libavformat/mpeg.c

   1 /*
   2  * MPEG-1/2 demuxer
   3  * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
   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  */
  21
  22 #include "avformat.h"
  23 #include "internal.h"
  24 #include "mpeg.h"
  25
  26 #if CONFIG_VOBSUB_DEMUXER
  27 # include "subtitles.h"
  28 # include "libavutil/bprint.h"
  29 # include "libavutil/opt.h"
  30 #endif
  31
  32 #include "libavutil/avassert.h"
  33
  34 /*********************************************/
  35 /* demux code */
  36
  37 #define MAX_SYNC_SIZE 100000
  38
  39 static int check_pes(const uint8_t *p, const uint8_t *end)
  40 {
  41     int pes1;
  42     int pes2 = (p[3] & 0xC0) == 0x80 &&
  43                (p[4] & 0xC0) != 0x40 &&
  44                ((p[4] & 0xC0) == 0x00 ||
  45                 (p[4] & 0xC0) >> 2 == (p[6] & 0xF0));
  46
  47     for (p += 3; p < end && *p == 0xFF; p++) ;
  48     if ((*p & 0xC0) == 0x40)
  49         p += 2;
  50
  51     if ((*p & 0xF0) == 0x20)
  52         pes1 = p[0] & p[2] & p[4] & 1;
  53     else if ((*p & 0xF0) == 0x30)
  54         pes1 = p[0] & p[2] & p[4] & p[5] & p[7] & p[9] & 1;
  55     else
  56         pes1 = *p == 0x0F;
  57
  58     return pes1 || pes2;
  59 }
  60
  61 static int check_pack_header(const uint8_t *buf)
  62 {
  63     return (buf[1] & 0xC0) == 0x40 || (buf[1] & 0xF0) == 0x20;
  64 }
  65
  66 static int mpegps_probe(AVProbeData *p)
  67 {
  68     uint32_t code = -1;
  69     int i;
  70     int sys = 0, pspack = 0, priv1 = 0, vid = 0;
  71     int audio = 0, invalid = 0, score = 0;
  72     int endpes = 0;
  73
  74     for (i = 0; i < p->buf_size; i++) {
  75         code = (code << 8) + p->buf[i];
  76         if ((code & 0xffffff00) == 0x100) {
  77             int len  = p->buf[i + 1] << 8 | p->buf[i + 2];
  78             int pes  = endpes <= i && check_pes(p->buf + i, p->buf + p->buf_size);
  79             int pack = check_pack_header(p->buf + i);
  80
  81             if (code == SYSTEM_HEADER_START_CODE)
  82                 sys++;
  83             else if (code == PACK_START_CODE && pack)
  84                 pspack++;
  85             else if ((code & 0xf0) == VIDEO_ID && pes) {
  86                 endpes = i + len;
  87                 vid++;
  88             }
  89             // skip pes payload to avoid start code emulation for private
  90             // and audio streams
  91             else if ((code & 0xe0) == AUDIO_ID &&  pes) {audio++; i+=len;}
  92             else if (code == PRIVATE_STREAM_1  &&  pes) {priv1++; i+=len;}
  93             else if (code == 0x1fd             &&  pes) vid++; //VC1
  94
  95             else if ((code & 0xf0) == VIDEO_ID && !pes) invalid++;
  96             else if ((code & 0xe0) == AUDIO_ID && !pes) invalid++;
  97             else if (code == PRIVATE_STREAM_1  && !pes) invalid++;
  98         }
  99     }
 100
 101     if (vid + audio > invalid + 1) /* invalid VDR files nd short PES streams */
 102         score = AVPROBE_SCORE_EXTENSION / 2;
 103
 104 //     av_log(NULL, AV_LOG_ERROR, "vid:%d aud:%d sys:%d pspack:%d invalid:%d size:%d \n",
 105 //            vid, audio, sys, pspack, invalid, p->buf_size);
 106
 107     if (sys > invalid && sys * 9 <= pspack * 10)
 108         return (audio > 12 || vid > 3 || pspack > 2) ? AVPROBE_SCORE_EXTENSION + 2
 109                                                      : AVPROBE_SCORE_EXTENSION / 2 + (audio + vid + pspack > 1); // 1 more than mp3
 110     if (pspack > invalid && (priv1 + vid + audio) * 10 >= pspack * 9)
 111         return pspack > 2 ? AVPROBE_SCORE_EXTENSION + 2
 112                           : AVPROBE_SCORE_EXTENSION / 2; // 1 more than .mpg
 113     if ((!!vid ^ !!audio) && (audio > 4 || vid > 1) && !sys &&
 114         !pspack && p->buf_size > 2048 && vid + audio > invalid) /* PES stream */
 115         return (audio > 12 || vid > 6 + 2 * invalid) ? AVPROBE_SCORE_EXTENSION + 2
 116                                                      : AVPROBE_SCORE_EXTENSION / 2;
 117
 118     // 02-Penguin.flac has sys:0 priv1:0 pspack:0 vid:0 audio:1
 119     // mp3_misidentified_2.mp3 has sys:0 priv1:0 pspack:0 vid:0 audio:6
 120     // Have\ Yourself\ a\ Merry\ Little\ Christmas.mp3 0 0 0 5 0 1 len:21618
 121     return score;
 122 }
 123
 124 typedef struct MpegDemuxContext {
 125     AVClass *class;
 126     int32_t header_state;
 127     unsigned char psm_es_type[256];
 128     int sofdec;
 129     int dvd;
 130     int imkh_cctv;
 131 #if CONFIG_VOBSUB_DEMUXER
 132     AVFormatContext *sub_ctx;
 133     FFDemuxSubtitlesQueue q[32];
 134     char *sub_name;
 135 #endif
 136 } MpegDemuxContext;
 137
 138 static int mpegps_read_header(AVFormatContext *s)
 139 {
 140     MpegDemuxContext *m = s->priv_data;
 141     char buffer[7] = { 0 };
 142     int64_t last_pos = avio_tell(s->pb);
 143
 144     m->header_state = 0xff;
 145     s->ctx_flags   |= AVFMTCTX_NOHEADER;
 146
 147     avio_get_str(s->pb, 6, buffer, sizeof(buffer));
 148     if (!memcmp("IMKH", buffer, 4)) {
 149         m->imkh_cctv = 1;
 150     } else if (!memcmp("Sofdec", buffer, 6)) {
 151         m->sofdec = 1;
 152     } else
 153        avio_seek(s->pb, last_pos, SEEK_SET);
 154
 155     /* no need to do more */
 156     return 0;
 157 }
 158
 159 static int64_t get_pts(AVIOContext *pb, int c)
 160 {
 161     uint8_t buf[5];
 162     int ret;
 163
 164     buf[0] = c < 0 ? avio_r8(pb) : c;
 165     ret = avio_read(pb, buf + 1, 4);
 166     if (ret < 4)
 167         return AV_NOPTS_VALUE;
 168
 169     return ff_parse_pes_pts(buf);
 170 }
 171
 172 static int find_next_start_code(AVIOContext *pb, int *size_ptr,
 173                                 int32_t *header_state)
 174 {
 175     unsigned int state, v;
 176     int val, n;
 177
 178     state = *header_state;
 179     n     = *size_ptr;
 180     while (n > 0) {
 181         if (avio_feof(pb))
 182             break;
 183         v = avio_r8(pb);
 184         n--;
 185         if (state == 0x000001) {
 186             state = ((state << 8) | v) & 0xffffff;
 187             val   = state;
 188             goto found;
 189         }
 190         state = ((state << 8) | v) & 0xffffff;
 191     }
 192     val = -1;
 193
 194 found:
 195     *header_state = state;
 196     *size_ptr     = n;
 197     return val;
 198 }
 199
 200 /**
 201  * Extract stream types from a program stream map
 202  * According to ISO/IEC 13818-1 ('MPEG-2 Systems') table 2-35
 203  *
 204  * @return number of bytes occupied by PSM in the bitstream
 205  */
 206 static long mpegps_psm_parse(MpegDemuxContext *m, AVIOContext *pb)
 207 {
 208     int psm_length, ps_info_length, es_map_length;
 209
 210     psm_length = avio_rb16(pb);
 211     avio_r8(pb);
 212     avio_r8(pb);
 213     ps_info_length = avio_rb16(pb);
 214
 215     /* skip program_stream_info */
 216     avio_skip(pb, ps_info_length);
 217     /*es_map_length = */avio_rb16(pb);
 218     /* Ignore es_map_length, trust psm_length */
 219     es_map_length = psm_length - ps_info_length - 10;
 220
 221     /* at least one es available? */
 222     while (es_map_length >= 4) {
 223         unsigned char type      = avio_r8(pb);
 224         unsigned char es_id     = avio_r8(pb);
 225         uint16_t es_info_length = avio_rb16(pb);
 226
 227         /* remember mapping from stream id to stream type */
 228         m->psm_es_type[es_id] = type;
 229         /* skip program_stream_info */
 230         avio_skip(pb, es_info_length);
 231         es_map_length -= 4 + es_info_length;
 232     }
 233     avio_rb32(pb); /* crc32 */
 234     return 2 + psm_length;
 235 }
 236
 237 /* read the next PES header. Return its position in ppos
 238  * (if not NULL), and its start code, pts and dts.
 239  */
 240 static int mpegps_read_pes_header(AVFormatContext *s,
 241                                   int64_t *ppos, int *pstart_code,
 242                                   int64_t *ppts, int64_t *pdts)
 243 {
 244     MpegDemuxContext *m = s->priv_data;
 245     int len, size, startcode, c, flags, header_len;
 246     int pes_ext, ext2_len, id_ext, skip;
 247     int64_t pts, dts;
 248     int64_t last_sync = avio_tell(s->pb);
 249
 250 error_redo:
 251     avio_seek(s->pb, last_sync, SEEK_SET);
 252 redo:
 253     /* next start code (should be immediately after) */
 254     m->header_state = 0xff;
 255     size      = MAX_SYNC_SIZE;
 256     startcode = find_next_start_code(s->pb, &size, &m->header_state);
 257     last_sync = avio_tell(s->pb);
 258     if (startcode < 0) {
 259         if (avio_feof(s->pb))
 260             return AVERROR_EOF;
 261         // FIXME we should remember header_state
 262         return FFERROR_REDO;
 263     }
 264
 265     if (startcode == PACK_START_CODE)
 266         goto redo;
 267     if (startcode == SYSTEM_HEADER_START_CODE)
 268         goto redo;
 269     if (startcode == PADDING_STREAM) {
 270         avio_skip(s->pb, avio_rb16(s->pb));
 271         goto redo;
 272     }
 273     if (startcode == PRIVATE_STREAM_2) {
 274         if (!m->sofdec) {
 275             /* Need to detect whether this from a DVD or a 'Sofdec' stream */
 276             int len = avio_rb16(s->pb);
 277             int bytesread = 0;
 278             uint8_t *ps2buf = av_malloc(len);
 279
 280             if (ps2buf) {
 281                 bytesread = avio_read(s->pb, ps2buf, len);
 282
 283                 if (bytesread != len) {
 284                     avio_skip(s->pb, len - bytesread);
 285                 } else {
 286                     uint8_t *p = 0;
 287                     if (len >= 6)
 288                         p = memchr(ps2buf, 'S', len - 5);
 289
 290                     if (p)
 291                         m->sofdec = !memcmp(p+1, "ofdec", 5);
 292
 293                     m->sofdec -= !m->sofdec;
 294
 295                     if (m->sofdec < 0) {
 296                         if (len == 980  && ps2buf[0] == 0) {
 297                             /* PCI structure? */
 298                             uint32_t startpts = AV_RB32(ps2buf + 0x0d);
 299                             uint32_t endpts = AV_RB32(ps2buf + 0x11);
 300                             uint8_t hours = ((ps2buf[0x19] >> 4) * 10) + (ps2buf[0x19] & 0x0f);
 301                             uint8_t mins  = ((ps2buf[0x1a] >> 4) * 10) + (ps2buf[0x1a] & 0x0f);
 302                             uint8_t secs  = ((ps2buf[0x1b] >> 4) * 10) + (ps2buf[0x1b] & 0x0f);
 303
 304                             m->dvd = (hours <= 23 &&
 305                                       mins  <= 59 &&
 306                                       secs  <= 59 &&
 307                                       (ps2buf[0x19] & 0x0f) < 10 &&
 308                                       (ps2buf[0x1a] & 0x0f) < 10 &&
 309                                       (ps2buf[0x1b] & 0x0f) < 10 &&
 310                                       endpts >= startpts);
 311                         } else if (len == 1018 && ps2buf[0] == 1) {
 312                             /* DSI structure? */
 313                             uint8_t hours = ((ps2buf[0x1d] >> 4) * 10) + (ps2buf[0x1d] & 0x0f);
 314                             uint8_t mins  = ((ps2buf[0x1e] >> 4) * 10) + (ps2buf[0x1e] & 0x0f);
 315                             uint8_t secs  = ((ps2buf[0x1f] >> 4) * 10) + (ps2buf[0x1f] & 0x0f);
 316
 317                             m->dvd = (hours <= 23 &&
 318                                       mins  <= 59 &&
 319                                       secs  <= 59 &&
 320                                       (ps2buf[0x1d] & 0x0f) < 10 &&
 321                                       (ps2buf[0x1e] & 0x0f) < 10 &&
 322                                       (ps2buf[0x1f] & 0x0f) < 10);
 323                         }
 324                     }
 325                 }
 326
 327                 av_free(ps2buf);
 328
 329                 /* If this isn't a DVD packet or no memory
 330                  * could be allocated, just ignore it.
 331                  * If we did, move back to the start of the
 332                  * packet (plus 'length' field) */
 333                 if (!m->dvd || avio_skip(s->pb, -(len + 2)) < 0) {
 334                     /* Skip back failed.
 335                      * This packet will be lost but that can't be helped
 336                      * if we can't skip back
 337                      */
 338                     goto redo;
 339                 }
 340             } else {
 341                 /* No memory */
 342                 avio_skip(s->pb, len);
 343                 goto redo;
 344             }
 345         } else if (!m->dvd) {
 346             int len = avio_rb16(s->pb);
 347             avio_skip(s->pb, len);
 348             goto redo;
 349         }
 350     }
 351     if (startcode == PROGRAM_STREAM_MAP) {
 352         mpegps_psm_parse(m, s->pb);
 353         goto redo;
 354     }
 355
 356     /* find matching stream */
 357     if (!((startcode >= 0x1c0 && startcode <= 0x1df) ||
 358           (startcode >= 0x1e0 && startcode <= 0x1ef) ||
 359           (startcode == 0x1bd) ||
 360           (startcode == PRIVATE_STREAM_2) ||
 361           (startcode == 0x1fd)))
 362         goto redo;
 363     if (ppos) {
 364         *ppos = avio_tell(s->pb) - 4;
 365     }
 366     len = avio_rb16(s->pb);
 367     pts =
 368     dts = AV_NOPTS_VALUE;
 369     if (startcode != PRIVATE_STREAM_2)
 370     {
 371     /* stuffing */
 372     for (;;) {
 373         if (len < 1)
 374             goto error_redo;
 375         c = avio_r8(s->pb);
 376         len--;
 377         /* XXX: for MPEG-1, should test only bit 7 */
 378         if (c != 0xff)
 379             break;
 380     }
 381     if ((c & 0xc0) == 0x40) {
 382         /* buffer scale & size */
 383         avio_r8(s->pb);
 384         c    = avio_r8(s->pb);
 385         len -= 2;
 386     }
 387     if ((c & 0xe0) == 0x20) {
 388         dts  =
 389         pts  = get_pts(s->pb, c);
 390         len -= 4;
 391         if (c & 0x10) {
 392             dts  = get_pts(s->pb, -1);
 393             len -= 5;
 394         }
 395     } else if ((c & 0xc0) == 0x80) {
 396         /* mpeg 2 PES */
 397         flags      = avio_r8(s->pb);
 398         header_len = avio_r8(s->pb);
 399         len       -= 2;
 400         if (header_len > len)
 401             goto error_redo;
 402         len -= header_len;
 403         if (flags & 0x80) {
 404             dts         = pts = get_pts(s->pb, -1);
 405             header_len -= 5;
 406             if (flags & 0x40) {
 407                 dts         = get_pts(s->pb, -1);
 408                 header_len -= 5;
 409             }
 410         }
 411         if (flags & 0x3f && header_len == 0) {
 412             flags &= 0xC0;
 413             av_log(s, AV_LOG_WARNING, "Further flags set but no bytes left\n");
 414         }
 415         if (flags & 0x01) { /* PES extension */
 416             pes_ext = avio_r8(s->pb);
 417             header_len--;
 418             /* Skip PES private data, program packet sequence counter
 419              * and P-STD buffer */
 420             skip  = (pes_ext >> 4) & 0xb;
 421             skip += skip & 0x9;
 422             if (pes_ext & 0x40 || skip > header_len) {
 423                 av_log(s, AV_LOG_WARNING, "pes_ext %X is invalid\n", pes_ext);
 424                 pes_ext = skip = 0;
 425             }
 426             avio_skip(s->pb, skip);
 427             header_len -= skip;
 428
 429             if (pes_ext & 0x01) { /* PES extension 2 */
 430                 ext2_len = avio_r8(s->pb);
 431                 header_len--;
 432                 if ((ext2_len & 0x7f) > 0) {
 433                     id_ext = avio_r8(s->pb);
 434                     if ((id_ext & 0x80) == 0)
 435                         startcode = ((startcode & 0xff) << 8) | id_ext;
 436                     header_len--;
 437                 }
 438             }
 439         }
 440         if (header_len < 0)
 441             goto error_redo;
 442         avio_skip(s->pb, header_len);
 443     } else if (c != 0xf)
 444         goto redo;
 445     }
 446
 447     if (startcode == PRIVATE_STREAM_1) {
 448         startcode = avio_r8(s->pb);
 449         len--;
 450     }
 451     if (len < 0)
 452         goto error_redo;
 453     if (dts != AV_NOPTS_VALUE && ppos) {
 454         int i;
 455         for (i = 0; i < s->nb_streams; i++) {
 456             if (startcode == s->streams[i]->id &&
 457                 s->pb->seekable /* index useless on streams anyway */) {
 458                 ff_reduce_index(s, i);
 459                 av_add_index_entry(s->streams[i], *ppos, dts, 0, 0,
 460                                    AVINDEX_KEYFRAME /* FIXME keyframe? */);
 461             }
 462         }
 463     }
 464
 465     *pstart_code = startcode;
 466     *ppts        = pts;
 467     *pdts        = dts;
 468     return len;
 469 }
 470
 471 static int mpegps_read_packet(AVFormatContext *s,
 472                               AVPacket *pkt)
 473 {
 474     MpegDemuxContext *m = s->priv_data;
 475     AVStream *st;
 476     int len, startcode, i, es_type, ret;
 477     int lpcm_header_len = -1; //Init to suppress warning
 478     int request_probe= 0;
 479     enum AVCodecID codec_id = AV_CODEC_ID_NONE;
 480     enum AVMediaType type;
 481     int64_t pts, dts, dummy_pos; // dummy_pos is needed for the index building to work
 482
 483 redo:
 484     len = mpegps_read_pes_header(s, &dummy_pos, &startcode, &pts, &dts);
 485     if (len < 0)
 486         return len;
 487
 488     if (startcode >= 0x80 && startcode <= 0xcf) {
 489         if (len < 4)
 490             goto skip;
 491
 492         /* audio: skip header */
 493         avio_r8(s->pb);
 494         lpcm_header_len = avio_rb16(s->pb);
 495         len -= 3;
 496         if (startcode >= 0xb0 && startcode <= 0xbf) {
 497             /* MLP/TrueHD audio has a 4-byte header */
 498             avio_r8(s->pb);
 499             len--;
 500         }
 501     }
 502
 503     /* now find stream */
 504     for (i = 0; i < s->nb_streams; i++) {
 505         st = s->streams[i];
 506         if (st->id == startcode)
 507             goto found;
 508     }
 509
 510     es_type = m->psm_es_type[startcode & 0xff];
 511         if (es_type == STREAM_TYPE_VIDEO_MPEG1) {
 512             codec_id = AV_CODEC_ID_MPEG2VIDEO;
 513             type     = AVMEDIA_TYPE_VIDEO;
 514         } else if (es_type == STREAM_TYPE_VIDEO_MPEG2) {
 515             codec_id = AV_CODEC_ID_MPEG2VIDEO;
 516             type     = AVMEDIA_TYPE_VIDEO;
 517         } else if (es_type == STREAM_TYPE_AUDIO_MPEG1 ||
 518                    es_type == STREAM_TYPE_AUDIO_MPEG2) {
 519             codec_id = AV_CODEC_ID_MP3;
 520             type     = AVMEDIA_TYPE_AUDIO;
 521         } else if (es_type == STREAM_TYPE_AUDIO_AAC) {
 522             codec_id = AV_CODEC_ID_AAC;
 523             type     = AVMEDIA_TYPE_AUDIO;
 524         } else if (es_type == STREAM_TYPE_VIDEO_MPEG4) {
 525             codec_id = AV_CODEC_ID_MPEG4;
 526             type     = AVMEDIA_TYPE_VIDEO;
 527         } else if (es_type == STREAM_TYPE_VIDEO_H264) {
 528             codec_id = AV_CODEC_ID_H264;
 529             type     = AVMEDIA_TYPE_VIDEO;
 530         } else if (es_type == STREAM_TYPE_AUDIO_AC3) {
 531             codec_id = AV_CODEC_ID_AC3;
 532             type     = AVMEDIA_TYPE_AUDIO;
 533         } else if (m->imkh_cctv && es_type == 0x91) {
 534             codec_id = AV_CODEC_ID_PCM_MULAW;
 535             type     = AVMEDIA_TYPE_AUDIO;
 536     } else if (startcode >= 0x1e0 && startcode <= 0x1ef) {
 537         static const unsigned char avs_seqh[4] = { 0, 0, 1, 0xb0 };
 538         unsigned char buf[8];
 539
 540         avio_read(s->pb, buf, 8);
 541         avio_seek(s->pb, -8, SEEK_CUR);
 542         if (!memcmp(buf, avs_seqh, 4) && (buf[6] != 0 || buf[7] != 1))
 543             codec_id = AV_CODEC_ID_CAVS;
 544         else
 545             request_probe= 1;
 546         type = AVMEDIA_TYPE_VIDEO;
 547     } else if (startcode == PRIVATE_STREAM_2) {
 548         type = AVMEDIA_TYPE_DATA;
 549         codec_id = AV_CODEC_ID_DVD_NAV;
 550     } else if (startcode >= 0x1c0 && startcode <= 0x1df) {
 551         type     = AVMEDIA_TYPE_AUDIO;
 552         if (m->sofdec > 0) {
 553             codec_id = AV_CODEC_ID_ADPCM_ADX;
 554             // Auto-detect AC-3
 555             request_probe = 50;
 556         } else if (m->imkh_cctv && startcode == 0x1c0 && len > 80) {
 557             codec_id = AV_CODEC_ID_PCM_ALAW;
 558             request_probe = 50;
 559         } else {
 560             codec_id = AV_CODEC_ID_MP2;
 561             if (m->imkh_cctv)
 562                 request_probe = 25;
 563         }
 564     } else if (startcode >= 0x80 && startcode <= 0x87) {
 565         type     = AVMEDIA_TYPE_AUDIO;
 566         codec_id = AV_CODEC_ID_AC3;
 567     } else if ((startcode >= 0x88 && startcode <= 0x8f) ||
 568                (startcode >= 0x98 && startcode <= 0x9f)) {
 569         /* 0x90 - 0x97 is reserved for SDDS in DVD specs */
 570         type     = AVMEDIA_TYPE_AUDIO;
 571         codec_id = AV_CODEC_ID_DTS;
 572     } else if (startcode >= 0xa0 && startcode <= 0xaf) {
 573         type     = AVMEDIA_TYPE_AUDIO;
 574         if (lpcm_header_len == 6 || startcode == 0xa1) {
 575             codec_id = AV_CODEC_ID_MLP;
 576         } else {
 577             codec_id = AV_CODEC_ID_PCM_DVD;
 578         }
 579     } else if (startcode >= 0xb0 && startcode <= 0xbf) {
 580         type     = AVMEDIA_TYPE_AUDIO;
 581         codec_id = AV_CODEC_ID_TRUEHD;
 582     } else if (startcode >= 0xc0 && startcode <= 0xcf) {
 583         /* Used for both AC-3 and E-AC-3 in EVOB files */
 584         type     = AVMEDIA_TYPE_AUDIO;
 585         codec_id = AV_CODEC_ID_AC3;
 586     } else if (startcode >= 0x20 && startcode <= 0x3f) {
 587         type     = AVMEDIA_TYPE_SUBTITLE;
 588         codec_id = AV_CODEC_ID_DVD_SUBTITLE;
 589     } else if (startcode >= 0xfd55 && startcode <= 0xfd5f) {
 590         type     = AVMEDIA_TYPE_VIDEO;
 591         codec_id = AV_CODEC_ID_VC1;
 592     } else {
 593 skip:
 594         /* skip packet */
 595         avio_skip(s->pb, len);
 596         goto redo;
 597     }
 598     /* no stream found: add a new stream */
 599     st = avformat_new_stream(s, NULL);
 600     if (!st)
 601         goto skip;
 602     st->id                = startcode;
 603     st->codecpar->codec_type = type;
 604     st->codecpar->codec_id   = codec_id;
 605     if (   st->codecpar->codec_id == AV_CODEC_ID_PCM_MULAW
 606         || st->codecpar->codec_id == AV_CODEC_ID_PCM_ALAW) {
 607         st->codecpar->channels = 1;
 608         st->codecpar->channel_layout = AV_CH_LAYOUT_MONO;
 609         st->codecpar->sample_rate = 8000;
 610     }
 611     st->request_probe     = request_probe;
 612     st->need_parsing      = AVSTREAM_PARSE_FULL;
 613
 614 found:
 615     if (st->discard >= AVDISCARD_ALL)
 616         goto skip;
 617     if (startcode >= 0xa0 && startcode <= 0xaf) {
 618       if (st->codecpar->codec_id == AV_CODEC_ID_MLP) {
 619             if (len < 6)
 620                 goto skip;
 621             avio_skip(s->pb, 6);
 622             len -=6;
 623       }
 624     }
 625     ret = av_get_packet(s->pb, pkt, len);
 626
 627     pkt->pts          = pts;
 628     pkt->dts          = dts;
 629     pkt->pos          = dummy_pos;
 630     pkt->stream_index = st->index;
 631
 632     if (s->debug & FF_FDEBUG_TS)
 633         av_log(s, AV_LOG_TRACE, "%d: pts=%0.3f dts=%0.3f size=%d\n",
 634             pkt->stream_index, pkt->pts / 90000.0, pkt->dts / 90000.0,
 635             pkt->size);
 636
 637     return (ret < 0) ? ret : 0;
 638 }
 639
 640 static int64_t mpegps_read_dts(AVFormatContext *s, int stream_index,
 641                                int64_t *ppos, int64_t pos_limit)
 642 {
 643     int len, startcode;
 644     int64_t pos, pts, dts;
 645
 646     pos = *ppos;
 647     if (avio_seek(s->pb, pos, SEEK_SET) < 0)
 648         return AV_NOPTS_VALUE;
 649
 650     for (;;) {
 651         len = mpegps_read_pes_header(s, &pos, &startcode, &pts, &dts);
 652         if (len < 0) {
 653             if (s->debug & FF_FDEBUG_TS)
 654                 av_log(s, AV_LOG_TRACE, "none (ret=%d)\n", len);
 655             return AV_NOPTS_VALUE;
 656         }
 657         if (startcode == s->streams[stream_index]->id &&
 658             dts != AV_NOPTS_VALUE) {
 659             break;
 660         }
 661         avio_skip(s->pb, len);
 662     }
 663     if (s->debug & FF_FDEBUG_TS)
 664         av_log(s, AV_LOG_TRACE, "pos=0x%"PRIx64" dts=0x%"PRIx64" %0.3f\n",
 665             pos, dts, dts / 90000.0);
 666     *ppos = pos;
 667     return dts;
 668 }
 669
 670 AVInputFormat ff_mpegps_demuxer = {
 671     .name           = "mpeg",
 672     .long_name      = NULL_IF_CONFIG_SMALL("MPEG-PS (MPEG-2 Program Stream)"),
 673     .priv_data_size = sizeof(MpegDemuxContext),
 674     .read_probe     = mpegps_probe,
 675     .read_header    = mpegps_read_header,
 676     .read_packet    = mpegps_read_packet,
 677     .read_timestamp = mpegps_read_dts,
 678     .flags          = AVFMT_SHOW_IDS | AVFMT_TS_DISCONT,
 679 };
 680
 681 #if CONFIG_VOBSUB_DEMUXER
 682
 683 #define REF_STRING "# VobSub index file,"
 684 #define MAX_LINE_SIZE 2048
 685
 686 static int vobsub_probe(AVProbeData *p)
 687 {
 688     if (!strncmp(p->buf, REF_STRING, sizeof(REF_STRING) - 1))
 689         return AVPROBE_SCORE_MAX;
 690     return 0;
 691 }
 692
 693 static int vobsub_read_header(AVFormatContext *s)
 694 {
 695     int i, ret = 0, header_parsed = 0, langidx = 0;
 696     MpegDemuxContext *vobsub = s->priv_data;
 697     size_t fname_len;
 698     char *header_str;
 699     AVBPrint header;
 700     int64_t delay = 0;
 701     AVStream *st = NULL;
 702     int stream_id = -1;
 703     char id[64] = {0};
 704     char alt[MAX_LINE_SIZE] = {0};
 705     AVInputFormat *iformat;
 706
 707     if (!vobsub->sub_name) {
 708         char *ext;
 709         vobsub->sub_name = av_strdup(s->filename);
 710         if (!vobsub->sub_name) {
 711             ret = AVERROR(ENOMEM);
 712             goto end;
 713         }
 714
 715         fname_len = strlen(vobsub->sub_name);
 716         ext = vobsub->sub_name - 3 + fname_len;
 717         if (fname_len < 4 || *(ext - 1) != '.') {
 718             av_log(s, AV_LOG_ERROR, "The input index filename is too short "
 719                    "to guess the associated .SUB file\n");
 720             ret = AVERROR_INVALIDDATA;
 721             goto end;
 722         }
 723         memcpy(ext, !strncmp(ext, "IDX", 3) ? "SUB" : "sub", 3);
 724         av_log(s, AV_LOG_VERBOSE, "IDX/SUB: %s -> %s\n", s->filename, vobsub->sub_name);
 725     }
 726
 727     if (!(iformat = av_find_input_format("mpeg"))) {
 728         ret = AVERROR_DEMUXER_NOT_FOUND;
 729         goto end;
 730     }
 731
 732     vobsub->sub_ctx = avformat_alloc_context();
 733     if (!vobsub->sub_ctx) {
 734         ret = AVERROR(ENOMEM);
 735         goto end;
 736     }
 737
 738     if ((ret = ff_copy_whiteblacklists(vobsub->sub_ctx, s)) < 0)
 739         goto end;
 740
 741     ret = avformat_open_input(&vobsub->sub_ctx, vobsub->sub_name, iformat, NULL);
 742     if (ret < 0) {
 743         av_log(s, AV_LOG_ERROR, "Unable to open %s as MPEG subtitles\n", vobsub->sub_name);
 744         goto end;
 745     }
 746
 747     av_bprint_init(&header, 0, AV_BPRINT_SIZE_UNLIMITED);
 748     while (!avio_feof(s->pb)) {
 749         char line[MAX_LINE_SIZE];
 750         int len = ff_get_line(s->pb, line, sizeof(line));
 751
 752         if (!len)
 753             break;
 754
 755         line[strcspn(line, "\r\n")] = 0;
 756
 757         if (!strncmp(line, "id:", 3)) {
 758             if (sscanf(line, "id: %63[^,], index: %u", id, &stream_id) != 2) {
 759                 av_log(s, AV_LOG_WARNING, "Unable to parse index line '%s', "
 760                        "assuming 'id: und, index: 0'\n", line);
 761                 strcpy(id, "und");
 762                 stream_id = 0;
 763             }
 764
 765             if (stream_id >= FF_ARRAY_ELEMS(vobsub->q)) {
 766                 av_log(s, AV_LOG_ERROR, "Maximum number of subtitles streams reached\n");
 767                 ret = AVERROR(EINVAL);
 768                 goto end;
 769             }
 770
 771             header_parsed = 1;
 772             alt[0] = '\0';
 773             /* We do not create the stream immediately to avoid adding empty
 774              * streams. See the following timestamp entry. */
 775
 776             av_log(s, AV_LOG_DEBUG, "IDX stream[%d] id=%s\n", stream_id, id);
 777
 778         } else if (!strncmp(line, "timestamp:", 10)) {
 779             AVPacket *sub;
 780             int hh, mm, ss, ms;
 781             int64_t pos, timestamp;
 782             const char *p = line + 10;
 783
 784             if (stream_id == -1) {
 785                 av_log(s, AV_LOG_ERROR, "Timestamp declared before any stream\n");
 786                 ret = AVERROR_INVALIDDATA;
 787                 goto end;
 788             }
 789
 790             if (!st || st->id != stream_id) {
 791                 st = avformat_new_stream(s, NULL);
 792                 if (!st) {
 793                     ret = AVERROR(ENOMEM);
 794                     goto end;
 795                 }
 796                 st->id = stream_id;
 797                 st->codecpar->codec_type = AVMEDIA_TYPE_SUBTITLE;
 798                 st->codecpar->codec_id   = AV_CODEC_ID_DVD_SUBTITLE;
 799                 avpriv_set_pts_info(st, 64, 1, 1000);
 800                 av_dict_set(&st->metadata, "language", id, 0);
 801                 if (alt[0])
 802                     av_dict_set(&st->metadata, "title", alt, 0);
 803             }
 804
 805             if (sscanf(p, "%02d:%02d:%02d:%03d, filepos: %"SCNx64,
 806                        &hh, &mm, &ss, &ms, &pos) != 5) {
 807                 av_log(s, AV_LOG_ERROR, "Unable to parse timestamp line '%s', "
 808                        "abort parsing\n", line);
 809                 ret = AVERROR_INVALIDDATA;
 810                 goto end;
 811             }
 812             timestamp = (hh*3600LL + mm*60LL + ss) * 1000LL + ms + delay;
 813             timestamp = av_rescale_q(timestamp, av_make_q(1, 1000), st->time_base);
 814
 815             sub = ff_subtitles_queue_insert(&vobsub->q[s->nb_streams - 1], "", 0, 0);
 816             if (!sub) {
 817                 ret = AVERROR(ENOMEM);
 818                 goto end;
 819             }
 820             sub->pos = pos;
 821             sub->pts = timestamp;
 822             sub->stream_index = s->nb_streams - 1;
 823
 824         } else if (!strncmp(line, "alt:", 4)) {
 825             const char *p = line + 4;
 826
 827             while (*p == ' ')
 828                 p++;
 829             av_log(s, AV_LOG_DEBUG, "IDX stream[%d] name=%s\n", stream_id, p);
 830             av_strlcpy(alt, p, sizeof(alt));
 831             header_parsed = 1;
 832
 833         } else if (!strncmp(line, "delay:", 6)) {
 834             int sign = 1, hh = 0, mm = 0, ss = 0, ms = 0;
 835             const char *p = line + 6;
 836
 837             while (*p == ' ')
 838                 p++;
 839             if (*p == '-' || *p == '+') {
 840                 sign = *p == '-' ? -1 : 1;
 841                 p++;
 842             }
 843             sscanf(p, "%d:%d:%d:%d", &hh, &mm, &ss, &ms);
 844             delay = ((hh*3600LL + mm*60LL + ss) * 1000LL + ms) * sign;
 845
 846         } else if (!strncmp(line, "langidx:", 8)) {
 847             const char *p = line + 8;
 848
 849             if (sscanf(p, "%d", &langidx) != 1)
 850                 av_log(s, AV_LOG_ERROR, "Invalid langidx specified\n");
 851
 852         } else if (!header_parsed) {
 853             if (line[0] && line[0] != '#')
 854                 av_bprintf(&header, "%s\n", line);
 855         }
 856     }
 857
 858     if (langidx < s->nb_streams)
 859         s->streams[langidx]->disposition |= AV_DISPOSITION_DEFAULT;
 860
 861     for (i = 0; i < s->nb_streams; i++) {
 862         vobsub->q[i].sort = SUB_SORT_POS_TS;
 863         vobsub->q[i].keep_duplicates = 1;
 864         ff_subtitles_queue_finalize(s, &vobsub->q[i]);
 865     }
 866
 867     if (!av_bprint_is_complete(&header)) {
 868         av_bprint_finalize(&header, NULL);
 869         ret = AVERROR(ENOMEM);
 870         goto end;
 871     }
 872     av_bprint_finalize(&header, &header_str);
 873     for (i = 0; i < s->nb_streams; i++) {
 874         AVStream *sub_st = s->streams[i];
 875         sub_st->codecpar->extradata      = av_strdup(header_str);
 876         sub_st->codecpar->extradata_size = header.len;
 877     }
 878     av_free(header_str);
 879
 880 end:
 881     return ret;
 882 }
 883
 884 static int vobsub_read_packet(AVFormatContext *s, AVPacket *pkt)
 885 {
 886     MpegDemuxContext *vobsub = s->priv_data;
 887     FFDemuxSubtitlesQueue *q;
 888     AVIOContext *pb = vobsub->sub_ctx->pb;
 889     int ret, psize, total_read = 0, i;
 890     AVPacket idx_pkt;
 891
 892     int64_t min_ts = INT64_MAX;
 893     int sid = 0;
 894     for (i = 0; i < s->nb_streams; i++) {
 895         FFDemuxSubtitlesQueue *tmpq = &vobsub->q[i];
 896         int64_t ts;
 897         av_assert0(tmpq->nb_subs);
 898         ts = tmpq->subs[tmpq->current_sub_idx].pts;
 899         if (ts < min_ts) {
 900             min_ts = ts;
 901             sid = i;
 902         }
 903     }
 904     q = &vobsub->q[sid];
 905     ret = ff_subtitles_queue_read_packet(q, &idx_pkt);
 906     if (ret < 0)
 907         return ret;
 908
 909     /* compute maximum packet size using the next packet position. This is
 910      * useful when the len in the header is non-sense */
 911     if (q->current_sub_idx < q->nb_subs) {
 912         psize = q->subs[q->current_sub_idx].pos - idx_pkt.pos;
 913     } else {
 914         int64_t fsize = avio_size(pb);
 915         psize = fsize < 0 ? 0xffff : fsize - idx_pkt.pos;
 916     }
 917
 918     avio_seek(pb, idx_pkt.pos, SEEK_SET);
 919
 920     av_init_packet(pkt);
 921     pkt->size = 0;
 922     pkt->data = NULL;
 923
 924     do {
 925         int n, to_read, startcode;
 926         int64_t pts, dts;
 927         int64_t old_pos = avio_tell(pb), new_pos;
 928         int pkt_size;
 929
 930         ret = mpegps_read_pes_header(vobsub->sub_ctx, NULL, &startcode, &pts, &dts);
 931         if (ret < 0) {
 932             if (pkt->size) // raise packet even if incomplete
 933                 break;
 934             goto fail;
 935         }
 936         to_read = ret & 0xffff;
 937         new_pos = avio_tell(pb);
 938         pkt_size = ret + (new_pos - old_pos);
 939
 940         /* this prevents reads above the current packet */
 941         if (total_read + pkt_size > psize)
 942             break;
 943         total_read += pkt_size;
 944
 945         /* the current chunk doesn't match the stream index (unlikely) */
 946         if ((startcode & 0x1f) != s->streams[idx_pkt.stream_index]->id)
 947             break;
 948
 949         ret = av_grow_packet(pkt, to_read);
 950         if (ret < 0)
 951             goto fail;
 952
 953         n = avio_read(pb, pkt->data + (pkt->size - to_read), to_read);
 954         if (n < to_read)
 955             pkt->size -= to_read - n;
 956     } while (total_read < psize);
 957
 958     pkt->pts = pkt->dts = idx_pkt.pts;
 959     pkt->pos = idx_pkt.pos;
 960     pkt->stream_index = idx_pkt.stream_index;
 961
 962     av_packet_unref(&idx_pkt);
 963     return 0;
 964
 965 fail:
 966     av_packet_unref(pkt);
 967     av_packet_unref(&idx_pkt);
 968     return ret;
 969 }
 970
 971 static int vobsub_read_seek(AVFormatContext *s, int stream_index,
 972                             int64_t min_ts, int64_t ts, int64_t max_ts, int flags)
 973 {
 974     MpegDemuxContext *vobsub = s->priv_data;
 975
 976     /* Rescale requested timestamps based on the first stream (timebase is the
 977      * same for all subtitles stream within a .idx/.sub). Rescaling is done just
 978      * like in avformat_seek_file(). */
 979     if (stream_index == -1 && s->nb_streams != 1) {
 980         int i, ret = 0;
 981         AVRational time_base = s->streams[0]->time_base;
 982         ts = av_rescale_q(ts, AV_TIME_BASE_Q, time_base);
 983         min_ts = av_rescale_rnd(min_ts, time_base.den,
 984                                 time_base.num * (int64_t)AV_TIME_BASE,
 985                                 AV_ROUND_UP   | AV_ROUND_PASS_MINMAX);
 986         max_ts = av_rescale_rnd(max_ts, time_base.den,
 987                                 time_base.num * (int64_t)AV_TIME_BASE,
 988                                 AV_ROUND_DOWN | AV_ROUND_PASS_MINMAX);
 989         for (i = 0; i < s->nb_streams; i++) {
 990             int r = ff_subtitles_queue_seek(&vobsub->q[i], s, stream_index,
 991                                             min_ts, ts, max_ts, flags);
 992             if (r < 0)
 993                 ret = r;
 994         }
 995         return ret;
 996     }
 997
 998     if (stream_index == -1) // only 1 stream
 999         stream_index = 0;
1000     return ff_subtitles_queue_seek(&vobsub->q[stream_index], s, stream_index,
1001                                    min_ts, ts, max_ts, flags);
1002 }
1003
1004 static int vobsub_read_close(AVFormatContext *s)
1005 {
1006     int i;
1007     MpegDemuxContext *vobsub = s->priv_data;
1008
1009     for (i = 0; i < s->nb_streams; i++)
1010         ff_subtitles_queue_clean(&vobsub->q[i]);
1011     if (vobsub->sub_ctx)
1012         avformat_close_input(&vobsub->sub_ctx);
1013     return 0;
1014 }
1015
1016 static const AVOption options[] = {
1017     { "sub_name", "URI for .sub file", offsetof(MpegDemuxContext, sub_name), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, AV_OPT_FLAG_DECODING_PARAM },
1018     { NULL }
1019 };
1020
1021 static const AVClass vobsub_demuxer_class = {
1022     .class_name = "vobsub",
1023     .item_name  = av_default_item_name,
1024     .option     = options,
1025     .version    = LIBAVUTIL_VERSION_INT,
1026 };
1027
1028 AVInputFormat ff_vobsub_demuxer = {
1029     .name           = "vobsub",
1030     .long_name      = NULL_IF_CONFIG_SMALL("VobSub subtitle format"),
1031     .priv_data_size = sizeof(MpegDemuxContext),
1032     .read_probe     = vobsub_probe,
1033     .read_header    = vobsub_read_header,
1034     .read_packet    = vobsub_read_packet,
1035     .read_seek2     = vobsub_read_seek,
1036     .read_close     = vobsub_read_close,
1037     .flags          = AVFMT_SHOW_IDS,
1038     .extensions     = "idx",
1039     .priv_class     = &vobsub_demuxer_class,
1040 };
1041 #endif