avformat/mux: Store pointer to interleavement func in FFFormatContext

It avoids branches lateron and will allow to easily avoid the overhead
of the linked list currently in use in case there is only one stream.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

2 files changed, 11 insertions, 14 deletions

diff --git a/libavformat/internal.h b/libavformat/internal.h
index 1f301dd17a..290e114506 100644
--- a/libavformat/internal.h
+++ b/libavformat/internal.h
@@ -82,6 +82,12 @@ typedef struct FFFormatContext {
     int nb_interleaved_streams;
 
     /**
+     * The interleavement function in use. Always set for muxers.
+     */
+    int (*interleave_packet)(struct AVFormatContext *s, AVPacket *pkt,
+                             int flush, int has_packet);
+
+    /**
      * This buffer is only needed when packets were already buffered but
      * not decoded, for example to get the codec parameters in MPEG
      * streams.
diff --git a/libavformat/mux.c b/libavformat/mux.c
index a6e1a08be0..884640611a 100644
--- a/libavformat/mux.c
+++ b/libavformat/mux.c
@@ -334,6 +334,9 @@ static int init_muxer(AVFormatContext *s, AVDictionary **options)
         if (par->codec_type != AVMEDIA_TYPE_ATTACHMENT)
             si->nb_interleaved_streams++;
     }
+    si->interleave_packet = of->interleave_packet;
+    if (!si->interleave_packet)
+        si->interleave_packet = ff_interleave_packet_per_dts;
 
     if (!s->priv_data && of->priv_data_size > 0) {
         s->priv_data = av_mallocz(of->priv_data_size);
@@ -1054,19 +1057,6 @@ const AVPacket *ff_interleaved_peek(AVFormatContext *s, int stream)
     return NULL;
 }
 
-/**
- * A wrapper around AVOutputFormat.interleave_packet.
- * See its documentation for details.
- */
-static int interleave_packet(AVFormatContext *s, AVPacket *pkt,
-                             int flush, int has_packet)
-{
-    if (s->oformat->interleave_packet) {
-        return s->oformat->interleave_packet(s, pkt, flush, has_packet);
-    } else
-        return ff_interleave_packet_per_dts(s, pkt, flush, has_packet);
-}
-
 static int check_bitstream(AVFormatContext *s, FFStream *sti, AVPacket *pkt)
 {
     int ret;
@@ -1089,8 +1079,9 @@ static int check_bitstream(AVFormatContext *s, FFStream *sti, AVPacket *pkt)
 static int interleaved_write_packet(AVFormatContext *s, AVPacket *pkt,
                                     int flush, int has_packet)
 {
+    FFFormatContext *const si = ffformatcontext(s);
     for (;; ) {
-        int ret = interleave_packet(s, pkt, flush, has_packet);
+        int ret = si->interleave_packet(s, pkt, flush, has_packet);
         if (ret <= 0)
             return ret;