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