revert

Re-apply [FFmpeg-devel] [PATCH] lavf/hlsenc: add -hls_start_time to emit
EXT-X-START:TIME-OFFSET

doc/muxers.texi

@@ -1125,6 +1125,9 @@ are always written into temporary file regardless of this flag if @code{master_p
 Emit @code{#EXT-X-PLAYLIST-TYPE:EVENT} in the m3u8 header. Forces
 @option{hls_list_size} to 0; the playlist can only be appended to.
 
+@item hls_start_time @var{offset}
+Emit @code{#EXT-X-START:TIME-OFFSET} in the m3u8 header.
+
 @item hls_playlist_type vod
 Emit @code{#EXT-X-PLAYLIST-TYPE:VOD} in the m3u8 header. Forces
 @option{hls_list_size} to 0; the playlist must not change.

libavformat/dashenc.c

@@ -540,7 +540,7 @@ static void write_hls_media_playlist(OutputStream *os, AVFormatContext *s,
     }
 
     ff_hls_write_playlist_header(c->m3u8_out, 6, -1, target_duration,
-                                 start_number, PLAYLIST_TYPE_NONE, 0);
+                                 start_number, PLAYLIST_TYPE_NONE, 0, -1);
 
     ff_hls_write_init_file(c->m3u8_out, os->initfile, c->single_file,
                            os->init_range_length, os->init_start_pos);

libavformat/hlsenc.c

@@ -22,6 +22,7 @@
 
 #include "config.h"
 #include "config_components.h"
+#include <float.h>
 #include <stdint.h>
 #include <time.h>
 #if HAVE_UNISTD_H
@@ -194,6 +195,8 @@ typedef struct HLSContext {
     const AVClass *class;  // Class for private options.
     int64_t start_sequence;
     uint32_t start_sequence_source_type;  // enum StartSequenceSourceType
+    
+    double start_offset;
 
     int64_t time;          // Set by a private option.
     int64_t init_time;     // Set by a private option.
@@ -1574,7 +1577,7 @@ static int hls_window(AVFormatContext *s, int last, VariantStream *vs)
         hls->version = 4;
     }
 
-    if (hls->flags & HLS_INDEPENDENT_SEGMENTS) {
+    if ((hls->flags & HLS_INDEPENDENT_SEGMENTS) || (hls->start_offset>=0)) {
         hls->version = 6;
     }
 
@@ -1602,7 +1605,7 @@ static int hls_window(AVFormatContext *s, int last, VariantStream *vs)
 
     vs->discontinuity_set = 0;
     ff_hls_write_playlist_header(byterange_mode ? hls->m3u8_out : vs->out, hls->version, hls->allowcache,
-                                 target_duration, sequence, hls->pl_type, hls->flags & HLS_I_FRAMES_ONLY);
+                                 target_duration, sequence, hls->pl_type, hls->flags & HLS_I_FRAMES_ONLY,hls->start_offset);
 
     if ((hls->flags & HLS_DISCONT_START) && sequence==hls->start_sequence && vs->discontinuity_set==0) {
         avio_printf(byterange_mode ? hls->m3u8_out : vs->out, "#EXT-X-DISCONTINUITY\n");
@@ -1654,7 +1657,7 @@ static int hls_window(AVFormatContext *s, int last, VariantStream *vs)
             goto fail;
         }
         ff_hls_write_playlist_header(hls->sub_m3u8_out, hls->version, hls->allowcache,
-                                     target_duration, sequence, PLAYLIST_TYPE_NONE, 0);
+                                     target_duration, sequence, PLAYLIST_TYPE_NONE, 0,hls->start_offset);
         for (en = vs->segments; en; en = en->next) {
             ret = ff_hls_write_file_entry(hls->sub_m3u8_out, 0, byterange_mode,
                                           en->duration, 0, en->size, en->pos,
@@ -2627,7 +2630,7 @@ static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
         }
 
         // if we're building a VOD playlist, skip writing the manifest multiple times, and just wait until the end
-        if (hls->pl_type != PLAYLIST_TYPE_VOD) {
+        //if (hls->pl_type != PLAYLIST_TYPE_VOD) {
             if ((ret = hls_window(s, 0, vs)) < 0) {
                 av_log(s, AV_LOG_WARNING, "upload playlist failed, will retry with a new http session.\n");
                 ff_format_io_close(s, &vs->out);
@@ -2636,7 +2639,7 @@ static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
                     return ret;
                 }
             }
-        }
+        //}
 
         if (hls->resend_init_file && hls->segment_type == SEGMENT_TYPE_FMP4) {
             ret = hls_init_file_resend(s, vs);
@@ -3126,6 +3129,7 @@ static const AVOption options[] = {
     {"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},
     {"hls_vtt_options","set hls vtt list of options for the container format used for hls", OFFSET(vtt_format_options_str), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,    E},
+    {"hls_start_time", "set EXT-X-START:TIME-OFFSET",           OFFSET(start_offset),    AV_OPT_TYPE_DOUBLE,  {.dbl = -1},     -1, DBL_MAX, E},
     {"hls_allow_cache", "explicitly set whether the client MAY (1) or MUST NOT (0) cache media segments", OFFSET(allowcache), AV_OPT_TYPE_INT, {.i64 = -1}, INT_MIN, INT_MAX, E},
     {"hls_base_url",  "url to prepend to each playlist entry",   OFFSET(baseurl), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       E},
     {"hls_segment_filename", "filename template for segment files", OFFSET(segment_filename),   AV_OPT_TYPE_STRING, {.str = NULL},            0,       0,         E},

libavformat/hlsplaylist.c

@@ -101,7 +101,7 @@ void ff_hls_write_stream_info(AVStream *st, AVIOContext *out, int bandwidth,
 
 void ff_hls_write_playlist_header(AVIOContext *out, int version, int allowcache,
                                   int target_duration, int64_t sequence,
-                                  uint32_t playlist_type, int iframe_mode)
+                                  uint32_t playlist_type, int iframe_mode, double start_offset)
 {
     if (!out)
         return;
@@ -109,6 +109,9 @@ void ff_hls_write_playlist_header(AVIOContext *out, int version, int allowcache,
     if (allowcache == 0 || allowcache == 1) {
         avio_printf(out, "#EXT-X-ALLOW-CACHE:%s\n", allowcache == 0 ? "NO" : "YES");
     }
+    if(start_offset>=0){
+        avio_printf(out, "#EXT-X-START:TIME-OFFSET=%f\n", start_offset);
+    }
     avio_printf(out, "#EXT-X-TARGETDURATION:%d\n", target_duration);
     avio_printf(out, "#EXT-X-MEDIA-SEQUENCE:%"PRId64"\n", sequence);
     av_log(NULL, AV_LOG_VERBOSE, "EXT-X-MEDIA-SEQUENCE:%"PRId64"\n", sequence);

libavformat/hlsplaylist.h

@@ -48,7 +48,7 @@ void ff_hls_write_stream_info(AVStream *st, AVIOContext *out, int bandwidth,
                               const char *sgroup);
 void ff_hls_write_playlist_header(AVIOContext *out, int version, int allowcache,
                                   int target_duration, int64_t sequence,
-                                  uint32_t playlist_type, int iframe_mode);
+                                  uint32_t playlist_type, int iframe_mode, double start_offset);
 void ff_hls_write_init_file(AVIOContext *out, const char *filename,
                             int byterange_mode, int64_t size, int64_t pos);
 int ff_hls_write_file_entry(AVIOContext *out, int insert_discont,