lib/dvb/pvrparse.cpp

   1 #include <lib/dvb/pvrparse.h>
   2 #include <lib/base/eerror.h>
   3 #include <byteswap.h>
   4
   5 #ifndef BYTE_ORDER
   6 #error no byte order defined!
   7 #endif
   8
   9 int eMPEGStreamInformation::save(const char *filename)
  10 {
  11         FILE *f = fopen(filename, "wb");
  12         if (!f)
  13                 return -1;
  14
  15         for (std::map<off_t, pts_t>::const_iterator i(m_access_points.begin()); i != m_access_points.end(); ++i)
  16         {
  17                 unsigned long long d[2];
  18 #if BYTE_ORDER == BIG_ENDIAN
  19                 d[0] = i->first;
  20                 d[1] = i->second;
  21 #else
  22                 d[0] = bswap_64(i->first);
  23                 d[1] = bswap_64(i->second);
  24 #endif
  25                 fwrite(d, sizeof(d), 1, f);
  26         }
  27         fclose(f);
  28
  29         return 0;
  30 }
  31
  32 int eMPEGStreamInformation::load(const char *filename)
  33 {
  34         FILE *f = fopen(filename, "rb");
  35         if (!f)
  36                 return -1;
  37         m_access_points.clear();
  38         m_pts_to_offset.clear();
  39         while (1)
  40         {
  41                 unsigned long long d[2];
  42                 if (fread(d, sizeof(d), 1, f) < 1)
  43                         break;
  44
  45 #if BYTE_ORDER == LITTLE_ENDIAN
  46                 d[0] = bswap_64(d[0]);
  47                 d[1] = bswap_64(d[1]);
  48 #endif
  49                 m_access_points[d[0]] = d[1];
  50                 m_pts_to_offset.insert(std::pair<pts_t,off_t>(d[1], d[0]));
  51         }
  52         fclose(f);
  53         fixupDiscontinuties();
  54         return 0;
  55 }
  56
  57 bool eMPEGStreamInformation::empty()
  58 {
  59         return m_access_points.empty();
  60 }
  61
  62 void eMPEGStreamInformation::fixupDiscontinuties()
  63 {
  64         m_timestamp_deltas.clear();
  65         if (!m_access_points.size())
  66                 return;
  67
  68 //      eDebug("Fixing discontinuities ...");
  69
  70                         /* if we have no delta at the beginning, extrapolate it */
  71         if ((m_access_points.find(0) == m_access_points.end()) && (m_access_points.size() > 1))
  72         {
  73                 std::map<off_t,pts_t>::const_iterator second = m_access_points.begin();
  74                 std::map<off_t,pts_t>::const_iterator first  = second++;
  75                 if (first->first < second->first) /* i.e., not equal or broken */
  76                 {
  77                         off_t diff = second->first - first->first;
  78                         pts_t tdiff = second->second - first->second;
  79                         tdiff *= first->first;
  80                         tdiff /= diff;
  81                         m_timestamp_deltas[0] = first->second - tdiff;
  82 //                      eDebug("first delta is %08llx", first->second - tdiff);
  83                 }
  84         }
  85
  86         if (m_timestamp_deltas.empty())
  87                 m_timestamp_deltas[m_access_points.begin()->first] = m_access_points.begin()->second;
  88
  89         pts_t currentDelta = m_timestamp_deltas.begin()->second, lastpts_t = 0;
  90         for (std::map<off_t,pts_t>::const_iterator i(m_access_points.begin()); i != m_access_points.end(); ++i)
  91         {
  92                 pts_t current = i->second - currentDelta;
  93                 pts_t diff = current - lastpts_t;
  94
  95                 if (llabs(diff) > (90000*5)) // 5sec diff
  96                 {
  97 //                      eDebug("%llx < %llx, have discont. new timestamp is %llx (diff is %llx)!", current, lastpts_t, i->second, diff);
  98                         currentDelta = i->second - lastpts_t; /* FIXME: should be the extrapolated new timestamp, based on the current rate */
  99 //                      eDebug("current delta now %llx, making current to %llx", currentDelta, i->second - currentDelta);
 100                         m_timestamp_deltas[i->first] = currentDelta;
 101                 }
 102                 lastpts_t = i->second - currentDelta;
 103         }
 104
 105
 106 //      eDebug("ok, found %d disconts.", m_timestamp_deltas.size());
 107
 108 #if 0
 109         for (off_t x=0x25807E34ULL; x < 0x25B3CF70; x+= 100000)
 110         {
 111                 off_t o = x;
 112                 pts_t p;
 113                 int r = getPTS(o, p);
 114                 eDebug("%08llx -> %08llx | %08llx, %d, %08llx %08llx", x, getDelta(x), getInterpolated(x), r, o, p);
 115         }
 116 #endif
 117 }
 118
 119 pts_t eMPEGStreamInformation::getDelta(off_t offset)
 120 {
 121         if (!m_timestamp_deltas.size())
 122                 return 0;
 123         std::map<off_t,pts_t>::iterator i = m_timestamp_deltas.upper_bound(offset);
 124
 125                 /* i can be the first when you query for something before the first PTS */
 126         if (i != m_timestamp_deltas.begin())
 127                 --i;
 128
 129         return i->second;
 130 }
 131
 132 int eMPEGStreamInformation::fixupPTS(const off_t &offset, pts_t &ts)
 133 {
 134         if (!m_timestamp_deltas.size())
 135                 return -1;
 136
 137         std::multimap<pts_t, off_t>::const_iterator
 138                 l = m_pts_to_offset.upper_bound(ts - 60 * 90000),
 139                 u = m_pts_to_offset.upper_bound(ts + 60 * 90000),
 140                 nearest = m_pts_to_offset.end();
 141
 142         while (l != u)
 143         {
 144                 if ((nearest == m_pts_to_offset.end()) || (llabs(l->first - ts) < llabs(nearest->first - ts)))
 145                         nearest = l;
 146                 ++l;
 147         }
 148         if (nearest == m_pts_to_offset.end())
 149                 return 1;
 150
 151         ts -= getDelta(nearest->second);
 152
 153         return 0;
 154 }
 155
 156 int eMPEGStreamInformation::getPTS(off_t &offset, pts_t &pts)
 157 {
 158         std::map<off_t,pts_t>::iterator before = m_access_points.lower_bound(offset);
 159
 160                 /* usually, we prefer the AP before the given offset. however if there is none, we take any. */
 161         if (before != m_access_points.begin())
 162                 --before;
 163
 164         if (before == m_access_points.end())
 165         {
 166                 pts = 0;
 167                 return -1;
 168         }
 169
 170         offset = before->first;
 171         pts = before->second - getDelta(offset);
 172
 173         return 0;
 174 }
 175
 176 pts_t eMPEGStreamInformation::getInterpolated(off_t offset)
 177 {
 178                 /* get the PTS values before and after the offset. */
 179         std::map<off_t,pts_t>::iterator before, after;
 180         after = m_access_points.upper_bound(offset);
 181         before = after;
 182
 183         if (before != m_access_points.begin())
 184                 --before;
 185         else    /* we query before the first known timestamp ... FIXME */
 186                 return 0;
 187
 188                 /* empty... */
 189         if (before == m_access_points.end())
 190                 return 0;
 191
 192                 /* if after == end, then we need to extrapolate ... FIXME */
 193         if ((before->first == offset) || (after == m_access_points.end()))
 194                 return before->second - getDelta(offset);
 195
 196         pts_t before_ts = before->second - getDelta(before->first);
 197         pts_t after_ts = after->second - getDelta(after->first);
 198
 199 //      eDebug("%08llx .. ? .. %08llx", before_ts, after_ts);
 200 //      eDebug("%08llx .. %08llx .. %08llx", before->first, offset, after->first);
 201
 202         pts_t diff = after_ts - before_ts;
 203         off_t diff_off = after->first - before->first;
 204
 205         diff = (offset - before->first) * diff / diff_off;
 206 //      eDebug("%08llx .. %08llx .. %08llx", before_ts, before_ts + diff, after_ts);
 207         return before_ts + diff;
 208 }
 209
 210 off_t eMPEGStreamInformation::getAccessPoint(pts_t ts, int marg)
 211 {
 212                 /* FIXME: more efficient implementation */
 213         off_t last = 0;
 214         off_t last2 = 0;
 215         pts_t lastc = 0;
 216         for (std::map<off_t, pts_t>::const_iterator i(m_access_points.begin()); i != m_access_points.end(); ++i)
 217         {
 218                 pts_t delta = getDelta(i->first);
 219                 pts_t c = i->second - delta;
 220                 if (c > ts) {
 221                         if (marg > 0)
 222                                 return (last + i->first)/376*188;
 223                         else if (marg < 0)
 224                                 return (last + last2)/376*188;
 225                         else
 226                                 return last;
 227                 }
 228                 lastc = c;
 229                 last2 = last;
 230                 last = i->first;
 231         }
 232         if (marg < 0)
 233                 return (last + last2)/376*188;
 234         else
 235                 return last;
 236 }
 237
 238 int eMPEGStreamInformation::getNextAccessPoint(pts_t &ts, const pts_t &start, int direction)
 239 {
 240         off_t offset = getAccessPoint(start);
 241         pts_t c1, c2;
 242         std::map<off_t, pts_t>::const_iterator i = m_access_points.find(offset);
 243         if (i == m_access_points.end())
 244         {
 245                 eDebug("getNextAccessPoint: initial AP not found");
 246                 return -1;
 247         }
 248         c1 = i->second - getDelta(i->first);
 249         while (direction)
 250         {
 251                 if (direction > 0)
 252                 {
 253                         if (i == m_access_points.end())
 254                                 return -1;
 255                         ++i;
 256                         c2 = i->second - getDelta(i->first);
 257                         if (c1 == c2) { // Discontinuity
 258                                 ++i;
 259                                 c2 = i->second - getDelta(i->first);
 260                         }
 261                         c1 = c2;
 262                         direction--;
 263                 }
 264                 if (direction < 0)
 265                 {
 266                         if (i == m_access_points.begin())
 267                         {
 268                                 eDebug("at start");
 269                                 return -1;
 270                         }
 271                         --i;
 272                         c2 = i->second - getDelta(i->first);
 273                         if (c1 == c2) { // Discontinuity
 274                                 --i;
 275                                 c2 = i->second - getDelta(i->first);
 276                         }
 277                         c1 = c2;
 278                         direction++;
 279                 }
 280         }
 281         ts = i->second - getDelta(i->first);
 282         eDebug("fine, at %llx - %llx = %llx", ts, i->second, getDelta(i->first));
 283         eDebug("fine, at %lld - %lld = %lld", ts, i->second, getDelta(i->first));
 284         return 0;
 285 }
 286
 287 eMPEGStreamParserTS::eMPEGStreamParserTS(eMPEGStreamInformation &streaminfo): m_streaminfo(streaminfo), m_pktptr(0), m_pid(-1), m_need_next_packet(0), m_skip(0)
 288 {
 289 }
 290
 291 int eMPEGStreamParserTS::processPacket(const unsigned char *pkt, off_t offset)
 292 {
 293         if (!wantPacket(pkt))
 294                 eWarning("something's wrong.");
 295
 296         const unsigned char *end = pkt + 188;
 297
 298         if (!(pkt[3] & 0x10))
 299         {
 300                 eWarning("[TSPARSE] PUSI set but no payload.");
 301                 return 0;
 302         }
 303
 304         if (pkt[3] & 0x20) // adaption field present?
 305                 pkt += pkt[4] + 4 + 1;  /* skip adaption field and header */
 306         else
 307                 pkt += 4; /* skip header */
 308
 309         if (pkt > end)
 310         {
 311                 eWarning("[TSPARSE] dropping huge adaption field");
 312                 return 0;
 313         }
 314
 315                 // ok, we now have the start of the payload, aligned with the PES packet start.
 316         if (pkt[0] || pkt[1] || (pkt[2] != 1))
 317         {
 318                 eWarning("broken startcode");
 319                 return 0;
 320         }
 321
 322
 323         pts_t pts = 0;
 324         int ptsvalid = 0;
 325
 326         if (pkt[7] & 0x80) // PTS present?
 327         {
 328                 pts  = ((unsigned long long)(pkt[ 9]&0xE))  << 29;
 329                 pts |= ((unsigned long long)(pkt[10]&0xFF)) << 22;
 330                 pts |= ((unsigned long long)(pkt[11]&0xFE)) << 14;
 331                 pts |= ((unsigned long long)(pkt[12]&0xFF)) << 7;
 332                 pts |= ((unsigned long long)(pkt[13]&0xFE)) >> 1;
 333                 ptsvalid = 1;
 334
 335 #if 0
 336                 int sec = pts / 90000;
 337                 int frm = pts % 90000;
 338                 int min = sec / 60;
 339                 sec %= 60;
 340                 int hr = min / 60;
 341                 min %= 60;
 342                 int d = hr / 24;
 343                 hr %= 24;
 344
 345                 eDebug("pts: %016llx %d:%02d:%02d:%02d:%05d", pts, d, hr, min, sec, frm);
 346 #endif
 347         }
 348
 349                 /* advance to payload */
 350         pkt += pkt[8] + 9;
 351
 352                 /* sometimes, there are zeros before the startcode. */
 353         while (pkt < (end-4))
 354                 if (pkt[0] || pkt[1] || pkt[2])
 355                         break;
 356                 else
 357                         pkt++;
 358
 359                 /* if startcode found */
 360 //      eDebug("%02x %02x %02x %02x", pkt[0], pkt[1], pkt[2], pkt[3]);
 361         if (!(pkt[0] || pkt[1] || (pkt[2] != 1)))
 362         {
 363                 if (pkt[3] == 0xb3) /* sequence header */
 364                 {
 365                         if (ptsvalid)
 366                         {
 367                                 m_streaminfo.m_access_points[offset] = pts;
 368                                 eDebug("Sequence header at %llx, pts %llx", offset, pts);
 369                         } else
 370                                 eDebug("Sequence header but no valid PTS value.");
 371                 }
 372
 373                 if (pkt[3] == 0x09 &&   /* MPEG4 AVC unit access delimiter */
 374                          (pkt[4] >> 5) == 0) /* and I-frame */
 375                 {
 376                         if (ptsvalid)
 377                         {
 378                                 m_streaminfo.m_access_points[offset] = pts;
 379                                 eDebug("MPEG4 AVC UAD at %llx, pts %llx", offset, pts);
 380                         } else
 381                                 eDebug("MPEG4 AVC UAD but no valid PTS value.");
 382                 }
 383         }
 384         return 0;
 385 }
 386
 387 inline int eMPEGStreamParserTS::wantPacket(const unsigned char *hdr) const
 388 {
 389         if (hdr[0] != 0x47)
 390         {
 391                 eDebug("missing sync!");
 392                 return 0;
 393         }
 394         int ppid = ((hdr[1]&0x1F) << 8) | hdr[2];
 395
 396         if (ppid != m_pid)
 397                 return 0;
 398
 399         if (m_need_next_packet)  /* next packet (on this pid) was required? */
 400                 return 1;
 401
 402         if (hdr[1] & 0x40)       /* pusi set: yes. */
 403                 return 1;
 404
 405         return 0;
 406 }
 407
 408 void eMPEGStreamParserTS::parseData(off_t offset, const void *data, unsigned int len)
 409 {
 410         const unsigned char *packet = (const unsigned char*)data;
 411         const unsigned char *packet_start = packet;
 412
 413                         /* sorry for the redundant code here, but there are too many special cases... */
 414         while (len)
 415         {
 416                         /* emergency resync. usually, this should not happen, because the data should
 417                            be sync-aligned.
 418
 419                            to make this code work for non-strictly-sync-aligned data, (for example, bad
 420                            files) we fix a possible resync here by skipping data until the next 0x47.
 421
 422                            if this is a false 0x47, the packet will be dropped by wantPacket, and the
 423                            next time, sync will be re-established. */
 424                 int skipped = 0;
 425                 while (!m_pktptr && len)
 426                 {
 427                         if (packet[0] == 0x47)
 428                                 break;
 429                         len--;
 430                         packet++;
 431                         skipped++;
 432                 }
 433
 434                 if (skipped)
 435                         eDebug("SYNC LOST: skipped %d bytes.", skipped);
 436
 437                 if (!len)
 438                         break;
 439
 440                 if (m_pktptr)
 441                 {
 442                                 /* skip last packet */
 443                         if (m_pktptr < 0)
 444                         {
 445                                 unsigned int skiplen = -m_pktptr;
 446                                 if (skiplen > len)
 447                                         skiplen = len;
 448                                 packet += skiplen;
 449                                 len -= skiplen;
 450                                 m_pktptr += skiplen;
 451                                 continue;
 452                         } else if (m_pktptr < 4) /* header not complete, thus we don't know if we want this packet */
 453                         {
 454                                 unsigned int storelen = 4 - m_pktptr;
 455                                 if (storelen > len)
 456                                         storelen = len;
 457                                 memcpy(m_pkt + m_pktptr, packet,  storelen);
 458
 459                                 m_pktptr += storelen;
 460                                 len -= storelen;
 461                                 packet += storelen;
 462
 463                                 if (m_pktptr == 4)
 464                                         if (!wantPacket(m_pkt))
 465                                         {
 466                                                         /* skip packet */
 467                                                 packet += 184;
 468                                                 len -= 184;
 469                                                 m_pktptr = 0;
 470                                                 continue;
 471                                         }
 472                         }
 473                                 /* otherwise we complete up to the full packet */
 474                         unsigned int storelen = 188 - m_pktptr;
 475                         if (storelen > len)
 476                                 storelen = len;
 477                         memcpy(m_pkt + m_pktptr, packet,  storelen);
 478                         m_pktptr += storelen;
 479                         len -= storelen;
 480                         packet += storelen;
 481
 482                         if (m_pktptr == 188)
 483                         {
 484                                 m_need_next_packet = processPacket(m_pkt, offset + (packet - packet_start));
 485                                 m_pktptr = 0;
 486                         }
 487                 } else if (len >= 4)  /* if we have a full header... */
 488                 {
 489                         if (wantPacket(packet))  /* decide wheter we need it ... */
 490                         {
 491                                 if (len >= 188)          /* packet complete? */
 492                                 {
 493                                         m_need_next_packet = processPacket(packet, offset + (packet - packet_start)); /* process it now. */
 494                                 } else
 495                                 {
 496                                         memcpy(m_pkt, packet, len);  /* otherwise queue it up */
 497                                         m_pktptr = len;
 498                                 }
 499                         }
 500
 501                                 /* skip packet */
 502                         int sk = len;
 503                         if (sk >= 188)
 504                                 sk = 188;
 505                         else if (!m_pktptr) /* we dont want this packet, otherwise m_pktptr = sk (=len) > 4 */
 506                                 m_pktptr = sk - 188;
 507
 508                         len -= sk;
 509                         packet += sk;
 510                 } else             /* if we don't have a complete header */
 511                 {
 512                         memcpy(m_pkt, packet, len);   /* complete header next time */
 513                         m_pktptr = len;
 514                         packet += len;
 515                         len = 0;
 516                 }
 517         }
 518 }
 519
 520 void eMPEGStreamParserTS::setPid(int _pid)
 521 {
 522         m_pktptr = 0;
 523         m_pid = _pid;
 524 }