Merge remote-tracking branch 'qatar/master'

* qatar/master:
  matroskaenc: Allow chapters to be written in trailer

Conflicts:
	libavformat/matroskaenc.c

Merged-by: Michael Niedermayer <michaelni@gmx.at>

1 files changed, 11 insertions, 0 deletions

diff --git a/libavformat/avformat.h b/libavformat/avformat.h
index 5c07887e9b..9dea62eb5f 100644
--- a/libavformat/avformat.h
+++ b/libavformat/avformat.h
@@ -1101,6 +1101,17 @@ 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;