FFmpeg: libavformat/hls.c Source File

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libavformat

hls.c

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1 /*

2 * Apple HTTP Live Streaming demuxer

5 *

6 * This file is part of FFmpeg.

7 *

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

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

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

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

12 *

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

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

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

16 * Lesser General Public License for more details.

17 *

18 * You should have received a copy of the GNU Lesser General Public

19 * License along with FFmpeg; if not, write to the Free Software

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

21 */

23 /**

24 * @file

25 * Apple HTTP Live Streaming demuxer

26 * http://tools.ietf.org/html/draft-pantos-http-live-streaming

27 */

29 #include "libavutil/avstring.h"

30 #include "libavutil/avassert.h"

31 #include "libavutil/intreadwrite.h"

32 #include "libavutil/mathematics.h"

33 #include "libavutil/opt.h"

34 #include "libavutil/dict.h"

35 #include "libavutil/time.h"

36 #include "avformat.h"

37 #include "internal.h"

38 #include "avio_internal.h"

39 #include "url.h"

40 #include "id3v2.h"

42 #define INITIAL_BUFFER_SIZE 32768

44 #define MAX_FIELD_LEN 64

45 #define MAX_CHARACTERISTICS_LEN 512

47 #define MPEG_TIME_BASE 90000

48 #define MPEG_TIME_BASE_Q (AVRational){1, MPEG_TIME_BASE}

50 /*

51 * An apple http stream consists of a playlist with media segment files,

52 * played sequentially. There may be several playlists with the same

53 * video content, in different bandwidth variants, that are played in

54 * parallel (preferably only one bandwidth variant at a time). In this case,

55 * the user supplied the url to a main playlist that only lists the variant

56 * playlists.

57 *

58 * If the main playlist doesn't point at any variants, we still create

59 * one anonymous toplevel variant for this, to maintain the structure.

60 */

62 enum KeyType {

63 KEY_NONE,

64 KEY_AES_128,

65 KEY_SAMPLE_AES

66 };

68 struct segment {

69 int64_t duration;

70 int64_t url_offset;

71 int64_t size;

72 char *url;

73 char *key;

74 enum KeyType key_type;

75 uint8_t iv[16];

76 };

78 struct rendition;

80 enum PlaylistType {

81 PLS_TYPE_UNSPECIFIED,

82 PLS_TYPE_EVENT,

83 PLS_TYPE_VOD

84 };

86 /*

87 * Each playlist has its own demuxer. If it currently is active,

88 * it has an open AVIOContext too, and potentially an AVPacket

89 * containing the next packet from this stream.

90 */

91 struct playlist {

92 char url[MAX_URL_SIZE];

93 AVIOContext pb;

94 uint8_t* read_buffer;

95 URLContext *input;

96 AVFormatContext *parent;

97 int index;

98 AVFormatContext *ctx;

99 AVPacket pkt;

100 int stream_offset;

101

102 int finished;

103 enum PlaylistType type;

104 int64_t target_duration;

105 int start_seq_no;

106 int n_segments;

107 struct segment **segments;

108 int needed, cur_needed;

109 int cur_seq_no;

110 int64_t cur_seg_offset;

111 int64_t last_load_time;

112

113 char key_url[MAX_URL_SIZE];

114 uint8_t key[16];

115

116 /* ID3 timestamp handling (elementary audio streams have ID3 timestamps

117 * (and possibly other ID3 tags) in the beginning of each segment) */

118 int is_id3_timestamped; /* -1: not yet known */

119 int64_t id3_mpegts_timestamp; /* in mpegts tb */

120 int64_t id3_offset; /* in stream original tb */

121 uint8_t* id3_buf; /* temp buffer for id3 parsing */

122 unsigned int id3_buf_size;

123 AVDictionary *id3_initial; /* data from first id3 tag */

124 int id3_found; /* ID3 tag found at some point */

125 int id3_changed; /* ID3 tag data has changed at some point */

126 ID3v2ExtraMeta *id3_deferred_extra; /* stored here until subdemuxer is opened */

127

128 int64_t seek_timestamp;

129 int seek_flags;

130 int seek_stream_index; /* into subdemuxer stream array */

131

132 /* Renditions associated with this playlist, if any.

133 * Alternative rendition playlists have a single rendition associated

134 * with them, and variant main Media Playlists may have

135 * multiple (playlist-less) renditions associated with them. */

136 int n_renditions;

137 struct rendition **renditions;

138 };

139

140 /*

141 * Renditions are e.g. alternative subtitle or audio streams.

142 * The rendition may either be an external playlist or it may be

143 * contained in the main Media Playlist of the variant (in which case

144 * playlist is NULL).

145 */

146 struct rendition {

147 enum AVMediaType type;

148 struct playlist *playlist;

149 char group_id[MAX_FIELD_LEN];

150 char language[MAX_FIELD_LEN];

151 char name[MAX_FIELD_LEN];

152 int disposition;

153 };

154

155 struct variant {

156 int bandwidth;

157

158 /* every variant contains at least the main Media Playlist in index 0 */

159 int n_playlists;

160 struct playlist **playlists;

161

162 char audio_group[MAX_FIELD_LEN];

163 char video_group[MAX_FIELD_LEN];

164 char subtitles_group[MAX_FIELD_LEN];

165 };

166

167 typedef struct HLSContext {

168 int n_variants;

169 struct variant **variants;

170 int n_playlists;

171 struct playlist **playlists;

172 int n_renditions;

173 struct rendition **renditions;

174

175 int cur_seq_no;

176 int first_packet;

177 int64_t first_timestamp;

178 int64_t cur_timestamp;

179 AVIOInterruptCB *interrupt_callback;

180 char *user_agent; ///< holds HTTP user agent set as an AVOption to the HTTP protocol context

181 char *cookies; ///< holds HTTP cookie values set in either the initial response or as an AVOption to the HTTP protocol context

182 char *headers; ///< holds HTTP headers set as an AVOption to the HTTP protocol context

183 } HLSContext;

184

185 static int read_chomp_line(AVIOContext *s, char *buf, int maxlen)

186 {

187 int len = ff_get_line(s, buf, maxlen);

188 while (len > 0 && av_isspace(buf[len - 1]))

189 buf[--len] = '0円';

190 return len;

191 }

192

193 static void free_segment_list(struct playlist *pls)

194 {

195 int i;

196 for (i = 0; i < pls->n_segments; i++) {

197 av_freep(&pls->segments[i]->key);

198 av_freep(&pls->segments[i]->url);

199 av_freep(&pls->segments[i]);

200 }

201 av_freep(&pls->segments);

202 pls->n_segments = 0;

203 }

204

205 static void free_playlist_list(HLSContext *c)

206 {

207 int i;

208 for (i = 0; i < c->n_playlists; i++) {

209 struct playlist *pls = c->playlists[i];

210 free_segment_list(pls);

211 av_freep(&pls->renditions);

212 av_freep(&pls->id3_buf);

213 av_dict_free(&pls->id3_initial);

214 ff_id3v2_free_extra_meta(&pls->id3_deferred_extra);

215 av_free_packet(&pls->pkt);

216 av_freep(&pls->pb.buffer);

217 if (pls->input)

218 ffurl_close(pls->input);

219 if (pls->ctx) {

220 pls->ctx->pb = NULL;

221 avformat_close_input(&pls->ctx);

222 }

223 av_free(pls);

224 }

225 av_freep(&c->playlists);

226 av_freep(&c->cookies);

227 av_freep(&c->user_agent);

228 c->n_playlists = 0;

229 }

230

231 static void free_variant_list(HLSContext *c)

232 {

233 int i;

234 for (i = 0; i < c->n_variants; i++) {

235 struct variant *var = c->variants[i];

236 av_freep(&var->playlists);

237 av_free(var);

238 }

239 av_freep(&c->variants);

240 c->n_variants = 0;

241 }

242

243 static void free_rendition_list(HLSContext *c)

244 {

245 int i;

246 for (i = 0; i < c->n_renditions; i++)

247 av_freep(&c->renditions[i]);

248 av_freep(&c->renditions);

249 c->n_renditions = 0;

250 }

251

252 /*

253 * Used to reset a statically allocated AVPacket to a clean slate,

254 * containing no data.

255 */

256 static void reset_packet(AVPacket *pkt)

257 {

258 av_init_packet(pkt);

259 pkt->data = NULL;

260 }

261

262 static struct playlist *new_playlist(HLSContext *c, const char *url,

263 const char *base)

264 {

265 struct playlist *pls = av_mallocz(sizeof(struct playlist));

266 if (!pls)

267 return NULL;

268 reset_packet(&pls->pkt);

269 ff_make_absolute_url(pls->url, sizeof(pls->url), base, url);

270 pls->seek_timestamp = AV_NOPTS_VALUE;

271

272 pls->is_id3_timestamped = -1;

273 pls->id3_mpegts_timestamp = AV_NOPTS_VALUE;

274

275 dynarray_add(&c->playlists, &c->n_playlists, pls);

276 return pls;

277 }

278

279 struct variant_info {

280 char bandwidth[20];

281 /* variant group ids: */

282 char audio[MAX_FIELD_LEN];

283 char video[MAX_FIELD_LEN];

284 char subtitles[MAX_FIELD_LEN];

285 };

286

287 static struct variant *new_variant(HLSContext *c, struct variant_info *info,

288 const char *url, const char *base)

289 {

290 struct variant *var;

291 struct playlist *pls;

292

293 pls = new_playlist(c, url, base);

294 if (!pls)

295 return NULL;

296

297 var = av_mallocz(sizeof(struct variant));

298 if (!var)

299 return NULL;

300

301 if (info) {

302 var->bandwidth = atoi(info->bandwidth);

303 strcpy(var->audio_group, info->audio);

304 strcpy(var->video_group, info->video);

305 strcpy(var->subtitles_group, info->subtitles);

306 }

307

308 dynarray_add(&c->variants, &c->n_variants, var);

309 dynarray_add(&var->playlists, &var->n_playlists, pls);

310 return var;

311 }

312

313 static void handle_variant_args(struct variant_info *info, const char *key,

314 int key_len, char **dest, int *dest_len)

315 {

316 if (!strncmp(key, "BANDWIDTH=", key_len)) {

317 *dest = info->bandwidth;

318 *dest_len = sizeof(info->bandwidth);

319 } else if (!strncmp(key, "AUDIO=", key_len)) {

320 *dest = info->audio;

321 *dest_len = sizeof(info->audio);

322 } else if (!strncmp(key, "VIDEO=", key_len)) {

323 *dest = info->video;

324 *dest_len = sizeof(info->video);

325 } else if (!strncmp(key, "SUBTITLES=", key_len)) {

326 *dest = info->subtitles;

327 *dest_len = sizeof(info->subtitles);

328 }

329 }

330

331 struct key_info {

332 char uri[MAX_URL_SIZE];

333 char method[11];

334 char iv[35];

335 };

336

337 static void handle_key_args(struct key_info *info, const char *key,

338 int key_len, char **dest, int *dest_len)

339 {

340 if (!strncmp(key, "METHOD=", key_len)) {

341 *dest = info->method;

342 *dest_len = sizeof(info->method);

343 } else if (!strncmp(key, "URI=", key_len)) {

344 *dest = info->uri;

345 *dest_len = sizeof(info->uri);

346 } else if (!strncmp(key, "IV=", key_len)) {

347 *dest = info->iv;

348 *dest_len = sizeof(info->iv);

349 }

350 }

351

352 struct rendition_info {

353 char type[16];

354 char uri[MAX_URL_SIZE];

355 char group_id[MAX_FIELD_LEN];

356 char language[MAX_FIELD_LEN];

357 char assoc_language[MAX_FIELD_LEN];

358 char name[MAX_FIELD_LEN];

359 char defaultr[4];

360 char forced[4];

361 char characteristics[MAX_CHARACTERISTICS_LEN];

362 };

363

364 static struct rendition *new_rendition(HLSContext *c, struct rendition_info *info,

365 const char *url_base)

366 {

367 struct rendition *rend;

368 enum AVMediaType type = AVMEDIA_TYPE_UNKNOWN;

369 char *characteristic;

370 char *chr_ptr;

371 char *saveptr;

372

373 if (!strcmp(info->type, "AUDIO"))

374 type = AVMEDIA_TYPE_AUDIO;

375 else if (!strcmp(info->type, "VIDEO"))

376 type = AVMEDIA_TYPE_VIDEO;

377 else if (!strcmp(info->type, "SUBTITLES"))

378 type = AVMEDIA_TYPE_SUBTITLE;

379 else if (!strcmp(info->type, "CLOSED-CAPTIONS"))

380 /* CLOSED-CAPTIONS is ignored since we do not support CEA-608 CC in

381 * AVC SEI RBSP anyway */

382 return NULL;

383

384 if (type == AVMEDIA_TYPE_UNKNOWN)

385 return NULL;

386

387 /* URI is mandatory for subtitles as per spec */

388 if (type == AVMEDIA_TYPE_SUBTITLE && !info->uri[0])

389 return NULL;

390

391 /* TODO: handle subtitles (each segment has to parsed separately) */

392 if (type == AVMEDIA_TYPE_SUBTITLE)

393 return NULL;

394

395 rend = av_mallocz(sizeof(struct rendition));

396 if (!rend)

397 return NULL;

398

399 dynarray_add(&c->renditions, &c->n_renditions, rend);

400

401 rend->type = type;

402 strcpy(rend->group_id, info->group_id);

403 strcpy(rend->language, info->language);

404 strcpy(rend->name, info->name);

405

406 /* add the playlist if this is an external rendition */

407 if (info->uri[0]) {

408 rend->playlist = new_playlist(c, info->uri, url_base);

409 if (rend->playlist)

410 dynarray_add(&rend->playlist->renditions,

411 &rend->playlist->n_renditions, rend);

412 }

413

414 if (info->assoc_language[0]) {

415 int langlen = strlen(rend->language);

416 if (langlen < sizeof(rend->language) - 3) {

417 rend->language[langlen] = ',';

418 strncpy(rend->language + langlen + 1, info->assoc_language,

419 sizeof(rend->language) - langlen - 2);

420 }

421 }

422

423 if (!strcmp(info->defaultr, "YES"))

424 rend->disposition |= AV_DISPOSITION_DEFAULT;

425 if (!strcmp(info->forced, "YES"))

426 rend->disposition |= AV_DISPOSITION_FORCED;

427

428 chr_ptr = info->characteristics;

429 while ((characteristic = av_strtok(chr_ptr, ",", &saveptr))) {

430 if (!strcmp(characteristic, "public.accessibility.describes-music-and-sound"))

431 rend->disposition |= AV_DISPOSITION_HEARING_IMPAIRED;

432 else if (!strcmp(characteristic, "public.accessibility.describes-video"))

433 rend->disposition |= AV_DISPOSITION_VISUAL_IMPAIRED;

434

435 chr_ptr = NULL;

436 }

437

438 return rend;

439 }

440

441 static void handle_rendition_args(struct rendition_info *info, const char *key,

442 int key_len, char **dest, int *dest_len)

443 {

444 if (!strncmp(key, "TYPE=", key_len)) {

445 *dest = info->type;

446 *dest_len = sizeof(info->type);

447 } else if (!strncmp(key, "URI=", key_len)) {

448 *dest = info->uri;

449 *dest_len = sizeof(info->uri);

450 } else if (!strncmp(key, "GROUP-ID=", key_len)) {

451 *dest = info->group_id;

452 *dest_len = sizeof(info->group_id);

453 } else if (!strncmp(key, "LANGUAGE=", key_len)) {

454 *dest = info->language;

455 *dest_len = sizeof(info->language);

456 } else if (!strncmp(key, "ASSOC-LANGUAGE=", key_len)) {

457 *dest = info->assoc_language;

458 *dest_len = sizeof(info->assoc_language);

459 } else if (!strncmp(key, "NAME=", key_len)) {

460 *dest = info->name;

461 *dest_len = sizeof(info->name);

462 } else if (!strncmp(key, "DEFAULT=", key_len)) {

463 *dest = info->defaultr;

464 *dest_len = sizeof(info->defaultr);

465 } else if (!strncmp(key, "FORCED=", key_len)) {

466 *dest = info->forced;

467 *dest_len = sizeof(info->forced);

468 } else if (!strncmp(key, "CHARACTERISTICS=", key_len)) {

469 *dest = info->characteristics;

470 *dest_len = sizeof(info->characteristics);

471 }

472 /*

473 * ignored:

474 * - AUTOSELECT: client may autoselect based on e.g. system language

475 * - INSTREAM-ID: EIA-608 closed caption number ("CC1".."CC4")

476 */

477 }

478

479 /* used by parse_playlist to allocate a new variant+playlist when the

480 * playlist is detected to be a Media Playlist (not Master Playlist)

481 * and we have no parent Master Playlist (parsing of which would have

482 * allocated the variant and playlist already) */

483 static int ensure_playlist(HLSContext *c, struct playlist **pls, const char *url)

484 {

485 if (*pls)

486 return 0;

487 if (!new_variant(c, NULL, url, NULL))

488 return AVERROR(ENOMEM);

489 *pls = c->playlists[c->n_playlists - 1];

490 return 0;

491 }

492

493 /* pls = NULL => Master Playlist or parentless Media Playlist

494 * pls = !NULL => parented Media Playlist, playlist+variant allocated */

495 static int parse_playlist(HLSContext *c, const char *url,

496 struct playlist *pls, AVIOContext *in)

497 {

498 int ret = 0, is_segment = 0, is_variant = 0;

499 int64_t duration = 0;

500 enum KeyType key_type = KEY_NONE;

501 uint8_t iv[16] = "";

502 int has_iv = 0;

503 char key[MAX_URL_SIZE] = "";

504 char line[MAX_URL_SIZE];

505 const char *ptr;

506 int close_in = 0;

507 int64_t seg_offset = 0;

508 int64_t seg_size = -1;

509 uint8_t *new_url = NULL;

510 struct variant_info variant_info;

511 char tmp_str[MAX_URL_SIZE];

512

513 if (!in) {

514 AVDictionary *opts = NULL;

515 close_in = 1;

516 /* Some HLS servers don't like being sent the range header */

517 av_dict_set(&opts, "seekable", "0", 0);

518

519 // broker prior HTTP options that should be consistent across requests

520 av_dict_set(&opts, "user-agent", c->user_agent, 0);

521 av_dict_set(&opts, "cookies", c->cookies, 0);

522 av_dict_set(&opts, "headers", c->headers, 0);

523

524 ret = avio_open2(&in, url, AVIO_FLAG_READ,

525 c->interrupt_callback, &opts);

526 av_dict_free(&opts);

527 if (ret < 0)

528 return ret;

529 }

530

531 if (av_opt_get(in, "location", AV_OPT_SEARCH_CHILDREN, &new_url) >= 0)

532 url = new_url;

533

534 read_chomp_line(in, line, sizeof(line));

535 if (strcmp(line, "#EXTM3U")) {

536 ret = AVERROR_INVALIDDATA;

537 goto fail;

538 }

539

540 if (pls) {

541 free_segment_list(pls);

542 pls->finished = 0;

543 pls->type = PLS_TYPE_UNSPECIFIED;

544 }

545 while (!avio_feof(in)) {

546 read_chomp_line(in, line, sizeof(line));

547 if (av_strstart(line, "#EXT-X-STREAM-INF:", &ptr)) {

548 is_variant = 1;

549 memset(&variant_info, 0, sizeof(variant_info));

550 ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_variant_args,

551 &variant_info);

552 } else if (av_strstart(line, "#EXT-X-KEY:", &ptr)) {

553 struct key_info info = {{0}};

554 ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_key_args,

555 &info);

556 key_type = KEY_NONE;

557 has_iv = 0;

558 if (!strcmp(info.method, "AES-128"))

559 key_type = KEY_AES_128;

560 if (!strcmp(info.method, "SAMPLE-AES"))

561 key_type = KEY_SAMPLE_AES;

562 if (!strncmp(info.iv, "0x", 2) || !strncmp(info.iv, "0X", 2)) {

563 ff_hex_to_data(iv, info.iv + 2);

564 has_iv = 1;

565 }

566 av_strlcpy(key, info.uri, sizeof(key));

567 } else if (av_strstart(line, "#EXT-X-MEDIA:", &ptr)) {

568 struct rendition_info info = {{0}};

569 ff_parse_key_value(ptr, (ff_parse_key_val_cb) handle_rendition_args,

570 &info);

571 new_rendition(c, &info, url);

572 } else if (av_strstart(line, "#EXT-X-TARGETDURATION:", &ptr)) {

573 ret = ensure_playlist(c, &pls, url);

574 if (ret < 0)

575 goto fail;

576 pls->target_duration = atoi(ptr) * AV_TIME_BASE;

577 } else if (av_strstart(line, "#EXT-X-MEDIA-SEQUENCE:", &ptr)) {

578 ret = ensure_playlist(c, &pls, url);

579 if (ret < 0)

580 goto fail;

581 pls->start_seq_no = atoi(ptr);

582 } else if (av_strstart(line, "#EXT-X-PLAYLIST-TYPE:", &ptr)) {

583 ret = ensure_playlist(c, &pls, url);

584 if (ret < 0)

585 goto fail;

586 if (!strcmp(ptr, "EVENT"))

587 pls->type = PLS_TYPE_EVENT;

588 else if (!strcmp(ptr, "VOD"))

589 pls->type = PLS_TYPE_VOD;

590 } else if (av_strstart(line, "#EXT-X-ENDLIST", &ptr)) {

591 if (pls)

592 pls->finished = 1;

593 } else if (av_strstart(line, "#EXTINF:", &ptr)) {

594 is_segment = 1;

595 duration = atof(ptr) * AV_TIME_BASE;

596 } else if (av_strstart(line, "#EXT-X-BYTERANGE:", &ptr)) {

597 seg_size = atoi(ptr);

598 ptr = strchr(ptr, '@');

599 if (ptr)

600 seg_offset = atoi(ptr+1);

601 } else if (av_strstart(line, "#", NULL)) {

602 continue;

603 } else if (line[0]) {

604 if (is_variant) {

605 if (!new_variant(c, &variant_info, line, url)) {

606 ret = AVERROR(ENOMEM);

607 goto fail;

608 }

609 is_variant = 0;

610 }

611 if (is_segment) {

612 struct segment *seg;

613 if (!pls) {

614 if (!new_variant(c, 0, url, NULL)) {

615 ret = AVERROR(ENOMEM);

616 goto fail;

617 }

618 pls = c->playlists[c->n_playlists - 1];

619 }

620 seg = av_malloc(sizeof(struct segment));

621 if (!seg) {

622 ret = AVERROR(ENOMEM);

623 goto fail;

624 }

625 seg->duration = duration;

626 seg->key_type = key_type;

627 if (has_iv) {

628 memcpy(seg->iv, iv, sizeof(iv));

629 } else {

630 int seq = pls->start_seq_no + pls->n_segments;

631 memset(seg->iv, 0, sizeof(seg->iv));

632 AV_WB32(seg->iv + 12, seq);

633 }

634

635 if (key_type != KEY_NONE) {

636 ff_make_absolute_url(tmp_str, sizeof(tmp_str), url, key);

637 seg->key = av_strdup(tmp_str);

638 if (!seg->key) {

639 av_free(seg);

640 ret = AVERROR(ENOMEM);

641 goto fail;

642 }

643 } else {

644 seg->key = NULL;

645 }

646

647 ff_make_absolute_url(tmp_str, sizeof(tmp_str), url, line);

648 seg->url = av_strdup(tmp_str);

649 if (!seg->url) {

650 av_free(seg->key);

651 av_free(seg);

652 ret = AVERROR(ENOMEM);

653 goto fail;

654 }

655

656 dynarray_add(&pls->segments, &pls->n_segments, seg);

657 is_segment = 0;

658

659 seg->size = seg_size;

660 if (seg_size >= 0) {

661 seg->url_offset = seg_offset;

662 seg_offset += seg_size;

663 seg_size = -1;

664 } else {

665 seg->url_offset = 0;

666 seg_offset = 0;

667 }

668 }

669 }

670 }

671 if (pls)

672 pls->last_load_time = av_gettime_relative();

673

674 fail:

675 av_free(new_url);

676 if (close_in)

677 avio_close(in);

678 return ret;

679 }

680

681 enum ReadFromURLMode {

682 READ_NORMAL,

683 READ_COMPLETE,

684 };

685

686 /* read from URLContext, limiting read to current segment */

687 static int read_from_url(struct playlist *pls, uint8_t *buf, int buf_size,

688 enum ReadFromURLMode mode)

689 {

690 int ret;

691 struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no];

692

693 /* limit read if the segment was only a part of a file */

694 if (seg->size >= 0)

695 buf_size = FFMIN(buf_size, seg->size - pls->cur_seg_offset);

696

697 if (mode == READ_COMPLETE)

698 ret = ffurl_read_complete(pls->input, buf, buf_size);

699 else

700 ret = ffurl_read(pls->input, buf, buf_size);

701

702 if (ret > 0)

703 pls->cur_seg_offset += ret;

704

705 return ret;

706 }

707

708 /* Parse the raw ID3 data and pass contents to caller */

709 static void parse_id3(AVFormatContext *s, AVIOContext *pb,

710 AVDictionary **metadata, int64_t *dts,

711 ID3v2ExtraMetaAPIC **apic, ID3v2ExtraMeta **extra_meta)

712 {

713 static const char id3_priv_owner_ts[] = "com.apple.streaming.transportStreamTimestamp";

714 ID3v2ExtraMeta *meta;

715

716 ff_id3v2_read_dict(pb, metadata, ID3v2_DEFAULT_MAGIC, extra_meta);

717 for (meta = *extra_meta; meta; meta = meta->next) {

718 if (!strcmp(meta->tag, "PRIV")) {

719 ID3v2ExtraMetaPRIV *priv = meta->data;

720 if (priv->datasize == 8 && !strcmp(priv->owner, id3_priv_owner_ts)) {

721 /* 33-bit MPEG timestamp */

722 int64_t ts = AV_RB64(priv->data);

723 av_log(s, AV_LOG_DEBUG, "HLS ID3 audio timestamp %"PRId64"\n", ts);

724 if ((ts & ~((1ULL << 33) - 1)) == 0)

725 *dts = ts;

726 else

727 av_log(s, AV_LOG_ERROR, "Invalid HLS ID3 audio timestamp %"PRId64"\n", ts);

728 }

729 } else if (!strcmp(meta->tag, "APIC") && apic)

730 *apic = meta->data;

731 }

732 }

733

734 /* Check if the ID3 metadata contents have changed */

735 static int id3_has_changed_values(struct playlist *pls, AVDictionary *metadata,

736 ID3v2ExtraMetaAPIC *apic)

737 {

738 AVDictionaryEntry *entry = NULL;

739 AVDictionaryEntry *oldentry;

740 /* check that no keys have changed values */

741 while ((entry = av_dict_get(metadata, "", entry, AV_DICT_IGNORE_SUFFIX))) {

742 oldentry = av_dict_get(pls->id3_initial, entry->key, NULL, AV_DICT_MATCH_CASE);

743 if (!oldentry || strcmp(oldentry->value, entry->value) != 0)

744 return 1;

745 }

746

747 /* check if apic appeared */

748 if (apic && (pls->ctx->nb_streams != 2 || !pls->ctx->streams[1]->attached_pic.data))

749 return 1;

750

751 if (apic) {

752 int size = pls->ctx->streams[1]->attached_pic.size;

753 if (size != apic->buf->size - FF_INPUT_BUFFER_PADDING_SIZE)

754 return 1;

755

756 if (memcmp(apic->buf->data, pls->ctx->streams[1]->attached_pic.data, size) != 0)

757 return 1;

758 }

759

760 return 0;

761 }

762

763 /* Parse ID3 data and handle the found data */

764 static void handle_id3(AVIOContext *pb, struct playlist *pls)

765 {

766 AVDictionary *metadata = NULL;

767 ID3v2ExtraMetaAPIC *apic = NULL;

768 ID3v2ExtraMeta *extra_meta = NULL;

769 int64_t timestamp = AV_NOPTS_VALUE;

770

771 parse_id3(pls->ctx, pb, &metadata, &timestamp, &apic, &extra_meta);

772

773 if (timestamp != AV_NOPTS_VALUE) {

774 pls->id3_mpegts_timestamp = timestamp;

775 pls->id3_offset = 0;

776 }

777

778 if (!pls->id3_found) {

779 /* initial ID3 tags */

780 av_assert0(!pls->id3_deferred_extra);

781 pls->id3_found = 1;

782

783 /* get picture attachment and set text metadata */

784 if (pls->ctx->nb_streams)

785 ff_id3v2_parse_apic(pls->ctx, &extra_meta);

786 else

787 /* demuxer not yet opened, defer picture attachment */

788 pls->id3_deferred_extra = extra_meta;

789

790 av_dict_copy(&pls->ctx->metadata, metadata, 0);

791 pls->id3_initial = metadata;

792

793 } else {

794 if (!pls->id3_changed && id3_has_changed_values(pls, metadata, apic)) {

795 avpriv_report_missing_feature(pls->ctx, "Changing ID3 metadata in HLS audio elementary stream");

796 pls->id3_changed = 1;

797 }

798 av_dict_free(&metadata);

799 }

800

801 if (!pls->id3_deferred_extra)

802 ff_id3v2_free_extra_meta(&extra_meta);

803 }

804

805 /* Intercept and handle ID3 tags between URLContext and AVIOContext */

806 static void intercept_id3(struct playlist *pls, uint8_t *buf,

807 int buf_size, int *len)

808 {

809 /* intercept id3 tags, we do not want to pass them to the raw

810 * demuxer on all segment switches */

811 int bytes;

812 int id3_buf_pos = 0;

813 int fill_buf = 0;

814

815 /* gather all the id3 tags */

816 while (1) {

817 /* see if we can retrieve enough data for ID3 header */

818 if (*len < ID3v2_HEADER_SIZE && buf_size >= ID3v2_HEADER_SIZE) {

819 bytes = read_from_url(pls, buf + *len, ID3v2_HEADER_SIZE - *len, READ_COMPLETE);

820 if (bytes > 0) {

821

822 if (bytes == ID3v2_HEADER_SIZE - *len)

823 /* no EOF yet, so fill the caller buffer again after

824 * we have stripped the ID3 tags */

825 fill_buf = 1;

826

827 *len += bytes;

828

829 } else if (*len <= 0) {

830 /* error/EOF */

831 *len = bytes;

832 fill_buf = 0;

833 }

834 }

835

836 if (*len < ID3v2_HEADER_SIZE)

837 break;

838

839 if (ff_id3v2_match(buf, ID3v2_DEFAULT_MAGIC)) {

840 struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no];

841 int64_t maxsize = seg->size >= 0 ? seg->size : 1024*1024;

842 int taglen = ff_id3v2_tag_len(buf);

843 int tag_got_bytes = FFMIN(taglen, *len);

844 int remaining = taglen - tag_got_bytes;

845

846 if (taglen > maxsize) {

847 av_log(pls->ctx, AV_LOG_ERROR, "Too large HLS ID3 tag (%d > %"PRId64" bytes)\n",

848 taglen, maxsize);

849 break;

850 }

851

852 /*

853 * Copy the id3 tag to our temporary id3 buffer.

854 * We could read a small id3 tag directly without memcpy, but

855 * we would still need to copy the large tags, and handling

856 * both of those cases together with the possibility for multiple

857 * tags would make the handling a bit complex.

858 */

859 pls->id3_buf = av_fast_realloc(pls->id3_buf, &pls->id3_buf_size, id3_buf_pos + taglen);

860 if (!pls->id3_buf)

861 break;

862 memcpy(pls->id3_buf + id3_buf_pos, buf, tag_got_bytes);

863 id3_buf_pos += tag_got_bytes;

864

865 /* strip the intercepted bytes */

866 *len -= tag_got_bytes;

867 memmove(buf, buf + tag_got_bytes, *len);

868 av_log(pls->ctx, AV_LOG_DEBUG, "Stripped %d HLS ID3 bytes\n", tag_got_bytes);

869

870 if (remaining > 0) {

871 /* read the rest of the tag in */

872 if (read_from_url(pls, pls->id3_buf + id3_buf_pos, remaining, READ_COMPLETE) != remaining)

873 break;

874 id3_buf_pos += remaining;

875 av_log(pls->ctx, AV_LOG_DEBUG, "Stripped additional %d HLS ID3 bytes\n", remaining);

876 }

877

878 } else {

879 /* no more ID3 tags */

880 break;

881 }

882 }

883

884 /* re-fill buffer for the caller unless EOF */

885 if (*len >= 0 && (fill_buf || *len == 0)) {

886 bytes = read_from_url(pls, buf + *len, buf_size - *len, READ_NORMAL);

887

888 /* ignore error if we already had some data */

889 if (bytes >= 0)

890 *len += bytes;

891 else if (*len == 0)

892 *len = bytes;

893 }

894

895 if (pls->id3_buf) {

896 /* Now parse all the ID3 tags */

897 AVIOContext id3ioctx;

898 ffio_init_context(&id3ioctx, pls->id3_buf, id3_buf_pos, 0, NULL, NULL, NULL, NULL);

899 handle_id3(&id3ioctx, pls);

900 }

901

902 if (pls->is_id3_timestamped == -1)

903 pls->is_id3_timestamped = (pls->id3_mpegts_timestamp != AV_NOPTS_VALUE);

904 }

905

906 static int open_input(HLSContext *c, struct playlist *pls)

907 {

908 AVDictionary *opts = NULL;

909 AVDictionary *opts2 = NULL;

910 int ret;

911 struct segment *seg = pls->segments[pls->cur_seq_no - pls->start_seq_no];

912

913 // broker prior HTTP options that should be consistent across requests

914 av_dict_set(&opts, "user-agent", c->user_agent, 0);

915 av_dict_set(&opts, "cookies", c->cookies, 0);

916 av_dict_set(&opts, "headers", c->headers, 0);

917 av_dict_set(&opts, "seekable", "0", 0);

918

919 // Same opts for key request (ffurl_open mutilates the opts so it cannot be used twice)

920 av_dict_copy(&opts2, opts, 0);

921

922 if (seg->size >= 0) {

923 /* try to restrict the HTTP request to the part we want

924 * (if this is in fact a HTTP request) */

925 av_dict_set_int(&opts, "offset", seg->url_offset, 0);

926 av_dict_set_int(&opts, "end_offset", seg->url_offset + seg->size, 0);

927 }

928

929 av_log(pls->parent, AV_LOG_VERBOSE, "HLS request for url '%s', offset %"PRId64", playlist %d\n",

930 seg->url, seg->url_offset, pls->index);

931

932 if (seg->key_type == KEY_NONE) {

933 ret = ffurl_open(&pls->input, seg->url, AVIO_FLAG_READ,

934 &pls->parent->interrupt_callback, &opts);

935

936 } else if (seg->key_type == KEY_AES_128) {

937 char iv[33], key[33], url[MAX_URL_SIZE];

938 if (strcmp(seg->key, pls->key_url)) {

939 URLContext *uc;

940 if (ffurl_open(&uc, seg->key, AVIO_FLAG_READ,

941 &pls->parent->interrupt_callback, &opts2) == 0) {

942 if (ffurl_read_complete(uc, pls->key, sizeof(pls->key))

943 != sizeof(pls->key)) {

944 av_log(NULL, AV_LOG_ERROR, "Unable to read key file %s\n",

945 seg->key);

946 }

947 ffurl_close(uc);

948 } else {

949 av_log(NULL, AV_LOG_ERROR, "Unable to open key file %s\n",

950 seg->key);

951 }

952 av_strlcpy(pls->key_url, seg->key, sizeof(pls->key_url));

953 }

954 ff_data_to_hex(iv, seg->iv, sizeof(seg->iv), 0);

955 ff_data_to_hex(key, pls->key, sizeof(pls->key), 0);

956 iv[32] = key[32] = '0円';

957 if (strstr(seg->url, "://"))

958 snprintf(url, sizeof(url), "crypto+%s", seg->url);

959 else

960 snprintf(url, sizeof(url), "crypto:%s", seg->url);

961 if ((ret = ffurl_alloc(&pls->input, url, AVIO_FLAG_READ,

962 &pls->parent->interrupt_callback)) < 0)

963 goto cleanup;

964 av_opt_set(pls->input->priv_data, "key", key, 0);

965 av_opt_set(pls->input->priv_data, "iv", iv, 0);

966

967 if ((ret = ffurl_connect(pls->input, &opts)) < 0) {

968 ffurl_close(pls->input);

969 pls->input = NULL;

970 goto cleanup;

971 }

972 ret = 0;

973 } else if (seg->key_type == KEY_SAMPLE_AES) {

974 av_log(pls->parent, AV_LOG_ERROR,

975 "SAMPLE-AES encryption is not supported yet\n");

976 ret = AVERROR_PATCHWELCOME;

977 }

978 else

979 ret = AVERROR(ENOSYS);

980

981 /* Seek to the requested position. If this was a HTTP request, the offset

982 * should already be where want it to, but this allows e.g. local testing

983 * without a HTTP server. */

984 if (ret == 0 && seg->key_type == KEY_NONE) {

985 int seekret = ffurl_seek(pls->input, seg->url_offset, SEEK_SET);

986 if (seekret < 0) {

987 av_log(pls->parent, AV_LOG_ERROR, "Unable to seek to offset %"PRId64" of HLS segment '%s'\n", seg->url_offset, seg->url);

988 ret = seekret;

989 ffurl_close(pls->input);

990 pls->input = NULL;

991 }

992 }

993

994 cleanup:

995 av_dict_free(&opts);

996 av_dict_free(&opts2);

997 pls->cur_seg_offset = 0;

998 return ret;

999 }

1000

1001 static int64_t default_reload_interval(struct playlist *pls)

1002 {

1003 return pls->n_segments > 0 ?

1004 pls->segments[pls->n_segments - 1]->duration :

1005 pls->target_duration;

1006 }

1007

1008 static int read_data(void *opaque, uint8_t *buf, int buf_size)

1009 {

1010 struct playlist *v = opaque;

1011 HLSContext *c = v->parent->priv_data;

1012 int ret, i;

1013 int just_opened = 0;

1014

1015 restart:

1016 if (!v->needed)

1017 return AVERROR_EOF;

1018

1019 if (!v->input) {

1020 int64_t reload_interval;

1021

1022 /* Check that the playlist is still needed before opening a new

1023 * segment. */

1024 if (v->ctx && v->ctx->nb_streams &&

1025 v->parent->nb_streams >= v->stream_offset + v->ctx->nb_streams) {

1026 v->needed = 0;

1027 for (i = v->stream_offset; i < v->stream_offset + v->ctx->nb_streams;

1028 i++) {

1029 if (v->parent->streams[i]->discard < AVDISCARD_ALL)

1030 v->needed = 1;

1031 }

1032 }

1033 if (!v->needed) {

1034 av_log(v->parent, AV_LOG_INFO, "No longer receiving playlist %d\n",

1035 v->index);

1036 return AVERROR_EOF;

1037 }

1038

1039 /* If this is a live stream and the reload interval has elapsed since

1040 * the last playlist reload, reload the playlists now. */

1041 reload_interval = default_reload_interval(v);

1042

1043 reload:

1044 if (!v->finished &&

1045 av_gettime_relative() - v->last_load_time >= reload_interval) {

1046 if ((ret = parse_playlist(c, v->url, v, NULL)) < 0) {

1047 av_log(v->parent, AV_LOG_WARNING, "Failed to reload playlist %d\n",

1048 v->index);

1049 return ret;

1050 }

1051 /* If we need to reload the playlist again below (if

1052 * there's still no more segments), switch to a reload

1053 * interval of half the target duration. */

1054 reload_interval = v->target_duration / 2;

1055 }

1056 if (v->cur_seq_no < v->start_seq_no) {

1057 av_log(NULL, AV_LOG_WARNING,

1058 "skipping %d segments ahead, expired from playlists\n",

1059 v->start_seq_no - v->cur_seq_no);

1060 v->cur_seq_no = v->start_seq_no;

1061 }

1062 if (v->cur_seq_no >= v->start_seq_no + v->n_segments) {

1063 if (v->finished)

1064 return AVERROR_EOF;

1065 while (av_gettime_relative() - v->last_load_time < reload_interval) {

1066 if (ff_check_interrupt(c->interrupt_callback))

1067 return AVERROR_EXIT;

1068 av_usleep(100*1000);

1069 }

1070 /* Enough time has elapsed since the last reload */

1071 goto reload;

1072 }

1073

1074 ret = open_input(c, v);

1075 if (ret < 0) {

1076 av_log(v->parent, AV_LOG_WARNING, "Failed to open segment of playlist %d\n",

1077 v->index);

1078 return ret;

1079 }

1080 just_opened = 1;

1081 }

1082

1083 ret = read_from_url(v, buf, buf_size, READ_NORMAL);

1084 if (ret > 0) {

1085 if (just_opened && v->is_id3_timestamped != 0) {

1086 /* Intercept ID3 tags here, elementary audio streams are required

1087 * to convey timestamps using them in the beginning of each segment. */

1088 intercept_id3(v, buf, buf_size, &ret);

1089 }

1090

1091 return ret;

1092 }

1093 ffurl_close(v->input);

1094 v->input = NULL;

1095 v->cur_seq_no++;

1096

1097 c->cur_seq_no = v->cur_seq_no;

1098

1099 goto restart;

1100 }

1101

1102 static int playlist_in_multiple_variants(HLSContext *c, struct playlist *pls)

1103 {

1104 int variant_count = 0;

1105 int i, j;

1106

1107 for (i = 0; i < c->n_variants && variant_count < 2; i++) {

1108 struct variant *v = c->variants[i];

1109

1110 for (j = 0; j < v->n_playlists; j++) {

1111 if (v->playlists[j] == pls) {

1112 variant_count++;

1113 break;

1114 }

1115 }

1116 }

1117

1118 return variant_count >= 2;

1119 }

1120

1121 static void add_renditions_to_variant(HLSContext *c, struct variant *var,

1122 enum AVMediaType type, const char *group_id)

1123 {

1124 int i;

1125

1126 for (i = 0; i < c->n_renditions; i++) {

1127 struct rendition *rend = c->renditions[i];

1128

1129 if (rend->type == type && !strcmp(rend->group_id, group_id)) {

1130

1131 if (rend->playlist)

1132 /* rendition is an external playlist

1133 * => add the playlist to the variant */

1134 dynarray_add(&var->playlists, &var->n_playlists, rend->playlist);

1135 else

1136 /* rendition is part of the variant main Media Playlist

1137 * => add the rendition to the main Media Playlist */

1138 dynarray_add(&var->playlists[0]->renditions,

1139 &var->playlists[0]->n_renditions,

1140 rend);

1141 }

1142 }

1143 }

1144

1145 static void add_metadata_from_renditions(AVFormatContext *s, struct playlist *pls,

1146 enum AVMediaType type)

1147 {

1148 int rend_idx = 0;

1149 int i;

1150

1151 for (i = 0; i < pls->ctx->nb_streams; i++) {

1152 AVStream *st = s->streams[pls->stream_offset + i];

1153

1154 if (st->codec->codec_type != type)

1155 continue;

1156

1157 for (; rend_idx < pls->n_renditions; rend_idx++) {

1158 struct rendition *rend = pls->renditions[rend_idx];

1159

1160 if (rend->type != type)

1161 continue;

1162

1163 if (rend->language[0])

1164 av_dict_set(&st->metadata, "language", rend->language, 0);

1165 if (rend->name[0])

1166 av_dict_set(&st->metadata, "comment", rend->name, 0);

1167

1168 st->disposition |= rend->disposition;

1169 }

1170 if (rend_idx >=pls->n_renditions)

1171 break;

1172 }

1173 }

1174

1175 /* if timestamp was in valid range: returns 1 and sets seq_no

1176 * if not: returns 0 and sets seq_no to closest segment */

1177 static int find_timestamp_in_playlist(HLSContext *c, struct playlist *pls,

1178 int64_t timestamp, int *seq_no)

1179 {

1180 int i;

1181 int64_t pos = c->first_timestamp == AV_NOPTS_VALUE ?

1182 0 : c->first_timestamp;

1183

1184 if (timestamp < pos) {

1185 *seq_no = pls->start_seq_no;

1186 return 0;

1187 }

1188

1189 for (i = 0; i < pls->n_segments; i++) {

1190 int64_t diff = pos + pls->segments[i]->duration - timestamp;

1191 if (diff > 0) {

1192 *seq_no = pls->start_seq_no + i;

1193 return 1;

1194 }

1195 pos += pls->segments[i]->duration;

1196 }

1197

1198 *seq_no = pls->start_seq_no + pls->n_segments - 1;

1199

1200 return 0;

1201 }

1202

1203 static int select_cur_seq_no(HLSContext *c, struct playlist *pls)

1204 {

1205 int seq_no;

1206

1207 if (!pls->finished && !c->first_packet &&

1208 av_gettime_relative() - pls->last_load_time >= default_reload_interval(pls))

1209 /* reload the playlist since it was suspended */

1210 parse_playlist(c, pls->url, pls, NULL);

1211

1212 /* If playback is already in progress (we are just selecting a new

1213 * playlist) and this is a complete file, find the matching segment

1214 * by counting durations. */

1215 if (pls->finished && c->cur_timestamp != AV_NOPTS_VALUE) {

1216 find_timestamp_in_playlist(c, pls, c->cur_timestamp, &seq_no);

1217 return seq_no;

1218 }

1219

1220 if (!pls->finished) {

1221 if (!c->first_packet && /* we are doing a segment selection during playback */

1222 c->cur_seq_no >= pls->start_seq_no &&

1223 c->cur_seq_no < pls->start_seq_no + pls->n_segments)

1224 /* While spec 3.4.3 says that we cannot assume anything about the

1225 * content at the same sequence number on different playlists,

1226 * in practice this seems to work and doing it otherwise would

1227 * require us to download a segment to inspect its timestamps. */

1228 return c->cur_seq_no;

1229

1230 /* If this is a live stream with more than 3 segments, start at the

1231 * third last segment. */

1232 if (pls->n_segments > 3)

1233 return pls->start_seq_no + pls->n_segments - 3;

1234 }

1235

1236 /* Otherwise just start on the first segment. */

1237 return pls->start_seq_no;

1238 }

1239

1240 static int hls_read_header(AVFormatContext *s)

1241 {

1242 URLContext *u = (s->flags & AVFMT_FLAG_CUSTOM_IO) ? NULL : s->pb->opaque;

1243 HLSContext *c = s->priv_data;

1244 int ret = 0, i, j, stream_offset = 0;

1245

1246 c->interrupt_callback = &s->interrupt_callback;

1247

1248 c->first_packet = 1;

1249 c->first_timestamp = AV_NOPTS_VALUE;

1250 c->cur_timestamp = AV_NOPTS_VALUE;

1251

1252 // if the URL context is good, read important options we must broker later

1253 if (u && u->prot->priv_data_class) {

1254 // get the previous user agent & set back to null if string size is zero

1255 av_freep(&c->user_agent);

1256 av_opt_get(u->priv_data, "user-agent", 0, (uint8_t**)&(c->user_agent));

1257 if (c->user_agent && !strlen(c->user_agent))

1258 av_freep(&c->user_agent);

1259

1260 // get the previous cookies & set back to null if string size is zero

1261 av_freep(&c->cookies);

1262 av_opt_get(u->priv_data, "cookies", 0, (uint8_t**)&(c->cookies));

1263 if (c->cookies && !strlen(c->cookies))

1264 av_freep(&c->cookies);

1265

1266 // get the previous headers & set back to null if string size is zero

1267 av_freep(&c->headers);

1268 av_opt_get(u->priv_data, "headers", 0, (uint8_t**)&(c->headers));

1269 if (c->headers && !strlen(c->headers))

1270 av_freep(&c->headers);

1271 }

1272

1273 if ((ret = parse_playlist(c, s->filename, NULL, s->pb)) < 0)

1274 goto fail;

1275

1276 if (c->n_variants == 0) {

1277 av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");

1278 ret = AVERROR_EOF;

1279 goto fail;

1280 }

1281 /* If the playlist only contained playlists (Master Playlist),

1282 * parse each individual playlist. */

1283 if (c->n_playlists > 1 || c->playlists[0]->n_segments == 0) {

1284 for (i = 0; i < c->n_playlists; i++) {

1285 struct playlist *pls = c->playlists[i];

1286 if ((ret = parse_playlist(c, pls->url, pls, NULL)) < 0)

1287 goto fail;

1288 }

1289 }

1290

1291 if (c->variants[0]->playlists[0]->n_segments == 0) {

1292 av_log(NULL, AV_LOG_WARNING, "Empty playlist\n");

1293 ret = AVERROR_EOF;

1294 goto fail;

1295 }

1296

1297 /* If this isn't a live stream, calculate the total duration of the

1298 * stream. */

1299 if (c->variants[0]->playlists[0]->finished) {

1300 int64_t duration = 0;

1301 for (i = 0; i < c->variants[0]->playlists[0]->n_segments; i++)

1302 duration += c->variants[0]->playlists[0]->segments[i]->duration;

1303 s->duration = duration;

1304 }

1305

1306 /* Associate renditions with variants */

1307 for (i = 0; i < c->n_variants; i++) {

1308 struct variant *var = c->variants[i];

1309

1310 if (var->audio_group[0])

1311 add_renditions_to_variant(c, var, AVMEDIA_TYPE_AUDIO, var->audio_group);

1312 if (var->video_group[0])

1313 add_renditions_to_variant(c, var, AVMEDIA_TYPE_VIDEO, var->video_group);

1314 if (var->subtitles_group[0])

1315 add_renditions_to_variant(c, var, AVMEDIA_TYPE_SUBTITLE, var->subtitles_group);

1316 }

1317

1318 /* Open the demuxer for each playlist */

1319 for (i = 0; i < c->n_playlists; i++) {

1320 struct playlist *pls = c->playlists[i];

1321 AVInputFormat *in_fmt = NULL;

1322

1323 if (!(pls->ctx = avformat_alloc_context())) {

1324 ret = AVERROR(ENOMEM);

1325 goto fail;

1326 }

1327

1328 if (pls->n_segments == 0)

1329 continue;

1330

1331 pls->index = i;

1332 pls->needed = 1;

1333 pls->parent = s;

1334 pls->cur_seq_no = select_cur_seq_no(c, pls);

1335

1336 pls->read_buffer = av_malloc(INITIAL_BUFFER_SIZE);

1337 ffio_init_context(&pls->pb, pls->read_buffer, INITIAL_BUFFER_SIZE, 0, pls,

1338 read_data, NULL, NULL);

1339 pls->pb.seekable = 0;

1340 ret = av_probe_input_buffer(&pls->pb, &in_fmt, pls->segments[0]->url,

1341 NULL, 0, 0);

1342 if (ret < 0) {

1343 /* Free the ctx - it isn't initialized properly at this point,

1344 * so avformat_close_input shouldn't be called. If

1345 * avformat_open_input fails below, it frees and zeros the

1346 * context, so it doesn't need any special treatment like this. */

1347 av_log(s, AV_LOG_ERROR, "Error when loading first segment '%s'\n", pls->segments[0]->url);

1348 avformat_free_context(pls->ctx);

1349 pls->ctx = NULL;

1350 goto fail;

1351 }

1352 pls->ctx->pb = &pls->pb;

1353 pls->stream_offset = stream_offset;

1354

1355 if ((ret = ff_copy_whitelists(pls->ctx, s)) < 0)

1356 goto fail;

1357

1358 ret = avformat_open_input(&pls->ctx, pls->segments[0]->url, in_fmt, NULL);

1359 if (ret < 0)

1360 goto fail;

1361

1362 if (pls->id3_deferred_extra && pls->ctx->nb_streams == 1) {

1363 ff_id3v2_parse_apic(pls->ctx, &pls->id3_deferred_extra);

1364 avformat_queue_attached_pictures(pls->ctx);

1365 ff_id3v2_free_extra_meta(&pls->id3_deferred_extra);

1366 pls->id3_deferred_extra = NULL;

1367 }

1368

1369 pls->ctx->ctx_flags &= ~AVFMTCTX_NOHEADER;

1370 ret = avformat_find_stream_info(pls->ctx, NULL);

1371 if (ret < 0)

1372 goto fail;

1373

1374 if (pls->is_id3_timestamped == -1)

1375 av_log(s, AV_LOG_WARNING, "No expected HTTP requests have been made\n");

1376

1377 /* Create new AVStreams for each stream in this playlist */

1378 for (j = 0; j < pls->ctx->nb_streams; j++) {

1379 AVStream *st = avformat_new_stream(s, NULL);

1380 AVStream *ist = pls->ctx->streams[j];

1381 if (!st) {

1382 ret = AVERROR(ENOMEM);

1383 goto fail;

1384 }

1385 st->id = i;

1386

1387 avcodec_copy_context(st->codec, pls->ctx->streams[j]->codec);

1388

1389 if (pls->is_id3_timestamped) /* custom timestamps via id3 */

1390 avpriv_set_pts_info(st, 33, 1, MPEG_TIME_BASE);

1391 else

1392 avpriv_set_pts_info(st, ist->pts_wrap_bits, ist->time_base.num, ist->time_base.den);

1393 }

1394

1395 add_metadata_from_renditions(s, pls, AVMEDIA_TYPE_AUDIO);

1396 add_metadata_from_renditions(s, pls, AVMEDIA_TYPE_VIDEO);

1397 add_metadata_from_renditions(s, pls, AVMEDIA_TYPE_SUBTITLE);

1398

1399 stream_offset += pls->ctx->nb_streams;

1400 }

1401

1402 /* Create a program for each variant */

1403 for (i = 0; i < c->n_variants; i++) {

1404 struct variant *v = c->variants[i];

1405 AVProgram *program;

1406

1407 program = av_new_program(s, i);

1408 if (!program)

1409 goto fail;

1410 av_dict_set_int(&program->metadata, "variant_bitrate", v->bandwidth, 0);

1411

1412 for (j = 0; j < v->n_playlists; j++) {

1413 struct playlist *pls = v->playlists[j];

1414 int is_shared = playlist_in_multiple_variants(c, pls);

1415 int k;

1416

1417 for (k = 0; k < pls->ctx->nb_streams; k++) {

1418 struct AVStream *st = s->streams[pls->stream_offset + k];

1419

1420 ff_program_add_stream_index(s, i, pls->stream_offset + k);

1421

1422 /* Set variant_bitrate for streams unique to this variant */

1423 if (!is_shared && v->bandwidth)

1424 av_dict_set_int(&st->metadata, "variant_bitrate", v->bandwidth, 0);

1425 }

1426 }

1427 }

1428

1429 return 0;

1430 fail:

1431 free_playlist_list(c);

1432 free_variant_list(c);

1433 free_rendition_list(c);

1434 return ret;

1435 }

1436

1437 static int recheck_discard_flags(AVFormatContext *s, int first)

1438 {

1439 HLSContext *c = s->priv_data;

1440 int i, changed = 0;

1441

1442 /* Check if any new streams are needed */

1443 for (i = 0; i < c->n_playlists; i++)

1444 c->playlists[i]->cur_needed = 0;

1445

1446 for (i = 0; i < s->nb_streams; i++) {

1447 AVStream *st = s->streams[i];

1448 struct playlist *pls = c->playlists[s->streams[i]->id];

1449 if (st->discard < AVDISCARD_ALL)

1450 pls->cur_needed = 1;

1451 }

1452 for (i = 0; i < c->n_playlists; i++) {

1453 struct playlist *pls = c->playlists[i];

1454 if (pls->cur_needed && !pls->needed) {

1455 pls->needed = 1;

1456 changed = 1;

1457 pls->cur_seq_no = select_cur_seq_no(c, pls);

1458 pls->pb.eof_reached = 0;

1459 if (c->cur_timestamp != AV_NOPTS_VALUE) {

1460 /* catch up */

1461 pls->seek_timestamp = c->cur_timestamp;

1462 pls->seek_flags = AVSEEK_FLAG_ANY;

1463 pls->seek_stream_index = -1;

1464 }

1465 av_log(s, AV_LOG_INFO, "Now receiving playlist %d, segment %d\n", i, pls->cur_seq_no);

1466 } else if (first && !pls->cur_needed && pls->needed) {

1467 if (pls->input)

1468 ffurl_close(pls->input);

1469 pls->input = NULL;

1470 pls->needed = 0;

1471 changed = 1;

1472 av_log(s, AV_LOG_INFO, "No longer receiving playlist %d\n", i);

1473 }

1474 }

1475 return changed;

1476 }

1477

1478 static void fill_timing_for_id3_timestamped_stream(struct playlist *pls)

1479 {

1480 if (pls->id3_offset >= 0) {

1481 pls->pkt.dts = pls->id3_mpegts_timestamp +

1482 av_rescale_q(pls->id3_offset,

1483 pls->ctx->streams[pls->pkt.stream_index]->time_base,

1484 MPEG_TIME_BASE_Q);

1485 if (pls->pkt.duration)

1486 pls->id3_offset += pls->pkt.duration;

1487 else

1488 pls->id3_offset = -1;

1489 } else {

1490 /* there have been packets with unknown duration

1491 * since the last id3 tag, should not normally happen */

1492 pls->pkt.dts = AV_NOPTS_VALUE;

1493 }

1494

1495 if (pls->pkt.duration)

1496 pls->pkt.duration = av_rescale_q(pls->pkt.duration,

1497 pls->ctx->streams[pls->pkt.stream_index]->time_base,

1498 MPEG_TIME_BASE_Q);

1499

1500 pls->pkt.pts = AV_NOPTS_VALUE;

1501 }

1502

1503 static AVRational get_timebase(struct playlist *pls)

1504 {

1505 if (pls->is_id3_timestamped)

1506 return MPEG_TIME_BASE_Q;

1507

1508 return pls->ctx->streams[pls->pkt.stream_index]->time_base;

1509 }

1510

1511 static int compare_ts_with_wrapdetect(int64_t ts_a, struct playlist *pls_a,

1512 int64_t ts_b, struct playlist *pls_b)

1513 {

1514 int64_t scaled_ts_a = av_rescale_q(ts_a, get_timebase(pls_a), MPEG_TIME_BASE_Q);

1515 int64_t scaled_ts_b = av_rescale_q(ts_b, get_timebase(pls_b), MPEG_TIME_BASE_Q);

1516

1517 return av_compare_mod(scaled_ts_a, scaled_ts_b, 1LL << 33);

1518 }

1519

1520 static int hls_read_packet(AVFormatContext *s, AVPacket *pkt)

1521 {

1522 HLSContext *c = s->priv_data;

1523 int ret, i, minplaylist = -1;

1524

1525 recheck_discard_flags(s, c->first_packet);

1526

1527 for (i = 0; i < c->n_playlists; i++) {

1528 struct playlist *pls = c->playlists[i];

1529 /* Make sure we've got one buffered packet from each open playlist

1530 * stream */

1531 if (pls->needed && !pls->pkt.data) {

1532 while (1) {

1533 int64_t ts_diff;

1534 AVRational tb;

1535 ret = av_read_frame(pls->ctx, &pls->pkt);

1536 if (ret < 0) {

1537 if (!avio_feof(&pls->pb) && ret != AVERROR_EOF)

1538 return ret;

1539 reset_packet(&pls->pkt);

1540 break;

1541 } else {

1542 /* stream_index check prevents matching picture attachments etc. */

1543 if (pls->is_id3_timestamped && pls->pkt.stream_index == 0) {

1544 /* audio elementary streams are id3 timestamped */

1545 fill_timing_for_id3_timestamped_stream(pls);

1546 }

1547

1548 if (c->first_timestamp == AV_NOPTS_VALUE &&

1549 pls->pkt.dts != AV_NOPTS_VALUE)

1550 c->first_timestamp = av_rescale_q(pls->pkt.dts,

1551 get_timebase(pls), AV_TIME_BASE_Q);

1552 }

1553

1554 if (pls->seek_timestamp == AV_NOPTS_VALUE)

1555 break;

1556

1557 if (pls->seek_stream_index < 0 ||

1558 pls->seek_stream_index == pls->pkt.stream_index) {

1559

1560 if (pls->pkt.dts == AV_NOPTS_VALUE) {

1561 pls->seek_timestamp = AV_NOPTS_VALUE;

1562 break;

1563 }

1564

1565 tb = get_timebase(pls);

1566 ts_diff = av_rescale_rnd(pls->pkt.dts, AV_TIME_BASE,

1567 tb.den, AV_ROUND_DOWN) -

1568 pls->seek_timestamp;

1569 if (ts_diff >= 0 && (pls->seek_flags & AVSEEK_FLAG_ANY ||

1570 pls->pkt.flags & AV_PKT_FLAG_KEY)) {

1571 pls->seek_timestamp = AV_NOPTS_VALUE;

1572 break;

1573 }

1574 }

1575 av_free_packet(&pls->pkt);

1576 reset_packet(&pls->pkt);

1577 }

1578 }

1579 /* Check if this stream has the packet with the lowest dts */

1580 if (pls->pkt.data) {

1581 struct playlist *minpls = minplaylist < 0 ?

1582 NULL : c->playlists[minplaylist];

1583 if (minplaylist < 0) {

1584 minplaylist = i;

1585 } else {

1586 int64_t dts = pls->pkt.dts;

1587 int64_t mindts = minpls->pkt.dts;

1588

1589 if (dts == AV_NOPTS_VALUE ||

1590 (mindts != AV_NOPTS_VALUE && compare_ts_with_wrapdetect(dts, pls, mindts, minpls) < 0))

1591 minplaylist = i;

1592 }

1593 }

1594 }

1595

1596 /* If we got a packet, return it */

1597 if (minplaylist >= 0) {

1598 struct playlist *pls = c->playlists[minplaylist];

1599 *pkt = pls->pkt;

1600 pkt->stream_index += pls->stream_offset;

1601 reset_packet(&c->playlists[minplaylist]->pkt);

1602

1603 if (pkt->dts != AV_NOPTS_VALUE)

1604 c->cur_timestamp = av_rescale_q(pkt->dts,

1605 pls->ctx->streams[pls->pkt.stream_index]->time_base,

1606 AV_TIME_BASE_Q);

1607

1608 return 0;

1609 }

1610 return AVERROR_EOF;

1611 }

1612

1613 static int hls_close(AVFormatContext *s)

1614 {

1615 HLSContext *c = s->priv_data;

1616

1617 free_playlist_list(c);

1618 free_variant_list(c);

1619 free_rendition_list(c);

1620 return 0;

1621 }

1622

1623 static int hls_read_seek(AVFormatContext *s, int stream_index,

1624 int64_t timestamp, int flags)

1625 {

1626 HLSContext *c = s->priv_data;

1627 struct playlist *seek_pls = NULL;

1628 int i, seq_no;

1629 int64_t first_timestamp, seek_timestamp, duration;

1630

1631 if ((flags & AVSEEK_FLAG_BYTE) ||

1632 !(c->variants[0]->playlists[0]->finished || c->variants[0]->playlists[0]->type == PLS_TYPE_EVENT))

1633 return AVERROR(ENOSYS);

1634

1635 first_timestamp = c->first_timestamp == AV_NOPTS_VALUE ?

1636 0 : c->first_timestamp;

1637

1638 seek_timestamp = av_rescale_rnd(timestamp, AV_TIME_BASE,

1639 s->streams[stream_index]->time_base.den,

1640 flags & AVSEEK_FLAG_BACKWARD ?

1641 AV_ROUND_DOWN : AV_ROUND_UP);

1642

1643 duration = s->duration == AV_NOPTS_VALUE ?

1644 0 : s->duration;

1645

1646 if (0 < duration && duration < seek_timestamp - first_timestamp)

1647 return AVERROR(EIO);

1648

1649 /* find the playlist with the specified stream */

1650 for (i = 0; i < c->n_playlists; i++) {

1651 struct playlist *pls = c->playlists[i];

1652 if (stream_index >= pls->stream_offset &&

1653 stream_index - pls->stream_offset < pls->ctx->nb_streams) {

1654 seek_pls = pls;

1655 break;

1656 }

1657 }

1658 /* check if the timestamp is valid for the playlist with the

1659 * specified stream index */

1660 if (!seek_pls || !find_timestamp_in_playlist(c, seek_pls, seek_timestamp, &seq_no))

1661 return AVERROR(EIO);

1662

1663 /* set segment now so we do not need to search again below */

1664 seek_pls->cur_seq_no = seq_no;

1665 seek_pls->seek_stream_index = stream_index - seek_pls->stream_offset;

1666

1667 for (i = 0; i < c->n_playlists; i++) {

1668 /* Reset reading */

1669 struct playlist *pls = c->playlists[i];

1670 if (pls->input) {

1671 ffurl_close(pls->input);

1672 pls->input = NULL;

1673 }

1674 av_free_packet(&pls->pkt);

1675 reset_packet(&pls->pkt);

1676 pls->pb.eof_reached = 0;

1677 /* Clear any buffered data */

1678 pls->pb.buf_end = pls->pb.buf_ptr = pls->pb.buffer;

1679 /* Reset the pos, to let the mpegts demuxer know we've seeked. */

1680 pls->pb.pos = 0;

1681 /* Flush the packet queue of the subdemuxer. */

1682 ff_read_frame_flush(pls->ctx);

1683

1684 pls->seek_timestamp = seek_timestamp;

1685 pls->seek_flags = flags;

1686

1687 if (pls != seek_pls) {

1688 /* set closest segment seq_no for playlists not handled above */

1689 find_timestamp_in_playlist(c, pls, seek_timestamp, &pls->cur_seq_no);

1690 /* seek the playlist to the given position without taking

1691 * keyframes into account since this playlist does not have the

1692 * specified stream where we should look for the keyframes */

1693 pls->seek_stream_index = -1;

1694 pls->seek_flags |= AVSEEK_FLAG_ANY;

1695 }

1696 }

1697

1698 c->cur_timestamp = seek_timestamp;

1699

1700 return 0;

1701 }

1702

1703 static int hls_probe(AVProbeData *p)

1704 {

1705 /* Require #EXTM3U at the start, and either one of the ones below

1706 * somewhere for a proper match. */

1707 if (strncmp(p->buf, "#EXTM3U", 7))

1708 return 0;

1709 if (strstr(p->buf, "#EXT-X-STREAM-INF:") ||

1710 strstr(p->buf, "#EXT-X-TARGETDURATION:") ||

1711 strstr(p->buf, "#EXT-X-MEDIA-SEQUENCE:"))

1712 return AVPROBE_SCORE_MAX;

1713 return 0;

1714 }

1715

1716 AVInputFormat ff_hls_demuxer = {

1717 .name = "hls,applehttp",

1718 .long_name = NULL_IF_CONFIG_SMALL("Apple HTTP Live Streaming"),

1719 .priv_data_size = sizeof(HLSContext),

1720 .read_probe = hls_probe,

1721 .read_header = hls_read_header,

1722 .read_packet = hls_read_packet,

1723 .read_close = hls_close,

1724 .read_seek = hls_read_seek,

1725 };

Generated on Sun Mar 8 2015 02:35:09 for FFmpeg by doxygen 1.8.2