hlsenc.c 9.84 KB
Newer Older
1 2 3 4
/*
 * Apple HTTP Live Streaming segmenter
 * Copyright (c) 2012, Luca Barbato
 *
5
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8 9 10 11
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
12
 * FFmpeg is distributed in the hope that it will be useful,
13 14 15 16 17
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
18
 * License along with FFmpeg; if not, write to the Free Software
19 20 21 22
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <float.h>
23
#include <stdint.h>
24 25 26 27 28 29 30 31 32 33 34 35

#include "libavutil/mathematics.h"
#include "libavutil/parseutils.h"
#include "libavutil/avstring.h"
#include "libavutil/opt.h"
#include "libavutil/log.h"

#include "avformat.h"
#include "internal.h"

typedef struct ListEntry {
    char  name[1024];
36
    double   duration;
37 38 39 40 41
    struct ListEntry *next;
} ListEntry;

typedef struct HLSContext {
    const AVClass *class;  // Class for private options.
42
    unsigned number;
43
    int64_t sequence;
44
    int64_t start_sequence;
45 46 47 48 49 50 51 52 53
    AVOutputFormat *oformat;
    AVFormatContext *avf;
    float time;            // Set by a private option.
    int  size;             // Set by a private option.
    int  wrap;             // Set by a private option.
    int64_t recording_time;
    int has_video;
    int64_t start_pts;
    int64_t end_pts;
54
    double duration;      // last segment duration computed so far, in seconds
55
    int nb_entries;
56 57 58
    ListEntry *list;
    ListEntry *end_list;
    char *basename;
59
    char *baseurl;
60 61 62 63 64 65 66 67 68 69 70 71 72 73 74
    AVIOContext *pb;
} HLSContext;

static int hls_mux_init(AVFormatContext *s)
{
    HLSContext *hls = s->priv_data;
    AVFormatContext *oc;
    int i;

    hls->avf = oc = avformat_alloc_context();
    if (!oc)
        return AVERROR(ENOMEM);

    oc->oformat            = hls->oformat;
    oc->interrupt_callback = s->interrupt_callback;
75
    av_dict_copy(&oc->metadata, s->metadata, 0);
76 77 78 79 80 81 82 83 84 85 86 87

    for (i = 0; i < s->nb_streams; i++) {
        AVStream *st;
        if (!(st = avformat_new_stream(oc, NULL)))
            return AVERROR(ENOMEM);
        avcodec_copy_context(st->codec, s->streams[i]->codec);
        st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;
    }

    return 0;
}

88
static int append_entry(HLSContext *hls, double duration)
89 90 91 92 93 94
{
    ListEntry *en = av_malloc(sizeof(*en));

    if (!en)
        return AVERROR(ENOMEM);

95
    av_strlcpy(en->name, av_basename(hls->avf->filename), sizeof(en->name));
96 97 98 99 100 101 102 103 104 105 106

    en->duration = duration;
    en->next     = NULL;

    if (!hls->list)
        hls->list = en;
    else
        hls->end_list->next = en;

    hls->end_list = en;

107
    if (hls->size && hls->nb_entries >= hls->size) {
108 109 110
        en = hls->list;
        hls->list = en->next;
        av_free(en);
111 112
    } else
        hls->nb_entries++;
113

114 115
    hls->sequence++;

116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133
    return 0;
}

static void free_entries(HLSContext *hls)
{
    ListEntry *p = hls->list, *en;

    while(p) {
        en = p;
        p = p->next;
        av_free(en);
    }
}

static int hls_window(AVFormatContext *s, int last)
{
    HLSContext *hls = s->priv_data;
    ListEntry *en;
134
    int target_duration = 0;
135
    int ret = 0;
136
    int64_t sequence = FFMAX(hls->start_sequence, hls->sequence - hls->nb_entries);
137 138 139 140 141

    if ((ret = avio_open2(&hls->pb, s->filename, AVIO_FLAG_WRITE,
                          &s->interrupt_callback, NULL)) < 0)
        goto fail;

142 143
    for (en = hls->list; en; en = en->next) {
        if (target_duration < en->duration)
144
            target_duration = (int) floor(en->duration + 0.5);
145 146
    }

147 148
    avio_printf(hls->pb, "#EXTM3U\n");
    avio_printf(hls->pb, "#EXT-X-VERSION:3\n");
149
    avio_printf(hls->pb, "#EXT-X-TARGETDURATION:%d\n", target_duration);
150
    avio_printf(hls->pb, "#EXT-X-MEDIA-SEQUENCE:%"PRId64"\n", sequence);
151

152
    av_log(s, AV_LOG_VERBOSE, "EXT-X-MEDIA-SEQUENCE:%"PRId64"\n",
153
           sequence);
154

155
    for (en = hls->list; en; en = en->next) {
156
        avio_printf(hls->pb, "#EXTINF:%f,\n", en->duration);
157 158
        if (hls->baseurl)
            avio_printf(hls->pb, "%s", hls->baseurl);
159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176
        avio_printf(hls->pb, "%s\n", en->name);
    }

    if (last)
        avio_printf(hls->pb, "#EXT-X-ENDLIST\n");

fail:
    avio_closep(&hls->pb);
    return ret;
}

static int hls_start(AVFormatContext *s)
{
    HLSContext *c = s->priv_data;
    AVFormatContext *oc = c->avf;
    int err = 0;

    if (av_get_frame_filename(oc->filename, sizeof(oc->filename),
177
                              c->basename, c->wrap ? c->sequence % c->wrap : c->sequence) < 0) {
178
        av_log(oc, AV_LOG_ERROR, "Invalid segment filename template '%s'\n", c->basename);
179
        return AVERROR(EINVAL);
180
    }
181
    c->number++;
182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198

    if ((err = avio_open2(&oc->pb, oc->filename, AVIO_FLAG_WRITE,
                          &s->interrupt_callback, NULL)) < 0)
        return err;

    if (oc->oformat->priv_class && oc->priv_data)
        av_opt_set(oc->priv_data, "mpegts_flags", "resend_headers", 0);

    return 0;
}

static int hls_write_header(AVFormatContext *s)
{
    HLSContext *hls = s->priv_data;
    int ret, i;
    char *p;
    const char *pattern = "%d.ts";
199
    int basename_size = strlen(s->filename) + strlen(pattern) + 1;
200

201
    hls->sequence       = hls->start_sequence;
202
    hls->recording_time = hls->time * AV_TIME_BASE;
203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234
    hls->start_pts      = AV_NOPTS_VALUE;

    for (i = 0; i < s->nb_streams; i++)
        hls->has_video +=
            s->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO;

    if (hls->has_video > 1)
        av_log(s, AV_LOG_WARNING,
               "More than a single video stream present, "
               "expect issues decoding it.\n");

    hls->oformat = av_guess_format("mpegts", NULL, NULL);

    if (!hls->oformat) {
        ret = AVERROR_MUXER_NOT_FOUND;
        goto fail;
    }

    hls->basename = av_malloc(basename_size);

    if (!hls->basename) {
        ret = AVERROR(ENOMEM);
        goto fail;
    }

    strcpy(hls->basename, s->filename);

    p = strrchr(hls->basename, '.');

    if (p)
        *p = '\0';

235
    av_strlcat(hls->basename, pattern, basename_size);
236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261

    if ((ret = hls_mux_init(s)) < 0)
        goto fail;

    if ((ret = hls_start(s)) < 0)
        goto fail;

    if ((ret = avformat_write_header(hls->avf, NULL)) < 0)
        return ret;


fail:
    if (ret) {
        av_free(hls->basename);
        if (hls->avf)
            avformat_free_context(hls->avf);
    }
    return ret;
}

static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)
{
    HLSContext *hls = s->priv_data;
    AVFormatContext *oc = hls->avf;
    AVStream *st = s->streams[pkt->stream_index];
    int64_t end_pts = hls->recording_time * hls->number;
262
    int is_ref_pkt = 1;
263
    int ret, can_split = 1;
264 265 266 267 268 269

    if (hls->start_pts == AV_NOPTS_VALUE) {
        hls->start_pts = pkt->pts;
        hls->end_pts   = pkt->pts;
    }

270 271 272
    if (hls->has_video) {
        can_split = st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&
                    pkt->flags & AV_PKT_FLAG_KEY;
273
        is_ref_pkt = st->codec->codec_type == AVMEDIA_TYPE_VIDEO;
274
    }
275 276
    if (pkt->pts == AV_NOPTS_VALUE)
        is_ref_pkt = can_split = 0;
277

278
    if (is_ref_pkt)
279 280
        hls->duration = (double)(pkt->pts - hls->end_pts)
                                   * st->time_base.num / st->time_base.den;
281

282 283
    if (can_split && av_compare_ts(pkt->pts - hls->start_pts, st->time_base,
                                   end_pts, AV_TIME_BASE_Q) >= 0) {
284
        ret = append_entry(hls, hls->duration);
285 286 287
        if (ret)
            return ret;

288
        hls->end_pts = pkt->pts;
289
        hls->duration = 0;
290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318

        av_write_frame(oc, NULL); /* Flush any buffered data */
        avio_close(oc->pb);

        ret = hls_start(s);

        if (ret)
            return ret;

        oc = hls->avf;

        if ((ret = hls_window(s, 0)) < 0)
            return ret;
    }

    ret = ff_write_chained(oc, pkt->stream_index, pkt, s);

    return ret;
}

static int hls_write_trailer(struct AVFormatContext *s)
{
    HLSContext *hls = s->priv_data;
    AVFormatContext *oc = hls->avf;

    av_write_trailer(oc);
    avio_closep(&oc->pb);
    avformat_free_context(oc);
    av_free(hls->basename);
319
    append_entry(hls, hls->duration);
320 321 322 323 324 325 326 327 328 329
    hls_window(s, 1);

    free_entries(hls);
    avio_close(hls->pb);
    return 0;
}

#define OFFSET(x) offsetof(HLSContext, x)
#define E AV_OPT_FLAG_ENCODING_PARAM
static const AVOption options[] = {
330
    {"start_number",  "set first number in the sequence",        OFFSET(start_sequence),AV_OPT_TYPE_INT64,  {.i64 = 0},     0, INT64_MAX, E},
331 332 333
    {"hls_time",      "set segment length in seconds",           OFFSET(time),    AV_OPT_TYPE_FLOAT,  {.dbl = 2},     0, FLT_MAX, E},
    {"hls_list_size", "set maximum number of playlist entries",  OFFSET(size),    AV_OPT_TYPE_INT,    {.i64 = 5},     0, INT_MAX, E},
    {"hls_wrap",      "set number after which the index wraps",  OFFSET(wrap),    AV_OPT_TYPE_INT,    {.i64 = 0},     0, INT_MAX, E},
334
    {"hls_base_url",  "url to prepend to each playlist entry",   OFFSET(baseurl), AV_OPT_TYPE_STRING, {.str = NULL},  0, 0,       E},
335 336 337 338 339 340 341 342 343 344 345 346 347
    { NULL },
};

static const AVClass hls_class = {
    .class_name = "hls muxer",
    .item_name  = av_default_item_name,
    .option     = options,
    .version    = LIBAVUTIL_VERSION_INT,
};


AVOutputFormat ff_hls_muxer = {
    .name           = "hls",
348
    .long_name      = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),
349 350 351 352 353 354 355 356 357 358
    .extensions     = "m3u8",
    .priv_data_size = sizeof(HLSContext),
    .audio_codec    = AV_CODEC_ID_MP2,
    .video_codec    = AV_CODEC_ID_MPEG2VIDEO,
    .flags          = AVFMT_NOFILE | AVFMT_ALLOW_FLUSH,
    .write_header   = hls_write_header,
    .write_packet   = hls_write_packet,
    .write_trailer  = hls_write_trailer,
    .priv_class     = &hls_class,
};