[FFmpeg-devel] [PATCH v3 1/1] avformat/hlsenc: closed caption tags in the master playlist
vdixit at akamai.com
vdixit at akamai.com
Tue Jan 23 07:21:20 EET 2018
From: Vishwanath Dixit <vdixit at akamai.com>
---
doc/muxers.texi | 37 +++++++++++
libavformat/dashenc.c | 2 +-
libavformat/hlsenc.c | 155 +++++++++++++++++++++++++++++++++++++++++++++-
libavformat/hlsplaylist.c | 5 +-
libavformat/hlsplaylist.h | 2 +-
5 files changed, 196 insertions(+), 5 deletions(-)
diff --git a/doc/muxers.texi b/doc/muxers.texi
index b060c4f..d9a5cc0 100644
--- a/doc/muxers.texi
+++ b/doc/muxers.texi
@@ -901,6 +901,43 @@ and they are mapped to the two video only variant streams with audio group names
By default, a single hls variant containing all the encoded streams is created.
+ at item cc_stream_map
+Map string which specifies different closed captions groups and their
+attributes. The closed captions stream groups are separated by space.
+Expected string format is like this
+"ccgroup:<group name>,instreamid:<INSTREAM-ID>,language:<language code> ....".
+'ccgroup' and 'instreamid' are mandatory attributes. 'language' is an optional
+attribute.
+The closed captions groups configured using this option are mapped to different
+variant streams by providing the same 'ccgroup' name in the
+ at code{var_stream_map} string. If @code{var_stream_map} is not set, then the
+first available ccgroup in @code{cc_stream_map} is mapped to the output variant
+stream. The examples for these two use cases are given below.
+
+ at example
+ffmpeg -re -i in.ts -b:v 1000k -b:a 64k -a53cc 1 -f hls \
+ -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en" \
+ -master_pl_name master.m3u8 \
+ http://example.com/live/out.m3u8
+ at end example
+This example adds @code{#EXT-X-MEDIA} tag with @code{TYPE=CLOSED-CAPTIONS} in
+the master playlist with group name 'cc', langauge 'en' (english) and
+INSTREAM-ID 'CC1'. Also, it adds @code{CLOSED-CAPTIONS} attribute with group
+name 'cc' for the output variant stream.
+ at example
+ffmpeg -re -i in.ts -b:v:0 1000k -b:v:1 256k -b:a:0 64k -b:a:1 32k \
+ -a53cc:0 1 -a53cc:1 1\
+ -map 0:v -map 0:a -map 0:v -map 0:a -f hls \
+ -cc_stream_map "ccgroup:cc,instreamid:CC1,language:en ccgroup:cc,instreamid:CC2,language:sp" \
+ -var_stream_map "v:0,a:0,ccgroup:cc v:1,a:1,ccgroup:cc" \
+ -master_pl_name master.m3u8 \
+ http://example.com/live/out_%v.m3u8
+ at end example
+This example adds two @code{#EXT-X-MEDIA} tags with @code{TYPE=CLOSED-CAPTIONS} in
+the master playlist for the INSTREAM-IDs 'CC1' and 'CC2'. Also, it adds
+ at code{CLOSED-CAPTIONS} attribute with group name 'cc' for the two output variant
+streams.
+
@item master_pl_name
Create HLS master playlist with the given name.
diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c
index 39d0afe..5ece100 100644
--- a/libavformat/dashenc.c
+++ b/libavformat/dashenc.c
@@ -820,7 +820,7 @@ static int write_manifest(AVFormatContext *s, int final)
stream_bitrate += max_audio_bitrate;
}
get_hls_playlist_name(playlist_file, sizeof(playlist_file), NULL, i);
- ff_hls_write_stream_info(st, out, stream_bitrate, playlist_file, agroup, NULL);
+ ff_hls_write_stream_info(st, out, stream_bitrate, playlist_file, agroup, NULL, NULL);
}
avio_close(out);
if (use_rename)
diff --git a/libavformat/hlsenc.c b/libavformat/hlsenc.c
index 42e437f..aab21f2 100644
--- a/libavformat/hlsenc.c
+++ b/libavformat/hlsenc.c
@@ -152,9 +152,16 @@ typedef struct VariantStream {
unsigned int nb_streams;
int m3u8_created; /* status of media play-list creation */
char *agroup; /* audio group name */
+ char *ccgroup; /* closed caption group name */
char *baseurl;
} VariantStream;
+typedef struct ClosedCaptionsStream {
+ char *ccgroup; /* closed caption group name */
+ char *instreamid; /* closed captions INSTREAM-ID */
+ char *language; /* closed captions langauge */
+} ClosedCaptionsStream;
+
typedef struct HLSContext {
const AVClass *class; // Class for private options.
int64_t start_sequence;
@@ -203,11 +210,14 @@ typedef struct HLSContext {
VariantStream *var_streams;
unsigned int nb_varstreams;
+ ClosedCaptionsStream *cc_streams;
+ unsigned int nb_ccstreams;
int master_m3u8_created; /* status of master play-list creation */
char *master_m3u8_url; /* URL of the master m3u8 file */
int version; /* HLS version */
char *var_stream_map; /* user specified variant stream map string */
+ char *cc_stream_map; /* user specified closed caption streams map string */
char *master_pl_name;
unsigned int master_publish_rate;
int http_persistent;
@@ -1167,7 +1177,8 @@ static int create_master_playlist(AVFormatContext *s,
AVDictionary *options = NULL;
unsigned int i, j;
int m3u8_name_size, ret, bandwidth;
- char *m3u8_rel_name;
+ char *m3u8_rel_name, *ccgroup;
+ ClosedCaptionsStream *ccs;
input_vs->m3u8_created = 1;
if (!hls->master_m3u8_created) {
@@ -1194,6 +1205,16 @@ static int create_master_playlist(AVFormatContext *s,
ff_hls_write_playlist_version(hls->m3u8_out, hls->version);
+ for (i = 0; i < hls->nb_ccstreams; i++) {
+ ccs = &(hls->cc_streams[i]);
+ avio_printf(hls->m3u8_out, "#EXT-X-MEDIA:TYPE=CLOSED-CAPTIONS");
+ avio_printf(hls->m3u8_out, ",GROUP-ID=\"%s\"", ccs->ccgroup);
+ avio_printf(hls->m3u8_out, ",NAME=\"%s\"", ccs->instreamid);
+ if (ccs->language)
+ avio_printf(hls->m3u8_out, ",LANGUAGE=\"%s\"", ccs->language);
+ avio_printf(hls->m3u8_out, ",INSTREAM-ID=\"%s\"\n", ccs->instreamid);
+ }
+
/* For audio only variant streams add #EXT-X-MEDIA tag with attributes*/
for (i = 0; i < hls->nb_varstreams; i++) {
vs = &(hls->var_streams[i]);
@@ -1278,8 +1299,23 @@ static int create_master_playlist(AVFormatContext *s,
bandwidth += aud_st->codecpar->bit_rate;
bandwidth += bandwidth / 10;
+ ccgroup = NULL;
+ if (vid_st && vs->ccgroup) {
+ /* check if this group name is available in the cc map string */
+ for (j = 0; j < hls->nb_ccstreams; j++) {
+ ccs = &(hls->cc_streams[j]);
+ if (!av_strcasecmp(ccs->ccgroup, vs->ccgroup)) {
+ ccgroup = vs->ccgroup;
+ break;
+ }
+ }
+ if (j == hls->nb_ccstreams)
+ av_log(NULL, AV_LOG_WARNING, "mapping ccgroup %s not found\n",
+ vs->ccgroup);
+ }
+
ff_hls_write_stream_info(vid_st, hls->m3u8_out, bandwidth, m3u8_rel_name,
- aud_st ? vs->agroup : NULL, vs->codec_attr);
+ aud_st ? vs->agroup : NULL, vs->codec_attr, ccgroup);
av_freep(&m3u8_rel_name);
}
@@ -1766,6 +1802,11 @@ static int parse_variant_stream_mapstring(AVFormatContext *s)
if (!vs->agroup)
return AVERROR(ENOMEM);
continue;
+ } else if (av_strstart(keyval, "ccgroup:", &val)) {
+ vs->ccgroup = av_strdup(val);
+ if (!vs->ccgroup)
+ return AVERROR(ENOMEM);
+ continue;
} else if (av_strstart(keyval, "v:", &val)) {
codec_type = AVMEDIA_TYPE_VIDEO;
} else if (av_strstart(keyval, "a:", &val)) {
@@ -1796,9 +1837,94 @@ static int parse_variant_stream_mapstring(AVFormatContext *s)
return 0;
}
+static int parse_cc_stream_mapstring(AVFormatContext *s)
+{
+ HLSContext *hls = s->priv_data;
+ int nb_ccstreams;
+ char *p, *q, *saveptr1, *saveptr2, *ccstr, *keyval;
+ const char *val;
+ ClosedCaptionsStream *ccs;
+
+ p = av_strdup(hls->cc_stream_map);
+ q = p;
+ while(av_strtok(q, " \t", &saveptr1)) {
+ q = NULL;
+ hls->nb_ccstreams++;
+ }
+ av_freep(&p);
+
+ hls->cc_streams = av_mallocz(sizeof(*hls->cc_streams) * hls->nb_ccstreams);
+ if (!hls->cc_streams)
+ return AVERROR(ENOMEM);
+
+ p = hls->cc_stream_map;
+ nb_ccstreams = 0;
+ while (ccstr = av_strtok(p, " \t", &saveptr1)) {
+ p = NULL;
+
+ if (nb_ccstreams < hls->nb_ccstreams)
+ ccs = &(hls->cc_streams[nb_ccstreams++]);
+ else
+ return AVERROR(EINVAL);
+
+ while (keyval = av_strtok(ccstr, ",", &saveptr2)) {
+ ccstr = NULL;
+
+ if (av_strstart(keyval, "ccgroup:", &val)) {
+ ccs->ccgroup = av_strdup(val);
+ if (!ccs->ccgroup)
+ return AVERROR(ENOMEM);
+ } else if (av_strstart(keyval, "instreamid:", &val)) {
+ ccs->instreamid = av_strdup(val);
+ if (!ccs->instreamid)
+ return AVERROR(ENOMEM);
+ } else if (av_strstart(keyval, "language:", &val)) {
+ ccs->language = av_strdup(val);
+ if (!ccs->language)
+ return AVERROR(ENOMEM);
+ } else {
+ av_log(s, AV_LOG_ERROR, "Invalid keyval %s\n", keyval);
+ return AVERROR(EINVAL);
+ }
+ }
+
+ if (!ccs->ccgroup || !ccs->instreamid) {
+ av_log(s, AV_LOG_ERROR, "Insufficient parameters in cc stream map string\n");
+ return AVERROR(EINVAL);
+ }
+
+ if (av_strstart(ccs->instreamid, "CC", &val)) {
+ if(atoi(val) < 1 || atoi(val) > 4) {
+ av_log(s, AV_LOG_ERROR, "Invalid instream ID CC index %d in %s, range 1-4\n",
+ atoi(val), ccs->instreamid);
+ return AVERROR(EINVAL);
+ }
+ } else if (av_strstart(ccs->instreamid, "SERVICE", &val)) {
+ if(atoi(val) < 1 || atoi(val) > 63) {
+ av_log(s, AV_LOG_ERROR, "Invalid instream ID SERVICE index %d in %s, range 1-63 \n",
+ atoi(val), ccs->instreamid);
+ return AVERROR(EINVAL);
+ }
+ } else {
+ av_log(s, AV_LOG_ERROR, "Invalid instream ID %s, supported are CCn or SERIVICEn\n",
+ ccs->instreamid);
+ return AVERROR(EINVAL);
+ }
+ }
+
+ return 0;
+}
+
static int update_variant_stream_info(AVFormatContext *s) {
HLSContext *hls = s->priv_data;
unsigned int i;
+ int ret = 0;
+
+ if (hls->cc_stream_map) {
+ ret = parse_cc_stream_mapstring(s);
+ if (ret < 0)
+ return ret;
+ }
if (hls->var_stream_map) {
return parse_variant_stream_mapstring(s);
@@ -1816,6 +1942,13 @@ static int update_variant_stream_info(AVFormatContext *s) {
if (!hls->var_streams[0].streams)
return AVERROR(ENOMEM);
+ //by default, the first available ccgroup is mapped to the variant stream
+ if (hls->nb_ccstreams) {
+ hls->var_streams[0].ccgroup = av_strdup(hls->cc_streams[0].ccgroup);
+ if (!hls->var_streams[0].ccgroup)
+ return AVERROR(ENOMEM);
+ }
+
for (i = 0; i < s->nb_streams; i++)
hls->var_streams[0].streams[i] = s->streams[i];
}
@@ -2192,13 +2325,22 @@ failed:
av_freep(&vs->m3u8_name);
av_freep(&vs->streams);
av_freep(&vs->agroup);
+ av_freep(&vs->ccgroup);
av_freep(&vs->baseurl);
}
+ for (i = 0; i < hls->nb_ccstreams; i++) {
+ ClosedCaptionsStream *ccs = &hls->cc_streams[i];
+ av_freep(&ccs->ccgroup);
+ av_freep(&ccs->instreamid);
+ av_freep(&ccs->language);
+ }
+
ff_format_io_close(s, &hls->m3u8_out);
ff_format_io_close(s, &hls->sub_m3u8_out);
av_freep(&hls->key_basename);
av_freep(&hls->var_streams);
+ av_freep(&hls->cc_streams);
av_freep(&hls->master_m3u8_url);
return 0;
}
@@ -2535,13 +2677,21 @@ fail:
av_freep(&vs->vtt_m3u8_name);
av_freep(&vs->streams);
av_freep(&vs->agroup);
+ av_freep(&vs->ccgroup);
av_freep(&vs->baseurl);
if (vs->avf)
avformat_free_context(vs->avf);
if (vs->vtt_avf)
avformat_free_context(vs->vtt_avf);
}
+ for (i = 0; i < hls->nb_ccstreams; i++) {
+ ClosedCaptionsStream *ccs = &hls->cc_streams[i];
+ av_freep(&ccs->ccgroup);
+ av_freep(&ccs->instreamid);
+ av_freep(&ccs->language);
+ }
av_freep(&hls->var_streams);
+ av_freep(&hls->cc_streams);
av_freep(&hls->master_m3u8_url);
}
@@ -2601,6 +2751,7 @@ static const AVOption options[] = {
{"datetime", "current datetime as YYYYMMDDhhmmss", 0, AV_OPT_TYPE_CONST, {.i64 = HLS_START_SEQUENCE_AS_FORMATTED_DATETIME }, INT_MIN, INT_MAX, E, "start_sequence_source_type" },
{"http_user_agent", "override User-Agent field in HTTP header", OFFSET(user_agent), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
{"var_stream_map", "Variant stream map string", OFFSET(var_stream_map), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
+ {"cc_stream_map", "Closed captions stream map string", OFFSET(cc_stream_map), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
{"master_pl_name", "Create HLS master playlist with this name", OFFSET(master_pl_name), AV_OPT_TYPE_STRING, {.str = NULL}, 0, 0, E},
{"master_pl_publish_rate", "Publish master play list every after this many segment intervals", OFFSET(master_publish_rate), AV_OPT_TYPE_INT, {.i64 = 0}, 0, UINT_MAX, E},
{"http_persistent", "Use persistent HTTP connections", OFFSET(http_persistent), AV_OPT_TYPE_BOOL, {.i64 = 0 }, 0, 1, E },
diff --git a/libavformat/hlsplaylist.c b/libavformat/hlsplaylist.c
index b8a3a14..efcbff0 100644
--- a/libavformat/hlsplaylist.c
+++ b/libavformat/hlsplaylist.c
@@ -47,7 +47,8 @@ void ff_hls_write_audio_rendition(AVIOContext *out, char *agroup,
void ff_hls_write_stream_info(AVStream *st, AVIOContext *out,
int bandwidth, char *filename, char *agroup,
- char *codecs) {
+ char *codecs, char *ccgroup) {
+
if (!out || !filename)
return;
@@ -65,6 +66,8 @@ void ff_hls_write_stream_info(AVStream *st, AVIOContext *out,
avio_printf(out, ",CODECS=\"%s\"", codecs);
if (agroup && strlen(agroup) > 0)
avio_printf(out, ",AUDIO=\"group_%s\"", agroup);
+ if (ccgroup && strlen(ccgroup) > 0)
+ avio_printf(out, ",CLOSED-CAPTIONS=\"%s\"", ccgroup);
avio_printf(out, "\n%s\n\n", filename);
}
diff --git a/libavformat/hlsplaylist.h b/libavformat/hlsplaylist.h
index 7532e37..5054b01 100644
--- a/libavformat/hlsplaylist.h
+++ b/libavformat/hlsplaylist.h
@@ -41,7 +41,7 @@ void ff_hls_write_audio_rendition(AVIOContext *out, char *agroup,
char *filename, int name_id, int is_default);
void ff_hls_write_stream_info(AVStream *st, AVIOContext *out,
int bandwidth, char *filename, char *agroup,
- char *codecs);
+ char *codecs, char *ccgroup);
void ff_hls_write_playlist_header(AVIOContext *out, int version, int allowcache,
int target_duration, int64_t sequence,
uint32_t playlist_type);
--
1.9.1
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