The current implementation of the hls_time might produce segments
with shorter duration in some cases. With the hls_min_time option
a minimal segment duration will be enforced.
Instead of changing the current behaviour of hls_time which might
break existing workflows, the new option hls_min_time will override
hls_time and enforce a minimal segment duration.
hls_time is supposed to define the minimum length of a segment,
however this is not respected in all cases when a stream has variable
GOP sizes.
Imagine a stream starts with a key frame every 10 seconds for
e.g. 30 seconds. After that, key frames will come every second. This
will result in segments that are first 10 seconds (as expected), then
1 second for some time (not as expected) and later 2 seconds (as
expected).
How to reproduce:
ffmpeg -t 30 -f lavfi -i testsrc2 -codec:v libx264 -g 250 part1.mp4
ffmpeg -t 30 -f lavfi -i testsrc2 -codec:v libx264 -g 25 part2.mp4
echo "file part1.mp4\nfile part2.mp4" > list.txt
ffmpeg -f concat -i list.txt -codec copy \
-f hls -hls_time 2 -hls_list_size 0 parts.m3u8
cat parts.m3u8
Signed-off-by: Ingo Oppermann <i...@datarhei.com>
---
doc/muxers.texi | 7 +++++++
libavformat/hlsenc.c | 27 ++++++++++++++++++++-------
2 files changed, 27 insertions(+), 7 deletions(-)
diff --git a/doc/muxers.texi b/doc/muxers.texi
index 04b7f20b7e..e058a8f8c0 100644
--- a/doc/muxers.texi
+++ b/doc/muxers.texi
@@ -1929,6 +1929,13 @@ Set the target segment length. Default value is 2.
see @ref{time duration syntax,,the Time duration section in the
ffmpeg-utils(1) manual,ffmpeg-utils}.
Segment will be cut on the next key frame after this time has passed.
+@item hls_min_time @var{duration}
+Set the minimum target segment length. Default value is 0.
+
+@var{duration} must be a time duration specification,
+see @ref{time duration syntax,,the Time duration section in the
ffmpeg-utils(1) manual,ffmpeg-utils}.
+Segment will be at least this long and will be cut at the following key frame.
If set, it will override @option{hls_time}.
+
@item hls_list_size @var{size}
Set the maximum number of playlist entries. If set to 0 the list file
will contain all the segments. Default value is 5.
diff --git a/libavformat/hlsenc.c b/libavformat/hlsenc.c
index 6148685f40..5fc215fdce 100644
--- a/libavformat/hlsenc.c
+++ b/libavformat/hlsenc.c
@@ -204,6 +204,7 @@ typedef struct HLSContext {
uint32_t start_sequence_source_type; // enum StartSequenceSourceType
int64_t time; // Set by a private option.
+ int64_t min_time; // Set by a private option.
int64_t init_time; // Set by a private option.
int max_nb_segments; // Set by a private option.
int hls_delete_threshold; // Set by a private option.
@@ -2474,7 +2475,7 @@ static int hls_write_packet(AVFormatContext *s, AVPacket
*pkt)
HLSContext *hls = s->priv_data;
AVFormatContext *oc = NULL;
AVStream *st = s->streams[pkt->stream_index];
- int64_t end_pts = 0;
+ int64_t end_pts = 0, current_pts;
int is_ref_pkt = 1;
int ret = 0, can_split = 1, i, j;
int stream_index = 0;
@@ -2515,11 +2516,16 @@ static int hls_write_packet(AVFormatContext *s,
AVPacket *pkt)
end_pts = hls->recording_time * vs->number;
if (vs->sequence - vs->nb_entries > hls->start_sequence && hls->init_time
> 0) {
- /* reset end_pts, hls->recording_time at end of the init hls list */
- int64_t init_list_dur = hls->init_time * vs->nb_entries;
- int64_t after_init_list_dur = (vs->sequence - hls->start_sequence -
vs->nb_entries) * hls->time;
- hls->recording_time = hls->time;
- end_pts = init_list_dur + after_init_list_dur ;
+ if (hls->min_time > 0) {
+ hls->recording_time = hls->min_time;
+ hls->init_time = 0;
+ } else {
+ /* reset end_pts, hls->recording_time at end of the init hls list
*/
+ int64_t init_list_dur = hls->init_time * vs->nb_entries;
+ int64_t after_init_list_dur = (vs->sequence - hls->start_sequence
- vs->nb_entries) * hls->time;
+ hls->recording_time = hls->time;
+ end_pts = init_list_dur + after_init_list_dur;
+ }
}
if (vs->start_pts == AV_NOPTS_VALUE) {
@@ -2559,8 +2565,14 @@ static int hls_write_packet(AVFormatContext *s, AVPacket
*pkt)
}
}
+ current_pts = pkt->pts - vs->start_pts;
+ if (hls->min_time > 0 && hls->init_time == 0) {
+ current_pts = pkt->pts - vs->end_pts;
+ end_pts = hls->min_time;
+ }
+
can_split = can_split && (pkt->pts - vs->end_pts > 0);
- if (vs->packets_written && can_split && av_compare_ts(pkt->pts -
vs->start_pts, st->time_base,
+ if (vs->packets_written && can_split && av_compare_ts(current_pts,
st->time_base,
end_pts,
AV_TIME_BASE_Q) >= 0) {
int64_t new_start_pos;
int byterange_mode = (hls->flags & HLS_SINGLE_FILE) ||
(hls->max_seg_size > 0);
@@ -3182,6 +3194,7 @@ static int hls_init(AVFormatContext *s)
static const AVOption options[] = {
{"start_number", "set first number in the sequence",
OFFSET(start_sequence),AV_OPT_TYPE_INT64, {.i64 = 0}, 0, INT64_MAX, E},
{"hls_time", "set segment length", OFFSET(time),
AV_OPT_TYPE_DURATION, {.i64 = 2000000}, 0, INT64_MAX, E},
+ {"hls_min_time", "set minimum segment length",
OFFSET(min_time), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, INT64_MAX, E},
{"hls_init_time", "set segment length at init list",
OFFSET(init_time), AV_OPT_TYPE_DURATION, {.i64 = 0}, 0, INT64_MAX, E},
{"hls_list_size", "set maximum number of playlist entries",
OFFSET(max_nb_segments), AV_OPT_TYPE_INT, {.i64 = 5}, 0, INT_MAX, E},
{"hls_delete_threshold", "set number of unreferenced segments to keep
before deleting", OFFSET(hls_delete_threshold), AV_OPT_TYPE_INT, {.i64 =
1}, 1, INT_MAX, E},
base-commit: 3380c0d27df1e07f009e114da98fb8033c2ce33d
--
2.39.5 (Apple Git-154)
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