_packet(s->pb, pkt, ff_id3v2_tag_len(pkt->data) - > pkt->size); > + if (ret < 0) { > + av_packet_unref(pkt); > + return ret; > + } > + > + ffio_init_context(&ioctx, pkt->data, pkt->size, 0, NULL, NULL, NULL, > NULL); > + ff_id3v2_read_dict(&ioctx, &metadata, ID3v2_DEFAULT_MAGIC, > &id3v2_extra_meta); > + if ((ret = ff_id3v2_parse_priv_dict(&metadata, &id3v2_extra_meta)) < 0) > + goto error; > + > + if (metadata) { > + if ((ret = av_dict_copy(&s->metadata, metadata, 0)) < 0) > + goto error; > + s->event_flags |= AVFMT_EVENT_FLAG_METADATA_UPDATED; > + } > + > +error: > + av_packet_unref(pkt); > + ff_id3v2_free_extra_meta(&id3v2_extra_meta); > + av_dict_free(&metadata); > + > + return ret; > +} > + > static int adts_aac_read_packet(AVFormatContext *s, AVPacket *pkt) > { > int ret, fsize; > > - ret = av_get_packet(s->pb, pkt, ADTS_HEADER_SIZE); > + ret = av_get_packet(s->pb, pkt, FFMAX(ID3v2_HEADER_SIZE, > ADTS_HEADER_SIZE)); > + > + if (ret >= ID3v2_HEADER_SIZE && ff_id3v2_match(pkt->data, > ID3v2_DEFAULT_MAGIC)) { > + if ((ret = handle_id3(s, pkt)) >= 0) > + ret = av_get_packet(s->pb, pkt, ADTS_HEADER_SIZE); > + } > + > if (ret < 0) > return ret; > + > if (ret < ADTS_HEADER_SIZE) { > av_packet_unref(pkt); > return AVERROR(EIO); > @@ -139,7 +180,7 @@ static int adts_aac_read_packet(AVFormatContext *s, > AVPacket *pkt) > return AVERROR_INVALIDDATA; > } > > - ret = av_append_packet(s->pb, pkt, fsize - ADTS_HEADER_SIZE); > + ret = av_append_packet(s->pb, pkt, fsize - pkt->size); > if (ret < 0) > av_packet_unref(pkt); >
Applied. (I hope this is the most recent version...) _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
