FFmpeg: libavformat/nutenc.c Source File

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libavformat

nutenc.c

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1 /*

2 * nut muxer

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 "libavutil/intreadwrite.h"

23 #include "libavutil/mathematics.h"

24 #include "libavutil/tree.h"

25 #include "libavutil/dict.h"

26 #include "libavutil/avassert.h"

27 #include "libavcodec/mpegaudiodata.h"

28 #include "nut.h"

29 #include "internal.h"

30 #include "avio_internal.h"

31 #include "riff.h"

33 static int find_expected_header(AVCodecContext *c, int size, int key_frame,

34 uint8_t out[64])

35 {

36 int sample_rate = c->sample_rate;

38 if (size > 4096)

39 return 0;

41 AV_WB24(out, 1);

43 if (c->codec_id == AV_CODEC_ID_MPEG4) {

44 if (key_frame) {

45 return 3;

46 } else {

47 out[3] = 0xB6;

48 return 4;

49 }

50 } else if (c->codec_id == AV_CODEC_ID_MPEG1VIDEO ||

51 c->codec_id == AV_CODEC_ID_MPEG2VIDEO) {

52 return 3;

53 } else if (c->codec_id == AV_CODEC_ID_H264) {

54 return 3;

55 } else if (c->codec_id == AV_CODEC_ID_MP3 ||

56 c->codec_id == AV_CODEC_ID_MP2) {

57 int lsf, mpeg25, sample_rate_index, bitrate_index, frame_size;

58 int layer = c->codec_id == AV_CODEC_ID_MP3 ? 3 : 2;

59 unsigned int header = 0xFFF00000;

61 lsf = sample_rate < (24000 + 32000) / 2;

62 mpeg25 = sample_rate < (12000 + 16000) / 2;

63 sample_rate <<= lsf + mpeg25;

64 if (sample_rate < (32000 + 44100) / 2) sample_rate_index = 2;

65 else if (sample_rate < (44100 + 48000) / 2) sample_rate_index = 0;

66 else sample_rate_index = 1;

68 sample_rate = avpriv_mpa_freq_tab[sample_rate_index] >> (lsf + mpeg25);

70 for (bitrate_index = 2; bitrate_index < 30; bitrate_index++) {

71 frame_size =

72 avpriv_mpa_bitrate_tab[lsf][layer - 1][bitrate_index >> 1];

73 frame_size = (frame_size * 144000) / (sample_rate << lsf) +

74 (bitrate_index & 1);

76 if (frame_size == size)

77 break;

78 }

80 header |= (!lsf) << 19;

81 header |= (4 - layer) << 17;

82 header |= 1 << 16; //no crc

83 AV_WB32(out, header);

84 if (size <= 0)

85 return 2; //we guess there is no crc, if there is one the user clearly does not care about overhead

86 if (bitrate_index == 30)

87 return -1; //something is wrong ...

89 header |= (bitrate_index >> 1) << 12;

90 header |= sample_rate_index << 10;

91 header |= (bitrate_index & 1) << 9;

93 return 2; //FIXME actually put the needed ones in build_elision_headers()

94 return 3; //we guess that the private bit is not set

95 //FIXME the above assumptions should be checked, if these turn out false too often something should be done

96 }

97 return 0;

98 }

100 static int find_header_idx(AVFormatContext *s, AVCodecContext *c, int size, int frame_type)

101 {

102 NUTContext *nut = s->priv_data;

103 uint8_t out[64];

104 int i;

105 int len = find_expected_header(c, size, frame_type, out);

106

107 for (i = 1; i < nut->header_count; i++) {

108 if (len == nut->header_len[i] && !memcmp(out, nut->header[i], len)) {

109 return i;

110 }

111 }

112

113 return 0;

114 }

115

116 static void build_elision_headers(AVFormatContext *s)

117 {

118 NUTContext *nut = s->priv_data;

119 int i;

120 //FIXME this is lame

121 //FIXME write a 2pass mode to find the maximal headers

122 static const uint8_t headers[][5] = {

123 { 3, 0x00, 0x00, 0x01 },

124 { 4, 0x00, 0x00, 0x01, 0xB6},

125 { 2, 0xFF, 0xFA }, //mp3+crc

126 { 2, 0xFF, 0xFB }, //mp3

127 { 2, 0xFF, 0xFC }, //mp2+crc

128 { 2, 0xFF, 0xFD }, //mp2

129 };

130

131 nut->header_count = 7;

132 for (i = 1; i < nut->header_count; i++) {

133 nut->header_len[i] = headers[i - 1][0];

134 nut->header[i] = &headers[i - 1][1];

135 }

136 }

137

138 static void build_frame_code(AVFormatContext *s)

139 {

140 NUTContext *nut = s->priv_data;

141 int key_frame, index, pred, stream_id;

142 int start = 1;

143 int end = 254;

144 int keyframe_0_esc = s->nb_streams > 2;

145 int pred_table[10];

146 FrameCode *ft;

147

148 ft = &nut->frame_code[start];

149 ft->flags = FLAG_CODED;

150 ft->size_mul = 1;

151 ft->pts_delta = 1;

152 start++;

153

154 if (keyframe_0_esc) {

155 /* keyframe = 0 escape */

156 FrameCode *ft = &nut->frame_code[start];

157 ft->flags = FLAG_STREAM_ID | FLAG_SIZE_MSB | FLAG_CODED_PTS;

158 ft->size_mul = 1;

159 start++;

160 }

161

162 for (stream_id = 0; stream_id < s->nb_streams; stream_id++) {

163 int start2 = start + (end - start) * stream_id / s->nb_streams;

164 int end2 = start + (end - start) * (stream_id + 1) / s->nb_streams;

165 AVCodecContext *codec = s->streams[stream_id]->codec;

166 int is_audio = codec->codec_type == AVMEDIA_TYPE_AUDIO;

167 int intra_only = /*codec->intra_only || */ is_audio;

168 int pred_count;

169 int frame_size = 0;

170

171 if (codec->codec_type == AVMEDIA_TYPE_AUDIO) {

172 frame_size = av_get_audio_frame_duration(codec, 0);

173 if (codec->codec_id == AV_CODEC_ID_VORBIS && !frame_size)

174 frame_size = 64;

175 } else {

176 AVRational f = av_div_q(codec->time_base, *nut->stream[stream_id].time_base);

177 if (f.den == 1 && f.num>0)

178 frame_size = f.num;

179 }

180 if (!frame_size)

181 frame_size = 1;

182

183 for (key_frame = 0; key_frame < 2; key_frame++) {

184 if (!intra_only || !keyframe_0_esc || key_frame != 0) {

185 FrameCode *ft = &nut->frame_code[start2];

186 ft->flags = FLAG_KEY * key_frame;

187 ft->flags |= FLAG_SIZE_MSB | FLAG_CODED_PTS;

188 ft->stream_id = stream_id;

189 ft->size_mul = 1;

190 if (is_audio)

191 ft->header_idx = find_header_idx(s, codec, -1, key_frame);

192 start2++;

193 }

194 }

195

196 key_frame = intra_only;

197 #if 1

198 if (is_audio) {

199 int frame_bytes = codec->frame_size * (int64_t)codec->bit_rate /

200 (8 * codec->sample_rate);

201 int pts;

202 for (pts = 0; pts < 2; pts++) {

203 for (pred = 0; pred < 2; pred++) {

204 FrameCode *ft = &nut->frame_code[start2];

205 ft->flags = FLAG_KEY * key_frame;

206 ft->stream_id = stream_id;

207 ft->size_mul = frame_bytes + 2;

208 ft->size_lsb = frame_bytes + pred;

209 ft->pts_delta = pts * frame_size;

210 ft->header_idx = find_header_idx(s, codec, frame_bytes + pred, key_frame);

211 start2++;

212 }

213 }

214 } else {

215 FrameCode *ft = &nut->frame_code[start2];

216 ft->flags = FLAG_KEY | FLAG_SIZE_MSB;

217 ft->stream_id = stream_id;

218 ft->size_mul = 1;

219 ft->pts_delta = frame_size;

220 start2++;

221 }

222 #endif

223

224 if (codec->has_b_frames) {

225 pred_count = 5;

226 pred_table[0] = -2;

227 pred_table[1] = -1;

228 pred_table[2] = 1;

229 pred_table[3] = 3;

230 pred_table[4] = 4;

231 } else if (codec->codec_id == AV_CODEC_ID_VORBIS) {

232 pred_count = 3;

233 pred_table[0] = 2;

234 pred_table[1] = 9;

235 pred_table[2] = 16;

236 } else {

237 pred_count = 1;

238 pred_table[0] = 1;

239 }

240

241 for (pred = 0; pred < pred_count; pred++) {

242 int start3 = start2 + (end2 - start2) * pred / pred_count;

243 int end3 = start2 + (end2 - start2) * (pred + 1) / pred_count;

244

245 pred_table[pred] *= frame_size;

246

247 for (index = start3; index < end3; index++) {

248 FrameCode *ft = &nut->frame_code[index];

249 ft->flags = FLAG_KEY * key_frame;

250 ft->flags |= FLAG_SIZE_MSB;

251 ft->stream_id = stream_id;

252 //FIXME use single byte size and pred from last

253 ft->size_mul = end3 - start3;

254 ft->size_lsb = index - start3;

255 ft->pts_delta = pred_table[pred];

256 if (is_audio)

257 ft->header_idx = find_header_idx(s, codec, -1, key_frame);

258 }

259 }

260 }

261 memmove(&nut->frame_code['N' + 1], &nut->frame_code['N'], sizeof(FrameCode) * (255 - 'N'));

262 nut->frame_code[0].flags =

263 nut->frame_code[255].flags =

264 nut->frame_code['N'].flags = FLAG_INVALID;

265 }

266

267 static void put_tt(NUTContext *nut, AVRational *time_base, AVIOContext *bc, uint64_t val)

268 {

269 val *= nut->time_base_count;

270 val += time_base - nut->time_base;

271 ff_put_v(bc, val);

272 }

273 /**

274 * Store a string as vb.

275 */

276 static void put_str(AVIOContext *bc, const char *string)

277 {

278 int len = strlen(string);

279

280 ff_put_v(bc, len);

281 avio_write(bc, string, len);

282 }

283

284 static void put_s(AVIOContext *bc, int64_t val)

285 {

286 ff_put_v(bc, 2 * FFABS(val) - (val > 0));

287 }

288

289 #ifdef TRACE

290 static inline void ff_put_v_trace(AVIOContext *bc, uint64_t v, const char *file,

291 const char *func, int line)

292 {

293 av_log(NULL, AV_LOG_DEBUG, "ff_put_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);

294

295 ff_put_v(bc, v);

296 }

297

298 static inline void put_s_trace(AVIOContext *bc, int64_t v, const char *file, const char *func, int line)

299 {

300 av_log(NULL, AV_LOG_DEBUG, "put_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line);

301

302 put_s(bc, v);

303 }

304 #define ff_put_v(bc, v) ff_put_v_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)

305 #define put_s(bc, v) put_s_trace(bc, v, __FILE__, __PRETTY_FUNCTION__, __LINE__)

306 #endif

307

308 //FIXME remove calculate_checksum

309 static void put_packet(NUTContext *nut, AVIOContext *bc, AVIOContext *dyn_bc,

310 int calculate_checksum, uint64_t startcode)

311 {

312 uint8_t *dyn_buf = NULL;

313 int dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);

314 int forw_ptr = dyn_size + 4 * calculate_checksum;

315

316 if (forw_ptr > 4096)

317 ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);

318 avio_wb64(bc, startcode);

319 ff_put_v(bc, forw_ptr);

320 if (forw_ptr > 4096)

321 avio_wl32(bc, ffio_get_checksum(bc));

322

323 if (calculate_checksum)

324 ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);

325 avio_write(bc, dyn_buf, dyn_size);

326 if (calculate_checksum)

327 avio_wl32(bc, ffio_get_checksum(bc));

328

329 av_free(dyn_buf);

330 }

331

332 static void write_mainheader(NUTContext *nut, AVIOContext *bc)

333 {

334 int i, j, tmp_pts, tmp_flags, tmp_stream, tmp_mul, tmp_size, tmp_fields,

335 tmp_head_idx;

336 int64_t tmp_match;

337

338 ff_put_v(bc, 3); /* version */

339 ff_put_v(bc, nut->avf->nb_streams);

340 ff_put_v(bc, nut->max_distance);

341 ff_put_v(bc, nut->time_base_count);

342

343 for (i = 0; i < nut->time_base_count; i++) {

344 ff_put_v(bc, nut->time_base[i].num);

345 ff_put_v(bc, nut->time_base[i].den);

346 }

347

348 tmp_pts = 0;

349 tmp_mul = 1;

350 tmp_stream = 0;

351 tmp_match = 1 - (1LL << 62);

352 tmp_head_idx = 0;

353 for (i = 0; i < 256; ) {

354 tmp_fields = 0;

355 tmp_size = 0;

356 // tmp_res=0;

357 if (tmp_pts != nut->frame_code[i].pts_delta ) tmp_fields = 1;

358 if (tmp_mul != nut->frame_code[i].size_mul ) tmp_fields = 2;

359 if (tmp_stream != nut->frame_code[i].stream_id ) tmp_fields = 3;

360 if (tmp_size != nut->frame_code[i].size_lsb ) tmp_fields = 4;

361 // if (tmp_res != nut->frame_code[i].res ) tmp_fields=5;

362 if (tmp_head_idx != nut->frame_code[i].header_idx) tmp_fields = 8;

363

364 tmp_pts = nut->frame_code[i].pts_delta;

365 tmp_flags = nut->frame_code[i].flags;

366 tmp_stream = nut->frame_code[i].stream_id;

367 tmp_mul = nut->frame_code[i].size_mul;

368 tmp_size = nut->frame_code[i].size_lsb;

369 // tmp_res = nut->frame_code[i].res;

370 tmp_head_idx = nut->frame_code[i].header_idx;

371

372 for (j = 0; i < 256; j++, i++) {

373 if (i == 'N') {

374 j--;

375 continue;

376 }

377 if (nut->frame_code[i].pts_delta != tmp_pts ||

378 nut->frame_code[i].flags != tmp_flags ||

379 nut->frame_code[i].stream_id != tmp_stream ||

380 nut->frame_code[i].size_mul != tmp_mul ||

381 nut->frame_code[i].size_lsb != tmp_size + j ||

382 // nut->frame_code[i].res != tmp_res ||

383 nut->frame_code[i].header_idx != tmp_head_idx)

384 break;

385 }

386 if (j != tmp_mul - tmp_size)

387 tmp_fields = 6;

388

389 ff_put_v(bc, tmp_flags);

390 ff_put_v(bc, tmp_fields);

391 if (tmp_fields > 0) put_s(bc, tmp_pts);

392 if (tmp_fields > 1) ff_put_v(bc, tmp_mul);

393 if (tmp_fields > 2) ff_put_v(bc, tmp_stream);

394 if (tmp_fields > 3) ff_put_v(bc, tmp_size);

395 if (tmp_fields > 4) ff_put_v(bc, 0 /*tmp_res*/);

396 if (tmp_fields > 5) ff_put_v(bc, j);

397 if (tmp_fields > 6) ff_put_v(bc, tmp_match);

398 if (tmp_fields > 7) ff_put_v(bc, tmp_head_idx);

399 }

400 ff_put_v(bc, nut->header_count - 1);

401 for (i = 1; i < nut->header_count; i++) {

402 ff_put_v(bc, nut->header_len[i]);

403 avio_write(bc, nut->header[i], nut->header_len[i]);

404 }

405 }

406

407 static int write_streamheader(AVFormatContext *avctx, AVIOContext *bc,

408 AVStream *st, int i)

409 {

410 NUTContext *nut = avctx->priv_data;

411 AVCodecContext *codec = st->codec;

412

413 ff_put_v(bc, i);

414 switch (codec->codec_type) {

415 case AVMEDIA_TYPE_VIDEO: ff_put_v(bc, 0); break;

416 case AVMEDIA_TYPE_AUDIO: ff_put_v(bc, 1); break;

417 case AVMEDIA_TYPE_SUBTITLE: ff_put_v(bc, 2); break;

418 default: ff_put_v(bc, 3); break;

419 }

420 ff_put_v(bc, 4);

421 if (codec->codec_tag) {

422 avio_wl32(bc, codec->codec_tag);

423 } else {

424 av_log(avctx, AV_LOG_ERROR, "No codec tag defined for stream %d\n", i);

425 return AVERROR(EINVAL);

426 }

427

428 ff_put_v(bc, nut->stream[i].time_base - nut->time_base);

429 ff_put_v(bc, nut->stream[i].msb_pts_shift);

430 ff_put_v(bc, nut->stream[i].max_pts_distance);

431 ff_put_v(bc, codec->has_b_frames);

432 avio_w8(bc, 0); /* flags: 0x1 - fixed_fps, 0x2 - index_present */

433

434 ff_put_v(bc, codec->extradata_size);

435 avio_write(bc, codec->extradata, codec->extradata_size);

436

437 switch (codec->codec_type) {

438 case AVMEDIA_TYPE_AUDIO:

439 ff_put_v(bc, codec->sample_rate);

440 ff_put_v(bc, 1);

441 ff_put_v(bc, codec->channels);

442 break;

443 case AVMEDIA_TYPE_VIDEO:

444 ff_put_v(bc, codec->width);

445 ff_put_v(bc, codec->height);

446

447 if (st->sample_aspect_ratio.num <= 0 ||

448 st->sample_aspect_ratio.den <= 0) {

449 ff_put_v(bc, 0);

450 ff_put_v(bc, 0);

451 } else {

452 ff_put_v(bc, st->sample_aspect_ratio.num);

453 ff_put_v(bc, st->sample_aspect_ratio.den);

454 }

455 ff_put_v(bc, 0); /* csp type -- unknown */

456 break;

457 default:

458 break;

459 }

460 return 0;

461 }

462

463 static int add_info(AVIOContext *bc, const char *type, const char *value)

464 {

465 put_str(bc, type);

466 put_s(bc, -1);

467 put_str(bc, value);

468 return 1;

469 }

470

471 static int write_globalinfo(NUTContext *nut, AVIOContext *bc)

472 {

473 AVFormatContext *s = nut->avf;

474 AVDictionaryEntry *t = NULL;

475 AVIOContext *dyn_bc;

476 uint8_t *dyn_buf = NULL;

477 int count = 0, dyn_size;

478 int ret = avio_open_dyn_buf(&dyn_bc);

479 if (ret < 0)

480 return ret;

481

482 while ((t = av_dict_get(s->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))

483 count += add_info(dyn_bc, t->key, t->value);

484

485 ff_put_v(bc, 0); //stream_if_plus1

486 ff_put_v(bc, 0); //chapter_id

487 ff_put_v(bc, 0); //timestamp_start

488 ff_put_v(bc, 0); //length

489

490 ff_put_v(bc, count);

491

492 dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);

493 avio_write(bc, dyn_buf, dyn_size);

494 av_free(dyn_buf);

495 return 0;

496 }

497

498 static int write_streaminfo(NUTContext *nut, AVIOContext *bc, int stream_id) {

499 AVFormatContext *s= nut->avf;

500 AVStream* st = s->streams[stream_id];

501 AVDictionaryEntry *t = NULL;

502 AVIOContext *dyn_bc;

503 uint8_t *dyn_buf=NULL;

504 int count=0, dyn_size, i;

505 int ret = avio_open_dyn_buf(&dyn_bc);

506 if (ret < 0)

507 return ret;

508

509 while ((t = av_dict_get(st->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))

510 count += add_info(dyn_bc, t->key, t->value);

511 for (i=0; ff_nut_dispositions[i].flag; ++i) {

512 if (st->disposition & ff_nut_dispositions[i].flag)

513 count += add_info(dyn_bc, "Disposition", ff_nut_dispositions[i].str);

514 }

515 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO) {

516 uint8_t buf[256];

517 snprintf(buf, sizeof(buf), "%d/%d", st->codec->time_base.den, st->codec->time_base.num);

518 count += add_info(dyn_bc, "r_frame_rate", buf);

519 }

520 dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);

521

522 if (count) {

523 ff_put_v(bc, stream_id + 1); //stream_id_plus1

524 ff_put_v(bc, 0); //chapter_id

525 ff_put_v(bc, 0); //timestamp_start

526 ff_put_v(bc, 0); //length

527

528 ff_put_v(bc, count);

529

530 avio_write(bc, dyn_buf, dyn_size);

531 }

532

533 av_free(dyn_buf);

534 return count;

535 }

536

537 static int write_chapter(NUTContext *nut, AVIOContext *bc, int id)

538 {

539 AVIOContext *dyn_bc;

540 uint8_t *dyn_buf = NULL;

541 AVDictionaryEntry *t = NULL;

542 AVChapter *ch = nut->avf->chapters[id];

543 int ret, dyn_size, count = 0;

544

545 ret = avio_open_dyn_buf(&dyn_bc);

546 if (ret < 0)

547 return ret;

548

549 ff_put_v(bc, 0); // stream_id_plus1

550 put_s(bc, id + 1); // chapter_id

551 put_tt(nut, nut->chapter[id].time_base, bc, ch->start); // chapter_start

552 ff_put_v(bc, ch->end - ch->start); // chapter_len

553

554 while ((t = av_dict_get(ch->metadata, "", t, AV_DICT_IGNORE_SUFFIX)))

555 count += add_info(dyn_bc, t->key, t->value);

556

557 ff_put_v(bc, count);

558

559 dyn_size = avio_close_dyn_buf(dyn_bc, &dyn_buf);

560 avio_write(bc, dyn_buf, dyn_size);

561 av_freep(&dyn_buf);

562 return 0;

563 }

564

565 static int write_index(NUTContext *nut, AVIOContext *bc) {

566 int i;

567 Syncpoint dummy= { .pos= 0 };

568 Syncpoint *next_node[2] = { NULL };

569 int64_t startpos = avio_tell(bc);

570 int64_t payload_size;

571

572 put_tt(nut, nut->max_pts_tb, bc, nut->max_pts);

573

574 ff_put_v(bc, nut->sp_count);

575

576 for (i=0; i<nut->sp_count; i++) {

577 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp, (void**)next_node);

578 ff_put_v(bc, (next_node[1]->pos >> 4) - (dummy.pos>>4));

579 dummy.pos = next_node[1]->pos;

580 }

581

582 for (i=0; i<nut->avf->nb_streams; i++) {

583 StreamContext *nus= &nut->stream[i];

584 int64_t last_pts= -1;

585 int j, k;

586 for (j=0; j<nut->sp_count; j++) {

587 int flag = (nus->keyframe_pts[j] != AV_NOPTS_VALUE) ^ (j+1 == nut->sp_count);

588 int n = 0;

589 for (; j<nut->sp_count && (nus->keyframe_pts[j] != AV_NOPTS_VALUE) == flag; j++)

590 n++;

591

592 ff_put_v(bc, 1 + 2*flag + 4*n);

593 for (k= j - n; k<=j && k<nut->sp_count; k++) {

594 if (nus->keyframe_pts[k] == AV_NOPTS_VALUE)

595 continue;

596 av_assert0(nus->keyframe_pts[k] > last_pts);

597 ff_put_v(bc, nus->keyframe_pts[k] - last_pts);

598 last_pts = nus->keyframe_pts[k];

599 }

600 }

601 }

602

603 payload_size = avio_tell(bc) - startpos + 8 + 4;

604

605 avio_wb64(bc, 8 + payload_size + av_log2(payload_size) / 7 + 1 + 4*(payload_size > 4096));

606

607 return 0;

608 }

609

610 static int write_headers(AVFormatContext *avctx, AVIOContext *bc)

611 {

612 NUTContext *nut = avctx->priv_data;

613 AVIOContext *dyn_bc;

614 int i, ret;

615

616 ff_metadata_conv_ctx(avctx, ff_nut_metadata_conv, NULL);

617

618 ret = avio_open_dyn_buf(&dyn_bc);

619 if (ret < 0)

620 return ret;

621 write_mainheader(nut, dyn_bc);

622 put_packet(nut, bc, dyn_bc, 1, MAIN_STARTCODE);

623

624 for (i = 0; i < nut->avf->nb_streams; i++) {

625 ret = avio_open_dyn_buf(&dyn_bc);

626 if (ret < 0)

627 return ret;

628 ret = write_streamheader(avctx, dyn_bc, nut->avf->streams[i], i);

629 if (ret < 0)

630 return ret;

631 put_packet(nut, bc, dyn_bc, 1, STREAM_STARTCODE);

632 }

633

634 ret = avio_open_dyn_buf(&dyn_bc);

635 if (ret < 0)

636 return ret;

637 write_globalinfo(nut, dyn_bc);

638 put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);

639

640 for (i = 0; i < nut->avf->nb_streams; i++) {

641 ret = avio_open_dyn_buf(&dyn_bc);

642 if (ret < 0)

643 return ret;

644 ret = write_streaminfo(nut, dyn_bc, i);

645 if (ret < 0)

646 return ret;

647 if (ret > 0)

648 put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);

649 else {

650 uint8_t *buf;

651 avio_close_dyn_buf(dyn_bc, &buf);

652 av_free(buf);

653 }

654 }

655

656 for (i = 0; i < nut->avf->nb_chapters; i++) {

657 ret = avio_open_dyn_buf(&dyn_bc);

658 if (ret < 0)

659 return ret;

660 ret = write_chapter(nut, dyn_bc, i);

661 if (ret < 0) {

662 uint8_t *buf;

663 avio_close_dyn_buf(dyn_bc, &buf);

664 av_freep(&buf);

665 return ret;

666 }

667 put_packet(nut, bc, dyn_bc, 1, INFO_STARTCODE);

668 }

669

670 nut->last_syncpoint_pos = INT_MIN;

671 nut->header_count++;

672 return 0;

673 }

674

675 static int nut_write_header(AVFormatContext *s)

676 {

677 NUTContext *nut = s->priv_data;

678 AVIOContext *bc = s->pb;

679 int i, j, ret;

680

681 nut->avf = s;

682

683 nut->stream = av_mallocz(sizeof(StreamContext ) * s->nb_streams);

684 nut->chapter = av_mallocz(sizeof(ChapterContext) * s->nb_chapters);

685 nut->time_base= av_mallocz(sizeof(AVRational ) *(s->nb_streams +

686 s->nb_chapters));

687 if (!nut->stream || !nut->chapter || !nut->time_base) {

688 av_freep(&nut->stream);

689 av_freep(&nut->chapter);

690 av_freep(&nut->time_base);

691 return AVERROR(ENOMEM);

692 }

693

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

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

696 int ssize;

697 AVRational time_base;

698 ff_parse_specific_params(st->codec, &time_base.den, &ssize, &time_base.num);

699

700 if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO && st->codec->sample_rate) {

701 time_base = (AVRational) {1, st->codec->sample_rate};

702 } else {

703 time_base = ff_choose_timebase(s, st, 48000);

704 }

705

706 avpriv_set_pts_info(st, 64, time_base.num, time_base.den);

707

708 for (j = 0; j < nut->time_base_count; j++)

709 if (!memcmp(&time_base, &nut->time_base[j], sizeof(AVRational))) {

710 break;

711 }

712 nut->time_base[j] = time_base;

713 nut->stream[i].time_base = &nut->time_base[j];

714 if (j == nut->time_base_count)

715 nut->time_base_count++;

716

717 if (INT64_C(1000) * time_base.num >= time_base.den)

718 nut->stream[i].msb_pts_shift = 7;

719 else

720 nut->stream[i].msb_pts_shift = 14;

721 nut->stream[i].max_pts_distance =

722 FFMAX(time_base.den, time_base.num) / time_base.num;

723 }

724

725 for (i = 0; i < s->nb_chapters; i++) {

726 AVChapter *ch = s->chapters[i];

727

728 for (j = 0; j < nut->time_base_count; j++)

729 if (!memcmp(&ch->time_base, &nut->time_base[j], sizeof(AVRational)))

730 break;

731

732 nut->time_base[j] = ch->time_base;

733 nut->chapter[i].time_base = &nut->time_base[j];

734 if (j == nut->time_base_count)

735 nut->time_base_count++;

736 }

737

738 nut->max_distance = MAX_DISTANCE;

739 build_elision_headers(s);

740 build_frame_code(s);

741 av_assert0(nut->frame_code['N'].flags == FLAG_INVALID);

742

743 avio_write(bc, ID_STRING, strlen(ID_STRING));

744 avio_w8(bc, 0);

745

746 if ((ret = write_headers(s, bc)) < 0)

747 return ret;

748

749 if (s->avoid_negative_ts < 0)

750 s->avoid_negative_ts = 1;

751

752 avio_flush(bc);

753

754 return 0;

755 }

756

757 static int get_needed_flags(NUTContext *nut, StreamContext *nus, FrameCode *fc,

758 AVPacket *pkt)

759 {

760 int flags = 0;

761

762 if (pkt->flags & AV_PKT_FLAG_KEY)

763 flags |= FLAG_KEY;

764 if (pkt->stream_index != fc->stream_id)

765 flags |= FLAG_STREAM_ID;

766 if (pkt->size / fc->size_mul)

767 flags |= FLAG_SIZE_MSB;

768 if (pkt->pts - nus->last_pts != fc->pts_delta)

769 flags |= FLAG_CODED_PTS;

770 if (pkt->size > 2 * nut->max_distance)

771 flags |= FLAG_CHECKSUM;

772 if (FFABS(pkt->pts - nus->last_pts) > nus->max_pts_distance)

773 flags |= FLAG_CHECKSUM;

774 if (pkt->size < nut->header_len[fc->header_idx] ||

775 (pkt->size > 4096 && fc->header_idx) ||

776 memcmp(pkt->data, nut->header[fc->header_idx],

777 nut->header_len[fc->header_idx]))

778 flags |= FLAG_HEADER_IDX;

779

780 return flags | (fc->flags & FLAG_CODED);

781 }

782

783 static int find_best_header_idx(NUTContext *nut, AVPacket *pkt)

784 {

785 int i;

786 int best_i = 0;

787 int best_len = 0;

788

789 if (pkt->size > 4096)

790 return 0;

791

792 for (i = 1; i < nut->header_count; i++)

793 if (pkt->size >= nut->header_len[i]

794 && nut->header_len[i] > best_len

795 && !memcmp(pkt->data, nut->header[i], nut->header_len[i])) {

796 best_i = i;

797 best_len = nut->header_len[i];

798 }

799 return best_i;

800 }

801

802 static int nut_write_packet(AVFormatContext *s, AVPacket *pkt)

803 {

804 NUTContext *nut = s->priv_data;

805 StreamContext *nus = &nut->stream[pkt->stream_index];

806 AVIOContext *bc = s->pb, *dyn_bc;

807 FrameCode *fc;

808 int64_t coded_pts;

809 int best_length, frame_code, flags, needed_flags, i, header_idx;

810 int best_header_idx;

811 int key_frame = !!(pkt->flags & AV_PKT_FLAG_KEY);

812 int store_sp = 0;

813 int ret;

814

815 if (pkt->pts < 0) {

816 av_log(s, AV_LOG_ERROR,

817 "Negative pts not supported stream %d, pts %"PRId64"\n",

818 pkt->stream_index, pkt->pts);

819 return AVERROR(EINVAL);

820 }

821

822 if (1LL << (20 + 3 * nut->header_count) <= avio_tell(bc))

823 write_headers(s, bc);

824

825 if (key_frame && !(nus->last_flags & FLAG_KEY))

826 store_sp = 1;

827

828 if (pkt->size + 30 /*FIXME check*/ + avio_tell(bc) >= nut->last_syncpoint_pos + nut->max_distance)

829 store_sp = 1;

830

831 //FIXME: Ensure store_sp is 1 in the first place.

832

833 if (store_sp) {

834 Syncpoint *sp, dummy = { .pos = INT64_MAX };

835

836 ff_nut_reset_ts(nut, *nus->time_base, pkt->dts);

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

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

839 int64_t dts_tb = av_rescale_rnd(pkt->dts,

840 nus->time_base->num * (int64_t)nut->stream[i].time_base->den,

841 nus->time_base->den * (int64_t)nut->stream[i].time_base->num,

842 AV_ROUND_DOWN);

843 int index = av_index_search_timestamp(st, dts_tb,

844 AVSEEK_FLAG_BACKWARD);

845 if (index >= 0)

846 dummy.pos = FFMIN(dummy.pos, st->index_entries[index].pos);

847 }

848 if (dummy.pos == INT64_MAX)

849 dummy.pos = 0;

850 sp = av_tree_find(nut->syncpoints, &dummy, (void *)ff_nut_sp_pos_cmp,

851 NULL);

852

853 nut->last_syncpoint_pos = avio_tell(bc);

854 ret = avio_open_dyn_buf(&dyn_bc);

855 if (ret < 0)

856 return ret;

857 put_tt(nut, nus->time_base, dyn_bc, pkt->dts);

858 ff_put_v(dyn_bc, sp ? (nut->last_syncpoint_pos - sp->pos) >> 4 : 0);

859 put_packet(nut, bc, dyn_bc, 1, SYNCPOINT_STARTCODE);

860

861 ff_nut_add_sp(nut, nut->last_syncpoint_pos, 0 /*unused*/, pkt->dts);

862

863 if ((1ll<<60) % nut->sp_count == 0)

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

865 int j;

866 StreamContext *nus = &nut->stream[i];

867 nus->keyframe_pts = av_realloc(nus->keyframe_pts, 2*nut->sp_count*sizeof(*nus->keyframe_pts));

868 if (!nus->keyframe_pts)

869 return AVERROR(ENOMEM);

870 for (j=nut->sp_count == 1 ? 0 : nut->sp_count; j<2*nut->sp_count; j++)

871 nus->keyframe_pts[j] = AV_NOPTS_VALUE;

872 }

873 }

874 av_assert0(nus->last_pts != AV_NOPTS_VALUE);

875

876 coded_pts = pkt->pts & ((1 << nus->msb_pts_shift) - 1);

877 if (ff_lsb2full(nus, coded_pts) != pkt->pts)

878 coded_pts = pkt->pts + (1 << nus->msb_pts_shift);

879

880 best_header_idx = find_best_header_idx(nut, pkt);

881

882 best_length = INT_MAX;

883 frame_code = -1;

884 for (i = 0; i < 256; i++) {

885 int length = 0;

886 FrameCode *fc = &nut->frame_code[i];

887 int flags = fc->flags;

888

889 if (flags & FLAG_INVALID)

890 continue;

891 needed_flags = get_needed_flags(nut, nus, fc, pkt);

892

893 if (flags & FLAG_CODED) {

894 length++;

895 flags = needed_flags;

896 }

897

898 if ((flags & needed_flags) != needed_flags)

899 continue;

900

901 if ((flags ^ needed_flags) & FLAG_KEY)

902 continue;

903

904 if (flags & FLAG_STREAM_ID)

905 length += ff_get_v_length(pkt->stream_index);

906

907 if (pkt->size % fc->size_mul != fc->size_lsb)

908 continue;

909 if (flags & FLAG_SIZE_MSB)

910 length += ff_get_v_length(pkt->size / fc->size_mul);

911

912 if (flags & FLAG_CHECKSUM)

913 length += 4;

914

915 if (flags & FLAG_CODED_PTS)

916 length += ff_get_v_length(coded_pts);

917

918 if ( (flags & FLAG_CODED)

919 && nut->header_len[best_header_idx] > nut->header_len[fc->header_idx] + 1) {

920 flags |= FLAG_HEADER_IDX;

921 }

922

923 if (flags & FLAG_HEADER_IDX) {

924 length += 1 - nut->header_len[best_header_idx];

925 } else {

926 length -= nut->header_len[fc->header_idx];

927 }

928

929 length *= 4;

930 length += !(flags & FLAG_CODED_PTS);

931 length += !(flags & FLAG_CHECKSUM);

932

933 if (length < best_length) {

934 best_length = length;

935 frame_code = i;

936 }

937 }

938 av_assert0(frame_code != -1);

939 fc = &nut->frame_code[frame_code];

940 flags = fc->flags;

941 needed_flags = get_needed_flags(nut, nus, fc, pkt);

942 header_idx = fc->header_idx;

943

944 ffio_init_checksum(bc, ff_crc04C11DB7_update, 0);

945 avio_w8(bc, frame_code);

946 if (flags & FLAG_CODED) {

947 ff_put_v(bc, (flags ^ needed_flags) & ~(FLAG_CODED));

948 flags = needed_flags;

949 }

950 if (flags & FLAG_STREAM_ID) ff_put_v(bc, pkt->stream_index);

951 if (flags & FLAG_CODED_PTS) ff_put_v(bc, coded_pts);

952 if (flags & FLAG_SIZE_MSB ) ff_put_v(bc, pkt->size / fc->size_mul);

953 if (flags & FLAG_HEADER_IDX) ff_put_v(bc, header_idx = best_header_idx);

954

955 if (flags & FLAG_CHECKSUM) avio_wl32(bc, ffio_get_checksum(bc));

956 else ffio_get_checksum(bc);

957

958 avio_write(bc, pkt->data + nut->header_len[header_idx], pkt->size - nut->header_len[header_idx]);

959 nus->last_flags = flags;

960 nus->last_pts = pkt->pts;

961

962 //FIXME just store one per syncpoint

963 if (flags & FLAG_KEY) {

964 av_add_index_entry(

965 s->streams[pkt->stream_index],

966 nut->last_syncpoint_pos,

967 pkt->pts,

968 0,

969 0,

970 AVINDEX_KEYFRAME);

971 if (nus->keyframe_pts && nus->keyframe_pts[nut->sp_count] == AV_NOPTS_VALUE)

972 nus->keyframe_pts[nut->sp_count] = pkt->pts;

973 }

974

975 if (!nut->max_pts_tb || av_compare_ts(nut->max_pts, *nut->max_pts_tb, pkt->pts, *nus->time_base) < 0) {

976 nut->max_pts = pkt->pts;

977 nut->max_pts_tb = nus->time_base;

978 }

979

980 return 0;

981 }

982

983 static int nut_write_trailer(AVFormatContext *s)

984 {

985 NUTContext *nut = s->priv_data;

986 AVIOContext *bc = s->pb, *dyn_bc;

987 int i, ret;

988

989 while (nut->header_count < 3)

990 write_headers(s, bc);

991

992 ret = avio_open_dyn_buf(&dyn_bc);

993 if (ret >= 0) {

994 write_index(nut, dyn_bc);

995 put_packet(nut, bc, dyn_bc, 1, INDEX_STARTCODE);

996 }

997

998 ff_nut_free_sp(nut);

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

1000 av_freep(&nut->stream[i].keyframe_pts);

1001

1002 av_freep(&nut->stream);

1003 av_freep(&nut->chapter);

1004 av_freep(&nut->time_base);

1005

1006 return 0;

1007 }

1008

1009 AVOutputFormat ff_nut_muxer = {

1010 .name = "nut",

1011 .long_name = NULL_IF_CONFIG_SMALL("NUT"),

1012 .mime_type = "video/x-nut",

1013 .extensions = "nut",

1014 .priv_data_size = sizeof(NUTContext),

1015 .audio_codec = CONFIG_LIBVORBIS ? AV_CODEC_ID_VORBIS :

1016 CONFIG_LIBMP3LAME ? AV_CODEC_ID_MP3 : AV_CODEC_ID_MP2,

1017 .video_codec = AV_CODEC_ID_MPEG4,

1018 .write_header = nut_write_header,

1019 .write_packet = nut_write_packet,

1020 .write_trailer = nut_write_trailer,

1021 .flags = AVFMT_GLOBALHEADER | AVFMT_VARIABLE_FPS,

1022 .codec_tag = ff_nut_codec_tags,

1023 };

Generated on Sat May 25 2013 03:58:48 for FFmpeg by doxygen 1.8.2