1/* 2 * "NUT" Container Format demuxer 3 * Copyright (c) 2004-2006 Michael Niedermayer 4 * Copyright (c) 2003 Alex Beregszaszi 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 */ 22 23#include <strings.h> 24#include "libavutil/avstring.h" 25#include "libavutil/bswap.h" 26#include "libavutil/tree.h" 27#include "nut.h" 28 29#undef NDEBUG 30#include <assert.h> 31 32static int get_str(ByteIOContext *bc, char *string, unsigned int maxlen){ 33 unsigned int len= ff_get_v(bc); 34 35 if(len && maxlen) 36 get_buffer(bc, string, FFMIN(len, maxlen)); 37 while(len > maxlen){ 38 get_byte(bc); 39 len--; 40 } 41 42 if(maxlen) 43 string[FFMIN(len, maxlen-1)]= 0; 44 45 if(maxlen == len) 46 return -1; 47 else 48 return 0; 49} 50 51static int64_t get_s(ByteIOContext *bc){ 52 int64_t v = ff_get_v(bc) + 1; 53 54 if (v&1) return -(v>>1); 55 else return (v>>1); 56} 57 58static uint64_t get_fourcc(ByteIOContext *bc){ 59 unsigned int len= ff_get_v(bc); 60 61 if (len==2) return get_le16(bc); 62 else if(len==4) return get_le32(bc); 63 else return -1; 64} 65 66#ifdef TRACE 67static inline uint64_t get_v_trace(ByteIOContext *bc, char *file, char *func, int line){ 68 uint64_t v= ff_get_v(bc); 69 70 av_log(NULL, AV_LOG_DEBUG, "get_v %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line); 71 return v; 72} 73 74static inline int64_t get_s_trace(ByteIOContext *bc, char *file, char *func, int line){ 75 int64_t v= get_s(bc); 76 77 av_log(NULL, AV_LOG_DEBUG, "get_s %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line); 78 return v; 79} 80 81static inline uint64_t get_vb_trace(ByteIOContext *bc, char *file, char *func, int line){ 82 uint64_t v= get_vb(bc); 83 84 av_log(NULL, AV_LOG_DEBUG, "get_vb %5"PRId64" / %"PRIX64" in %s %s:%d\n", v, v, file, func, line); 85 return v; 86} 87#define ff_get_v(bc) get_v_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__) 88#define get_s(bc) get_s_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__) 89#define get_vb(bc) get_vb_trace(bc, __FILE__, __PRETTY_FUNCTION__, __LINE__) 90#endif 91 92static int get_packetheader(NUTContext *nut, ByteIOContext *bc, int calculate_checksum, uint64_t startcode) 93{ 94 int64_t size; 95// start= url_ftell(bc) - 8; 96 97 startcode= be2me_64(startcode); 98 startcode= ff_crc04C11DB7_update(0, &startcode, 8); 99 100 init_checksum(bc, ff_crc04C11DB7_update, startcode); 101 size= ff_get_v(bc); 102 if(size > 4096) 103 get_be32(bc); 104 if(get_checksum(bc) && size > 4096) 105 return -1; 106 107 init_checksum(bc, calculate_checksum ? ff_crc04C11DB7_update : NULL, 0); 108 109 return size; 110} 111 112static uint64_t find_any_startcode(ByteIOContext *bc, int64_t pos){ 113 uint64_t state=0; 114 115 if(pos >= 0) 116 url_fseek(bc, pos, SEEK_SET); //note, this may fail if the stream is not seekable, but that should not matter, as in this case we simply start where we currently are 117 118 while(!url_feof(bc)){ 119 state= (state<<8) | get_byte(bc); 120 if((state>>56) != 'N') 121 continue; 122 switch(state){ 123 case MAIN_STARTCODE: 124 case STREAM_STARTCODE: 125 case SYNCPOINT_STARTCODE: 126 case INFO_STARTCODE: 127 case INDEX_STARTCODE: 128 return state; 129 } 130 } 131 132 return 0; 133} 134 135/** 136 * Find the given startcode. 137 * @param code the startcode 138 * @param pos the start position of the search, or -1 if the current position 139 * @returns the position of the startcode or -1 if not found 140 */ 141static int64_t find_startcode(ByteIOContext *bc, uint64_t code, int64_t pos){ 142 for(;;){ 143 uint64_t startcode= find_any_startcode(bc, pos); 144 if(startcode == code) 145 return url_ftell(bc) - 8; 146 else if(startcode == 0) 147 return -1; 148 pos=-1; 149 } 150} 151 152static int nut_probe(AVProbeData *p){ 153 int i; 154 uint64_t code= 0; 155 156 for (i = 0; i < p->buf_size; i++) { 157 code = (code << 8) | p->buf[i]; 158 if (code == MAIN_STARTCODE) 159 return AVPROBE_SCORE_MAX; 160 } 161 return 0; 162} 163 164#define GET_V(dst, check) \ 165 tmp= ff_get_v(bc);\ 166 if(!(check)){\ 167 av_log(s, AV_LOG_ERROR, "Error " #dst " is (%"PRId64")\n", tmp);\ 168 return -1;\ 169 }\ 170 dst= tmp; 171 172static int skip_reserved(ByteIOContext *bc, int64_t pos){ 173 pos -= url_ftell(bc); 174 if(pos<0){ 175 url_fseek(bc, pos, SEEK_CUR); 176 return -1; 177 }else{ 178 while(pos--) 179 get_byte(bc); 180 return 0; 181 } 182} 183 184static int decode_main_header(NUTContext *nut){ 185 AVFormatContext *s= nut->avf; 186 ByteIOContext *bc = s->pb; 187 uint64_t tmp, end; 188 unsigned int stream_count; 189 int i, j, tmp_stream, tmp_mul, tmp_pts, tmp_size, count, tmp_res, tmp_head_idx; 190 int64_t tmp_match; 191 192 end= get_packetheader(nut, bc, 1, MAIN_STARTCODE); 193 end += url_ftell(bc); 194 195 GET_V(tmp , tmp >=2 && tmp <= 3) 196 GET_V(stream_count , tmp > 0 && tmp <=MAX_STREAMS) 197 198 nut->max_distance = ff_get_v(bc); 199 if(nut->max_distance > 65536){ 200 av_log(s, AV_LOG_DEBUG, "max_distance %d\n", nut->max_distance); 201 nut->max_distance= 65536; 202 } 203 204 GET_V(nut->time_base_count, tmp>0 && tmp<INT_MAX / sizeof(AVRational)) 205 nut->time_base= av_malloc(nut->time_base_count * sizeof(AVRational)); 206 207 for(i=0; i<nut->time_base_count; i++){ 208 GET_V(nut->time_base[i].num, tmp>0 && tmp<(1ULL<<31)) 209 GET_V(nut->time_base[i].den, tmp>0 && tmp<(1ULL<<31)) 210 if(av_gcd(nut->time_base[i].num, nut->time_base[i].den) != 1){ 211 av_log(s, AV_LOG_ERROR, "time base invalid\n"); 212 return -1; 213 } 214 } 215 tmp_pts=0; 216 tmp_mul=1; 217 tmp_stream=0; 218 tmp_match= 1-(1LL<<62); 219 tmp_head_idx= 0; 220 for(i=0; i<256;){ 221 int tmp_flags = ff_get_v(bc); 222 int tmp_fields= ff_get_v(bc); 223 if(tmp_fields>0) tmp_pts = get_s(bc); 224 if(tmp_fields>1) tmp_mul = ff_get_v(bc); 225 if(tmp_fields>2) tmp_stream= ff_get_v(bc); 226 if(tmp_fields>3) tmp_size = ff_get_v(bc); 227 else tmp_size = 0; 228 if(tmp_fields>4) tmp_res = ff_get_v(bc); 229 else tmp_res = 0; 230 if(tmp_fields>5) count = ff_get_v(bc); 231 else count = tmp_mul - tmp_size; 232 if(tmp_fields>6) tmp_match = get_s(bc); 233 if(tmp_fields>7) tmp_head_idx= ff_get_v(bc); 234 235 while(tmp_fields-- > 8) 236 ff_get_v(bc); 237 238 if(count == 0 || i+count > 256){ 239 av_log(s, AV_LOG_ERROR, "illegal count %d at %d\n", count, i); 240 return -1; 241 } 242 if(tmp_stream >= stream_count){ 243 av_log(s, AV_LOG_ERROR, "illegal stream number\n"); 244 return -1; 245 } 246 247 for(j=0; j<count; j++,i++){ 248 if (i == 'N') { 249 nut->frame_code[i].flags= FLAG_INVALID; 250 j--; 251 continue; 252 } 253 nut->frame_code[i].flags = tmp_flags ; 254 nut->frame_code[i].pts_delta = tmp_pts ; 255 nut->frame_code[i].stream_id = tmp_stream; 256 nut->frame_code[i].size_mul = tmp_mul ; 257 nut->frame_code[i].size_lsb = tmp_size+j; 258 nut->frame_code[i].reserved_count = tmp_res ; 259 nut->frame_code[i].header_idx = tmp_head_idx; 260 } 261 } 262 assert(nut->frame_code['N'].flags == FLAG_INVALID); 263 264 if(end > url_ftell(bc) + 4){ 265 int rem= 1024; 266 GET_V(nut->header_count, tmp<128U) 267 nut->header_count++; 268 for(i=1; i<nut->header_count; i++){ 269 GET_V(nut->header_len[i], tmp>0 && tmp<256); 270 rem -= nut->header_len[i]; 271 if(rem < 0){ 272 av_log(s, AV_LOG_ERROR, "invalid elision header\n"); 273 return -1; 274 } 275 nut->header[i]= av_malloc(nut->header_len[i]); 276 get_buffer(bc, nut->header[i], nut->header_len[i]); 277 } 278 assert(nut->header_len[0]==0); 279 } 280 281 if(skip_reserved(bc, end) || get_checksum(bc)){ 282 av_log(s, AV_LOG_ERROR, "main header checksum mismatch\n"); 283 return -1; 284 } 285 286 nut->stream = av_mallocz(sizeof(StreamContext)*stream_count); 287 for(i=0; i<stream_count; i++){ 288 av_new_stream(s, i); 289 } 290 291 return 0; 292} 293 294static int decode_stream_header(NUTContext *nut){ 295 AVFormatContext *s= nut->avf; 296 ByteIOContext *bc = s->pb; 297 StreamContext *stc; 298 int class, stream_id; 299 uint64_t tmp, end; 300 AVStream *st; 301 302 end= get_packetheader(nut, bc, 1, STREAM_STARTCODE); 303 end += url_ftell(bc); 304 305 GET_V(stream_id, tmp < s->nb_streams && !nut->stream[tmp].time_base); 306 stc= &nut->stream[stream_id]; 307 308 st = s->streams[stream_id]; 309 if (!st) 310 return AVERROR(ENOMEM); 311 312 class = ff_get_v(bc); 313 tmp = get_fourcc(bc); 314 st->codec->codec_tag= tmp; 315 switch(class) 316 { 317 case 0: 318 st->codec->codec_type = CODEC_TYPE_VIDEO; 319 st->codec->codec_id = codec_get_id(codec_bmp_tags, tmp); 320 break; 321 case 1: 322 st->codec->codec_type = CODEC_TYPE_AUDIO; 323 st->codec->codec_id = codec_get_id(codec_wav_tags, tmp); 324 break; 325 case 2: 326 st->codec->codec_type = CODEC_TYPE_SUBTITLE; 327 st->codec->codec_id = codec_get_id(ff_nut_subtitle_tags, tmp); 328 break; 329 case 3: 330 st->codec->codec_type = CODEC_TYPE_DATA; 331 break; 332 default: 333 av_log(s, AV_LOG_ERROR, "unknown stream class (%d)\n", class); 334 return -1; 335 } 336 if(class<3 && st->codec->codec_id == CODEC_ID_NONE) 337 av_log(s, AV_LOG_ERROR, "Unknown codec?!\n"); 338 339 GET_V(stc->time_base_id , tmp < nut->time_base_count); 340 GET_V(stc->msb_pts_shift , tmp < 16); 341 stc->max_pts_distance= ff_get_v(bc); 342 GET_V(stc->decode_delay , tmp < 1000); //sanity limit, raise this if Moore's law is true 343 st->codec->has_b_frames= stc->decode_delay; 344 ff_get_v(bc); //stream flags 345 346 GET_V(st->codec->extradata_size, tmp < (1<<30)); 347 if(st->codec->extradata_size){ 348 st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE); 349 get_buffer(bc, st->codec->extradata, st->codec->extradata_size); 350 } 351 352 if (st->codec->codec_type == CODEC_TYPE_VIDEO){ 353 GET_V(st->codec->width , tmp > 0) 354 GET_V(st->codec->height, tmp > 0) 355 st->sample_aspect_ratio.num= ff_get_v(bc); 356 st->sample_aspect_ratio.den= ff_get_v(bc); 357 if((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)){ 358 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n", st->sample_aspect_ratio.num, st->sample_aspect_ratio.den); 359 return -1; 360 } 361 ff_get_v(bc); /* csp type */ 362 }else if (st->codec->codec_type == CODEC_TYPE_AUDIO){ 363 GET_V(st->codec->sample_rate , tmp > 0) 364 ff_get_v(bc); // samplerate_den 365 GET_V(st->codec->channels, tmp > 0) 366 } 367 if(skip_reserved(bc, end) || get_checksum(bc)){ 368 av_log(s, AV_LOG_ERROR, "stream header %d checksum mismatch\n", stream_id); 369 return -1; 370 } 371 stc->time_base= &nut->time_base[stc->time_base_id]; 372 av_set_pts_info(s->streams[stream_id], 63, stc->time_base->num, stc->time_base->den); 373 return 0; 374} 375 376static void set_disposition_bits(AVFormatContext* avf, char* value, int stream_id){ 377 int flag = 0, i; 378 for (i=0; ff_nut_dispositions[i].flag; ++i) { 379 if (!strcmp(ff_nut_dispositions[i].str, value)) 380 flag = ff_nut_dispositions[i].flag; 381 } 382 if (!flag) 383 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value); 384 for (i = 0; i < avf->nb_streams; ++i) 385 if (stream_id == i || stream_id == -1) 386 avf->streams[i]->disposition |= flag; 387} 388 389static int decode_info_header(NUTContext *nut){ 390 AVFormatContext *s= nut->avf; 391 ByteIOContext *bc = s->pb; 392 uint64_t tmp; 393 unsigned int stream_id_plus1, chapter_start, chapter_len, count; 394 int chapter_id, i; 395 int64_t value, end; 396 char name[256], str_value[1024], type_str[256]; 397 const char *type; 398 AVChapter *chapter= NULL; 399 AVStream *st= NULL; 400 401 end= get_packetheader(nut, bc, 1, INFO_STARTCODE); 402 end += url_ftell(bc); 403 404 GET_V(stream_id_plus1, tmp <= s->nb_streams) 405 chapter_id = get_s(bc); 406 chapter_start= ff_get_v(bc); 407 chapter_len = ff_get_v(bc); 408 count = ff_get_v(bc); 409 410 if(chapter_id && !stream_id_plus1){ 411 int64_t start= chapter_start / nut->time_base_count; 412 chapter= ff_new_chapter(s, chapter_id, 413 nut->time_base[chapter_start % nut->time_base_count], 414 start, start + chapter_len, NULL); 415 } else if(stream_id_plus1) 416 st= s->streams[stream_id_plus1 - 1]; 417 418 for(i=0; i<count; i++){ 419 get_str(bc, name, sizeof(name)); 420 value= get_s(bc); 421 if(value == -1){ 422 type= "UTF-8"; 423 get_str(bc, str_value, sizeof(str_value)); 424 }else if(value == -2){ 425 get_str(bc, type_str, sizeof(type_str)); 426 type= type_str; 427 get_str(bc, str_value, sizeof(str_value)); 428 }else if(value == -3){ 429 type= "s"; 430 value= get_s(bc); 431 }else if(value == -4){ 432 type= "t"; 433 value= ff_get_v(bc); 434 }else if(value < -4){ 435 type= "r"; 436 get_s(bc); 437 }else{ 438 type= "v"; 439 } 440 441 if (stream_id_plus1 > s->nb_streams) { 442 av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n"); 443 continue; 444 } 445 446 if(!strcmp(type, "UTF-8")){ 447 AVMetadata **metadata = NULL; 448 if(chapter_id==0 && !strcmp(name, "Disposition")) 449 set_disposition_bits(s, str_value, stream_id_plus1 - 1); 450 else if(chapter) metadata= &chapter->metadata; 451 else if(stream_id_plus1) metadata= &st->metadata; 452 else metadata= &s->metadata; 453 if(metadata && strcasecmp(name,"Uses") 454 && strcasecmp(name,"Depends") && strcasecmp(name,"Replaces")) 455 av_metadata_set(metadata, name, str_value); 456 } 457 } 458 459 if(skip_reserved(bc, end) || get_checksum(bc)){ 460 av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n"); 461 return -1; 462 } 463 return 0; 464} 465 466static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr){ 467 AVFormatContext *s= nut->avf; 468 ByteIOContext *bc = s->pb; 469 int64_t end, tmp; 470 471 nut->last_syncpoint_pos= url_ftell(bc)-8; 472 473 end= get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE); 474 end += url_ftell(bc); 475 476 tmp= ff_get_v(bc); 477 *back_ptr= nut->last_syncpoint_pos - 16*ff_get_v(bc); 478 if(*back_ptr < 0) 479 return -1; 480 481 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count], tmp / nut->time_base_count); 482 483 if(skip_reserved(bc, end) || get_checksum(bc)){ 484 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n"); 485 return -1; 486 } 487 488 *ts= tmp / s->nb_streams * av_q2d(nut->time_base[tmp % s->nb_streams])*AV_TIME_BASE; 489 ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts); 490 491 return 0; 492} 493 494static int find_and_decode_index(NUTContext *nut){ 495 AVFormatContext *s= nut->avf; 496 ByteIOContext *bc = s->pb; 497 uint64_t tmp, end; 498 int i, j, syncpoint_count; 499 int64_t filesize= url_fsize(bc); 500 int64_t *syncpoints; 501 int8_t *has_keyframe; 502 int ret= -1; 503 504 url_fseek(bc, filesize-12, SEEK_SET); 505 url_fseek(bc, filesize-get_be64(bc), SEEK_SET); 506 if(get_be64(bc) != INDEX_STARTCODE){ 507 av_log(s, AV_LOG_ERROR, "no index at the end\n"); 508 return -1; 509 } 510 511 end= get_packetheader(nut, bc, 1, INDEX_STARTCODE); 512 end += url_ftell(bc); 513 514 ff_get_v(bc); //max_pts 515 GET_V(syncpoint_count, tmp < INT_MAX/8 && tmp > 0) 516 syncpoints= av_malloc(sizeof(int64_t)*syncpoint_count); 517 has_keyframe= av_malloc(sizeof(int8_t)*(syncpoint_count+1)); 518 for(i=0; i<syncpoint_count; i++){ 519 syncpoints[i] = ff_get_v(bc); 520 if(syncpoints[i] <= 0) 521 goto fail; 522 if(i) 523 syncpoints[i] += syncpoints[i-1]; 524 } 525 526 for(i=0; i<s->nb_streams; i++){ 527 int64_t last_pts= -1; 528 for(j=0; j<syncpoint_count;){ 529 uint64_t x= ff_get_v(bc); 530 int type= x&1; 531 int n= j; 532 x>>=1; 533 if(type){ 534 int flag= x&1; 535 x>>=1; 536 if(n+x >= syncpoint_count + 1){ 537 av_log(s, AV_LOG_ERROR, "index overflow A\n"); 538 goto fail; 539 } 540 while(x--) 541 has_keyframe[n++]= flag; 542 has_keyframe[n++]= !flag; 543 }else{ 544 while(x != 1){ 545 if(n>=syncpoint_count + 1){ 546 av_log(s, AV_LOG_ERROR, "index overflow B\n"); 547 goto fail; 548 } 549 has_keyframe[n++]= x&1; 550 x>>=1; 551 } 552 } 553 if(has_keyframe[0]){ 554 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n"); 555 goto fail; 556 } 557 assert(n<=syncpoint_count+1); 558 for(; j<n && j<syncpoint_count; j++){ 559 if(has_keyframe[j]){ 560 uint64_t B, A= ff_get_v(bc); 561 if(!A){ 562 A= ff_get_v(bc); 563 B= ff_get_v(bc); 564 //eor_pts[j][i] = last_pts + A + B 565 }else 566 B= 0; 567 av_add_index_entry( 568 s->streams[i], 569 16*syncpoints[j-1], 570 last_pts + A, 571 0, 572 0, 573 AVINDEX_KEYFRAME); 574 last_pts += A + B; 575 } 576 } 577 } 578 } 579 580 if(skip_reserved(bc, end) || get_checksum(bc)){ 581 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n"); 582 goto fail; 583 } 584 ret= 0; 585fail: 586 av_free(syncpoints); 587 av_free(has_keyframe); 588 return ret; 589} 590 591static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap) 592{ 593 NUTContext *nut = s->priv_data; 594 ByteIOContext *bc = s->pb; 595 int64_t pos; 596 int initialized_stream_count; 597 598 nut->avf= s; 599 600 /* main header */ 601 pos=0; 602 do{ 603 pos= find_startcode(bc, MAIN_STARTCODE, pos)+1; 604 if (pos<0+1){ 605 av_log(s, AV_LOG_ERROR, "No main startcode found.\n"); 606 return -1; 607 } 608 }while(decode_main_header(nut) < 0); 609 610 /* stream headers */ 611 pos=0; 612 for(initialized_stream_count=0; initialized_stream_count < s->nb_streams;){ 613 pos= find_startcode(bc, STREAM_STARTCODE, pos)+1; 614 if (pos<0+1){ 615 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n"); 616 return -1; 617 } 618 if(decode_stream_header(nut) >= 0) 619 initialized_stream_count++; 620 } 621 622 /* info headers */ 623 pos=0; 624 for(;;){ 625 uint64_t startcode= find_any_startcode(bc, pos); 626 pos= url_ftell(bc); 627 628 if(startcode==0){ 629 av_log(s, AV_LOG_ERROR, "EOF before video frames\n"); 630 return -1; 631 }else if(startcode == SYNCPOINT_STARTCODE){ 632 nut->next_startcode= startcode; 633 break; 634 }else if(startcode != INFO_STARTCODE){ 635 continue; 636 } 637 638 decode_info_header(nut); 639 } 640 641 s->data_offset= pos-8; 642 643 if(!url_is_streamed(bc)){ 644 int64_t orig_pos= url_ftell(bc); 645 find_and_decode_index(nut); 646 url_fseek(bc, orig_pos, SEEK_SET); 647 } 648 assert(nut->next_startcode == SYNCPOINT_STARTCODE); 649 650 return 0; 651} 652 653static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id, uint8_t *header_idx, int frame_code){ 654 AVFormatContext *s= nut->avf; 655 ByteIOContext *bc = s->pb; 656 StreamContext *stc; 657 int size, flags, size_mul, pts_delta, i, reserved_count; 658 uint64_t tmp; 659 660 if(url_ftell(bc) > nut->last_syncpoint_pos + nut->max_distance){ 661 av_log(s, AV_LOG_ERROR, "Last frame must have been damaged %"PRId64" > %"PRId64" + %d\n", url_ftell(bc), nut->last_syncpoint_pos, nut->max_distance); 662 return -1; 663 } 664 665 flags = nut->frame_code[frame_code].flags; 666 size_mul = nut->frame_code[frame_code].size_mul; 667 size = nut->frame_code[frame_code].size_lsb; 668 *stream_id = nut->frame_code[frame_code].stream_id; 669 pts_delta = nut->frame_code[frame_code].pts_delta; 670 reserved_count = nut->frame_code[frame_code].reserved_count; 671 *header_idx = nut->frame_code[frame_code].header_idx; 672 673 if(flags & FLAG_INVALID) 674 return -1; 675 if(flags & FLAG_CODED) 676 flags ^= ff_get_v(bc); 677 if(flags & FLAG_STREAM_ID){ 678 GET_V(*stream_id, tmp < s->nb_streams) 679 } 680 stc= &nut->stream[*stream_id]; 681 if(flags&FLAG_CODED_PTS){ 682 int coded_pts= ff_get_v(bc); 683//FIXME check last_pts validity? 684 if(coded_pts < (1<<stc->msb_pts_shift)){ 685 *pts=ff_lsb2full(stc, coded_pts); 686 }else 687 *pts=coded_pts - (1<<stc->msb_pts_shift); 688 }else 689 *pts= stc->last_pts + pts_delta; 690 if(flags&FLAG_SIZE_MSB){ 691 size += size_mul*ff_get_v(bc); 692 } 693 if(flags&FLAG_MATCH_TIME) 694 get_s(bc); 695 if(flags&FLAG_HEADER_IDX) 696 *header_idx= ff_get_v(bc); 697 if(flags&FLAG_RESERVED) 698 reserved_count= ff_get_v(bc); 699 for(i=0; i<reserved_count; i++) 700 ff_get_v(bc); 701 702 if(*header_idx >= (unsigned)nut->header_count){ 703 av_log(s, AV_LOG_ERROR, "header_idx invalid\n"); 704 return -1; 705 } 706 if(size > 4096) 707 *header_idx=0; 708 size -= nut->header_len[*header_idx]; 709 710 if(flags&FLAG_CHECKSUM){ 711 get_be32(bc); //FIXME check this 712 }else if(size > 2*nut->max_distance || FFABS(stc->last_pts - *pts) > stc->max_pts_distance){ 713 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n"); 714 return -1; 715 } 716 717 stc->last_pts= *pts; 718 stc->last_flags= flags; 719 720 return size; 721} 722 723static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code){ 724 AVFormatContext *s= nut->avf; 725 ByteIOContext *bc = s->pb; 726 int size, stream_id, discard; 727 int64_t pts, last_IP_pts; 728 StreamContext *stc; 729 uint8_t header_idx; 730 731 size= decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code); 732 if(size < 0) 733 return -1; 734 735 stc= &nut->stream[stream_id]; 736 737 if (stc->last_flags & FLAG_KEY) 738 stc->skip_until_key_frame=0; 739 740 discard= s->streams[ stream_id ]->discard; 741 last_IP_pts= s->streams[ stream_id ]->last_IP_pts; 742 if( (discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) 743 ||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts) 744 || discard >= AVDISCARD_ALL 745 || stc->skip_until_key_frame){ 746 url_fskip(bc, size); 747 return 1; 748 } 749 750 av_new_packet(pkt, size + nut->header_len[header_idx]); 751 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]); 752 pkt->pos= url_ftell(bc); //FIXME 753 get_buffer(bc, pkt->data + nut->header_len[header_idx], size); 754 755 pkt->stream_index = stream_id; 756 if (stc->last_flags & FLAG_KEY) 757 pkt->flags |= PKT_FLAG_KEY; 758 pkt->pts = pts; 759 760 return 0; 761} 762 763static int nut_read_packet(AVFormatContext *s, AVPacket *pkt) 764{ 765 NUTContext *nut = s->priv_data; 766 ByteIOContext *bc = s->pb; 767 int i, frame_code=0, ret, skip; 768 int64_t ts, back_ptr; 769 770 for(;;){ 771 int64_t pos= url_ftell(bc); 772 uint64_t tmp= nut->next_startcode; 773 nut->next_startcode=0; 774 775 if(tmp){ 776 pos-=8; 777 }else{ 778 frame_code = get_byte(bc); 779 if(url_feof(bc)) 780 return -1; 781 if(frame_code == 'N'){ 782 tmp= frame_code; 783 for(i=1; i<8; i++) 784 tmp = (tmp<<8) + get_byte(bc); 785 } 786 } 787 switch(tmp){ 788 case MAIN_STARTCODE: 789 case STREAM_STARTCODE: 790 case INDEX_STARTCODE: 791 skip= get_packetheader(nut, bc, 0, tmp); 792 url_fseek(bc, skip, SEEK_CUR); 793 break; 794 case INFO_STARTCODE: 795 if(decode_info_header(nut)<0) 796 goto resync; 797 break; 798 case SYNCPOINT_STARTCODE: 799 if(decode_syncpoint(nut, &ts, &back_ptr)<0) 800 goto resync; 801 frame_code = get_byte(bc); 802 case 0: 803 ret= decode_frame(nut, pkt, frame_code); 804 if(ret==0) 805 return 0; 806 else if(ret==1) //ok but discard packet 807 break; 808 default: 809resync: 810av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos); 811 tmp= find_any_startcode(bc, nut->last_syncpoint_pos+1); 812 if(tmp==0) 813 return -1; 814av_log(s, AV_LOG_DEBUG, "sync\n"); 815 nut->next_startcode= tmp; 816 } 817 } 818} 819 820static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){ 821 NUTContext *nut = s->priv_data; 822 ByteIOContext *bc = s->pb; 823 int64_t pos, pts, back_ptr; 824av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit); 825 826 pos= *pos_arg; 827 do{ 828 pos= find_startcode(bc, SYNCPOINT_STARTCODE, pos)+1; 829 if(pos < 1){ 830 assert(nut->next_startcode == 0); 831 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n"); 832 return AV_NOPTS_VALUE; 833 } 834 }while(decode_syncpoint(nut, &pts, &back_ptr) < 0); 835 *pos_arg = pos-1; 836 assert(nut->last_syncpoint_pos == *pos_arg); 837 838 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts,back_ptr ); 839 if (stream_index == -1) return pts; 840 else if(stream_index == -2) return back_ptr; 841 842assert(0); 843} 844 845static int read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags){ 846 NUTContext *nut = s->priv_data; 847 AVStream *st= s->streams[stream_index]; 848 Syncpoint dummy={.ts= pts*av_q2d(st->time_base)*AV_TIME_BASE}; 849 Syncpoint nopts_sp= {.ts= AV_NOPTS_VALUE, .back_ptr= AV_NOPTS_VALUE}; 850 Syncpoint *sp, *next_node[2]= {&nopts_sp, &nopts_sp}; 851 int64_t pos, pos2, ts; 852 int i; 853 854 if(st->index_entries){ 855 int index= av_index_search_timestamp(st, pts, flags); 856 if(index<0) 857 return -1; 858 859 pos2= st->index_entries[index].pos; 860 ts = st->index_entries[index].timestamp; 861 }else{ 862 av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pts_cmp, next_node); 863 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n", next_node[0]->pos, next_node[1]->pos, 864 next_node[0]->ts , next_node[1]->ts); 865 pos= av_gen_search(s, -1, dummy.ts, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos, 866 next_node[0]->ts , next_node[1]->ts, AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp); 867 868 if(!(flags & AVSEEK_FLAG_BACKWARD)){ 869 dummy.pos= pos+16; 870 next_node[1]= &nopts_sp; 871 av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pos_cmp, next_node); 872 pos2= av_gen_search(s, -2, dummy.pos, next_node[0]->pos , next_node[1]->pos, next_node[1]->pos, 873 next_node[0]->back_ptr, next_node[1]->back_ptr, flags, &ts, nut_read_timestamp); 874 if(pos2>=0) 875 pos= pos2; 876 //FIXME dir but I think it does not matter 877 } 878 dummy.pos= pos; 879 sp= av_tree_find(nut->syncpoints, &dummy, ff_nut_sp_pos_cmp, NULL); 880 881 assert(sp); 882 pos2= sp->back_ptr - 15; 883 } 884 av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2); 885 pos= find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2); 886 url_fseek(s->pb, pos, SEEK_SET); 887 av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos); 888 if(pos2 > pos || pos2 + 15 < pos){ 889 av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n"); 890 } 891 for(i=0; i<s->nb_streams; i++) 892 nut->stream[i].skip_until_key_frame=1; 893 894 return 0; 895} 896 897static int nut_read_close(AVFormatContext *s) 898{ 899 NUTContext *nut = s->priv_data; 900 901 av_freep(&nut->time_base); 902 av_freep(&nut->stream); 903 904 return 0; 905} 906 907#if CONFIG_NUT_DEMUXER 908AVInputFormat nut_demuxer = { 909 "nut", 910 NULL_IF_CONFIG_SMALL("NUT format"), 911 sizeof(NUTContext), 912 nut_probe, 913 nut_read_header, 914 nut_read_packet, 915 nut_read_close, 916 read_seek, 917 .extensions = "nut", 918}; 919#endif 920