summaryrefslogtreecommitdiff
path: root/remux.h
blob: 23ce681efb68d6763c87c3ec74eb9c0aa1ec34a7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
/*
 * remux.h: Tools for detecting frames and handling PAT/PMT
 *
 * See the main source file 'vdr.c' for copyright information and
 * how to reach the author.
 *
 * $Id: remux.h 3.4 2014/03/26 11:42:17 kls Exp $
 */

#ifndef __REMUX_H
#define __REMUX_H

#include "channels.h"
#include "tools.h"

enum ePesHeader {
  phNeedMoreData = -1,
  phInvalid = 0,
  phMPEG1 = 1,
  phMPEG2 = 2
  };

ePesHeader AnalyzePesHeader(const uchar *Data, int Count, int &PesPayloadOffset, bool *ContinuationHeader = NULL);

class cRemux {
public:
  static void SetBrokenLink(uchar *Data, int Length);
  };

// Some TS handling tools.
// The following functions all take a pointer to one complete TS packet.

#define TS_SYNC_BYTE          0x47
#define TS_SIZE               188
#define TS_ERROR              0x80
#define TS_PAYLOAD_START      0x40
#define TS_TRANSPORT_PRIORITY 0x20
#define TS_PID_MASK_HI        0x1F
#define TS_SCRAMBLING_CONTROL 0xC0
#define TS_ADAPT_FIELD_EXISTS 0x20
#define TS_PAYLOAD_EXISTS     0x10
#define TS_CONT_CNT_MASK      0x0F
#define TS_ADAPT_DISCONT      0x80
#define TS_ADAPT_RANDOM_ACC   0x40 // would be perfect for detecting independent frames, but unfortunately not used by all broadcasters
#define TS_ADAPT_ELEM_PRIO    0x20
#define TS_ADAPT_PCR          0x10
#define TS_ADAPT_OPCR         0x08
#define TS_ADAPT_SPLICING     0x04
#define TS_ADAPT_TP_PRIVATE   0x02
#define TS_ADAPT_EXTENSION    0x01

#define PATPID 0x0000 // PAT PID (constant 0)
#define CATPID 0x0001 // CAT PID (constant 1)
#define MAXPID 0x2000 // for arrays that use a PID as the index

#define PTSTICKS  90000 // number of PTS ticks per second
#define PCRFACTOR 300 // conversion from 27MHz PCR extension to 90kHz PCR base
#define MAX33BIT  0x00000001FFFFFFFFLL // max. possible value with 33 bit
#define MAX27MHZ  ((MAX33BIT + 1) * PCRFACTOR - 1) // max. possible PCR value

inline bool TsHasPayload(const uchar *p)
{
  return p[3] & TS_PAYLOAD_EXISTS;
}

inline bool TsHasAdaptationField(const uchar *p)
{
  return p[3] & TS_ADAPT_FIELD_EXISTS;
}

inline bool TsPayloadStart(const uchar *p)
{
  return p[1] & TS_PAYLOAD_START;
}

inline bool TsError(const uchar *p)
{
  return p[1] & TS_ERROR;
}

inline int TsPid(const uchar *p)
{
  return (p[1] & TS_PID_MASK_HI) * 256 + p[2];
}

inline bool TsIsScrambled(const uchar *p)
{
  return p[3] & TS_SCRAMBLING_CONTROL;
}

inline uchar TsGetContinuityCounter(const uchar *p)
{
  return p[3] & TS_CONT_CNT_MASK;
}

inline void TsSetContinuityCounter(uchar *p, uchar Counter)
{
  p[3] = (p[3] & ~TS_CONT_CNT_MASK) | (Counter & TS_CONT_CNT_MASK);
}

inline int TsPayloadOffset(const uchar *p)
{
  int o = TsHasAdaptationField(p) ? p[4] + 5 : 4;
  return o <= TS_SIZE ? o : TS_SIZE;
}

inline int TsGetPayload(const uchar **p)
{
  if (TsHasPayload(*p)) {
     int o = TsPayloadOffset(*p);
     *p += o;
     return TS_SIZE - o;
     }
  return 0;
}

inline int TsContinuityCounter(const uchar *p)
{
  return p[3] & TS_CONT_CNT_MASK;
}

inline int64_t TsGetPcr(const uchar *p)
{
  if (TsHasAdaptationField(p)) {
     if (p[4] >= 7 && (p[5] & TS_ADAPT_PCR)) {
        return ((((int64_t)p[ 6]) << 25) |
                (((int64_t)p[ 7]) << 17) |
                (((int64_t)p[ 8]) <<  9) |
                (((int64_t)p[ 9]) <<  1) |
                (((int64_t)p[10]) >>  7)) * PCRFACTOR +
               (((((int)p[10]) & 0x01) << 8) |
                ( ((int)p[11])));
        }
     }
  return -1;
}

void TsHidePayload(uchar *p);
void TsSetPcr(uchar *p, int64_t Pcr);

// The following functions all take a pointer to a sequence of complete TS packets.

int64_t TsGetPts(const uchar *p, int l);
int64_t TsGetDts(const uchar *p, int l);
void TsSetPts(uchar *p, int l, int64_t Pts);
void TsSetDts(uchar *p, int l, int64_t Dts);

// Some PES handling tools:
// The following functions that take a pointer to PES data all assume that
// there is enough data so that PesLongEnough() returns true.

inline bool PesLongEnough(int Length)
{
  return Length >= 6;
}

inline bool PesHasLength(const uchar *p)
{
  return p[4] | p[5];
}

inline int PesLength(const uchar *p)
{
  return 6 + p[4] * 256 + p[5];
}

inline int PesPayloadOffset(const uchar *p)
{
  return 9 + p[8];
}

inline bool PesHasPts(const uchar *p)
{
  return (p[7] & 0x80) && p[8] >= 5;
}

inline bool PesHasDts(const uchar *p)
{
  return (p[7] & 0x40) && p[8] >= 10;
}

inline int64_t PesGetPts(const uchar *p)
{
  return ((((int64_t)p[ 9]) & 0x0E) << 29) |
         (( (int64_t)p[10])         << 22) |
         ((((int64_t)p[11]) & 0xFE) << 14) |
         (( (int64_t)p[12])         <<  7) |
         ((((int64_t)p[13]) & 0xFE) >>  1);
}

inline int64_t PesGetDts(const uchar *p)
{
  return ((((int64_t)p[14]) & 0x0E) << 29) |
         (( (int64_t)p[15])         << 22) |
         ((((int64_t)p[16]) & 0xFE) << 14) |
         (( (int64_t)p[17])         <<  7) |
         ((((int64_t)p[18]) & 0xFE) >>  1);
}

void PesSetPts(uchar *p, int64_t Pts);
void PesSetDts(uchar *p, int64_t Dts);

// PTS handling:

inline int64_t PtsAdd(int64_t Pts1, int64_t Pts2) { return (Pts1 + Pts2) & MAX33BIT; }
       ///< Adds the given PTS values, taking into account the 33bit wrap around.
int64_t PtsDiff(int64_t Pts1, int64_t Pts2);
       ///< Returns the difference between two PTS values. The result of Pts2 - Pts1
       ///< is the actual number of 90kHz time ticks that pass from Pts1 to Pts2,
       ///< properly taking into account the 33bit wrap around. If Pts2 is "before"
       ///< Pts1, the result is negative.

// A transprent TS payload handler:

class cTsPayload {
private:
  uchar *data;
  int length;
  int pid;
  int index; // points to the next byte to process
  int numPacketsPid; // the number of TS packets with the given PID (for statistical purposes)
  int numPacketsOther; // the number of TS packets with other PIDs (for statistical purposes)
  uchar SetEof(void);
protected:
  void Reset(void);
public:
  cTsPayload(void);
  cTsPayload(uchar *Data, int Length, int Pid = -1);
       ///< Creates a new TS payload handler and calls Setup() with the given Data.
  void Setup(uchar *Data, int Length, int Pid = -1);
       ///< Sets up this TS payload handler with the given Data, which points to a
       ///< sequence of Length bytes of complete TS packets. Any incomplete TS
       ///< packet at the end will be ignored.
       ///< If Pid is given, only TS packets with data for that PID will be processed.
       ///< Otherwise the PID of the first TS packet defines which payload will be
       ///< delivered.
       ///< Any intermediate TS packets with different PIDs will be skipped.
  bool AtTsStart(void) { return index < length && (index % TS_SIZE) == 0; }
       ///< Returns true if this payload handler is currently pointing to first byte
       ///< of a TS packet.
  bool AtPayloadStart(void) { return AtTsStart() && TsPayloadStart(data + index); }
       ///< Returns true if this payload handler is currently pointing to the first byte
       ///< of a TS packet that starts a new payload.
  int Available(void) { return length - index; }
       ///< Returns the number of raw bytes (including any TS headers) still available
       ///< in the TS payload handler.
  int Used(void) { return (index + TS_SIZE - 1) / TS_SIZE * TS_SIZE; }
       ///< Returns the number of raw bytes that have already been used (e.g. by calling
       ///< GetByte()). Any TS packet of which at least a single byte has been delivered
       ///< is counted with its full size.
  bool Eof(void) const { return index >= length; }
       ///< Returns true if all available bytes of the TS payload have been processed.
  void Statistics(void) const;
       ///< May be called after a new frame has been detected, and will log a warning
       ///< if the number of TS packets required to determine the frame type exceeded
       ///< some safety limits.
  uchar GetByte(void);
       ///< Gets the next byte of the TS payload, skipping any intermediate TS header data.
  bool SkipBytes(int Bytes);
       ///< Skips the given number of bytes in the payload and returns true if there
       ///< is still data left to read.
  bool SkipPesHeader(void);
       ///< Skips all bytes belonging to the PES header of the payload.
  int GetLastIndex(void);
       ///< Returns the index into the TS data of the payload byte that has most recently
       ///< been read. If no byte has been read yet, -1 will be returned.
  void SetByte(uchar Byte, int Index);
       ///< Sets the TS data byte at the given Index to the value Byte.
       ///< Index should be one that has been retrieved by a previous call to GetIndex(),
       ///< otherwise the behaviour is undefined. The current read index will not be
       ///< altered by a call to this function.
  bool Find(uint32_t Code);
       ///< Searches for the four byte sequence given in Code and returns true if it
       ///< was found within the payload data. The next call to GetByte() will return the
       ///< value immediately following the Code. If the code was not found, the read
       ///< index will remain the same as before this call, so that several calls to
       ///< Find() can be performed starting at the same index..
       ///< The special code 0xFFFFFFFF can not be searched, because this value is used
       ///< to initialize the scanner.
  };

// PAT/PMT Generator:

#define MAX_SECTION_SIZE 4096 // maximum size of an SI section
#define MAX_PMT_TS  (MAX_SECTION_SIZE / TS_SIZE + 1)

class cPatPmtGenerator {
private:
  uchar pat[TS_SIZE]; // the PAT always fits into a single TS packet
  uchar pmt[MAX_PMT_TS][TS_SIZE]; // the PMT may well extend over several TS packets
  int numPmtPackets;
  int patCounter;
  int pmtCounter;
  int patVersion;
  int pmtVersion;
  int pmtPid;
  uchar *esInfoLength;
  void IncCounter(int &Counter, uchar *TsPacket);
  void IncVersion(int &Version);
  void IncEsInfoLength(int Length);
protected:
  int MakeStream(uchar *Target, uchar Type, int Pid);
  int MakeAC3Descriptor(uchar *Target, uchar Type);
  int MakeSubtitlingDescriptor(uchar *Target, const char *Language, uchar SubtitlingType, uint16_t CompositionPageId, uint16_t AncillaryPageId);
  int MakeLanguageDescriptor(uchar *Target, const char *Language);
  int MakeCRC(uchar *Target, const uchar *Data, int Length);
  void GeneratePmtPid(const cChannel *Channel);
       ///< Generates a PMT pid that doesn't collide with any of the actual
       ///< pids of the Channel.
  void GeneratePat(void);
       ///< Generates a PAT section for later use with GetPat().
  void GeneratePmt(const cChannel *Channel);
       ///< Generates a PMT section for the given Channel, for later use
       ///< with GetPmt().
public:
  cPatPmtGenerator(const cChannel *Channel = NULL);
  void SetVersions(int PatVersion, int PmtVersion);
       ///< Sets the version numbers for the generated PAT and PMT, in case
       ///< this generator is used to, e.g.,  continue a previously interrupted
       ///< recording (in which case the numbers given should be derived from
       ///< the PAT/PMT versions last used in the existing recording, incremented
       ///< by 1. If the given numbers exceed the allowed range of 0..31, the
       ///< higher bits will automatically be cleared.
       ///< SetVersions() needs to be called before SetChannel() in order to
       ///< have an effect from the very start.
  void SetChannel(const cChannel *Channel);
       ///< Sets the Channel for which the PAT/PMT shall be generated.
  uchar *GetPat(void);
       ///< Returns a pointer to the PAT section, which consists of exactly
       ///< one TS packet.
  uchar *GetPmt(int &Index);
       ///< Returns a pointer to the Index'th TS packet of the PMT section.
       ///< Index must be initialized to 0 and will be incremented by each
       ///< call to GetPmt(). Returns NULL is all packets of the PMT section
       ///< have been fetched..
  };

// PAT/PMT Parser:

#define MAX_PMT_PIDS 32

class cPatPmtParser {
private:
  uchar pmt[MAX_SECTION_SIZE];
  int pmtSize;
  int patVersion;
  int pmtVersion;
  int pmtPids[MAX_PMT_PIDS + 1]; // list is zero-terminated
  int vpid;
  int ppid;
  int vtype;
  int apids[MAXAPIDS + 1]; // list is zero-terminated
  int atypes[MAXAPIDS + 1]; // list is zero-terminated
  char alangs[MAXAPIDS][MAXLANGCODE2];
  int dpids[MAXDPIDS + 1]; // list is zero-terminated
  int dtypes[MAXDPIDS + 1]; // list is zero-terminated
  char dlangs[MAXDPIDS][MAXLANGCODE2];
  int spids[MAXSPIDS + 1]; // list is zero-terminated
  char slangs[MAXSPIDS][MAXLANGCODE2];
  uchar subtitlingTypes[MAXSPIDS];
  uint16_t compositionPageIds[MAXSPIDS];
  uint16_t ancillaryPageIds[MAXSPIDS];
  bool updatePrimaryDevice;
protected:
  int SectionLength(const uchar *Data, int Length) { return (Length >= 3) ? ((int(Data[1]) & 0x0F) << 8)| Data[2] : 0; }
public:
  cPatPmtParser(bool UpdatePrimaryDevice = false);
  void Reset(void);
       ///< Resets the parser. This function must be called whenever a new
       ///< stream is parsed.
  void ParsePat(const uchar *Data, int Length);
       ///< Parses the PAT data from the single TS packet in Data.
       ///< Length is always TS_SIZE.
  void ParsePmt(const uchar *Data, int Length);
       ///< Parses the PMT data from the single TS packet in Data.
       ///< Length is always TS_SIZE.
       ///< The PMT may consist of several TS packets, which
       ///< are delivered to the parser through several subsequent calls to
       ///< ParsePmt(). The whole PMT data will be processed once the last packet
       ///< has been received.
  bool ParsePatPmt(const uchar *Data, int Length);
       ///< Parses the given Data (which may consist of several TS packets, typically
       ///< an entire frame) and extracts the PAT and PMT.
       ///< Returns true if a valid PAT/PMT has been detected.
  bool GetVersions(int &PatVersion, int &PmtVersion) const;
       ///< Returns true if a valid PAT/PMT has been parsed and stores
       ///< the current version numbers in the given variables.
  bool IsPmtPid(int Pid) const { for (int i = 0; pmtPids[i]; i++) if (pmtPids[i] == Pid) return true; return false; }
       ///< Returns true if Pid the one of the PMT pids as defined by the current PAT.
       ///< If no PAT has been received yet, false will be returned.
  int Vpid(void) const { return vpid; }
       ///< Returns the video pid as defined by the current PMT, or 0 if no video
       ///< pid has been detected, yet.
  int Ppid(void) const { return ppid; }
       ///< Returns the PCR pid as defined by the current PMT, or 0 if no PCR
       ///< pid has been detected, yet.
  int Vtype(void) const { return vtype; }
       ///< Returns the video stream type as defined by the current PMT, or 0 if no video
       ///< stream type has been detected, yet.
  const int *Apids(void) const { return apids; }
  const int *Dpids(void) const { return dpids; }
  const int *Spids(void) const { return spids; }
  int Apid(int i) const { return (0 <= i && i < MAXAPIDS) ? apids[i] : 0; }
  int Dpid(int i) const { return (0 <= i && i < MAXDPIDS) ? dpids[i] : 0; }
  int Spid(int i) const { return (0 <= i && i < MAXSPIDS) ? spids[i] : 0; }
  int Atype(int i) const { return (0 <= i && i < MAXAPIDS) ? atypes[i] : 0; }
  int Dtype(int i) const { return (0 <= i && i < MAXDPIDS) ? dtypes[i] : 0; }
  const char *Alang(int i) const { return (0 <= i && i < MAXAPIDS) ? alangs[i] : ""; }
  const char *Dlang(int i) const { return (0 <= i && i < MAXDPIDS) ? dlangs[i] : ""; }
  const char *Slang(int i) const { return (0 <= i && i < MAXSPIDS) ? slangs[i] : ""; }
  uchar SubtitlingType(int i) const { return (0 <= i && i < MAXSPIDS) ? subtitlingTypes[i] : uchar(0); }
  uint16_t CompositionPageId(int i) const { return (0 <= i && i < MAXSPIDS) ? compositionPageIds[i] : uint16_t(0); }
  uint16_t AncillaryPageId(int i) const { return (0 <= i && i < MAXSPIDS) ? ancillaryPageIds[i] : uint16_t(0); }
  };

// TS to PES converter:
// Puts together the payload of several TS packets that form one PES
// packet.

class cTsToPes {
private:
  uchar *data;
  int size;
  int length;
  int offset;
  uchar *lastData;
  int lastLength;
  bool repeatLast;
public:
  cTsToPes(void);
  ~cTsToPes();
  void PutTs(const uchar *Data, int Length);
       ///< Puts the payload data of the single TS packet at Data into the converter.
       ///< Length is always TS_SIZE.
       ///< If the given TS packet starts a new PES payload packet, the converter
       ///< will be automatically reset. Any packets before the first one that starts
       ///< a new PES payload packet will be ignored.
       ///< Once a TS packet has been put into a cTsToPes converter, all subsequent
       ///< packets until the next call to Reset() must belong to the same PID as
       ///< the first packet. There is no check whether this actually is the case, so
       ///< the caller is responsible for making sure this condition is met.
  const uchar *GetPes(int &Length);
       ///< Gets a pointer to the complete PES packet, or NULL if the packet
       ///< is not complete yet. If the packet is complete, Length will contain
       ///< the total packet length. The returned pointer is only valid until
       ///< the next call to PutTs() or Reset(), or until this object is destroyed.
       ///< Once GetPes() has returned a non-NULL value, it must be called
       ///< repeatedly, and the data processed, until it returns NULL. This
       ///< is because video packets may be larger than the data a single
       ///< PES packet with an actual length field can hold, and are therefore
       ///< split into several PES packets with smaller sizes.
       ///< Note that for video data GetPes() may only be called if the next
       ///< TS packet that will be given to PutTs() has the "payload start" flag
       ///< set, because this is the only way to determine the end of a video PES
       ///< packet.
  void SetRepeatLast(void);
       ///< Makes the next call to GetPes() return exactly the same data as the
       ///< last one (provided there was no call to Reset() in the meantime).
  void Reset(void);
       ///< Resets the converter. This needs to be called after a PES packet has
       ///< been fetched by a call to GetPes(), and before the next call to
       ///< PutTs().
  };

// Some helper functions for debugging:

void BlockDump(const char *Name, const u_char *Data, int Length);
void TsDump(const char *Name, const u_char *Data, int Length);
void PesDump(const char *Name, const u_char *Data, int Length);

// Frame detector:

#define MIN_TS_PACKETS_FOR_FRAME_DETECTOR 100

class cFrameParser;

class cFrameDetector {
private:
  enum { MaxPtsValues = 150 };
  int pid;
  int type;
  bool synced;
  bool newFrame;
  bool independentFrame;
  uint32_t ptsValues[MaxPtsValues]; // 32 bit is enough - we only need the delta
  int numPtsValues;
  int numIFrames;
  bool isVideo;
  double framesPerSecond;
  int framesInPayloadUnit;
  int framesPerPayloadUnit; // Some broadcasters send one frame per payload unit (== 1),
                            // while others put an entire GOP into one payload unit (> 1).
  bool scanning;
  cFrameParser *parser;
public:
  cFrameDetector(int Pid = 0, int Type = 0);
      ///< Sets up a frame detector for the given Pid and stream Type.
      ///< If no Pid and Type is given, they need to be set by a separate
      ///< call to SetPid().
  void SetPid(int Pid, int Type);
      ///< Sets the Pid and stream Type to detect frames for.
  int Analyze(const uchar *Data, int Length);
      ///< Analyzes the TS packets pointed to by Data. Length is the number of
      ///< bytes Data points to, and must be a multiple of TS_SIZE.
      ///< Returns the number of bytes that have been analyzed.
      ///< If the return value is 0, the data was not sufficient for analyzing and
      ///< Analyze() needs to be called again with more actual data.
  bool Synced(void) { return synced; }
      ///< Returns true if the frame detector has synced on the data stream.
  bool NewFrame(void) { return newFrame; }
      ///< Returns true if the data given to the last call to Analyze() started a
      ///< new frame.
  bool IndependentFrame(void) { return independentFrame; }
      ///< Returns true if a new frame was detected and this is an independent frame
      ///< (i.e. one that can be displayed by itself, without using data from any
      ///< other frames).
  double FramesPerSecond(void) { return framesPerSecond; }
      ///< Returns the number of frames per second, or 0 if this information is not
      ///< available.
  };

#endif // __REMUX_H