FFmpeg: libavformat/nsvdec.c Source File

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libavformat

nsvdec.c

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1 /*

2 * NSV demuxer

4 *

5 * first version by Francois Revol <revol@free.fr>

6 *

7 * This file is part of FFmpeg.

8 *

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

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

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

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

13 *

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

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

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

17 * Lesser General Public License for more details.

18 *

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

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

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

22 */

24 #include "libavutil/attributes.h"

25 #include "libavutil/mathematics.h"

26 #include "avformat.h"

27 #include "internal.h"

28 #include "libavutil/dict.h"

29 #include "libavutil/intreadwrite.h"

31 /* max bytes to crawl for trying to resync

32 * stupid streaming servers don't start at chunk boundaries...

33 */

34 #define NSV_MAX_RESYNC (500*1024)

35 #define NSV_MAX_RESYNC_TRIES 300

37 /*

38 * References:

39 * (1) http://www.multimedia.cx/nsv-format.txt

40 * seems someone came to the same conclusions as me, and updated it:

41 * (2) http://www.stud.ktu.lt/~vitslav/nsv/nsv-format.txt

42 * http://www.stud.ktu.lt/~vitslav/nsv/

43 * official docs

44 * (3) http://ultravox.aol.com/NSVFormat.rtf

45 * Sample files:

46 * (S1) http://www.nullsoft.com/nsv/samples/

47 * http://www.nullsoft.com/nsv/samples/faster.nsv

48 * http://streamripper.sourceforge.net/openbb/read.php?TID=492&page=4

49 */

51 /*

52 * notes on the header (Francois Revol):

53 *

54 * It is followed by strings, then a table, but nothing tells

55 * where the table begins according to (1). After checking faster.nsv,

56 * I believe NVSf[16-19] gives the size of the strings data

57 * (that is the offset of the data table after the header).

58 * After checking all samples from (S1) all confirms this.

59 *

60 * Then, about NSVf[12-15], faster.nsf has 179700. When veiwing it in VLC,

61 * I noticed there was about 1 NVSs chunk/s, so I ran

62 * strings faster.nsv | grep NSVs | wc -l

63 * which gave me 180. That leads me to think that NSVf[12-15] might be the

64 * file length in milliseconds.

65 * Let's try that:

66 * for f in *.nsv; do HTIME="$(od -t x4 "$f" | head -1 | sed 's/.* //')"; echo "'$f' $((0x$HTIME))s = $((0x$HTIME/1000/60)):$((0x$HTIME/1000%60))"; done

67 * except for nstrailer (which doesn't have an NSVf header), it repports correct time.

68 *

69 * nsvtrailer.nsv (S1) does not have any NSVf header, only NSVs chunks,

70 * so the header seems to not be mandatory. (for streaming).

71 *

72 * index slice duration check (excepts nsvtrailer.nsv):

73 * for f in [^n]*.nsv; do DUR="$(ffmpeg -i "$f" 2>/dev/null | grep 'NSVf duration' | cut -d ' ' -f 4)"; IC="$(ffmpeg -i "$f" 2>/dev/null | grep 'INDEX ENTRIES' | cut -d ' ' -f 2)"; echo "duration $DUR, slite time $(($DUR/$IC))"; done

74 */

76 /*

77 * TODO:

78 * - handle timestamps !!!

79 * - use index

80 * - mime-type in probe()

81 * - seek

82 */

84 #if 0

85 struct NSVf_header {

86 uint32_t chunk_tag; /* 'NSVf' */

87 uint32_t chunk_size;

88 uint32_t file_size; /* max 4GB ??? no one learns anything it seems :^) */

89 uint32_t file_length; //unknown1; /* what about MSB of file_size ? */

90 uint32_t info_strings_size; /* size of the info strings */ //unknown2;

91 uint32_t table_entries;

92 uint32_t table_entries_used; /* the left ones should be -1 */

93 };

95 struct NSVs_header {

96 uint32_t chunk_tag; /* 'NSVs' */

97 uint32_t v4cc; /* or 'NONE' */

98 uint32_t a4cc; /* or 'NONE' */

99 uint16_t vwidth; /* av_assert0(vwidth%16==0) */

100 uint16_t vheight; /* av_assert0(vheight%16==0) */

101 uint8_t framerate; /* value = (framerate&0x80)?frtable[frameratex0x7f]:framerate */

102 uint16_t unknown;

103 };

104

105 struct nsv_avchunk_header {

106 uint8_t vchunk_size_lsb;

107 uint16_t vchunk_size_msb; /* value = (vchunk_size_msb << 4) | (vchunk_size_lsb >> 4) */

108 uint16_t achunk_size;

109 };

110

111 struct nsv_pcm_header {

112 uint8_t bits_per_sample;

113 uint8_t channel_count;

114 uint16_t sample_rate;

115 };

116 #endif

117

118 /* variation from avi.h */

119 /*typedef struct CodecTag {

120 int id;

121 unsigned int tag;

122 } CodecTag;*/

123

124 /* tags */

125

126 #define T_NSVF MKTAG('N', 'S', 'V', 'f') /* file header */

127 #define T_NSVS MKTAG('N', 'S', 'V', 's') /* chunk header */

128 #define T_TOC2 MKTAG('T', 'O', 'C', '2') /* extra index marker */

129 #define T_NONE MKTAG('N', 'O', 'N', 'E') /* null a/v 4CC */

130 #define T_SUBT MKTAG('S', 'U', 'B', 'T') /* subtitle aux data */

131 #define T_ASYN MKTAG('A', 'S', 'Y', 'N') /* async a/v aux marker */

132 #define T_KEYF MKTAG('K', 'E', 'Y', 'F') /* video keyframe aux marker (addition) */

133

134 #define TB_NSVF MKBETAG('N', 'S', 'V', 'f')

135 #define TB_NSVS MKBETAG('N', 'S', 'V', 's')

136

137 /* hardcoded stream indexes */

138 #define NSV_ST_VIDEO 0

139 #define NSV_ST_AUDIO 1

140 #define NSV_ST_SUBT 2

141

142 enum NSVStatus {

143 NSV_UNSYNC,

144 NSV_FOUND_NSVF,

145 NSV_HAS_READ_NSVF,

146 NSV_FOUND_NSVS,

147 NSV_HAS_READ_NSVS,

148 NSV_FOUND_BEEF,

149 NSV_GOT_VIDEO,

150 NSV_GOT_AUDIO,

151 };

152

153 typedef struct NSVStream {

154 int frame_offset; /* current frame (video) or byte (audio) counter

155 (used to compute the pts) */

156 int scale;

157 int rate;

158 int sample_size; /* audio only data */

159 int start;

160

161 int new_frame_offset; /* temporary storage (used during seek) */

162 int cum_len; /* temporary storage (used during seek) */

163 } NSVStream;

164

165 typedef struct NSVContext {

166 int base_offset;

167 int NSVf_end;

168 uint32_t *nsvs_file_offset;

169 int index_entries;

170 enum NSVStatus state;

171 AVPacket ahead[2]; /* [v, a] if .data is !NULL there is something */

172 /* cached */

173 int64_t duration;

174 uint32_t vtag, atag;

175 uint16_t vwidth, vheight;

176 int16_t avsync;

177 AVRational framerate;

178 uint32_t *nsvs_timestamps;

179 //DVDemuxContext* dv_demux;

180 } NSVContext;

181

182 static const AVCodecTag nsv_codec_video_tags[] = {

183 { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', ' ') },

184 { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '0') },

185 { AV_CODEC_ID_VP3, MKTAG('V', 'P', '3', '1') },

186 { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', ' ') },

187 { AV_CODEC_ID_VP5, MKTAG('V', 'P', '5', '0') },

188 { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', ' ') },

189 { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '0') },

190 { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '1') },

191 { AV_CODEC_ID_VP6, MKTAG('V', 'P', '6', '2') },

192 { AV_CODEC_ID_VP8, MKTAG('V', 'P', '8', '0') },

193 /*

194 { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', ' ') },

195 { AV_CODEC_ID_VP4, MKTAG('V', 'P', '4', '0') },

196 */

197 { AV_CODEC_ID_MPEG4, MKTAG('X', 'V', 'I', 'D') }, /* cf sample xvid decoder from nsv_codec_sdk.zip */

198 { AV_CODEC_ID_RAWVIDEO, MKTAG('R', 'G', 'B', '3') },

199 { AV_CODEC_ID_NONE, 0 },

200 };

201

202 static const AVCodecTag nsv_codec_audio_tags[] = {

203 { AV_CODEC_ID_MP3, MKTAG('M', 'P', '3', ' ') },

204 { AV_CODEC_ID_AAC, MKTAG('A', 'A', 'C', ' ') },

205 { AV_CODEC_ID_AAC, MKTAG('A', 'A', 'C', 'P') },

206 { AV_CODEC_ID_AAC, MKTAG('V', 'L', 'B', ' ') },

207 { AV_CODEC_ID_SPEEX, MKTAG('S', 'P', 'X', ' ') },

208 { AV_CODEC_ID_PCM_U16LE, MKTAG('P', 'C', 'M', ' ') },

209 { AV_CODEC_ID_NONE, 0 },

210 };

211

212 //static int nsv_load_index(AVFormatContext *s);

213 static int nsv_read_chunk(AVFormatContext *s, int fill_header);

214

215 #define print_tag(str, tag, size) \

216 av_dlog(NULL, "%s: tag=%c%c%c%c\n", \

217 str, tag & 0xff, \

218 (tag >> 8) & 0xff, \

219 (tag >> 16) & 0xff, \

220 (tag >> 24) & 0xff);

221

222 /* try to find something we recognize, and set the state accordingly */

223 static int nsv_resync(AVFormatContext *s)

224 {

225 NSVContext *nsv = s->priv_data;

226 AVIOContext *pb = s->pb;

227 uint32_t v = 0;

228 int i;

229

230 av_dlog(s, "%s(), offset = %"PRId64", state = %d\n", __FUNCTION__, avio_tell(pb), nsv->state);

231

232 //nsv->state = NSV_UNSYNC;

233

234 for (i = 0; i < NSV_MAX_RESYNC; i++) {

235 if (avio_feof(pb)) {

236 av_dlog(s, "NSV EOF\n");

237 nsv->state = NSV_UNSYNC;

238 return -1;

239 }

240 v <<= 8;

241 v |= avio_r8(pb);

242 if (i < 8) {

243 av_dlog(s, "NSV resync: [%d] = %02x\n", i, v & 0x0FF);

244 }

245

246 if ((v & 0x0000ffff) == 0xefbe) { /* BEEF */

247 av_dlog(s, "NSV resynced on BEEF after %d bytes\n", i+1);

248 nsv->state = NSV_FOUND_BEEF;

249 return 0;

250 }

251 /* we read as big-endian, thus the MK*BE* */

252 if (v == TB_NSVF) { /* NSVf */

253 av_dlog(s, "NSV resynced on NSVf after %d bytes\n", i+1);

254 nsv->state = NSV_FOUND_NSVF;

255 return 0;

256 }

257 if (v == MKBETAG('N', 'S', 'V', 's')) { /* NSVs */

258 av_dlog(s, "NSV resynced on NSVs after %d bytes\n", i+1);

259 nsv->state = NSV_FOUND_NSVS;

260 return 0;

261 }

262

263 }

264 av_dlog(s, "NSV sync lost\n");

265 return -1;

266 }

267

268 static int nsv_parse_NSVf_header(AVFormatContext *s)

269 {

270 NSVContext *nsv = s->priv_data;

271 AVIOContext *pb = s->pb;

272 unsigned int av_unused file_size;

273 unsigned int size;

274 int64_t duration;

275 int strings_size;

276 int table_entries;

277 int table_entries_used;

278

279 av_dlog(s, "%s()\n", __FUNCTION__);

280

281 nsv->state = NSV_UNSYNC; /* in case we fail */

282

283 size = avio_rl32(pb);

284 if (size < 28)

285 return -1;

286 nsv->NSVf_end = size;

287

288 //s->file_size = (uint32_t)avio_rl32(pb);

289 file_size = (uint32_t)avio_rl32(pb);

290 av_dlog(s, "NSV NSVf chunk_size %u\n", size);

291 av_dlog(s, "NSV NSVf file_size %u\n", file_size);

292

293 nsv->duration = duration = avio_rl32(pb); /* in ms */

294 av_dlog(s, "NSV NSVf duration %"PRId64" ms\n", duration);

295 // XXX: store it in AVStreams

296

297 strings_size = avio_rl32(pb);

298 table_entries = avio_rl32(pb);

299 table_entries_used = avio_rl32(pb);

300 av_dlog(s, "NSV NSVf info-strings size: %d, table entries: %d, bis %d\n",

301 strings_size, table_entries, table_entries_used);

302 if (avio_feof(pb))

303 return -1;

304

305 av_dlog(s, "NSV got header; filepos %"PRId64"\n", avio_tell(pb));

306

307 if (strings_size > 0) {

308 char *strings; /* last byte will be '0円' to play safe with str*() */

309 char *p, *endp;

310 char *token, *value;

311 char quote;

312

313 p = strings = av_mallocz((size_t)strings_size + 1);

314 if (!p)

315 return AVERROR(ENOMEM);

316 endp = strings + strings_size;

317 avio_read(pb, strings, strings_size);

318 while (p < endp) {

319 while (*p == ' ')

320 p++; /* strip out spaces */

321 if (p >= endp-2)

322 break;

323 token = p;

324 p = strchr(p, '=');

325 if (!p || p >= endp-2)

326 break;

327 *p++ = '0円';

328 quote = *p++;

329 value = p;

330 p = strchr(p, quote);

331 if (!p || p >= endp)

332 break;

333 *p++ = '0円';

334 av_dlog(s, "NSV NSVf INFO: %s='%s'\n", token, value);

335 av_dict_set(&s->metadata, token, value, 0);

336 }

337 av_free(strings);

338 }

339 if (avio_feof(pb))

340 return -1;

341

342 av_dlog(s, "NSV got infos; filepos %"PRId64"\n", avio_tell(pb));

343

344 if (table_entries_used > 0) {

345 int i;

346 nsv->index_entries = table_entries_used;

347 if((unsigned)table_entries_used >= UINT_MAX / sizeof(uint32_t))

348 return -1;

349 nsv->nsvs_file_offset = av_malloc((unsigned)table_entries_used * sizeof(uint32_t));

350 if (!nsv->nsvs_file_offset)

351 return AVERROR(ENOMEM);

352

353 for(i=0;i<table_entries_used;i++)

354 nsv->nsvs_file_offset[i] = avio_rl32(pb) + size;

355

356 if(table_entries > table_entries_used &&

357 avio_rl32(pb) == MKTAG('T','O','C','2')) {

358 nsv->nsvs_timestamps = av_malloc((unsigned)table_entries_used*sizeof(uint32_t));

359 if (!nsv->nsvs_timestamps)

360 return AVERROR(ENOMEM);

361 for(i=0;i<table_entries_used;i++) {

362 nsv->nsvs_timestamps[i] = avio_rl32(pb);

363 }

364 }

365 }

366

367 av_dlog(s, "NSV got index; filepos %"PRId64"\n", avio_tell(pb));

368

369 avio_seek(pb, nsv->base_offset + size, SEEK_SET); /* required for dumbdriving-271.nsv (2 extra bytes) */

370

371 if (avio_feof(pb))

372 return -1;

373 nsv->state = NSV_HAS_READ_NSVF;

374 return 0;

375 }

376

377 static int nsv_parse_NSVs_header(AVFormatContext *s)

378 {

379 NSVContext *nsv = s->priv_data;

380 AVIOContext *pb = s->pb;

381 uint32_t vtag, atag;

382 uint16_t vwidth, vheight;

383 AVRational framerate;

384 int i;

385 AVStream *st;

386 NSVStream *nst;

387 av_dlog(s, "%s()\n", __FUNCTION__);

388

389 vtag = avio_rl32(pb);

390 atag = avio_rl32(pb);

391 vwidth = avio_rl16(pb);

392 vheight = avio_rl16(pb);

393 i = avio_r8(pb);

394

395 av_dlog(s, "NSV NSVs framerate code %2x\n", i);

396 if(i&0x80) { /* odd way of giving native framerates from docs */

397 int t=(i & 0x7F)>>2;

398 if(t<16) framerate = (AVRational){1, t+1};

399 else framerate = (AVRational){t-15, 1};

400

401 if(i&1){

402 framerate.num *= 1000;

403 framerate.den *= 1001;

404 }

405

406 if((i&3)==3) framerate.num *= 24;

407 else if((i&3)==2) framerate.num *= 25;

408 else framerate.num *= 30;

409 }

410 else

411 framerate= (AVRational){i, 1};

412

413 nsv->avsync = avio_rl16(pb);

414 nsv->framerate = framerate;

415

416 print_tag("NSV NSVs vtag", vtag, 0);

417 print_tag("NSV NSVs atag", atag, 0);

418 av_dlog(s, "NSV NSVs vsize %dx%d\n", vwidth, vheight);

419

420 /* XXX change to ap != NULL ? */

421 if (s->nb_streams == 0) { /* streams not yet published, let's do that */

422 nsv->vtag = vtag;

423 nsv->atag = atag;

424 nsv->vwidth = vwidth;

425 nsv->vheight = vwidth;

426 if (vtag != T_NONE) {

427 int i;

428 st = avformat_new_stream(s, NULL);

429 if (!st)

430 goto fail;

431

432 st->id = NSV_ST_VIDEO;

433 nst = av_mallocz(sizeof(NSVStream));

434 if (!nst)

435 goto fail;

436 st->priv_data = nst;

437 st->codec->codec_type = AVMEDIA_TYPE_VIDEO;

438 st->codec->codec_tag = vtag;

439 st->codec->codec_id = ff_codec_get_id(nsv_codec_video_tags, vtag);

440 st->codec->width = vwidth;

441 st->codec->height = vheight;

442 st->codec->bits_per_coded_sample = 24; /* depth XXX */

443

444 avpriv_set_pts_info(st, 64, framerate.den, framerate.num);

445 st->start_time = 0;

446 st->duration = av_rescale(nsv->duration, framerate.num, 1000*framerate.den);

447

448 for(i=0;i<nsv->index_entries;i++) {

449 if(nsv->nsvs_timestamps) {

450 av_add_index_entry(st, nsv->nsvs_file_offset[i], nsv->nsvs_timestamps[i],

451 0, 0, AVINDEX_KEYFRAME);

452 } else {

453 int64_t ts = av_rescale(i*nsv->duration/nsv->index_entries, framerate.num, 1000*framerate.den);

454 av_add_index_entry(st, nsv->nsvs_file_offset[i], ts, 0, 0, AVINDEX_KEYFRAME);

455 }

456 }

457 }

458 if (atag != T_NONE) {

459 st = avformat_new_stream(s, NULL);

460 if (!st)

461 goto fail;

462

463 st->id = NSV_ST_AUDIO;

464 nst = av_mallocz(sizeof(NSVStream));

465 if (!nst)

466 goto fail;

467 st->priv_data = nst;

468 st->codec->codec_type = AVMEDIA_TYPE_AUDIO;

469 st->codec->codec_tag = atag;

470 st->codec->codec_id = ff_codec_get_id(nsv_codec_audio_tags, atag);

471

472 st->need_parsing = AVSTREAM_PARSE_FULL; /* for PCM we will read a chunk later and put correct info */

473

474 /* set timebase to common denominator of ms and framerate */

475 avpriv_set_pts_info(st, 64, 1, framerate.num*1000);

476 st->start_time = 0;

477 st->duration = (int64_t)nsv->duration * framerate.num;

478 }

479 } else {

480 if (nsv->vtag != vtag || nsv->atag != atag || nsv->vwidth != vwidth || nsv->vheight != vwidth) {

481 av_dlog(s, "NSV NSVs header values differ from the first one!!!\n");

482 //return -1;

483 }

484 }

485

486 nsv->state = NSV_HAS_READ_NSVS;

487 return 0;

488 fail:

489 /* XXX */

490 nsv->state = NSV_UNSYNC;

491 return -1;

492 }

493

494 static int nsv_read_header(AVFormatContext *s)

495 {

496 NSVContext *nsv = s->priv_data;

497 int i, err;

498

499 av_dlog(s, "%s()\n", __FUNCTION__);

500 av_dlog(s, "filename '%s'\n", s->filename);

501

502 nsv->state = NSV_UNSYNC;

503 nsv->ahead[0].data = nsv->ahead[1].data = NULL;

504

505 for (i = 0; i < NSV_MAX_RESYNC_TRIES; i++) {

506 if (nsv_resync(s) < 0)

507 return -1;

508 if (nsv->state == NSV_FOUND_NSVF) {

509 err = nsv_parse_NSVf_header(s);

510 if (err < 0)

511 return err;

512 }

513 /* we need the first NSVs also... */

514 if (nsv->state == NSV_FOUND_NSVS) {

515 err = nsv_parse_NSVs_header(s);

516 if (err < 0)

517 return err;

518 break; /* we just want the first one */

519 }

520 }

521 if (s->nb_streams < 1) /* no luck so far */

522 return -1;

523 /* now read the first chunk, so we can attempt to decode more info */

524 err = nsv_read_chunk(s, 1);

525

526 av_dlog(s, "parsed header\n");

527 return err;

528 }

529

530 static int nsv_read_chunk(AVFormatContext *s, int fill_header)

531 {

532 NSVContext *nsv = s->priv_data;

533 AVIOContext *pb = s->pb;

534 AVStream *st[2] = {NULL, NULL};

535 NSVStream *nst;

536 AVPacket *pkt;

537 int i, err = 0;

538 uint8_t auxcount; /* number of aux metadata, also 4 bits of vsize */

539 uint32_t vsize;

540 uint16_t asize;

541 uint16_t auxsize;

542 int ret;

543

544 av_dlog(s, "%s(%d)\n", __FUNCTION__, fill_header);

545

546 if (nsv->ahead[0].data || nsv->ahead[1].data)

547 return 0; //-1; /* hey! eat what you've in your plate first! */

548

549 null_chunk_retry:

550 if (avio_feof(pb))

551 return -1;

552

553 for (i = 0; i < NSV_MAX_RESYNC_TRIES && nsv->state < NSV_FOUND_NSVS && !err; i++)

554 err = nsv_resync(s);

555 if (err < 0)

556 return err;

557 if (nsv->state == NSV_FOUND_NSVS)

558 err = nsv_parse_NSVs_header(s);

559 if (err < 0)

560 return err;

561 if (nsv->state != NSV_HAS_READ_NSVS && nsv->state != NSV_FOUND_BEEF)

562 return -1;

563

564 auxcount = avio_r8(pb);

565 vsize = avio_rl16(pb);

566 asize = avio_rl16(pb);

567 vsize = (vsize << 4) | (auxcount >> 4);

568 auxcount &= 0x0f;

569 av_dlog(s, "NSV CHUNK %d aux, %u bytes video, %d bytes audio\n", auxcount, vsize, asize);

570 /* skip aux stuff */

571 for (i = 0; i < auxcount; i++) {

572 uint32_t av_unused auxtag;

573 auxsize = avio_rl16(pb);

574 auxtag = avio_rl32(pb);

575 av_dlog(s, "NSV aux data: '%c%c%c%c', %d bytes\n",

576 (auxtag & 0x0ff),

577 ((auxtag >> 8) & 0x0ff),

578 ((auxtag >> 16) & 0x0ff),

579 ((auxtag >> 24) & 0x0ff),

580 auxsize);

581 avio_skip(pb, auxsize);

582 vsize -= auxsize + sizeof(uint16_t) + sizeof(uint32_t); /* that's becoming braindead */

583 }

584

585 if (avio_feof(pb))

586 return -1;

587 if (!vsize && !asize) {

588 nsv->state = NSV_UNSYNC;

589 goto null_chunk_retry;

590 }

591

592 /* map back streams to v,a */

593 if (s->nb_streams > 0)

594 st[s->streams[0]->id] = s->streams[0];

595 if (s->nb_streams > 1)

596 st[s->streams[1]->id] = s->streams[1];

597

598 if (vsize && st[NSV_ST_VIDEO]) {

599 nst = st[NSV_ST_VIDEO]->priv_data;

600 pkt = &nsv->ahead[NSV_ST_VIDEO];

601 if ((ret = av_get_packet(pb, pkt, vsize)) < 0)

602 return ret;

603 pkt->stream_index = st[NSV_ST_VIDEO]->index;//NSV_ST_VIDEO;

604 pkt->dts = nst->frame_offset;

605 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */

606 for (i = 0; i < FFMIN(8, vsize); i++)

607 av_dlog(s, "NSV video: [%d] = %02x\n", i, pkt->data[i]);

608 }

609 if(st[NSV_ST_VIDEO])

610 ((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset++;

611

612 if (asize && st[NSV_ST_AUDIO]) {

613 nst = st[NSV_ST_AUDIO]->priv_data;

614 pkt = &nsv->ahead[NSV_ST_AUDIO];

615 /* read raw audio specific header on the first audio chunk... */

616 /* on ALL audio chunks ?? seems so! */

617 if (asize && st[NSV_ST_AUDIO]->codec->codec_tag == MKTAG('P', 'C', 'M', ' ')/* && fill_header*/) {

618 uint8_t bps;

619 uint8_t channels;

620 uint16_t samplerate;

621 bps = avio_r8(pb);

622 channels = avio_r8(pb);

623 samplerate = avio_rl16(pb);

624 if (!channels || !samplerate)

625 return AVERROR_INVALIDDATA;

626 asize-=4;

627 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);

628 if (fill_header) {

629 st[NSV_ST_AUDIO]->need_parsing = AVSTREAM_PARSE_NONE; /* we know everything */

630 if (bps != 16) {

631 av_dlog(s, "NSV AUDIO bit/sample != 16 (%d)!!!\n", bps);

632 }

633 bps /= channels; // ???

634 if (bps == 8)

635 st[NSV_ST_AUDIO]->codec->codec_id = AV_CODEC_ID_PCM_U8;

636 samplerate /= 4;/* UGH ??? XXX */

637 channels = 1;

638 st[NSV_ST_AUDIO]->codec->channels = channels;

639 st[NSV_ST_AUDIO]->codec->sample_rate = samplerate;

640 av_dlog(s, "NSV RAWAUDIO: bps %d, nchan %d, srate %d\n", bps, channels, samplerate);

641 }

642 }

643 if ((ret = av_get_packet(pb, pkt, asize)) < 0)

644 return ret;

645 pkt->stream_index = st[NSV_ST_AUDIO]->index;//NSV_ST_AUDIO;

646 pkt->flags |= nsv->state == NSV_HAS_READ_NSVS ? AV_PKT_FLAG_KEY : 0; /* keyframe only likely on a sync frame */

647 if( nsv->state == NSV_HAS_READ_NSVS && st[NSV_ST_VIDEO] ) {

648 /* on a nsvs frame we have new information on a/v sync */

649 pkt->dts = (((NSVStream*)st[NSV_ST_VIDEO]->priv_data)->frame_offset-1);

650 pkt->dts *= (int64_t)1000 * nsv->framerate.den;

651 pkt->dts += (int64_t)nsv->avsync * nsv->framerate.num;

652 av_dlog(s, "NSV AUDIO: sync:%d, dts:%"PRId64, nsv->avsync, pkt->dts);

653 }

654 nst->frame_offset++;

655 }

656

657 nsv->state = NSV_UNSYNC;

658 return 0;

659 }

660

661

662 static int nsv_read_packet(AVFormatContext *s, AVPacket *pkt)

663 {

664 NSVContext *nsv = s->priv_data;

665 int i, err = 0;

666

667 av_dlog(s, "%s()\n", __FUNCTION__);

668

669 /* in case we don't already have something to eat ... */

670 if (!nsv->ahead[0].data && !nsv->ahead[1].data)

671 err = nsv_read_chunk(s, 0);

672 if (err < 0)

673 return err;

674

675 /* now pick one of the plates */

676 for (i = 0; i < 2; i++) {

677 if (nsv->ahead[i].data) {

678 av_dlog(s, "%s: using cached packet[%d]\n", __FUNCTION__, i);

679 /* avoid the cost of new_packet + memcpy(->data) */

680 memcpy(pkt, &nsv->ahead[i], sizeof(AVPacket));

681 nsv->ahead[i].data = NULL; /* we ate that one */

682 return pkt->size;

683 }

684 }

685

686 /* this restaurant is not approvisionned :^] */

687 return -1;

688 }

689

690 static int nsv_read_seek(AVFormatContext *s, int stream_index, int64_t timestamp, int flags)

691 {

692 NSVContext *nsv = s->priv_data;

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

694 NSVStream *nst = st->priv_data;

695 int index;

696

697 index = av_index_search_timestamp(st, timestamp, flags);

698 if(index < 0)

699 return -1;

700

701 if (avio_seek(s->pb, st->index_entries[index].pos, SEEK_SET) < 0)

702 return -1;

703

704 nst->frame_offset = st->index_entries[index].timestamp;

705 nsv->state = NSV_UNSYNC;

706 return 0;

707 }

708

709 static int nsv_read_close(AVFormatContext *s)

710 {

711 NSVContext *nsv = s->priv_data;

712

713 av_freep(&nsv->nsvs_file_offset);

714 av_freep(&nsv->nsvs_timestamps);

715 if (nsv->ahead[0].data)

716 av_free_packet(&nsv->ahead[0]);

717 if (nsv->ahead[1].data)

718 av_free_packet(&nsv->ahead[1]);

719 return 0;

720 }

721

722 static int nsv_probe(AVProbeData *p)

723 {

724 int i, score = 0;

725

726 av_dlog(NULL, "nsv_probe(), buf_size %d\n", p->buf_size);

727 /* check file header */

728 /* streamed files might not have any header */

729 if (p->buf[0] == 'N' && p->buf[1] == 'S' &&

730 p->buf[2] == 'V' && (p->buf[3] == 'f' || p->buf[3] == 's'))

731 return AVPROBE_SCORE_MAX;

732 /* XXX: do streamed files always start at chunk boundary ?? */

733 /* or do we need to search NSVs in the byte stream ? */

734 /* seems the servers don't bother starting clean chunks... */

735 /* sometimes even the first header is at 9KB or something :^) */

736 for (i = 1; i < p->buf_size - 3; i++) {

737 if (AV_RL32(p->buf + i) == AV_RL32("NSVs")) {

738 /* Get the chunk size and check if at the end we are getting 0xBEEF */

739 int vsize = AV_RL24(p->buf+i+19) >> 4;

740 int asize = AV_RL16(p->buf+i+22);

741 int offset = i + 23 + asize + vsize + 1;

742 if (offset <= p->buf_size - 2 && AV_RL16(p->buf + offset) == 0xBEEF)

743 return 4*AVPROBE_SCORE_MAX/5;

744 score = AVPROBE_SCORE_MAX/5;

745 }

746 }

747 /* so we'll have more luck on extension... */

748 if (av_match_ext(p->filename, "nsv"))

749 return AVPROBE_SCORE_EXTENSION;

750 /* FIXME: add mime-type check */

751 return score;

752 }

753

754 AVInputFormat ff_nsv_demuxer = {

755 .name = "nsv",

756 .long_name = NULL_IF_CONFIG_SMALL("Nullsoft Streaming Video"),

757 .priv_data_size = sizeof(NSVContext),

758 .read_probe = nsv_probe,

759 .read_header = nsv_read_header,

760 .read_packet = nsv_read_packet,

761 .read_close = nsv_read_close,

762 .read_seek = nsv_read_seek,

763 };

Generated on Sun Mar 8 2015 02:35:11 for FFmpeg by doxygen 1.8.2