[FFmpeg-devel] [PATCH v3 5/5] avformat/{isom, movenc}: add kind box compatibility mode for Unified Origin

Jan Ekström jeebjp at gmail.com
Mon Sep 20 18:00:48 EEST 2021


From: Jan Ekström <jan.ekstrom at 24i.com>

Unfortunately the current production versions of this software
do not 100% adhere to the CMAF specification, and have decided
to utilize the HTML5 media track identifier for audio descriptions.

This way the default mode of operation is according to the CMAF
specification, but it is also possible to output streams with which
this piece of software is capable of interoperating with.

Signed-off-by: Jan Ekström <jan.ekstrom at 24i.com>
---
 libavformat/isom.c                            | 23 ++++--
 libavformat/isom.h                            |  7 ++
 libavformat/movenc.c                          | 12 ++-
 libavformat/movenc.h                          |  2 +
 tests/fate/mov.mak                            |  8 ++
 ...p4-disposition-unified-origin-mpegts-remux | 81 +++++++++++++++++++
 6 files changed, 125 insertions(+), 8 deletions(-)
 create mode 100644 tests/ref/fate/mov-mp4-disposition-unified-origin-mpegts-remux

diff --git a/libavformat/isom.c b/libavformat/isom.c
index 300ba927c2..512ffba651 100644
--- a/libavformat/isom.c
+++ b/libavformat/isom.c
@@ -433,19 +433,32 @@ void ff_mov_write_chan(AVIOContext *pb, int64_t channel_layout)
 
 static const struct MP4TrackKindValueMapping dash_role_map[] = {
     { AV_DISPOSITION_HEARING_IMPAIRED|AV_DISPOSITION_CAPTIONS,
-        "caption" },
+        "caption",
+        KindWritingModeCMAF | KindWritingModeUnifiedOrigin },
     { AV_DISPOSITION_COMMENT,
-        "commentary" },
+        "commentary",
+        KindWritingModeCMAF | KindWritingModeUnifiedOrigin },
     { AV_DISPOSITION_VISUAL_IMPAIRED|AV_DISPOSITION_DESCRIPTIONS,
-        "description" },
+        "description",
+        KindWritingModeCMAF },
     { AV_DISPOSITION_DUB,
-        "dub" },
+        "dub",
+        KindWritingModeCMAF | KindWritingModeUnifiedOrigin },
     { AV_DISPOSITION_FORCED,
-        "forced-subtitle" },
+        "forced-subtitle",
+        KindWritingModeCMAF | KindWritingModeUnifiedOrigin },
+    { 0, NULL }
+};
+
+static const struct MP4TrackKindValueMapping html_kind_map[] = {
+    { AV_DISPOSITION_VISUAL_IMPAIRED|AV_DISPOSITION_DESCRIPTIONS,
+        "main-desc",
+         KindWritingModeUnifiedOrigin },
     { 0, NULL }
 };
 
 const struct MP4TrackKindMapping ff_mov_track_kind_table[] = {
     { "urn:mpeg:dash:role:2011", dash_role_map },
+    { "about:html-kind",         html_kind_map },
     { 0, NULL }
 };
diff --git a/libavformat/isom.h b/libavformat/isom.h
index c62fcf2bfe..f0381e9a8e 100644
--- a/libavformat/isom.h
+++ b/libavformat/isom.h
@@ -390,9 +390,16 @@ static inline enum AVCodecID ff_mov_get_lpcm_codec_id(int bps, int flags)
 #define MOV_ISMV_TTML_TAG MKTAG('d', 'f', 'x', 'p')
 #define MOV_MP4_TTML_TAG  MKTAG('s', 't', 'p', 'p')
 
+enum MP4TrackKindWritingMode {
+    KindWritingModeCMAF          = (1 << 0),
+    KindWritingModeUnifiedOrigin = (1 << 1),
+    KindWritingModeNB,
+};
+
 struct MP4TrackKindValueMapping {
     int         disposition;
     const char *value;
+    uint32_t    writing_modes;
 };
 
 struct MP4TrackKindMapping {
diff --git a/libavformat/movenc.c b/libavformat/movenc.c
index 0c4a24c313..1550bdd16f 100644
--- a/libavformat/movenc.c
+++ b/libavformat/movenc.c
@@ -111,6 +111,9 @@ static const AVOption options[] = {
     { "pts", NULL, 0, AV_OPT_TYPE_CONST, {.i64 = MOV_PRFT_SRC_PTS}, 0, 0, AV_OPT_FLAG_ENCODING_PARAM, "prft"},
     { "empty_hdlr_name", "write zero-length name string in hdlr atoms within mdia and minf atoms", offsetof(MOVMuxContext, empty_hdlr_name), AV_OPT_TYPE_BOOL, {.i64 = 0}, 0, 1, AV_OPT_FLAG_ENCODING_PARAM},
     { "movie_timescale", "set movie timescale", offsetof(MOVMuxContext, movie_timescale), AV_OPT_TYPE_INT, {.i64 = MOV_TIMESCALE}, 1, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM},
+    { "kind_writing_mode", "set kind box writing mode", offsetof(MOVMuxContext, kind_writing_mode), AV_OPT_TYPE_INT, {.i64 = KindWritingModeCMAF}, KindWritingModeCMAF, KindWritingModeNB - 1, AV_OPT_FLAG_ENCODING_PARAM, "kind_writing_mode"},
+        { "cmaf", "CMAF writing mode", 0, AV_OPT_TYPE_CONST, {.i64 = KindWritingModeCMAF}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "kind_writing_mode"},
+        { "unified_origin", "Compatibility mode for Unified Origin (all DASH except for audio description)", 0, AV_OPT_TYPE_CONST, {.i64 = KindWritingModeUnifiedOrigin}, INT_MIN, INT_MAX, AV_OPT_FLAG_ENCODING_PARAM, "kind_writing_mode"},
     { NULL },
 };
 
@@ -3355,7 +3358,8 @@ static int mov_write_track_kind(AVIOContext *pb, const char *scheme_uri,
     return update_size(pb, pos);
 }
 
-static int mov_write_track_kinds(AVIOContext *pb, AVStream *st)
+static int mov_write_track_kinds(AVIOContext *pb, AVStream *st,
+                                 enum MP4TrackKindWritingMode mode)
 {
     int ret = AVERROR_BUG;
 
@@ -3364,7 +3368,8 @@ static int mov_write_track_kinds(AVIOContext *pb, AVStream *st)
 
         for (int j = 0; map.value_maps[j].disposition; j++) {
             const struct MP4TrackKindValueMapping value_map = map.value_maps[j];
-            if (!(st->disposition & value_map.disposition))
+            if (!(st->disposition & value_map.disposition) ||
+                !(value_map.writing_modes & mode))
                 continue;
 
             if ((ret = mov_write_track_kind(pb, map.scheme_uri, value_map.value)) < 0)
@@ -3393,7 +3398,8 @@ static int mov_write_track_udta_tag(AVIOContext *pb, MOVMuxContext *mov,
         mov_write_track_metadata(pb_buf, st, "name", "title");
 
     if (mov->mode & MODE_MP4) {
-        if ((ret = mov_write_track_kinds(pb_buf, st)) < 0)
+        if ((ret = mov_write_track_kinds(pb_buf, st,
+                                         mov->kind_writing_mode)) < 0)
             return ret;
     }
 
diff --git a/libavformat/movenc.h b/libavformat/movenc.h
index 40077b1afe..e02a086b1f 100644
--- a/libavformat/movenc.h
+++ b/libavformat/movenc.h
@@ -25,6 +25,7 @@
 #define AVFORMAT_MOVENC_H
 
 #include "avformat.h"
+#include "isom.h"
 #include "movenccenc.h"
 #include "libavcodec/packet_internal.h"
 
@@ -242,6 +243,7 @@ typedef struct MOVMuxContext {
     MOVPrftBox write_prft;
     int empty_hdlr_name;
     int movie_timescale;
+    enum MP4TrackKindWritingMode kind_writing_mode;
 } MOVMuxContext;
 
 #define FF_MOV_FLAG_RTP_HINT              (1 <<  0)
diff --git a/tests/fate/mov.mak b/tests/fate/mov.mak
index 5ca992e181..20f085803b 100644
--- a/tests/fate/mov.mak
+++ b/tests/fate/mov.mak
@@ -145,6 +145,14 @@ FATE_MOV_FFMPEG_FFPROBE-$(call ALLYES, FILE_PROTOCOL PIPE_PROTOCOL \
                           += fate-mov-mp4-disposition-mpegts-remux
 fate-mov-mp4-disposition-mpegts-remux: CMD = transcode mpegts $(TARGET_SAMPLES)/mpegts/pmtchange.ts mp4 "-map 0:1 -map 0:2 -c copy -disposition:a:0 +hearing_impaired" "-map 0 -c copy" "" "-of json -show_entries stream_disposition:stream=index"
 
+# Same as the previous test, but the audio disposition should now be tagged
+# with the HTML5 media track identifier as opposed to the DASH identifier.
+FATE_MOV_FFMPEG_FFPROBE-$(call ALLYES, FILE_PROTOCOL PIPE_PROTOCOL \
+                                       MPEGTS_DEMUXER MOV_DEMUXER AC3_DECODER \
+                                       MP4_MUXER FRAMECRC_MUXER ) \
+                          += fate-mov-mp4-disposition-unified-origin-mpegts-remux
+fate-mov-mp4-disposition-unified-origin-mpegts-remux: CMD = transcode mpegts $(TARGET_SAMPLES)/mpegts/pmtchange.ts mp4 "-map 0:1 -map 0:2 -c copy -disposition:a:0 +hearing_impaired -kind_writing_mode unified_origin" "-map 0 -c copy" "" "-of json -show_entries stream_disposition:stream=index"
+
 FATE_SAMPLES_FFMPEG_FFPROBE += $(FATE_MOV_FFMPEG_FFPROBE-yes)
 
 fate-mov: $(FATE_MOV) $(FATE_MOV_FFPROBE) $(FATE_MOV_FASTSTART) $(FATE_MOV_FFMPEG_FFPROBE-yes)
diff --git a/tests/ref/fate/mov-mp4-disposition-unified-origin-mpegts-remux b/tests/ref/fate/mov-mp4-disposition-unified-origin-mpegts-remux
new file mode 100644
index 0000000000..0242cffb9b
--- /dev/null
+++ b/tests/ref/fate/mov-mp4-disposition-unified-origin-mpegts-remux
@@ -0,0 +1,81 @@
+99f1d34f8028c674cb10d2604a7f0117 *tests/data/fate/mov-mp4-disposition-unified-origin-mpegts-remux.mp4
+5695 tests/data/fate/mov-mp4-disposition-unified-origin-mpegts-remux.mp4
+#tb 0: 1/48000
+#media_type 0: audio
+#codec_id 0: ac3
+#sample_rate 0: 48000
+#channel_layout 0: 3
+#channel_layout_name 0: stereo
+#tb 1: 1/48000
+#media_type 1: audio
+#codec_id 1: ac3
+#sample_rate 1: 48000
+#channel_layout 1: 3
+#channel_layout_name 1: stereo
+1,          0,          0,     1536,      768, 0xa63778d4, S=1,        4
+1,       1536,       1536,     1536,      768, 0x7d577f3f
+0,       3072,       3072,     1536,      768, 0xc2867884, S=1,        4
+1,       3072,       3072,     1536,      768, 0xd86b7c8f
+0,       4608,       4608,     1536,      690, 0xa2714bf3
+1,       4608,       4608,     1536,      626, 0x09f4382f
+{
+    "programs": [
+
+    ],
+    "streams": [
+        {
+            "index": 0,
+            "disposition": {
+                "default": 1,
+                "dub": 0,
+                "original": 0,
+                "comment": 0,
+                "lyrics": 0,
+                "karaoke": 0,
+                "forced": 0,
+                "hearing_impaired": 1,
+                "visual_impaired": 0,
+                "clean_effects": 0,
+                "attached_pic": 0,
+                "timed_thumbnails": 0,
+                "captions": 1,
+                "descriptions": 0,
+                "metadata": 0,
+                "dependent": 0,
+                "still_image": 0
+            },
+            "side_data_list": [
+                {
+
+                }
+            ]
+        },
+        {
+            "index": 1,
+            "disposition": {
+                "default": 0,
+                "dub": 0,
+                "original": 0,
+                "comment": 0,
+                "lyrics": 0,
+                "karaoke": 0,
+                "forced": 0,
+                "hearing_impaired": 0,
+                "visual_impaired": 1,
+                "clean_effects": 0,
+                "attached_pic": 0,
+                "timed_thumbnails": 0,
+                "captions": 0,
+                "descriptions": 1,
+                "metadata": 0,
+                "dependent": 0,
+                "still_image": 0
+            },
+            "side_data_list": [
+                {
+
+                }
+            ]
+        }
+    ]
+}
-- 
2.31.1



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