From 26b241c0791bfeb9df7b873da4dc74cce0c06be3 Mon Sep 17 00:00:00 2001 From: John Stebbins Date: Tue, 3 Sep 2013 10:53:34 -0700 Subject: [PATCH] matroskaenc: Allow chapters to be written in trailer This allows creation of frame accurate chapter marks from sources like DVD and BD where the precise chapter location is not known until the chapter mark has been reached during reading. Signed-off-by: Anton Khirnov --- libavformat/avformat.h | 11 +++++++++++ libavformat/matroskaenc.c | 10 +++++++++- 2 files changed, 20 insertions(+), 1 deletion(-) diff --git a/libavformat/avformat.h b/libavformat/avformat.h index 1399de052b..12462c8291 100644 --- a/libavformat/avformat.h +++ b/libavformat/avformat.h @@ -948,6 +948,17 @@ typedef struct AVFormatContext { */ unsigned int max_picture_buffer; + /** + * Number of chapters in AVChapter array. + * When muxing, chapters are normally written in the file header, + * so nb_chapters should normally be initialized before write_header + * is called. Some muxers (e.g. mov and mkv) can also write chapters + * in the trailer. To write chapters in the trailer, nb_chapters + * must be zero when write_header is called and non-zero when + * write_trailer is called. + * muxing : set by user + * demuxing: set by libavformat + */ unsigned int nb_chapters; AVChapter **chapters; diff --git a/libavformat/matroskaenc.c b/libavformat/matroskaenc.c index 825e92c82d..5edaa36c66 100644 --- a/libavformat/matroskaenc.c +++ b/libavformat/matroskaenc.c @@ -103,6 +103,7 @@ typedef struct MatroskaMuxContext { int cluster_size_limit; int64_t cues_pos; int64_t cluster_time_limit; + int wrote_chapters; } MatroskaMuxContext; @@ -710,7 +711,7 @@ static int mkv_write_chapters(AVFormatContext *s) AVRational scale = {1, 1E9}; int i, ret; - if (!s->nb_chapters) + if (!s->nb_chapters || mkv->wrote_chapters) return 0; ret = mkv_add_seekhead_entry(mkv->main_seekhead, MATROSKA_ID_CHAPTERS, avio_tell(pb)); @@ -743,6 +744,8 @@ static int mkv_write_chapters(AVFormatContext *s) } end_ebml_master(pb, editionentry); end_ebml_master(pb, chapters); + + mkv->wrote_chapters = 1; return 0; } @@ -1391,6 +1394,11 @@ static int mkv_write_trailer(AVFormatContext *s) end_ebml_master(pb, mkv->cluster); } + if (mkv->mode != MODE_WEBM) { + ret = mkv_write_chapters(s); + if (ret < 0) return ret; + } + if (pb->seekable) { if (mkv->cues->num_entries) { if (mkv->reserve_cues_space) {