[FFmpeg-devel] [PATCH] doc/bitstream_filters: document dump_extra

[Stefano Sabatini]

---
 doc/bitstream_filters.texi | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/doc/bitstream_filters.texi b/doc/bitstream_filters.texi
index fe3c910..d12aa0e 100644
--- a/doc/bitstream_filters.texi
+++ b/doc/bitstream_filters.texi
@@ -32,6 +32,36 @@ Remove zero padding at the end of a packet.
 
 @section dump_extra
 
+Add extradata to the beginning of the filtered packets.
+
+The additional arguments specifies which packets should be filtered.
+
+ at table @samp
+ at item a
+add extradata to all key packets, assuming that @var{local_header} is
+set in in the @option{flags2} codec context field
+
+ at item k
+add extradata to all key packets
+
+ at item e
+add extradata to all packets
+ at end table
+
+If not specified it is assumed @samp{k}.
+
+This filter is useful for example to manipulate bitstreams which
+specify a global header in extradata, but which was removed from the
+packet headers.
+
+For example the following @command{ffmpeg} command allows to force a
+global header (thus disabling individual packet headers) in the H.264
+packets generated by the @code{libx264}, but correct them by adding
+the header stored in the extradata to the key packets:
+ at example
+ffmpeg -i INPUT -map 0 -flags:v +global_header -c:v libx264 -bsf:v dump_extra -y out.ts
+ at end example
+
 @section h264_mp4toannexb
 
 Convert an H.264 bitstream from length prefixed mode to start code
-- 
1.8.1.2