[FFmpeg-devel] [PATCH 02/15] avformat/dashenc: allow setting fragment durations
James Almer
jamrial at gmail.com
Sat Dec 21 20:02:39 EET 2019
Implemented as as a frag_duration muxer option and key=value entry in the
adaptation_sets muxer option. It has the same syntax as the seg_duration option.
A new frag_type option is also introduced to select the kind of fragmentation.
Signed-off-by: James Almer <jamrial at gmail.com>
---
libavformat/dashenc.c | 84 ++++++++++++++++++++++++++++++++++---------
1 file changed, 68 insertions(+), 16 deletions(-)
diff --git a/libavformat/dashenc.c b/libavformat/dashenc.c
index 419043ee0b..05f2700d16 100644
--- a/libavformat/dashenc.c
+++ b/libavformat/dashenc.c
@@ -58,6 +58,13 @@ typedef enum {
SEGMENT_TYPE_NB
} SegmentType;
+enum {
+ FRAG_TYPE_NONE = 0,
+ FRAG_TYPE_EVERY_FRAME,
+ FRAG_TYPE_DURATION,
+ FRAG_TYPE_NB
+};
+
typedef struct Segment {
char file[1024];
int64_t start_pos;
@@ -72,6 +79,7 @@ typedef struct AdaptationSet {
char id[10];
char *descriptor;
int64_t seg_duration;
+ int64_t frag_duration;
enum AVMediaType media_type;
AVDictionary *metadata;
AVRational min_frame_rate, max_frame_rate;
@@ -88,6 +96,7 @@ typedef struct OutputStream {
int init_range_length;
int nb_segments, segments_size, segment_index;
int64_t seg_duration;
+ int64_t frag_duration;
Segment **segments;
int64_t first_pts, start_pts, max_pts;
int64_t last_dts, last_pts;
@@ -107,6 +116,7 @@ typedef struct OutputStream {
double availability_time_offset;
int total_pkt_size;
int muxer_overhead;
+ int frag_type;
} OutputStream;
typedef struct DASHContext {
@@ -120,6 +130,7 @@ typedef struct DASHContext {
int min_seg_duration;
#endif
int64_t seg_duration;
+ int64_t frag_duration;
int remove_at_exit;
int use_template;
int use_timeline;
@@ -153,6 +164,7 @@ typedef struct DASHContext {
int master_publish_rate;
int nr_of_streams_to_flush;
int nr_of_streams_flushed;
+ int frag_type;
} DASHContext;
static struct codec_string {
@@ -842,7 +854,7 @@ static int parse_adaptation_sets(AVFormatContext *s)
{
DASHContext *c = s->priv_data;
const char *p = c->adaptation_sets;
- enum { new_set, parse_id, parsing_streams, parse_descriptor, parse_seg_duration } state;
+ enum { new_set, parse_default, parsing_streams, parse_seg_duration, parse_frag_duration } state;
AdaptationSet *as;
int i, n, ret;
@@ -860,11 +872,11 @@ static int parse_adaptation_sets(AVFormatContext *s)
// syntax id=0,streams=0,1,2 id=1,streams=3,4 and so on
// option id=0,descriptor=descriptor_str,streams=0,1,2 and so on
- // option id=0,seg_duration=2.5,streams=0,1,2 and so on
+ // option id=0,seg_duration=2.5,frag_duration=0.5,streams=0,1,2 and so on
// descriptor is useful to the scheme defined by ISO/IEC 23009-1:2014/Amd.2:2015
// descriptor_str should be a self-closing xml tag.
- // seg_duration has the same syntax as the global seg_duration option, and has
- // precedence over it if set.
+ // seg_duration and frag_duration have the same syntax as the global options of
+ // the same name, and the former have precedence over them if set.
state = new_set;
while (*p) {
if (*p == ' ') {
@@ -881,8 +893,12 @@ static int parse_adaptation_sets(AVFormatContext *s)
p += n;
if (*p)
p++;
- state = parse_id;
+ state = parse_default;
} else if (state != new_set && av_strstart(p, "seg_duration=", &p)) {
+ state = parse_seg_duration;
+ } else if (state != new_set && av_strstart(p, "frag_duration=", &p)) {
+ state = parse_frag_duration;
+ } else if (state == parse_seg_duration || state == parse_frag_duration) {
char str[32];
int64_t usecs = 0;
@@ -898,8 +914,11 @@ static int parse_adaptation_sets(AVFormatContext *s)
return ret;
}
- as->seg_duration = usecs;
- state = parse_seg_duration;
+ if (state == parse_seg_duration)
+ as->seg_duration = usecs;
+ else
+ as->frag_duration = usecs;
+ state = parse_default;
} else if (state != new_set && av_strstart(p, "descriptor=", &p)) {
n = strcspn(p, ">") + 1; //followed by one comma, so plus 1
if (n < strlen(p)) {
@@ -911,8 +930,8 @@ static int parse_adaptation_sets(AVFormatContext *s)
p += n;
if (*p)
p++;
- state = parse_descriptor;
- } else if ((state != new_set) && av_strstart(p, "streams=", &p)) { //descriptor and duration are optional
+ state = parse_default;
+ } else if ((state != new_set) && av_strstart(p, "streams=", &p)) { //descriptor and durations are optional
state = parsing_streams;
} else if (state == parsing_streams) {
AdaptationSet *as = &c->as[c->nb_as - 1];
@@ -1203,6 +1222,10 @@ static int dash_init(AVFormatContext *s)
av_log(s, AV_LOG_WARNING, "Global SIDX option will be ignored as streaming is enabled\n");
c->global_sidx = 0;
}
+ if (c->frag_type == FRAG_TYPE_NONE && c->streaming) {
+ av_log(s, AV_LOG_VERBOSE, "Changing frag_type from none to every_frame as streaming is enabled\n");
+ c->frag_type = FRAG_TYPE_EVERY_FRAME;
+ }
av_strlcpy(c->dirname, s->url, sizeof(c->dirname));
ptr = strrchr(c->dirname, '/');
@@ -1332,19 +1355,31 @@ static int dash_init(AVFormatContext *s)
if (ret < 0)
return ret;
}
+ os->frag_duration = as->frag_duration ? as->frag_duration : c->frag_duration;
+ os->frag_type = c->frag_type;
+
+ if (os->frag_type == FRAG_TYPE_DURATION && !os->frag_duration) {
+ av_log(s, AV_LOG_WARNING, "frag_type set to duration for stream %d but no frag_duration set\n", i);
+ os->frag_type = c->streaming ? FRAG_TYPE_EVERY_FRAME : FRAG_TYPE_NONE;
+ }
if (os->segment_type == SEGMENT_TYPE_MP4) {
if (c->streaming)
- // frag_every_frame : Allows lower latency streaming
// skip_sidx : Reduce bitrate overhead
// skip_trailer : Avoids growing memory usage with time
- av_dict_set(&opts, "movflags", "frag_every_frame+dash+delay_moov+skip_sidx+skip_trailer", 0);
+ av_dict_set(&opts, "movflags", "dash+delay_moov+skip_sidx+skip_trailer", 0);
else {
if (c->global_sidx)
- av_dict_set(&opts, "movflags", "frag_custom+dash+delay_moov+global_sidx+skip_trailer", 0);
+ av_dict_set(&opts, "movflags", "dash+delay_moov+global_sidx+skip_trailer", 0);
else
- av_dict_set(&opts, "movflags", "frag_custom+dash+delay_moov+skip_trailer", 0);
+ av_dict_set(&opts, "movflags", "dash+delay_moov+skip_trailer", 0);
}
+ if (os->frag_type == FRAG_TYPE_EVERY_FRAME)
+ av_dict_set(&opts, "movflags", "+frag_every_frame", AV_DICT_APPEND);
+ else
+ av_dict_set(&opts, "movflags", "+frag_custom", AV_DICT_APPEND);
+ if (os->frag_type == FRAG_TYPE_DURATION)
+ av_dict_set_int(&opts, "frag_duration", os->frag_duration, 0);
} else {
av_dict_set_int(&opts, "cluster_time_limit", c->seg_duration / 1000, 0);
av_dict_set_int(&opts, "cluster_size_limit", 5 * 1024 * 1024, 0); // set a large cluster size limit
@@ -1764,9 +1799,21 @@ static int dash_write_packet(AVFormatContext *s, AVPacket *pkt)
sizeof(c->availability_start_time));
}
- if (!os->availability_time_offset && pkt->duration) {
- int64_t frame_duration = av_rescale_q(pkt->duration, st->time_base,
- AV_TIME_BASE_Q);
+ if (!os->availability_time_offset &&
+ (os->frag_type == FRAG_TYPE_NONE ||
+ os->frag_type == FRAG_TYPE_DURATION ||
+ (os->frag_type == FRAG_TYPE_EVERY_FRAME && pkt->duration))) {
+ int64_t frame_duration = 0;
+
+ switch (os->frag_type) {
+ case FRAG_TYPE_DURATION:
+ frame_duration = os->frag_duration;
+ break;
+ case FRAG_TYPE_EVERY_FRAME:
+ frame_duration = av_rescale_q(pkt->duration, st->time_base, AV_TIME_BASE_Q);
+ break;
+ }
+
os->availability_time_offset = ((double) os->seg_duration -
frame_duration) / AV_TIME_BASE;
}
@@ -1945,6 +1992,11 @@ static const AVOption options[] = {
{ "min_seg_duration", "minimum segment duration (in microseconds) (will be deprecated)", OFFSET(min_seg_duration), AV_OPT_TYPE_INT, { .i64 = 5000000 }, 0, INT_MAX, E },
#endif
{ "seg_duration", "segment duration (in seconds, fractional value can be set)", OFFSET(seg_duration), AV_OPT_TYPE_DURATION, { .i64 = 5000000 }, 0, INT_MAX, E },
+ { "frag_duration", "fragment duration (in seconds, fractional value can be set)", OFFSET(frag_duration), AV_OPT_TYPE_DURATION, { .i64 = 0 }, 0, INT_MAX, E },
+ { "frag_type", "set type of interval for fragments", OFFSET(frag_type), AV_OPT_TYPE_INT, {.i64 = FRAG_TYPE_NONE }, 0, FRAG_TYPE_NB - 1, E, "frag_type"},
+ { "none", "one fragment per segment", 0, AV_OPT_TYPE_CONST, {.i64 = FRAG_TYPE_NONE }, 0, UINT_MAX, E, "frag_type"},
+ { "every_frame", "fragment at every frame", 0, AV_OPT_TYPE_CONST, {.i64 = FRAG_TYPE_EVERY_FRAME }, 0, UINT_MAX, E, "frag_type"},
+ { "duration", "fragment at specific time intervals", 0, AV_OPT_TYPE_CONST, {.i64 = FRAG_TYPE_DURATION }, 0, UINT_MAX, E, "frag_type"},
{ "remove_at_exit", "remove all segments when finished", OFFSET(remove_at_exit), AV_OPT_TYPE_BOOL, { .i64 = 0 }, 0, 1, E },
{ "use_template", "Use SegmentTemplate instead of SegmentList", OFFSET(use_template), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, E },
{ "use_timeline", "Use SegmentTimeline in SegmentTemplate", OFFSET(use_timeline), AV_OPT_TYPE_BOOL, { .i64 = 1 }, 0, 1, E },
--
2.24.1
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