Add adaptive streaming support (#972)

"Adaptive streaming" allows changing video parameters mid-stream at IDR
boundaries.  Such changes require new SPS and PPS NALs at the IDR.  MP4
supports this with 'avc3' and 'hev1' sample entry types.

2 files changed, 49 insertions, 48 deletions

diff --git a/contrib/ffmpeg/A20-avc3-hvc1-override.patch b/contrib/ffmpeg/A20-avc3-hvc1-override.patch
new file mode 100644
index 000000000..70d67b4a3
--- /dev/null
+++ b/contrib/ffmpeg/A20-avc3-hvc1-override.patch
@@ -0,0 +1,49 @@
+diff -ur libav-12.2.orig/libavformat/isom.c libav-12.2/libavformat/isom.c
+--- libav-12.2.orig/libavformat/isom.c	2017-09-30 11:13:39.000000000 -0700
++++ libav-12.2/libavformat/isom.c	2017-11-01 14:17:30.762856002 -0700
+@@ -152,6 +152,7 @@
+     { AV_CODEC_ID_HEVC, MKTAG('h', 'v', 'c', '1') }, /* HEVC/H.265 which indicates parameter sets shall not be in ES */
+ 
+     { AV_CODEC_ID_H264, MKTAG('a', 'v', 'c', '1') }, /* AVC-1/H.264 */
++    { AV_CODEC_ID_H264, MKTAG('a', 'v', 'c', '3') }, /* AVC-1/H.264 */
+     { AV_CODEC_ID_H264, MKTAG('a', 'i', '5', 'p') }, /* AVC-Intra  50M 720p24/30/60 */
+     { AV_CODEC_ID_H264, MKTAG('a', 'i', '5', 'q') }, /* AVC-Intra  50M 720p25/50 */
+     { AV_CODEC_ID_H264, MKTAG('a', 'i', '5', '2') }, /* AVC-Intra  50M 1080p25/50 */
+diff -ur libav-12.2.orig/libavformat/movenc.c libav-12.2/libavformat/movenc.c
+--- libav-12.2.orig/libavformat/movenc.c	2017-09-30 11:13:39.000000000 -0700
++++ libav-12.2/libavformat/movenc.c	2017-11-01 14:20:52.783487291 -0700
+@@ -724,7 +724,10 @@
+ 
+     avio_wb32(pb, 0);
+     ffio_wfourcc(pb, "hvcC");
+-    ff_isom_write_hvcc(pb, track->vos_data, track->vos_len, 0);
++    if (track->tag == MKTAG('h','v','c','1'))
++        ff_isom_write_hvcc(pb, track->vos_data, track->vos_len, 1);
++    else
++        ff_isom_write_hvcc(pb, track->vos_data, track->vos_len, 0);
+     return update_size(pb, pos);
+ }
+ 
+@@ -783,7 +786,11 @@
+     if (!ff_codec_get_tag(ff_mp4_obj_type, track->par->codec_id))
+         return 0;
+ 
+-    if      (track->par->codec_id == AV_CODEC_ID_H264)      tag = MKTAG('a','v','c','1');
++    if      (track->par->codec_id == AV_CODEC_ID_H264 &&
++             tag == MKTAG('a','v','c','3'))                 ;
++    else if (track->par->codec_id == AV_CODEC_ID_H264)      tag = MKTAG('a','v','c','1');
++    else if (track->par->codec_id == AV_CODEC_ID_HEVC &&
++             tag == MKTAG('h','v','c','1'))                 ;
+     else if (track->par->codec_id == AV_CODEC_ID_HEVC)      tag = MKTAG('h','e','v','1');
+     else if (track->par->codec_id == AV_CODEC_ID_AC3)       tag = MKTAG('a','c','-','3');
+     else if (track->par->codec_id == AV_CODEC_ID_DIRAC)     tag = MKTAG('d','r','a','c');
+@@ -4476,7 +4483,7 @@
+     .write_packet      = mov_write_packet,
+     .write_trailer     = mov_write_trailer,
+     .flags             = AVFMT_GLOBALHEADER | AVFMT_ALLOW_FLUSH | AVFMT_TS_NEGATIVE,
+-    .codec_tag         = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 },
++    .codec_tag         = (const AVCodecTag* const []){ ff_codec_movvideo_tags, ff_codec_movaudio_tags, ff_codec_movsubtitle_tags, 0 },
+     .priv_class        = &mp4_muxer_class,
+ };
+ #endif
+Only in libav-12.2/libavformat: movenc.c.orig
diff --git a/contrib/ffmpeg/A20-hvc1-override.patch b/contrib/ffmpeg/A20-hvc1-override.patch
deleted file mode 100644
index 639885ebb..000000000
--- a/contrib/ffmpeg/A20-hvc1-override.patch
+++ /dev/null
@@ -1,48 +0,0 @@
-From cc6cb8d44b50082ae3edfed39f484213590c8777 Mon Sep 17 00:00:00 2001
-From: John Stebbins <[email protected]>
-Date: Sun, 11 Jun 2017 10:19:14 -0700
-Subject: [PATCH] movenc: Allow use of hvc1 tag for h.265
-
-If AVCodecParameters.codec_tag is 'hvc1' use it instead of 'hev1' for
-h.265 streams.
----
- libavformat/movenc.c | 9 +++++++--
- 1 file changed, 7 insertions(+), 2 deletions(-)
-
-diff --git a/libavformat/movenc.c b/libavformat/movenc.c
-index e389029..835f588 100644
---- a/libavformat/movenc.c
-+++ b/libavformat/movenc.c
-@@ -726,7 +726,10 @@ static int mov_write_hvcc_tag(AVIOContext *pb, MOVTrack *track)
- 
-     avio_wb32(pb, 0);
-     ffio_wfourcc(pb, "hvcC");
--    ff_isom_write_hvcc(pb, track->vos_data, track->vos_len, 0);
-+    if (track->tag == MKTAG('h','v','c','1'))
-+        ff_isom_write_hvcc(pb, track->vos_data, track->vos_len, 1);
-+    else
-+        ff_isom_write_hvcc(pb, track->vos_data, track->vos_len, 0);
-     return update_size(pb, pos);
- }
- 
-@@ -786,6 +789,8 @@ static int mp4_get_codec_tag(AVFormatContext *s, MOVTrack *track)
-         return 0;
- 
-     if      (track->par->codec_id == AV_CODEC_ID_H264)      tag = MKTAG('a','v','c','1');
-+    else if (track->par->codec_id == AV_CODEC_ID_HEVC &&
-+             tag == MKTAG('h','v','c','1'))                 ;
-     else if (track->par->codec_id == AV_CODEC_ID_HEVC)      tag = MKTAG('h','e','v','1');
-     else if (track->par->codec_id == AV_CODEC_ID_AC3)       tag = MKTAG('a','c','-','3');
-     else if (track->par->codec_id == AV_CODEC_ID_DIRAC)     tag = MKTAG('d','r','a','c');
-@@ -4496,7 +4501,7 @@ AVOutputFormat ff_mp4_muxer = {
-     .write_packet      = mov_write_packet,
-     .write_trailer     = mov_write_trailer,
-     .flags             = AVFMT_GLOBALHEADER | AVFMT_ALLOW_FLUSH | AVFMT_TS_NEGATIVE,
--    .codec_tag         = (const AVCodecTag* const []){ ff_mp4_obj_type, 0 },
-+    .codec_tag         = (const AVCodecTag* const []){ ff_codec_movvideo_tags, ff_codec_movaudio_tags, ff_codec_movsubtitle_tags, 0 },
-     .priv_class        = &mp4_muxer_class,
- };
- #endif
--- 
-2.9.3
-