yading@11: /*
yading@11:  * Apple HTTP Live Streaming segmenter
yading@11:  * Copyright (c) 2012, Luca Barbato
yading@11:  *
yading@11:  * This file is part of FFmpeg.
yading@11:  *
yading@11:  * FFmpeg is free software; you can redistribute it and/or
yading@11:  * modify it under the terms of the GNU Lesser General Public
yading@11:  * License as published by the Free Software Foundation; either
yading@11:  * version 2.1 of the License, or (at your option) any later version.
yading@11:  *
yading@11:  * FFmpeg is distributed in the hope that it will be useful,
yading@11:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
yading@11:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
yading@11:  * Lesser General Public License for more details.
yading@11:  *
yading@11:  * You should have received a copy of the GNU Lesser General Public
yading@11:  * License along with FFmpeg; if not, write to the Free Software
yading@11:  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
yading@11:  */
yading@11: 
yading@11: #include <float.h>
yading@11: 
yading@11: #include "libavutil/mathematics.h"
yading@11: #include "libavutil/parseutils.h"
yading@11: #include "libavutil/avstring.h"
yading@11: #include "libavutil/opt.h"
yading@11: #include "libavutil/log.h"
yading@11: 
yading@11: #include "avformat.h"
yading@11: #include "internal.h"
yading@11: 
yading@11: typedef struct ListEntry {
yading@11:     char  name[1024];
yading@11:     int   duration;
yading@11:     struct ListEntry *next;
yading@11: } ListEntry;
yading@11: 
yading@11: typedef struct HLSContext {
yading@11:     const AVClass *class;  // Class for private options.
yading@11:     unsigned number;
yading@11:     int64_t sequence;
yading@11:     AVOutputFormat *oformat;
yading@11:     AVFormatContext *avf;
yading@11:     float time;            // Set by a private option.
yading@11:     int  size;             // Set by a private option.
yading@11:     int  wrap;             // Set by a private option.
yading@11:     int64_t recording_time;
yading@11:     int has_video;
yading@11:     int64_t start_pts;
yading@11:     int64_t end_pts;
yading@11:     int64_t duration;      ///< last segment duration computed so far, in seconds
yading@11:     int nb_entries;
yading@11:     ListEntry *list;
yading@11:     ListEntry *end_list;
yading@11:     char *basename;
yading@11:     AVIOContext *pb;
yading@11: } HLSContext;
yading@11: 
yading@11: static int hls_mux_init(AVFormatContext *s)
yading@11: {
yading@11:     HLSContext *hls = s->priv_data;
yading@11:     AVFormatContext *oc;
yading@11:     int i;
yading@11: 
yading@11:     hls->avf = oc = avformat_alloc_context();
yading@11:     if (!oc)
yading@11:         return AVERROR(ENOMEM);
yading@11: 
yading@11:     oc->oformat            = hls->oformat;
yading@11:     oc->interrupt_callback = s->interrupt_callback;
yading@11: 
yading@11:     for (i = 0; i < s->nb_streams; i++) {
yading@11:         AVStream *st;
yading@11:         if (!(st = avformat_new_stream(oc, NULL)))
yading@11:             return AVERROR(ENOMEM);
yading@11:         avcodec_copy_context(st->codec, s->streams[i]->codec);
yading@11:         st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
yading@11:     }
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int append_entry(HLSContext *hls, uint64_t duration)
yading@11: {
yading@11:     ListEntry *en = av_malloc(sizeof(*en));
yading@11: 
yading@11:     if (!en)
yading@11:         return AVERROR(ENOMEM);
yading@11: 
yading@11:     av_strlcpy(en->name, av_basename(hls->avf->filename), sizeof(en->name));
yading@11: 
yading@11:     en->duration = duration;
yading@11:     en->next     = NULL;
yading@11: 
yading@11:     if (!hls->list)
yading@11:         hls->list = en;
yading@11:     else
yading@11:         hls->end_list->next = en;
yading@11: 
yading@11:     hls->end_list = en;
yading@11: 
yading@11:     if (hls->nb_entries >= hls->size) {
yading@11:         en = hls->list;
yading@11:         hls->list = en->next;
yading@11:         av_free(en);
yading@11:     } else
yading@11:         hls->nb_entries++;
yading@11: 
yading@11:     hls->sequence++;
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static void free_entries(HLSContext *hls)
yading@11: {
yading@11:     ListEntry *p = hls->list, *en;
yading@11: 
yading@11:     while(p) {
yading@11:         en = p;
yading@11:         p = p->next;
yading@11:         av_free(en);
yading@11:     }
yading@11: }
yading@11: 
yading@11: static int hls_window(AVFormatContext *s, int last)
yading@11: {
yading@11:     HLSContext *hls = s->priv_data;
yading@11:     ListEntry *en;
yading@11:     int target_duration = 0;
yading@11:     int ret = 0;
yading@11: 
yading@11:     if ((ret = avio_open2(&hls->pb, s->filename, AVIO_FLAG_WRITE,
yading@11:                           &s->interrupt_callback, NULL)) < 0)
yading@11:         goto fail;
yading@11: 
yading@11:     for (en = hls->list; en; en = en->next) {
yading@11:         if (target_duration < en->duration)
yading@11:             target_duration = en->duration;
yading@11:     }
yading@11: 
yading@11:     avio_printf(hls->pb, "#EXTM3U\n");
yading@11:     avio_printf(hls->pb, "#EXT-X-VERSION:3\n");
yading@11:     avio_printf(hls->pb, "#EXT-X-TARGETDURATION:%d\n", target_duration);
yading@11:     avio_printf(hls->pb, "#EXT-X-MEDIA-SEQUENCE:%"PRId64"\n",
yading@11:                 FFMAX(0, hls->sequence - hls->size));
yading@11: 
yading@11:     for (en = hls->list; en; en = en->next) {
yading@11:         avio_printf(hls->pb, "#EXTINF:%d,\n", en->duration);
yading@11:         avio_printf(hls->pb, "%s\n", en->name);
yading@11:     }
yading@11: 
yading@11:     if (last)
yading@11:         avio_printf(hls->pb, "#EXT-X-ENDLIST\n");
yading@11: 
yading@11: fail:
yading@11:     avio_closep(&hls->pb);
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: static int hls_start(AVFormatContext *s)
yading@11: {
yading@11:     HLSContext *c = s->priv_data;
yading@11:     AVFormatContext *oc = c->avf;
yading@11:     int err = 0;
yading@11: 
yading@11:     if (c->wrap)
yading@11:         c->number %= c->wrap;
yading@11: 
yading@11:     if (av_get_frame_filename(oc->filename, sizeof(oc->filename),
yading@11:                               c->basename, c->number++) < 0) {
yading@11:         av_log(oc, AV_LOG_ERROR, "Invalid segment filename template '%s'\n", c->basename);
yading@11:         return AVERROR(EINVAL);
yading@11:     }
yading@11: 
yading@11:     if ((err = avio_open2(&oc->pb, oc->filename, AVIO_FLAG_WRITE,
yading@11:                           &s->interrupt_callback, NULL)) < 0)
yading@11:         return err;
yading@11: 
yading@11:     if (oc->oformat->priv_class && oc->priv_data)
yading@11:         av_opt_set(oc->priv_data, "mpegts_flags", "resend_headers", 0);
yading@11: 
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: static int hls_write_header(AVFormatContext *s)
yading@11: {
yading@11:     HLSContext *hls = s->priv_data;
yading@11:     int ret, i;
yading@11:     char *p;
yading@11:     const char *pattern = "%d.ts";
yading@11:     int basename_size = strlen(s->filename) + strlen(pattern) + 1;
yading@11: 
yading@11:     hls->number      = 0;
yading@11: 
yading@11:     hls->recording_time = hls->time * AV_TIME_BASE;
yading@11:     hls->start_pts      = AV_NOPTS_VALUE;
yading@11: 
yading@11:     for (i = 0; i < s->nb_streams; i++)
yading@11:         hls->has_video +=
yading@11:             s->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO;
yading@11: 
yading@11:     if (hls->has_video > 1)
yading@11:         av_log(s, AV_LOG_WARNING,
yading@11:                "More than a single video stream present, "
yading@11:                "expect issues decoding it.\n");
yading@11: 
yading@11:     hls->oformat = av_guess_format("mpegts", NULL, NULL);
yading@11: 
yading@11:     if (!hls->oformat) {
yading@11:         ret = AVERROR_MUXER_NOT_FOUND;
yading@11:         goto fail;
yading@11:     }
yading@11: 
yading@11:     hls->basename = av_malloc(basename_size);
yading@11: 
yading@11:     if (!hls->basename) {
yading@11:         ret = AVERROR(ENOMEM);
yading@11:         goto fail;
yading@11:     }
yading@11: 
yading@11:     strcpy(hls->basename, s->filename);
yading@11: 
yading@11:     p = strrchr(hls->basename, '.');
yading@11: 
yading@11:     if (p)
yading@11:         *p = '\0';
yading@11: 
yading@11:     av_strlcat(hls->basename, pattern, basename_size);
yading@11: 
yading@11:     if ((ret = hls_mux_init(s)) < 0)
yading@11:         goto fail;
yading@11: 
yading@11:     if ((ret = hls_start(s)) < 0)
yading@11:         goto fail;
yading@11: 
yading@11:     if ((ret = avformat_write_header(hls->avf, NULL)) < 0)
yading@11:         return ret;
yading@11: 
yading@11: 
yading@11: fail:
yading@11:     if (ret) {
yading@11:         av_free(hls->basename);
yading@11:         if (hls->avf)
yading@11:             avformat_free_context(hls->avf);
yading@11:     }
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
yading@11: {
yading@11:     HLSContext *hls = s->priv_data;
yading@11:     AVFormatContext *oc = hls->avf;
yading@11:     AVStream *st = s->streams[pkt->stream_index];
yading@11:     int64_t end_pts = hls->recording_time * hls->number;
yading@11:     int ret, is_ref_pkt = 0;
yading@11: 
yading@11:     if (hls->start_pts == AV_NOPTS_VALUE) {
yading@11:         hls->start_pts = pkt->pts;
yading@11:         hls->end_pts   = pkt->pts;
yading@11:     }
yading@11: 
yading@11:     if ((hls->has_video && st->codec->codec_type == AVMEDIA_TYPE_VIDEO)      &&
yading@11:         pkt->pts != AV_NOPTS_VALUE) {
yading@11:         is_ref_pkt = 1;
yading@11:         hls->duration = av_rescale(pkt->pts - hls->end_pts,
yading@11:                                    st->time_base.num, st->time_base.den);
yading@11:     }
yading@11: 
yading@11:     if (is_ref_pkt &&
yading@11:         av_compare_ts(pkt->pts - hls->start_pts, st->time_base,
yading@11:                       end_pts, AV_TIME_BASE_Q) >= 0 &&
yading@11:         pkt->flags & AV_PKT_FLAG_KEY) {
yading@11: 
yading@11:         ret = append_entry(hls, hls->duration);
yading@11:         if (ret)
yading@11:             return ret;
yading@11: 
yading@11:         hls->end_pts = pkt->pts;
yading@11:         hls->duration = 0;
yading@11: 
yading@11:         av_write_frame(oc, NULL); /* Flush any buffered data */
yading@11:         avio_close(oc->pb);
yading@11: 
yading@11:         ret = hls_start(s);
yading@11: 
yading@11:         if (ret)
yading@11:             return ret;
yading@11: 
yading@11:         oc = hls->avf;
yading@11: 
yading@11:         if ((ret = hls_window(s, 0)) < 0)
yading@11:             return ret;
yading@11:     }
yading@11: 
yading@11:     ret = ff_write_chained(oc, pkt->stream_index, pkt, s);
yading@11: 
yading@11:     return ret;
yading@11: }
yading@11: 
yading@11: static int hls_write_trailer(struct AVFormatContext *s)
yading@11: {
yading@11:     HLSContext *hls = s->priv_data;
yading@11:     AVFormatContext *oc = hls->avf;
yading@11: 
yading@11:     av_write_trailer(oc);
yading@11:     avio_closep(&oc->pb);
yading@11:     avformat_free_context(oc);
yading@11:     av_free(hls->basename);
yading@11:     append_entry(hls, hls->duration);
yading@11:     hls_window(s, 1);
yading@11: 
yading@11:     free_entries(hls);
yading@11:     avio_close(hls->pb);
yading@11:     return 0;
yading@11: }
yading@11: 
yading@11: #define OFFSET(x) offsetof(HLSContext, x)
yading@11: #define E AV_OPT_FLAG_ENCODING_PARAM
yading@11: static const AVOption options[] = {
yading@11:     {"start_number",  "set first number in the sequence",        OFFSET(sequence),AV_OPT_TYPE_INT64,  {.i64 = 0},     0, INT64_MAX, E},
yading@11:     {"hls_time",      "set segment length in seconds",           OFFSET(time),    AV_OPT_TYPE_FLOAT,  {.dbl = 2},     0, FLT_MAX, E},
yading@11:     {"hls_list_size", "set maximum number of playlist entries",  OFFSET(size),    AV_OPT_TYPE_INT,    {.i64 = 5},     0, INT_MAX, E},
yading@11:     {"hls_wrap",      "set number after which the index wraps",  OFFSET(wrap),    AV_OPT_TYPE_INT,    {.i64 = 0},     0, INT_MAX, E},
yading@11:     { NULL },
yading@11: };
yading@11: 
yading@11: static const AVClass hls_class = {
yading@11:     .class_name = "hls muxer",
yading@11:     .item_name  = av_default_item_name,
yading@11:     .option     = options,
yading@11:     .version    = LIBAVUTIL_VERSION_INT,
yading@11: };
yading@11: 
yading@11: 
yading@11: AVOutputFormat ff_hls_muxer = {
yading@11:     .name           = "hls",
yading@11:     .long_name      = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),
yading@11:     .extensions     = "m3u8",
yading@11:     .priv_data_size = sizeof(HLSContext),
yading@11:     .audio_codec    = AV_CODEC_ID_MP2,
yading@11:     .video_codec    = AV_CODEC_ID_MPEG2VIDEO,
yading@11:     .flags          = AVFMT_NOFILE | AVFMT_ALLOW_FLUSH,
yading@11:     .write_header   = hls_write_header,
yading@11:     .write_packet   = hls_write_packet,
yading@11:     .write_trailer  = hls_write_trailer,
yading@11:     .priv_class     = &hls_class,
yading@11: };