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MPEG2TransportStreamMultiplexor.hh
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16 // "liveMedia"
17 // Copyright (c) 1996-2021 Live Networks, Inc. All rights reserved.
18 // A class for generating MPEG-2 Transport Stream from one or more input
19 // Elementary Stream data sources
20 // C++ header
21 
22 #ifndef _MPEG2_TRANSPORT_STREAM_MULTIPLEXOR_HH
23 #define _MPEG2_TRANSPORT_STREAM_MULTIPLEXOR_HH
24 
25 #ifndef _FRAMED_SOURCE_HH
26 #include "FramedSource.hh"
27 #endif
28 #ifndef _MPEG_1OR2_DEMUX_HH
29 #include "MPEG1or2Demux.hh" // for SCR
30 #endif
31 
32 #define PID_TABLE_SIZE 0x2000 // 2^13
33 
35 public:
36  typedef void (onEndOfSegmentFunc)(void* clientData, double segmentDuration);
37  void setTimedSegmentation(unsigned segmentationDuration,
39  void* onEndOfSegmentClientData = NULL);
40  // Specifies that PAT and PMT packets should be output every "segmentationDuration" seconds.
41  // (If "segmentationDuration" is 0 (the default value), then PAT and PMT packets are output
42  // at a preset frequency.)
43  // The optional function "onEndOfSegmentFunc" is called after each segment is output.
45  // Valid only if "setTimedSegmentation()" was previously called with "segmentationDuration" > 0
46 
48  // Can be used by a downstream reader to test whether the next call to "doGetNextFrame()"
49  // will deliver data immediately).
50 
51 protected:
54 
55  virtual void awaitNewBuffer(unsigned char* oldBuffer) = 0;
56  // implemented by subclasses
57 
58  void handleNewBuffer(unsigned char* buffer, unsigned bufferSize,
59  int mpegVersion, MPEG1or2Demux::SCR scr, int16_t PID = -1);
60  // called by "awaitNewBuffer()"
61  // Note: For MPEG-4 video, set "mpegVersion" to 4; for H.264 video, set "mpegVersion" to 5;
62  // for H.265 video, set "mpegVersion" to 6.
63  // For Opus audio, set "mpegVersion" to 3.
64  // The buffer is assumed to be a PES packet, with a proper PES header.
65  // If "PID" is not -1, then it (currently, only the low 8 bits) is used as the stream's PID,
66  // otherwise the "stream_id" in the PES header is reused to be the stream's PID.
67 
68 private:
69  // Redefined virtual functions:
71  virtual void doGetNextFrame();
72 
73 private:
74  void deliverDataToClient(u_int16_t pid, unsigned char* buffer, unsigned bufferSize,
75  unsigned& startPositionInBuffer);
76 
78  void deliverPMTPacket(Boolean hasChanged);
79 
80  void setProgramStreamMap(unsigned frameSize);
81 
82 protected:
84 
85 private:
89  // These two fields are used if we see "program_stream_map"s in the input.
90  struct {
91  unsigned counter;
92  u_int8_t streamType; // for use in Program Maps
94  u_int16_t fPCR_PID, fCurrentPID; // only the low 13 bits are used
96  unsigned char* fInputBuffer;
100  // if nonzero, this is the number of seconds between successive 'segments'. Each 'segment'
101  // begins with a PAT, followed by a PMT.
102  // if zero (the default value), then the frequency of PATs and PMTs depends on the constants
103  // PAT_PERIOD_IF_UNTIMED and PMT_PERIOD_IF_UNTIMED, defined in the .cpp file.
106  // used only if fSegmentationDuration > 0:
107  // 1 if a segment has just ended and the next packet is to be a PAT
108  // 2 if a segment has just ended and the following PAT has been sent; a PMT is next
109  // 0 otherwise
110  double fCurrentSegmentDuration, fPreviousPTS; // used only if fSegmentationDuration > 0
111  onEndOfSegmentFunc* fOnEndOfSegmentFunc; // used only if fSegmentationDuration > 0
113 };
114 
115 
116 // The CRC calculation function that Transport Streams use. We make this function public
117 // here in case it's useful elsewhere:
118 u_int32_t calculateCRC(u_int8_t const* data, unsigned dataLength, u_int32_t initialValue = 0xFFFFFFFF);
119 
120 #endif
unsigned char Boolean
Definition: Boolean.hh:25
#define PID_TABLE_SIZE
u_int32_t calculateCRC(u_int8_t const *data, unsigned dataLength, u_int32_t initialValue=0xFFFFFFFF)
#define NULL
virtual Boolean isMPEG2TransportStreamMultiplexor() const
MPEG2TransportStreamMultiplexor(UsageEnvironment &env)
struct MPEG2TransportStreamMultiplexor::@2 fPIDState[PID_TABLE_SIZE]
void setTimedSegmentation(unsigned segmentationDuration, onEndOfSegmentFunc *onEndOfSegmentFunc=NULL, void *onEndOfSegmentClientData=NULL)
void deliverDataToClient(u_int16_t pid, unsigned char *buffer, unsigned bufferSize, unsigned &startPositionInBuffer)
void handleNewBuffer(unsigned char *buffer, unsigned bufferSize, int mpegVersion, MPEG1or2Demux::SCR scr, int16_t PID=-1)
virtual void awaitNewBuffer(unsigned char *oldBuffer)=0
void deliverPMTPacket(Boolean hasChanged)
void() onEndOfSegmentFunc(void *clientData, double segmentDuration)
void setProgramStreamMap(unsigned frameSize)