lavf: add a flag to enable/disable automatic bitstream filtering

This is mostly useful for muxers that wrap other muxers, such as dashenc
and segment. The actual duplicated bitstream filtering is largely harmless,
but delaying the header can cause problems when the muxer intended the header
to be written to a separate file.

1 files changed, 4 insertions, 1 deletions

diff --git a/libavformat/mux.c b/libavformat/mux.c
index 176af59f13..bbfc0fccb8 100644
--- a/libavformat/mux.c
+++ b/libavformat/mux.c
@@ -500,7 +500,7 @@ int avformat_write_header(AVFormatContext *s, AVDictionary **options)
     if ((ret = init_muxer(s, options)) < 0)
         return ret;
 
-    if (!s->oformat->check_bitstream) {
+    if (!(s->oformat->check_bitstream && s->flags & AVFMT_FLAG_AUTO_BSF)) {
         ret = write_header_internal(s);
         if (ret < 0)
             goto fail;
@@ -830,6 +830,9 @@ static int do_packet_auto_bsf(AVFormatContext *s, AVPacket *pkt) {
     AVStream *st = s->streams[pkt->stream_index];
     int i, ret;
 
+    if (!(s->flags & AVFMT_FLAG_AUTO_BSF))
+        return 1;
+
     if (s->oformat->check_bitstream) {
         if (!st->internal->bitstream_checked) {
             if ((ret = s->oformat->check_bitstream(s, pkt)) < 0)