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* 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 2.32 2011/09/04 12:48:26 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 {
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_PID_MASK_HI 0x1F
#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 PATPID 0x0000 // PAT PID (constant 0)
#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)
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 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
class cPatPmtGenerator {
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);
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().
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:
class cPatPmtParser {
uchar pmt[MAX_SECTION_SIZE];
int pmtSize;
int patVersion;
int pmtVersion;
int pmtPid;
int vpid;
int ppid;
int vtype;
int apids[MAXAPIDS + 1]; // list is zero-terminated
int atypes[MAXAPIDS + 1]; // list is zero-terminated
int dpids[MAXDPIDS + 1]; // list is zero-terminated
int dtypes[MAXDPIDS + 1]; // list is zero-terminated
int spids[MAXSPIDS + 1]; // list is zero-terminated
uchar subtitlingTypes[MAXSPIDS];
uint16_t compositionPageIds[MAXSPIDS];
uint16_t ancillaryPageIds[MAXSPIDS];
bool updatePrimaryDevice;
int SectionLength(const uchar *Data, int Length) { return (Length >= 3) ? ((int(Data[1]) & 0x0F) << 8)| Data[2] : 0; }
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 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.
int PmtPid(void) const { 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) 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 {
uchar *data;
int size;
int length;
int offset;
uchar *lastData;
int lastLength;
bool repeatLast;
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:
class cFrameDetector {
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 numFrames;
int numIFrames;
bool isVideo;
double framesPerSecond;
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;
int SkipPackets(const uchar *&Data, int &Length, int &Processed, int &FrameTypeOffset);
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.
void Reset(void);
///< Resets any counters and flags used while syncing and prepares
///< the frame detector for actual work.
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