1/* 2 * General DV muxer/demuxer 3 * Copyright (c) 2003 Roman Shaposhnik 4 * 5 * Many thanks to Dan Dennedy <dan@dennedy.org> for providing wealth 6 * of DV technical info. 7 * 8 * Raw DV format 9 * Copyright (c) 2002 Fabrice Bellard 10 * 11 * 50 Mbps (DVCPRO50) and 100 Mbps (DVCPRO HD) support 12 * Copyright (c) 2006 Daniel Maas <dmaas@maasdigital.com> 13 * Funded by BBC Research & Development 14 * 15 * This file is part of Libav. 16 * 17 * Libav is free software; you can redistribute it and/or 18 * modify it under the terms of the GNU Lesser General Public 19 * License as published by the Free Software Foundation; either 20 * version 2.1 of the License, or (at your option) any later version. 21 * 22 * Libav is distributed in the hope that it will be useful, 23 * but WITHOUT ANY WARRANTY; without even the implied warranty of 24 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 25 * Lesser General Public License for more details. 26 * 27 * You should have received a copy of the GNU Lesser General Public 28 * License along with Libav; if not, write to the Free Software 29 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 30 */ 31#include <time.h> 32#include "avformat.h" 33#include "internal.h" 34#include "libavcodec/dvdata.h" 35#include "libavutil/intreadwrite.h" 36#include "libavutil/mathematics.h" 37#include "dv.h" 38 39struct DVDemuxContext { 40 const DVprofile* sys; /* Current DV profile. E.g.: 525/60, 625/50 */ 41 AVFormatContext* fctx; 42 AVStream* vst; 43 AVStream* ast[4]; 44 AVPacket audio_pkt[4]; 45 uint8_t audio_buf[4][8192]; 46 int ach; 47 int frames; 48 uint64_t abytes; 49}; 50 51static inline uint16_t dv_audio_12to16(uint16_t sample) 52{ 53 uint16_t shift, result; 54 55 sample = (sample < 0x800) ? sample : sample | 0xf000; 56 shift = (sample & 0xf00) >> 8; 57 58 if (shift < 0x2 || shift > 0xd) { 59 result = sample; 60 } else if (shift < 0x8) { 61 shift--; 62 result = (sample - (256 * shift)) << shift; 63 } else { 64 shift = 0xe - shift; 65 result = ((sample + ((256 * shift) + 1)) << shift) - 1; 66 } 67 68 return result; 69} 70 71/* 72 * This is the dumbest implementation of all -- it simply looks at 73 * a fixed offset and if pack isn't there -- fails. We might want 74 * to have a fallback mechanism for complete search of missing packs. 75 */ 76static const uint8_t* dv_extract_pack(uint8_t* frame, enum dv_pack_type t) 77{ 78 int offs; 79 80 switch (t) { 81 case dv_audio_source: 82 offs = (80*6 + 80*16*3 + 3); 83 break; 84 case dv_audio_control: 85 offs = (80*6 + 80*16*4 + 3); 86 break; 87 case dv_video_control: 88 offs = (80*5 + 48 + 5); 89 break; 90 default: 91 return NULL; 92 } 93 94 return frame[offs] == t ? &frame[offs] : NULL; 95} 96 97/* 98 * There's a couple of assumptions being made here: 99 * 1. By default we silence erroneous (0x8000/16bit 0x800/12bit) audio samples. 100 * We can pass them upwards when libavcodec will be ready to deal with them. 101 * 2. We don't do software emphasis. 102 * 3. Audio is always returned as 16bit linear samples: 12bit nonlinear samples 103 * are converted into 16bit linear ones. 104 */ 105static int dv_extract_audio(uint8_t* frame, uint8_t* ppcm[4], 106 const DVprofile *sys) 107{ 108 int size, chan, i, j, d, of, smpls, freq, quant, half_ch; 109 uint16_t lc, rc; 110 const uint8_t* as_pack; 111 uint8_t *pcm, ipcm; 112 113 as_pack = dv_extract_pack(frame, dv_audio_source); 114 if (!as_pack) /* No audio ? */ 115 return 0; 116 117 smpls = as_pack[1] & 0x3f; /* samples in this frame - min. samples */ 118 freq = (as_pack[4] >> 3) & 0x07; /* 0 - 48kHz, 1 - 44,1kHz, 2 - 32kHz */ 119 quant = as_pack[4] & 0x07; /* 0 - 16bit linear, 1 - 12bit nonlinear */ 120 121 if (quant > 1) 122 return -1; /* unsupported quantization */ 123 124 if (freq >= FF_ARRAY_ELEMS(dv_audio_frequency)) 125 return AVERROR_INVALIDDATA; 126 127 size = (sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */ 128 half_ch = sys->difseg_size / 2; 129 130 /* We work with 720p frames split in half, thus even frames have 131 * channels 0,1 and odd 2,3. */ 132 ipcm = (sys->height == 720 && !(frame[1] & 0x0C)) ? 2 : 0; 133 134 /* for each DIF channel */ 135 for (chan = 0; chan < sys->n_difchan; chan++) { 136 /* next stereo channel (50Mbps and 100Mbps only) */ 137 pcm = ppcm[ipcm++]; 138 if (!pcm) 139 break; 140 141 /* for each DIF segment */ 142 for (i = 0; i < sys->difseg_size; i++) { 143 frame += 6 * 80; /* skip DIF segment header */ 144 if (quant == 1 && i == half_ch) { 145 /* next stereo channel (12bit mode only) */ 146 pcm = ppcm[ipcm++]; 147 if (!pcm) 148 break; 149 } 150 151 /* for each AV sequence */ 152 for (j = 0; j < 9; j++) { 153 for (d = 8; d < 80; d += 2) { 154 if (quant == 0) { /* 16bit quantization */ 155 of = sys->audio_shuffle[i][j] + (d - 8) / 2 * sys->audio_stride; 156 if (of*2 >= size) 157 continue; 158 159 pcm[of*2] = frame[d+1]; // FIXME: maybe we have to admit 160 pcm[of*2+1] = frame[d]; // that DV is a big-endian PCM 161 if (pcm[of*2+1] == 0x80 && pcm[of*2] == 0x00) 162 pcm[of*2+1] = 0; 163 } else { /* 12bit quantization */ 164 lc = ((uint16_t)frame[d] << 4) | 165 ((uint16_t)frame[d+2] >> 4); 166 rc = ((uint16_t)frame[d+1] << 4) | 167 ((uint16_t)frame[d+2] & 0x0f); 168 lc = (lc == 0x800 ? 0 : dv_audio_12to16(lc)); 169 rc = (rc == 0x800 ? 0 : dv_audio_12to16(rc)); 170 171 of = sys->audio_shuffle[i%half_ch][j] + (d - 8) / 3 * sys->audio_stride; 172 if (of*2 >= size) 173 continue; 174 175 pcm[of*2] = lc & 0xff; // FIXME: maybe we have to admit 176 pcm[of*2+1] = lc >> 8; // that DV is a big-endian PCM 177 of = sys->audio_shuffle[i%half_ch+half_ch][j] + 178 (d - 8) / 3 * sys->audio_stride; 179 pcm[of*2] = rc & 0xff; // FIXME: maybe we have to admit 180 pcm[of*2+1] = rc >> 8; // that DV is a big-endian PCM 181 ++d; 182 } 183 } 184 185 frame += 16 * 80; /* 15 Video DIFs + 1 Audio DIF */ 186 } 187 } 188 } 189 190 return size; 191} 192 193static int dv_extract_audio_info(DVDemuxContext* c, uint8_t* frame) 194{ 195 const uint8_t* as_pack; 196 int freq, stype, smpls, quant, i, ach; 197 198 as_pack = dv_extract_pack(frame, dv_audio_source); 199 if (!as_pack || !c->sys) { /* No audio ? */ 200 c->ach = 0; 201 return 0; 202 } 203 204 smpls = as_pack[1] & 0x3f; /* samples in this frame - min. samples */ 205 freq = (as_pack[4] >> 3) & 0x07; /* 0 - 48kHz, 1 - 44,1kHz, 2 - 32kHz */ 206 stype = (as_pack[3] & 0x1f); /* 0 - 2CH, 2 - 4CH, 3 - 8CH */ 207 quant = as_pack[4] & 0x07; /* 0 - 16bit linear, 1 - 12bit nonlinear */ 208 209 if (freq >= FF_ARRAY_ELEMS(dv_audio_frequency)) { 210 av_log(c->fctx, AV_LOG_ERROR, 211 "Unrecognized audio sample rate index (%d)\n", freq); 212 return 0; 213 } 214 215 if (stype > 3) { 216 av_log(c->fctx, AV_LOG_ERROR, "stype %d is invalid\n", stype); 217 c->ach = 0; 218 return 0; 219 } 220 221 /* note: ach counts PAIRS of channels (i.e. stereo channels) */ 222 ach = ((int[4]){ 1, 0, 2, 4})[stype]; 223 if (ach == 1 && quant && freq == 2) 224 ach = 2; 225 226 /* Dynamic handling of the audio streams in DV */ 227 for (i = 0; i < ach; i++) { 228 if (!c->ast[i]) { 229 c->ast[i] = avformat_new_stream(c->fctx, NULL); 230 if (!c->ast[i]) 231 break; 232 avpriv_set_pts_info(c->ast[i], 64, 1, 30000); 233 c->ast[i]->codec->codec_type = AVMEDIA_TYPE_AUDIO; 234 c->ast[i]->codec->codec_id = CODEC_ID_PCM_S16LE; 235 236 av_init_packet(&c->audio_pkt[i]); 237 c->audio_pkt[i].size = 0; 238 c->audio_pkt[i].data = c->audio_buf[i]; 239 c->audio_pkt[i].stream_index = c->ast[i]->index; 240 c->audio_pkt[i].flags |= AV_PKT_FLAG_KEY; 241 } 242 c->ast[i]->codec->sample_rate = dv_audio_frequency[freq]; 243 c->ast[i]->codec->channels = 2; 244 c->ast[i]->codec->bit_rate = 2 * dv_audio_frequency[freq] * 16; 245 c->ast[i]->start_time = 0; 246 } 247 c->ach = i; 248 249 return (c->sys->audio_min_samples[freq] + smpls) * 4; /* 2ch, 2bytes */; 250} 251 252static int dv_extract_video_info(DVDemuxContext *c, uint8_t* frame) 253{ 254 const uint8_t* vsc_pack; 255 AVCodecContext* avctx; 256 int apt, is16_9; 257 int size = 0; 258 259 if (c->sys) { 260 avctx = c->vst->codec; 261 262 avpriv_set_pts_info(c->vst, 64, c->sys->time_base.num, 263 c->sys->time_base.den); 264 avctx->time_base= c->sys->time_base; 265 if (!avctx->width){ 266 avctx->width = c->sys->width; 267 avctx->height = c->sys->height; 268 } 269 avctx->pix_fmt = c->sys->pix_fmt; 270 271 /* finding out SAR is a little bit messy */ 272 vsc_pack = dv_extract_pack(frame, dv_video_control); 273 apt = frame[4] & 0x07; 274 is16_9 = (vsc_pack && ((vsc_pack[2] & 0x07) == 0x02 || 275 (!apt && (vsc_pack[2] & 0x07) == 0x07))); 276 c->vst->sample_aspect_ratio = c->sys->sar[is16_9]; 277 avctx->bit_rate = av_rescale_q(c->sys->frame_size, (AVRational){8,1}, 278 c->sys->time_base); 279 size = c->sys->frame_size; 280 } 281 return size; 282} 283 284/* 285 * The following 3 functions constitute our interface to the world 286 */ 287 288DVDemuxContext* avpriv_dv_init_demux(AVFormatContext *s) 289{ 290 DVDemuxContext *c; 291 292 c = av_mallocz(sizeof(DVDemuxContext)); 293 if (!c) 294 return NULL; 295 296 c->vst = avformat_new_stream(s, NULL); 297 if (!c->vst) { 298 av_free(c); 299 return NULL; 300 } 301 302 c->sys = NULL; 303 c->fctx = s; 304 memset(c->ast, 0, sizeof(c->ast)); 305 c->ach = 0; 306 c->frames = 0; 307 c->abytes = 0; 308 309 c->vst->codec->codec_type = AVMEDIA_TYPE_VIDEO; 310 c->vst->codec->codec_id = CODEC_ID_DVVIDEO; 311 c->vst->codec->bit_rate = 25000000; 312 c->vst->start_time = 0; 313 314 return c; 315} 316 317int avpriv_dv_get_packet(DVDemuxContext *c, AVPacket *pkt) 318{ 319 int size = -1; 320 int i; 321 322 for (i = 0; i < c->ach; i++) { 323 if (c->ast[i] && c->audio_pkt[i].size) { 324 *pkt = c->audio_pkt[i]; 325 c->audio_pkt[i].size = 0; 326 size = pkt->size; 327 break; 328 } 329 } 330 331 return size; 332} 333 334int avpriv_dv_produce_packet(DVDemuxContext *c, AVPacket *pkt, 335 uint8_t* buf, int buf_size) 336{ 337 int size, i; 338 uint8_t *ppcm[4] = {0}; 339 340 if (buf_size < DV_PROFILE_BYTES || 341 !(c->sys = avpriv_dv_frame_profile(c->sys, buf, buf_size)) || 342 buf_size < c->sys->frame_size) { 343 return -1; /* Broken frame, or not enough data */ 344 } 345 346 /* Queueing audio packet */ 347 /* FIXME: in case of no audio/bad audio we have to do something */ 348 size = dv_extract_audio_info(c, buf); 349 for (i = 0; i < c->ach; i++) { 350 c->audio_pkt[i].size = size; 351 c->audio_pkt[i].pts = c->abytes * 30000*8 / c->ast[i]->codec->bit_rate; 352 ppcm[i] = c->audio_buf[i]; 353 } 354 if (c->ach) 355 dv_extract_audio(buf, ppcm, c->sys); 356 357 /* We work with 720p frames split in half, thus even frames have 358 * channels 0,1 and odd 2,3. */ 359 if (c->sys->height == 720) { 360 if (buf[1] & 0x0C) { 361 c->audio_pkt[2].size = c->audio_pkt[3].size = 0; 362 } else { 363 c->audio_pkt[0].size = c->audio_pkt[1].size = 0; 364 c->abytes += size; 365 } 366 } else { 367 c->abytes += size; 368 } 369 370 /* Now it's time to return video packet */ 371 size = dv_extract_video_info(c, buf); 372 av_init_packet(pkt); 373 pkt->data = buf; 374 pkt->size = size; 375 pkt->flags |= AV_PKT_FLAG_KEY; 376 pkt->stream_index = c->vst->id; 377 pkt->pts = c->frames; 378 379 c->frames++; 380 381 return size; 382} 383 384static int64_t dv_frame_offset(AVFormatContext *s, DVDemuxContext *c, 385 int64_t timestamp, int flags) 386{ 387 // FIXME: sys may be wrong if last dv_read_packet() failed (buffer is junk) 388 const DVprofile* sys = avpriv_dv_codec_profile(c->vst->codec); 389 int64_t offset; 390 int64_t size = avio_size(s->pb) - s->data_offset; 391 int64_t max_offset = ((size-1) / sys->frame_size) * sys->frame_size; 392 393 offset = sys->frame_size * timestamp; 394 395 if (size >= 0 && offset > max_offset) offset = max_offset; 396 else if (offset < 0) offset = 0; 397 398 return offset + s->data_offset; 399} 400 401void dv_offset_reset(DVDemuxContext *c, int64_t frame_offset) 402{ 403 c->frames= frame_offset; 404 if (c->ach) 405 c->abytes= av_rescale_q(c->frames, c->sys->time_base, 406 (AVRational){8, c->ast[0]->codec->bit_rate}); 407 c->audio_pkt[0].size = c->audio_pkt[1].size = 0; 408 c->audio_pkt[2].size = c->audio_pkt[3].size = 0; 409} 410 411/************************************************************ 412 * Implementation of the easiest DV storage of all -- raw DV. 413 ************************************************************/ 414 415typedef struct RawDVContext { 416 DVDemuxContext* dv_demux; 417 uint8_t buf[DV_MAX_FRAME_SIZE]; 418} RawDVContext; 419 420static int dv_read_header(AVFormatContext *s, 421 AVFormatParameters *ap) 422{ 423 unsigned state, marker_pos = 0; 424 RawDVContext *c = s->priv_data; 425 426 c->dv_demux = avpriv_dv_init_demux(s); 427 if (!c->dv_demux) 428 return -1; 429 430 state = avio_rb32(s->pb); 431 while ((state & 0xffffff7f) != 0x1f07003f) { 432 if (s->pb->eof_reached) { 433 av_log(s, AV_LOG_ERROR, "Cannot find DV header.\n"); 434 return -1; 435 } 436 if (state == 0x003f0700 || state == 0xff3f0700) 437 marker_pos = avio_tell(s->pb); 438 if (state == 0xff3f0701 && avio_tell(s->pb) - marker_pos == 80) { 439 avio_seek(s->pb, -163, SEEK_CUR); 440 state = avio_rb32(s->pb); 441 break; 442 } 443 state = (state << 8) | avio_r8(s->pb); 444 } 445 AV_WB32(c->buf, state); 446 447 if (avio_read(s->pb, c->buf + 4, DV_PROFILE_BYTES - 4) <= 0 || 448 avio_seek(s->pb, -DV_PROFILE_BYTES, SEEK_CUR) < 0) 449 return AVERROR(EIO); 450 451 c->dv_demux->sys = avpriv_dv_frame_profile(c->dv_demux->sys, c->buf, DV_PROFILE_BYTES); 452 if (!c->dv_demux->sys) { 453 av_log(s, AV_LOG_ERROR, "Can't determine profile of DV input stream.\n"); 454 return -1; 455 } 456 457 s->bit_rate = av_rescale_q(c->dv_demux->sys->frame_size, (AVRational){8,1}, 458 c->dv_demux->sys->time_base); 459 460 return 0; 461} 462 463 464static int dv_read_packet(AVFormatContext *s, AVPacket *pkt) 465{ 466 int size; 467 RawDVContext *c = s->priv_data; 468 469 size = avpriv_dv_get_packet(c->dv_demux, pkt); 470 471 if (size < 0) { 472 if (!c->dv_demux->sys) 473 return AVERROR(EIO); 474 size = c->dv_demux->sys->frame_size; 475 if (avio_read(s->pb, c->buf, size) <= 0) 476 return AVERROR(EIO); 477 478 size = avpriv_dv_produce_packet(c->dv_demux, pkt, c->buf, size); 479 } 480 481 return size; 482} 483 484static int dv_read_seek(AVFormatContext *s, int stream_index, 485 int64_t timestamp, int flags) 486{ 487 RawDVContext *r = s->priv_data; 488 DVDemuxContext *c = r->dv_demux; 489 int64_t offset = dv_frame_offset(s, c, timestamp, flags); 490 491 dv_offset_reset(c, offset / c->sys->frame_size); 492 493 offset = avio_seek(s->pb, offset, SEEK_SET); 494 return (offset < 0) ? offset : 0; 495} 496 497static int dv_read_close(AVFormatContext *s) 498{ 499 RawDVContext *c = s->priv_data; 500 av_free(c->dv_demux); 501 return 0; 502} 503 504static int dv_probe(AVProbeData *p) 505{ 506 unsigned state, marker_pos = 0; 507 int i; 508 int matches = 0; 509 int secondary_matches = 0; 510 511 if (p->buf_size < 5) 512 return 0; 513 514 state = AV_RB32(p->buf); 515 for (i = 4; i < p->buf_size; i++) { 516 if ((state & 0xffffff7f) == 0x1f07003f) 517 matches++; 518 // any section header, also with seq/chan num != 0, 519 // should appear around every 12000 bytes, at least 10 per frame 520 if ((state & 0xff07ff7f) == 0x1f07003f) 521 secondary_matches++; 522 if (state == 0x003f0700 || state == 0xff3f0700) 523 marker_pos = i; 524 if (state == 0xff3f0701 && i - marker_pos == 80) 525 matches++; 526 state = (state << 8) | p->buf[i]; 527 } 528 529 if (matches && p->buf_size / matches < 1024*1024) { 530 if (matches > 4 || (secondary_matches >= 10 && p->buf_size / secondary_matches < 24000)) 531 return AVPROBE_SCORE_MAX*3/4; // not max to avoid dv in mov to match 532 return AVPROBE_SCORE_MAX/4; 533 } 534 return 0; 535} 536 537#if CONFIG_DV_DEMUXER 538AVInputFormat ff_dv_demuxer = { 539 .name = "dv", 540 .long_name = NULL_IF_CONFIG_SMALL("DV video format"), 541 .priv_data_size = sizeof(RawDVContext), 542 .read_probe = dv_probe, 543 .read_header = dv_read_header, 544 .read_packet = dv_read_packet, 545 .read_close = dv_read_close, 546 .read_seek = dv_read_seek, 547 .extensions = "dv,dif", 548}; 549#endif 550