FFmpeg: libavformat/hlsenc.c Source File

FFmpeg

[フレーム]

libavformat

hlsenc.c

Go to the documentation of this file.

1 /*

2 * Apple HTTP Live Streaming segmenter

4 *

5 * This file is part of FFmpeg.

6 *

7 * FFmpeg is free software; you can redistribute it and/or

8 * modify it under the terms of the GNU Lesser General Public

9 * License as published by the Free Software Foundation; either

10 * version 2.1 of the License, or (at your option) any later version.

11 *

12 * FFmpeg is distributed in the hope that it will be useful,

13 * but WITHOUT ANY WARRANTY; without even the implied warranty of

14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU

15 * Lesser General Public License for more details.

16 *

17 * 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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

20 */

22 #include <float.h>

24 #include "libavutil/mathematics.h"

25 #include "libavutil/parseutils.h"

26 #include "libavutil/avstring.h"

27 #include "libavutil/opt.h"

28 #include "libavutil/log.h"

30 #include "avformat.h"

31 #include "internal.h"

33 typedef struct ListEntry {

34 char name[1024];

35 int duration;

36 struct ListEntry *next;

37 } ListEntry;

39 typedef struct HLSContext {

40 const AVClass *class; // Class for private options.

41 unsigned number;

42 int64_t sequence;

43 AVOutputFormat *oformat;

44 AVFormatContext *avf;

45 float time; // Set by a private option.

46 int size; // Set by a private option.

47 int wrap; // Set by a private option.

48 int64_t recording_time;

49 int has_video;

50 int64_t start_pts;

51 int64_t end_pts;

52 int64_t duration; // last segment duration computed so far, in seconds

53 int nb_entries;

54 ListEntry *list;

55 ListEntry *end_list;

56 char *basename;

57 AVIOContext *pb;

58 } HLSContext;

60 static int hls_mux_init(AVFormatContext *s)

61 {

62 HLSContext *hls = s->priv_data;

63 AVFormatContext *oc;

64 int i;

66 hls->avf = oc = avformat_alloc_context();

67 if (!oc)

68 return AVERROR(ENOMEM);

70 oc->oformat = hls->oformat;

71 oc->interrupt_callback = s->interrupt_callback;

73 for (i = 0; i < s->nb_streams; i++) {

74 AVStream *st;

75 if (!(st = avformat_new_stream(oc, NULL)))

76 return AVERROR(ENOMEM);

77 avcodec_copy_context(st->codec, s->streams[i]->codec);

78 st->sample_aspect_ratio = s->streams[i]->sample_aspect_ratio;

79 }

81 return 0;

82 }

84 static int append_entry(HLSContext *hls, uint64_t duration)

85 {

86 ListEntry *en = av_malloc(sizeof(*en));

88 if (!en)

89 return AVERROR(ENOMEM);

91 av_strlcpy(en->name, av_basename(hls->avf->filename), sizeof(en->name));

93 en->duration = duration;

94 en->next = NULL;

96 if (!hls->list)

97 hls->list = en;

98 else

99 hls->end_list->next = en;

100

101 hls->end_list = en;

102

103 if (hls->nb_entries >= hls->size) {

104 en = hls->list;

105 hls->list = en->next;

106 av_free(en);

107 } else

108 hls->nb_entries++;

109

110 hls->sequence++;

111

112 return 0;

113 }

114

115 static void free_entries(HLSContext *hls)

116 {

117 ListEntry *p = hls->list, *en;

118

119 while(p) {

120 en = p;

121 p = p->next;

122 av_free(en);

123 }

124 }

125

126 static int hls_window(AVFormatContext *s, int last)

127 {

128 HLSContext *hls = s->priv_data;

129 ListEntry *en;

130 int target_duration = 0;

131 int ret = 0;

132

133 if ((ret = avio_open2(&hls->pb, s->filename, AVIO_FLAG_WRITE,

134 &s->interrupt_callback, NULL)) < 0)

135 goto fail;

136

137 for (en = hls->list; en; en = en->next) {

138 if (target_duration < en->duration)

139 target_duration = en->duration;

140 }

141

142 avio_printf(hls->pb, "#EXTM3U\n");

143 avio_printf(hls->pb, "#EXT-X-VERSION:3\n");

144 avio_printf(hls->pb, "#EXT-X-TARGETDURATION:%d\n", target_duration);

145 avio_printf(hls->pb, "#EXT-X-MEDIA-SEQUENCE:%"PRId64"\n",

146 FFMAX(0, hls->sequence - hls->size));

147

148 for (en = hls->list; en; en = en->next) {

149 avio_printf(hls->pb, "#EXTINF:%d,\n", en->duration);

150 avio_printf(hls->pb, "%s\n", en->name);

151 }

152

153 if (last)

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

155

156 fail:

157 avio_closep(&hls->pb);

158 return ret;

159 }

160

161 static int hls_start(AVFormatContext *s)

162 {

163 HLSContext *c = s->priv_data;

164 AVFormatContext *oc = c->avf;

165 int err = 0;

166

167 if (av_get_frame_filename(oc->filename, sizeof(oc->filename),

168 c->basename, c->wrap ? c->number % c->wrap : c->number) < 0) {

169 av_log(oc, AV_LOG_ERROR, "Invalid segment filename template '%s'\n", c->basename);

170 return AVERROR(EINVAL);

171 }

172 c->number++;

173

174 if ((err = avio_open2(&oc->pb, oc->filename, AVIO_FLAG_WRITE,

175 &s->interrupt_callback, NULL)) < 0)

176 return err;

177

178 if (oc->oformat->priv_class && oc->priv_data)

179 av_opt_set(oc->priv_data, "mpegts_flags", "resend_headers", 0);

180

181 return 0;

182 }

183

184 static int hls_write_header(AVFormatContext *s)

185 {

186 HLSContext *hls = s->priv_data;

187 int ret, i;

188 char *p;

189 const char *pattern = "%d.ts";

190 int basename_size = strlen(s->filename) + strlen(pattern) + 1;

191

192 hls->number = 0;

193

194 hls->recording_time = hls->time * AV_TIME_BASE;

195 hls->start_pts = AV_NOPTS_VALUE;

196

197 for (i = 0; i < s->nb_streams; i++)

198 hls->has_video +=

199 s->streams[i]->codec->codec_type == AVMEDIA_TYPE_VIDEO;

200

201 if (hls->has_video > 1)

202 av_log(s, AV_LOG_WARNING,

203 "More than a single video stream present, "

204 "expect issues decoding it.\n");

205

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

207

208 if (!hls->oformat) {

209 ret = AVERROR_MUXER_NOT_FOUND;

210 goto fail;

211 }

212

213 hls->basename = av_malloc(basename_size);

214

215 if (!hls->basename) {

216 ret = AVERROR(ENOMEM);

217 goto fail;

218 }

219

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

221

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

223

224 if (p)

225 *p = '0円';

226

227 av_strlcat(hls->basename, pattern, basename_size);

228

229 if ((ret = hls_mux_init(s)) < 0)

230 goto fail;

231

232 if ((ret = hls_start(s)) < 0)

233 goto fail;

234

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

236 return ret;

237

238

239 fail:

240 if (ret) {

241 av_free(hls->basename);

242 if (hls->avf)

243 avformat_free_context(hls->avf);

244 }

245 return ret;

246 }

247

248 static int hls_write_packet(AVFormatContext *s, AVPacket *pkt)

249 {

250 HLSContext *hls = s->priv_data;

251 AVFormatContext *oc = hls->avf;

252 AVStream *st = s->streams[pkt->stream_index];

253 int64_t end_pts = hls->recording_time * hls->number;

254 int is_ref_pkt = 1;

255 int ret, can_split = 1;

256

257 if (hls->start_pts == AV_NOPTS_VALUE) {

258 hls->start_pts = pkt->pts;

259 hls->end_pts = pkt->pts;

260 }

261

262 if (hls->has_video) {

263 can_split = st->codec->codec_type == AVMEDIA_TYPE_VIDEO &&

264 pkt->flags & AV_PKT_FLAG_KEY;

265 is_ref_pkt = st->codec->codec_type == AVMEDIA_TYPE_VIDEO;

266 }

267 if (pkt->pts == AV_NOPTS_VALUE)

268 is_ref_pkt = can_split = 0;

269

270 if (is_ref_pkt)

271 hls->duration = av_rescale(pkt->pts - hls->end_pts,

272 st->time_base.num, st->time_base.den);

273

274 if (can_split && av_compare_ts(pkt->pts - hls->start_pts, st->time_base,

275 end_pts, AV_TIME_BASE_Q) >= 0) {

276 ret = append_entry(hls, hls->duration);

277 if (ret)

278 return ret;

279

280 hls->end_pts = pkt->pts;

281 hls->duration = 0;

282

283 av_write_frame(oc, NULL); /* Flush any buffered data */

284 avio_close(oc->pb);

285

286 ret = hls_start(s);

287

288 if (ret)

289 return ret;

290

291 oc = hls->avf;

292

293 if ((ret = hls_window(s, 0)) < 0)

294 return ret;

295 }

296

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

298

299 return ret;

300 }

301

302 static int hls_write_trailer(struct AVFormatContext *s)

303 {

304 HLSContext *hls = s->priv_data;

305 AVFormatContext *oc = hls->avf;

306

307 av_write_trailer(oc);

308 avio_closep(&oc->pb);

309 avformat_free_context(oc);

310 av_free(hls->basename);

311 append_entry(hls, hls->duration);

312 hls_window(s, 1);

313

314 free_entries(hls);

315 avio_close(hls->pb);

316 return 0;

317 }

318

319 #define OFFSET(x) offsetof(HLSContext, x)

320 #define E AV_OPT_FLAG_ENCODING_PARAM

321 static const AVOption options[] = {

322 {"start_number", "set first number in the sequence", OFFSET(sequence),AV_OPT_TYPE_INT64, {.i64 = 0}, 0, INT64_MAX, E},

323 {"hls_time", "set segment length in seconds", OFFSET(time), AV_OPT_TYPE_FLOAT, {.dbl = 2}, 0, FLT_MAX, E},

324 {"hls_list_size", "set maximum number of playlist entries", OFFSET(size), AV_OPT_TYPE_INT, {.i64 = 5}, 0, INT_MAX, E},

325 {"hls_wrap", "set number after which the index wraps", OFFSET(wrap), AV_OPT_TYPE_INT, {.i64 = 0}, 0, INT_MAX, E},

326 { NULL },

327 };

328

329 static const AVClass hls_class = {

330 .class_name = "hls muxer",

331 .item_name = av_default_item_name,

332 .option = options,

333 .version = LIBAVUTIL_VERSION_INT,

334 };

335

336

337 AVOutputFormat ff_hls_muxer = {

338 .name = "hls",

339 .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),

340 .extensions = "m3u8",

341 .priv_data_size = sizeof(HLSContext),

342 .audio_codec = AV_CODEC_ID_MP2,

343 .video_codec = AV_CODEC_ID_MPEG2VIDEO,

344 .flags = AVFMT_NOFILE | AVFMT_ALLOW_FLUSH,

345 .write_header = hls_write_header,

346 .write_packet = hls_write_packet,

347 .write_trailer = hls_write_trailer,

348 .priv_class = &hls_class,

349 };

Generated on Sat Jan 25 2014 19:52:02 for FFmpeg by doxygen 1.8.2