On Wed, Jul 12, 2017 at 9:16 AM, Louis O'Bryan <lou...@google.com> wrote:
> On Wed, Jul 12, 2017 at 12:50 AM, wm4 <nfx...@googlemail.com> wrote: > >> On Tue, 11 Jul 2017 16:17:33 -0700 >> "Louis O'Bryan" <louiso-at-google....@ffmpeg.org> wrote: >> >> > If I need to write a new atom under stsd for my stream in the mov muxer >> > <https://github.com/FFmpeg/FFmpeg/blob/master/libavformat/movenc.c> >> > (mov_write_stsd_tag), >> > is it appropriate to indicate that through the AVStream metadata rather >> > than the codec_tag? >> >> It seemed to have lots of unrelated changes, but maybe I'm missing >> something. If those codec tag refactors are needed, they should >> probably be split into a separate patch. >> >> But it looks like most of those changes were unintended (Moritz >> suspected that too). The tag addition itself is probably fine. >> >> Also, please don't top post on mailing lists. >> _______________________________________________ >> ffmpeg-devel mailing list >> ffmpeg-devel@ffmpeg.org >> http://ffmpeg.org/mailman/listinfo/ffmpeg-devel >> > > That file had unrelated changes that shouldn't have been there, please > ignore them. > Now that there is no codec associated with the stream, there shouldn't be > a codec tag at all, I would assume. (Another issue I need to deal with is > that the MOV muxer also doesn't support streams without a codec, but that > is separate.) > My goal is to modify the MOV/MP4 muxer so that I can mux the new stream with video and audio streams. Part of that is writing a new sample entry box under the stsd box. Since I no longer plan to use an encoder for the stream, I was wondering if the AVStream::metadata <https://www.ffmpeg.org/doxygen/3.2/structAVStream.html#a50d250a128a3da9ce3d135e84213fb82> would be an appropriate way to recognize that stream. Other cases in the mov_write_stsd_tag function use the codec tag. I have the following sample of that idea here, which allows me to use the new stream and write the sample entry box: --- libavformat/movenc.c | 24 +++++++++++++++++++++++- 1 file changed, 23 insertions(+), 1 deletion(-) diff --git a/libavformat/movenc.c b/libavformat/movenc.c index 88f2f2c819..8d57a18864 100644 --- a/libavformat/movenc.c +++ b/libavformat/movenc.c @@ -109,6 +109,13 @@ static const AVClass flavor ## _muxer_class = {\ static int get_moov_size(AVFormatContext *s); +static int stream_has_metadata(AVStream *st, const char *metadata_key) { + if (!st->metadata) { + return 0; + } + return av_dict_get(st->metadata, metadata_key, NULL, 0) != NULL; +} + static int utf8len(const uint8_t *b) { int len = 0; @@ -2060,6 +2067,16 @@ static int mov_write_tmcd_tag(AVIOContext *pb, MOVTrack *track) return update_size(pb, pos); } +static int mov_write_camm_tag(AVIOContext *pb) { + int64_t pos = avio_tell(pb); + avio_wb32(pb, 0); /* size */ + ffio_wfourcc(pb, "camm"); + avio_wb32(pb, 0); /* Reserved */ + avio_wb16(pb, 0); /* Reserved */ + avio_wb16(pb, 1); /* Data-reference index */ + return update_size(pb, pos); +} + static int mov_write_stsd_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContext *mov, MOVTrack *track) { int64_t pos = avio_tell(pb); @@ -2077,6 +2094,8 @@ static int mov_write_stsd_tag(AVFormatContext *s, AVIOContext *pb, MOVMuxContext mov_write_rtp_tag(pb, track); else if (track->par->codec_tag == MKTAG('t','m','c','d')) mov_write_tmcd_tag(pb, track); + else if (stream_has_metadata(track->st, "camm")) + mov_write_camm_tag(pb); return update_size(pb, pos); } @@ -2443,6 +2462,9 @@ static int mov_write_hdlr_tag(AVFormatContext *s, AVIOContext *pb, MOVTrack *tra } else if (track->par->codec_tag == MKTAG('t','m','c','d')) { hdlr_type = "tmcd"; descr = "TimeCodeHandler"; + } else if (stream_has_metadata(track->st, "camm")) { + hdlr_type = "camm"; + descr = "CameraMetadataMotionHandler"; } else { av_log(s, AV_LOG_WARNING, "Unknown hldr_type for %s, writing dummy values\n", @@ -5875,7 +5897,7 @@ static int mov_init(AVFormatContext *s) track->language = 0; track->mode = mov->mode; track->tag = mov_find_codec_tag(s, track); - if (!track->tag) { + if (!track->tag && !stream_has_metadata(st, "camm")) { av_log(s, AV_LOG_ERROR, "Could not find tag for codec %s in stream #%d, " "codec not currently supported in container\n", avcodec_get_name(st->codecpar->codec_id), i); -- 2.13.2.932.g7449e964c-goog _______________________________________________ ffmpeg-devel mailing list ffmpeg-devel@ffmpeg.org http://ffmpeg.org/mailman/listinfo/ffmpeg-devel
