summaryrefslogtreecommitdiff
path: root/remux.h
blob: 3ee9c9e9b44d5ff36e991b98fa4437e918c1e9d8 (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
/*
 * 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 2.11 2009/05/10 13:43:52 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 MAXPID 0x2000 // for arrays that use a PID as the index

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 int TsPayloadOffset(const uchar *p)
{
  return (p[3] & TS_ADAPT_FIELD_EXISTS) ? p[4] + 5 : 4;
}

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

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

inline int TsGetAdaptationField(const uchar *p)
{
  return TsHasAdaptationField(p) ? p[5] : 0x00;
}

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

int64_t TsGetPts(const uchar *p, int l);
void TsSetTeiOnBrokenPackets(uchar *p, int l);

// 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 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);
}

// 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);
  int MakeSubtitlingDescriptor(uchar *Target, const char *Language);
  int MakeLanguageDescriptor(uchar *Target, const char *Language);
  int MakeCRC(uchar *Target, const uchar *Data, int Length);
  void GeneratePmtPid(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(cChannel *Channel);
       ///< Generates a PMT section for the given Channel, for later use
       ///< with GetPmt().
public:
  cPatPmtGenerator(cChannel *Channel = NULL);
  void SetChannel(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:

class cPatPmtParser {
private:
  uchar pmt[MAX_SECTION_SIZE];
  int pmtSize;
  int patVersion;
  int pmtVersion;
  int pmtPid;
  int vpid;
  int vtype;
protected:
  int SectionLength(const uchar *Data, int Length) { return (Length >= 3) ? ((int(Data[1]) & 0x0F) << 8)| Data[2] : 0; }
public:
  cPatPmtParser(void);
  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.
  int PmtPid(void) { return pmtPid; }
       ///< Returns the PMT pid as defined by the current PAT.
       ///< If no PAT has been received yet, -1 will be returned.
  int Vpid(void) { return vpid; }
       ///< Returns the video pid as defined by the current PMT.
  int Vtype(void) { return vtype; }
  };

// 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;
  bool synced;
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 188.
       ///< 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.
  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 packates with smaller sizes.
  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:

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;
  int frameDuration;
  int framesInPayloadUnit;
  int framesPerPayloadUnit; // Some broadcasters send one frame per payload unit (== 1),
                            // some put an entire GOP into one payload unit (> 1), and
                            // some spread a single frame over several payload units (< 0).
  int payloadUnitOfFrame;
  bool scanning;
  uint32_t scanner;
public:
  cFrameDetector(int Pid, int Type);
  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 188.
      ///< 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 frameDuration ? 90000.0 / frameDuration : 0; }
      ///< Returns the number of frames per second, or 0 if this information is not
      ///< available.
  };

#endif // __REMUX_H