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 * @return 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 = AVMEDIA_TYPE_VIDEO; 319 st->codec->codec_id = ff_codec_get_id(ff_codec_bmp_tags, tmp); 320 break; 321 case 1: 322 st->codec->codec_type = AVMEDIA_TYPE_AUDIO; 323 st->codec->codec_id = ff_codec_get_id(ff_codec_wav_tags, tmp); 324 break; 325 case 2: 326 st->codec->codec_type = AVMEDIA_TYPE_SUBTITLE; 327 st->codec->codec_id = ff_codec_get_id(ff_nut_subtitle_tags, tmp); 328 break; 329 case 3: 330 st->codec->codec_type = AVMEDIA_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 tag '0x%04x' for stream number %d\n", 338 (unsigned int)tmp, stream_id); 339 340 GET_V(stc->time_base_id , tmp < nut->time_base_count); 341 GET_V(stc->msb_pts_shift , tmp < 16); 342 stc->max_pts_distance= ff_get_v(bc); 343 GET_V(stc->decode_delay , tmp < 1000); //sanity limit, raise this if Moore's law is true 344 st->codec->has_b_frames= stc->decode_delay; 345 ff_get_v(bc); //stream flags 346 347 GET_V(st->codec->extradata_size, tmp < (1<<30)); 348 if(st->codec->extradata_size){ 349 st->codec->extradata= av_mallocz(st->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE); 350 get_buffer(bc, st->codec->extradata, st->codec->extradata_size); 351 } 352 353 if (st->codec->codec_type == AVMEDIA_TYPE_VIDEO){ 354 GET_V(st->codec->width , tmp > 0) 355 GET_V(st->codec->height, tmp > 0) 356 st->sample_aspect_ratio.num= ff_get_v(bc); 357 st->sample_aspect_ratio.den= ff_get_v(bc); 358 if((!st->sample_aspect_ratio.num) != (!st->sample_aspect_ratio.den)){ 359 av_log(s, AV_LOG_ERROR, "invalid aspect ratio %d/%d\n", st->sample_aspect_ratio.num, st->sample_aspect_ratio.den); 360 return -1; 361 } 362 ff_get_v(bc); /* csp type */ 363 }else if (st->codec->codec_type == AVMEDIA_TYPE_AUDIO){ 364 GET_V(st->codec->sample_rate , tmp > 0) 365 ff_get_v(bc); // samplerate_den 366 GET_V(st->codec->channels, tmp > 0) 367 } 368 if(skip_reserved(bc, end) || get_checksum(bc)){ 369 av_log(s, AV_LOG_ERROR, "stream header %d checksum mismatch\n", stream_id); 370 return -1; 371 } 372 stc->time_base= &nut->time_base[stc->time_base_id]; 373 av_set_pts_info(s->streams[stream_id], 63, stc->time_base->num, stc->time_base->den); 374 return 0; 375} 376 377static void set_disposition_bits(AVFormatContext* avf, char* value, int stream_id){ 378 int flag = 0, i; 379 for (i=0; ff_nut_dispositions[i].flag; ++i) { 380 if (!strcmp(ff_nut_dispositions[i].str, value)) 381 flag = ff_nut_dispositions[i].flag; 382 } 383 if (!flag) 384 av_log(avf, AV_LOG_INFO, "unknown disposition type '%s'\n", value); 385 for (i = 0; i < avf->nb_streams; ++i) 386 if (stream_id == i || stream_id == -1) 387 avf->streams[i]->disposition |= flag; 388} 389 390static int decode_info_header(NUTContext *nut){ 391 AVFormatContext *s= nut->avf; 392 ByteIOContext *bc = s->pb; 393 uint64_t tmp, chapter_start, chapter_len; 394 unsigned int stream_id_plus1, count; 395 int chapter_id, i; 396 int64_t value, end; 397 char name[256], str_value[1024], type_str[256]; 398 const char *type; 399 AVChapter *chapter= NULL; 400 AVStream *st= NULL; 401 402 end= get_packetheader(nut, bc, 1, INFO_STARTCODE); 403 end += url_ftell(bc); 404 405 GET_V(stream_id_plus1, tmp <= s->nb_streams) 406 chapter_id = get_s(bc); 407 chapter_start= ff_get_v(bc); 408 chapter_len = ff_get_v(bc); 409 count = ff_get_v(bc); 410 411 if(chapter_id && !stream_id_plus1){ 412 int64_t start= chapter_start / nut->time_base_count; 413 chapter= ff_new_chapter(s, chapter_id, 414 nut->time_base[chapter_start % nut->time_base_count], 415 start, start + chapter_len, NULL); 416 } else if(stream_id_plus1) 417 st= s->streams[stream_id_plus1 - 1]; 418 419 for(i=0; i<count; i++){ 420 get_str(bc, name, sizeof(name)); 421 value= get_s(bc); 422 if(value == -1){ 423 type= "UTF-8"; 424 get_str(bc, str_value, sizeof(str_value)); 425 }else if(value == -2){ 426 get_str(bc, type_str, sizeof(type_str)); 427 type= type_str; 428 get_str(bc, str_value, sizeof(str_value)); 429 }else if(value == -3){ 430 type= "s"; 431 value= get_s(bc); 432 }else if(value == -4){ 433 type= "t"; 434 value= ff_get_v(bc); 435 }else if(value < -4){ 436 type= "r"; 437 get_s(bc); 438 }else{ 439 type= "v"; 440 } 441 442 if (stream_id_plus1 > s->nb_streams) { 443 av_log(s, AV_LOG_ERROR, "invalid stream id for info packet\n"); 444 continue; 445 } 446 447 if(!strcmp(type, "UTF-8")){ 448 AVMetadata **metadata = NULL; 449 if(chapter_id==0 && !strcmp(name, "Disposition")) 450 set_disposition_bits(s, str_value, stream_id_plus1 - 1); 451 else if(chapter) metadata= &chapter->metadata; 452 else if(stream_id_plus1) metadata= &st->metadata; 453 else metadata= &s->metadata; 454 if(metadata && strcasecmp(name,"Uses") 455 && strcasecmp(name,"Depends") && strcasecmp(name,"Replaces")) 456 av_metadata_set2(metadata, name, str_value, 0); 457 } 458 } 459 460 if(skip_reserved(bc, end) || get_checksum(bc)){ 461 av_log(s, AV_LOG_ERROR, "info header checksum mismatch\n"); 462 return -1; 463 } 464 return 0; 465} 466 467static int decode_syncpoint(NUTContext *nut, int64_t *ts, int64_t *back_ptr){ 468 AVFormatContext *s= nut->avf; 469 ByteIOContext *bc = s->pb; 470 int64_t end, tmp; 471 472 nut->last_syncpoint_pos= url_ftell(bc)-8; 473 474 end= get_packetheader(nut, bc, 1, SYNCPOINT_STARTCODE); 475 end += url_ftell(bc); 476 477 tmp= ff_get_v(bc); 478 *back_ptr= nut->last_syncpoint_pos - 16*ff_get_v(bc); 479 if(*back_ptr < 0) 480 return -1; 481 482 ff_nut_reset_ts(nut, nut->time_base[tmp % nut->time_base_count], tmp / nut->time_base_count); 483 484 if(skip_reserved(bc, end) || get_checksum(bc)){ 485 av_log(s, AV_LOG_ERROR, "sync point checksum mismatch\n"); 486 return -1; 487 } 488 489 *ts= tmp / s->nb_streams * av_q2d(nut->time_base[tmp % s->nb_streams])*AV_TIME_BASE; 490 ff_nut_add_sp(nut, nut->last_syncpoint_pos, *back_ptr, *ts); 491 492 return 0; 493} 494 495static int find_and_decode_index(NUTContext *nut){ 496 AVFormatContext *s= nut->avf; 497 ByteIOContext *bc = s->pb; 498 uint64_t tmp, end; 499 int i, j, syncpoint_count; 500 int64_t filesize= url_fsize(bc); 501 int64_t *syncpoints; 502 int8_t *has_keyframe; 503 int ret= -1; 504 505 url_fseek(bc, filesize-12, SEEK_SET); 506 url_fseek(bc, filesize-get_be64(bc), SEEK_SET); 507 if(get_be64(bc) != INDEX_STARTCODE){ 508 av_log(s, AV_LOG_ERROR, "no index at the end\n"); 509 return -1; 510 } 511 512 end= get_packetheader(nut, bc, 1, INDEX_STARTCODE); 513 end += url_ftell(bc); 514 515 ff_get_v(bc); //max_pts 516 GET_V(syncpoint_count, tmp < INT_MAX/8 && tmp > 0) 517 syncpoints= av_malloc(sizeof(int64_t)*syncpoint_count); 518 has_keyframe= av_malloc(sizeof(int8_t)*(syncpoint_count+1)); 519 for(i=0; i<syncpoint_count; i++){ 520 syncpoints[i] = ff_get_v(bc); 521 if(syncpoints[i] <= 0) 522 goto fail; 523 if(i) 524 syncpoints[i] += syncpoints[i-1]; 525 } 526 527 for(i=0; i<s->nb_streams; i++){ 528 int64_t last_pts= -1; 529 for(j=0; j<syncpoint_count;){ 530 uint64_t x= ff_get_v(bc); 531 int type= x&1; 532 int n= j; 533 x>>=1; 534 if(type){ 535 int flag= x&1; 536 x>>=1; 537 if(n+x >= syncpoint_count + 1){ 538 av_log(s, AV_LOG_ERROR, "index overflow A\n"); 539 goto fail; 540 } 541 while(x--) 542 has_keyframe[n++]= flag; 543 has_keyframe[n++]= !flag; 544 }else{ 545 while(x != 1){ 546 if(n>=syncpoint_count + 1){ 547 av_log(s, AV_LOG_ERROR, "index overflow B\n"); 548 goto fail; 549 } 550 has_keyframe[n++]= x&1; 551 x>>=1; 552 } 553 } 554 if(has_keyframe[0]){ 555 av_log(s, AV_LOG_ERROR, "keyframe before first syncpoint in index\n"); 556 goto fail; 557 } 558 assert(n<=syncpoint_count+1); 559 for(; j<n && j<syncpoint_count; j++){ 560 if(has_keyframe[j]){ 561 uint64_t B, A= ff_get_v(bc); 562 if(!A){ 563 A= ff_get_v(bc); 564 B= ff_get_v(bc); 565 //eor_pts[j][i] = last_pts + A + B 566 }else 567 B= 0; 568 av_add_index_entry( 569 s->streams[i], 570 16*syncpoints[j-1], 571 last_pts + A, 572 0, 573 0, 574 AVINDEX_KEYFRAME); 575 last_pts += A + B; 576 } 577 } 578 } 579 } 580 581 if(skip_reserved(bc, end) || get_checksum(bc)){ 582 av_log(s, AV_LOG_ERROR, "index checksum mismatch\n"); 583 goto fail; 584 } 585 ret= 0; 586fail: 587 av_free(syncpoints); 588 av_free(has_keyframe); 589 return ret; 590} 591 592static int nut_read_header(AVFormatContext *s, AVFormatParameters *ap) 593{ 594 NUTContext *nut = s->priv_data; 595 ByteIOContext *bc = s->pb; 596 int64_t pos; 597 int initialized_stream_count; 598 599 nut->avf= s; 600 601 /* main header */ 602 pos=0; 603 do{ 604 pos= find_startcode(bc, MAIN_STARTCODE, pos)+1; 605 if (pos<0+1){ 606 av_log(s, AV_LOG_ERROR, "No main startcode found.\n"); 607 return -1; 608 } 609 }while(decode_main_header(nut) < 0); 610 611 /* stream headers */ 612 pos=0; 613 for(initialized_stream_count=0; initialized_stream_count < s->nb_streams;){ 614 pos= find_startcode(bc, STREAM_STARTCODE, pos)+1; 615 if (pos<0+1){ 616 av_log(s, AV_LOG_ERROR, "Not all stream headers found.\n"); 617 return -1; 618 } 619 if(decode_stream_header(nut) >= 0) 620 initialized_stream_count++; 621 } 622 623 /* info headers */ 624 pos=0; 625 for(;;){ 626 uint64_t startcode= find_any_startcode(bc, pos); 627 pos= url_ftell(bc); 628 629 if(startcode==0){ 630 av_log(s, AV_LOG_ERROR, "EOF before video frames\n"); 631 return -1; 632 }else if(startcode == SYNCPOINT_STARTCODE){ 633 nut->next_startcode= startcode; 634 break; 635 }else if(startcode != INFO_STARTCODE){ 636 continue; 637 } 638 639 decode_info_header(nut); 640 } 641 642 s->data_offset= pos-8; 643 644 if(!url_is_streamed(bc)){ 645 int64_t orig_pos= url_ftell(bc); 646 find_and_decode_index(nut); 647 url_fseek(bc, orig_pos, SEEK_SET); 648 } 649 assert(nut->next_startcode == SYNCPOINT_STARTCODE); 650 651 return 0; 652} 653 654static int decode_frame_header(NUTContext *nut, int64_t *pts, int *stream_id, uint8_t *header_idx, int frame_code){ 655 AVFormatContext *s= nut->avf; 656 ByteIOContext *bc = s->pb; 657 StreamContext *stc; 658 int size, flags, size_mul, pts_delta, i, reserved_count; 659 uint64_t tmp; 660 661 if(url_ftell(bc) > nut->last_syncpoint_pos + nut->max_distance){ 662 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); 663 return -1; 664 } 665 666 flags = nut->frame_code[frame_code].flags; 667 size_mul = nut->frame_code[frame_code].size_mul; 668 size = nut->frame_code[frame_code].size_lsb; 669 *stream_id = nut->frame_code[frame_code].stream_id; 670 pts_delta = nut->frame_code[frame_code].pts_delta; 671 reserved_count = nut->frame_code[frame_code].reserved_count; 672 *header_idx = nut->frame_code[frame_code].header_idx; 673 674 if(flags & FLAG_INVALID) 675 return -1; 676 if(flags & FLAG_CODED) 677 flags ^= ff_get_v(bc); 678 if(flags & FLAG_STREAM_ID){ 679 GET_V(*stream_id, tmp < s->nb_streams) 680 } 681 stc= &nut->stream[*stream_id]; 682 if(flags&FLAG_CODED_PTS){ 683 int coded_pts= ff_get_v(bc); 684//FIXME check last_pts validity? 685 if(coded_pts < (1<<stc->msb_pts_shift)){ 686 *pts=ff_lsb2full(stc, coded_pts); 687 }else 688 *pts=coded_pts - (1<<stc->msb_pts_shift); 689 }else 690 *pts= stc->last_pts + pts_delta; 691 if(flags&FLAG_SIZE_MSB){ 692 size += size_mul*ff_get_v(bc); 693 } 694 if(flags&FLAG_MATCH_TIME) 695 get_s(bc); 696 if(flags&FLAG_HEADER_IDX) 697 *header_idx= ff_get_v(bc); 698 if(flags&FLAG_RESERVED) 699 reserved_count= ff_get_v(bc); 700 for(i=0; i<reserved_count; i++) 701 ff_get_v(bc); 702 703 if(*header_idx >= (unsigned)nut->header_count){ 704 av_log(s, AV_LOG_ERROR, "header_idx invalid\n"); 705 return -1; 706 } 707 if(size > 4096) 708 *header_idx=0; 709 size -= nut->header_len[*header_idx]; 710 711 if(flags&FLAG_CHECKSUM){ 712 get_be32(bc); //FIXME check this 713 }else if(size > 2*nut->max_distance || FFABS(stc->last_pts - *pts) > stc->max_pts_distance){ 714 av_log(s, AV_LOG_ERROR, "frame size > 2max_distance and no checksum\n"); 715 return -1; 716 } 717 718 stc->last_pts= *pts; 719 stc->last_flags= flags; 720 721 return size; 722} 723 724static int decode_frame(NUTContext *nut, AVPacket *pkt, int frame_code){ 725 AVFormatContext *s= nut->avf; 726 ByteIOContext *bc = s->pb; 727 int size, stream_id, discard; 728 int64_t pts, last_IP_pts; 729 StreamContext *stc; 730 uint8_t header_idx; 731 732 size= decode_frame_header(nut, &pts, &stream_id, &header_idx, frame_code); 733 if(size < 0) 734 return -1; 735 736 stc= &nut->stream[stream_id]; 737 738 if (stc->last_flags & FLAG_KEY) 739 stc->skip_until_key_frame=0; 740 741 discard= s->streams[ stream_id ]->discard; 742 last_IP_pts= s->streams[ stream_id ]->last_IP_pts; 743 if( (discard >= AVDISCARD_NONKEY && !(stc->last_flags & FLAG_KEY)) 744 ||(discard >= AVDISCARD_BIDIR && last_IP_pts != AV_NOPTS_VALUE && last_IP_pts > pts) 745 || discard >= AVDISCARD_ALL 746 || stc->skip_until_key_frame){ 747 url_fskip(bc, size); 748 return 1; 749 } 750 751 av_new_packet(pkt, size + nut->header_len[header_idx]); 752 memcpy(pkt->data, nut->header[header_idx], nut->header_len[header_idx]); 753 pkt->pos= url_ftell(bc); //FIXME 754 get_buffer(bc, pkt->data + nut->header_len[header_idx], size); 755 756 pkt->stream_index = stream_id; 757 if (stc->last_flags & FLAG_KEY) 758 pkt->flags |= AV_PKT_FLAG_KEY; 759 pkt->pts = pts; 760 761 return 0; 762} 763 764static int nut_read_packet(AVFormatContext *s, AVPacket *pkt) 765{ 766 NUTContext *nut = s->priv_data; 767 ByteIOContext *bc = s->pb; 768 int i, frame_code=0, ret, skip; 769 int64_t ts, back_ptr; 770 771 for(;;){ 772 int64_t pos= url_ftell(bc); 773 uint64_t tmp= nut->next_startcode; 774 nut->next_startcode=0; 775 776 if(tmp){ 777 pos-=8; 778 }else{ 779 frame_code = get_byte(bc); 780 if(url_feof(bc)) 781 return -1; 782 if(frame_code == 'N'){ 783 tmp= frame_code; 784 for(i=1; i<8; i++) 785 tmp = (tmp<<8) + get_byte(bc); 786 } 787 } 788 switch(tmp){ 789 case MAIN_STARTCODE: 790 case STREAM_STARTCODE: 791 case INDEX_STARTCODE: 792 skip= get_packetheader(nut, bc, 0, tmp); 793 url_fseek(bc, skip, SEEK_CUR); 794 break; 795 case INFO_STARTCODE: 796 if(decode_info_header(nut)<0) 797 goto resync; 798 break; 799 case SYNCPOINT_STARTCODE: 800 if(decode_syncpoint(nut, &ts, &back_ptr)<0) 801 goto resync; 802 frame_code = get_byte(bc); 803 case 0: 804 ret= decode_frame(nut, pkt, frame_code); 805 if(ret==0) 806 return 0; 807 else if(ret==1) //ok but discard packet 808 break; 809 default: 810resync: 811av_log(s, AV_LOG_DEBUG, "syncing from %"PRId64"\n", pos); 812 tmp= find_any_startcode(bc, nut->last_syncpoint_pos+1); 813 if(tmp==0) 814 return -1; 815av_log(s, AV_LOG_DEBUG, "sync\n"); 816 nut->next_startcode= tmp; 817 } 818 } 819} 820 821static int64_t nut_read_timestamp(AVFormatContext *s, int stream_index, int64_t *pos_arg, int64_t pos_limit){ 822 NUTContext *nut = s->priv_data; 823 ByteIOContext *bc = s->pb; 824 int64_t pos, pts, back_ptr; 825av_log(s, AV_LOG_DEBUG, "read_timestamp(X,%d,%"PRId64",%"PRId64")\n", stream_index, *pos_arg, pos_limit); 826 827 pos= *pos_arg; 828 do{ 829 pos= find_startcode(bc, SYNCPOINT_STARTCODE, pos)+1; 830 if(pos < 1){ 831 assert(nut->next_startcode == 0); 832 av_log(s, AV_LOG_ERROR, "read_timestamp failed.\n"); 833 return AV_NOPTS_VALUE; 834 } 835 }while(decode_syncpoint(nut, &pts, &back_ptr) < 0); 836 *pos_arg = pos-1; 837 assert(nut->last_syncpoint_pos == *pos_arg); 838 839 av_log(s, AV_LOG_DEBUG, "return %"PRId64" %"PRId64"\n", pts,back_ptr ); 840 if (stream_index == -1) return pts; 841 else if(stream_index == -2) return back_ptr; 842 843assert(0); 844} 845 846static int read_seek(AVFormatContext *s, int stream_index, int64_t pts, int flags){ 847 NUTContext *nut = s->priv_data; 848 AVStream *st= s->streams[stream_index]; 849 Syncpoint dummy={.ts= pts*av_q2d(st->time_base)*AV_TIME_BASE}; 850 Syncpoint nopts_sp= {.ts= AV_NOPTS_VALUE, .back_ptr= AV_NOPTS_VALUE}; 851 Syncpoint *sp, *next_node[2]= {&nopts_sp, &nopts_sp}; 852 int64_t pos, pos2, ts; 853 int i; 854 855 if(st->index_entries){ 856 int index= av_index_search_timestamp(st, pts, flags); 857 if(index<0) 858 return -1; 859 860 pos2= st->index_entries[index].pos; 861 ts = st->index_entries[index].timestamp; 862 }else{ 863 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pts_cmp, 864 (void **) next_node); 865 av_log(s, AV_LOG_DEBUG, "%"PRIu64"-%"PRIu64" %"PRId64"-%"PRId64"\n", next_node[0]->pos, next_node[1]->pos, 866 next_node[0]->ts , next_node[1]->ts); 867 pos= av_gen_search(s, -1, dummy.ts, next_node[0]->pos, next_node[1]->pos, next_node[1]->pos, 868 next_node[0]->ts , next_node[1]->ts, AVSEEK_FLAG_BACKWARD, &ts, nut_read_timestamp); 869 870 if(!(flags & AVSEEK_FLAG_BACKWARD)){ 871 dummy.pos= pos+16; 872 next_node[1]= &nopts_sp; 873 av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp, 874 (void **) next_node); 875 pos2= av_gen_search(s, -2, dummy.pos, next_node[0]->pos , next_node[1]->pos, next_node[1]->pos, 876 next_node[0]->back_ptr, next_node[1]->back_ptr, flags, &ts, nut_read_timestamp); 877 if(pos2>=0) 878 pos= pos2; 879 //FIXME dir but I think it does not matter 880 } 881 dummy.pos= pos; 882 sp= av_tree_find(nut->syncpoints, &dummy, (void *) ff_nut_sp_pos_cmp, 883 NULL); 884 885 assert(sp); 886 pos2= sp->back_ptr - 15; 887 } 888 av_log(NULL, AV_LOG_DEBUG, "SEEKTO: %"PRId64"\n", pos2); 889 pos= find_startcode(s->pb, SYNCPOINT_STARTCODE, pos2); 890 url_fseek(s->pb, pos, SEEK_SET); 891 av_log(NULL, AV_LOG_DEBUG, "SP: %"PRId64"\n", pos); 892 if(pos2 > pos || pos2 + 15 < pos){ 893 av_log(NULL, AV_LOG_ERROR, "no syncpoint at backptr pos\n"); 894 } 895 for(i=0; i<s->nb_streams; i++) 896 nut->stream[i].skip_until_key_frame=1; 897 898 return 0; 899} 900 901static int nut_read_close(AVFormatContext *s) 902{ 903 NUTContext *nut = s->priv_data; 904 int i; 905 906 av_freep(&nut->time_base); 907 av_freep(&nut->stream); 908 ff_nut_free_sp(nut); 909 for(i = 1; i < nut->header_count; i++) 910 av_freep(&nut->header[i]); 911 912 return 0; 913} 914 915#if CONFIG_NUT_DEMUXER 916AVInputFormat nut_demuxer = { 917 "nut", 918 NULL_IF_CONFIG_SMALL("NUT format"), 919 sizeof(NUTContext), 920 nut_probe, 921 nut_read_header, 922 nut_read_packet, 923 nut_read_close, 924 read_seek, 925 .extensions = "nut", 926 .metadata_conv = ff_nut_metadata_conv, 927}; 928#endif 929