コード例 #1
0
            private void ValidateTable(BitSplitter bs)
            {
                int pointer = (int)bs.GetInteger(8);

                if (pointer != 0)
                {
                    throw new DemuxException("Non-zero pointers are not currently supported");
                }

                int table_id = (int)bs.GetInteger(8);

                if (table_id != 0x02)
                {
                    throw new DemuxException("Wrong table ID for PMT");
                }

                SectionSyntax = bs.GetFlag();
                if (!SectionSyntax)
                {
                    throw new DemuxException("Invalid PMT: incorrect section syntax");
                }
                bool zero = bs.GetFlag();

                if (zero)
                {
                    throw new DemuxException("Invalid PMT: zero bit wasn't zero");
                }
            }
コード例 #2
0
 private void ReadTransportHeader(BitSplitter bs)
 {
     bs.SkipToNextByte();                 // Sync byte
     Error            = bs.GetFlag();
     StartIndicator   = bs.GetFlag();
     HighPriority     = bs.GetFlag();
     PID              = (int)bs.GetInteger(13);
     ScrambleCode     = (int)bs.GetInteger(2);
     HasAdaptionField = bs.GetFlag();
     HasPayload       = bs.GetFlag();
     Counter          = (int)bs.GetInteger(4);
 }
コード例 #3
0
            private void CheckAdaptionField(BitSplitter bs)
            {
                if (HasAdaptionField)
                {
                    int adaption_end = (int)bs.GetInteger(8);
                    adaption_end += bs.ByteOffset;
                    Discont       = bs.GetFlag();
                    KeyFrame      = bs.GetFlag();
                    ES_Prio       = bs.GetFlag();
                    HasPCR        = bs.GetFlag();
                    HasOPCR       = bs.GetFlag();
                    HasSplice     = bs.GetFlag();
                    PrivateFlag   = bs.GetFlag();
                    AdapExtFlag   = bs.GetFlag();
                    if (bs.BitOffset != 0)
                    {
                        throw new Exception("bit align problem");
                    }

                    if (HasPCR)
                    {
                        PCR = (long)bs.GetInteger(33);
                        bs.SkipBits(15);                         // throw away useless sync stuff.
                    }
                    if (HasOPCR)
                    {
                        bs.SkipBits(48);                              // throw away useless "old" timecode
                    }
                    if (HasSplice)
                    {
                        bs.SkipBits(8);                                // throw away splice counter
                    }
                    if (PrivateFlag)
                    {
                        int priv_len = (int)bs.GetInteger(8);
                        bs.SkipBytes(priv_len);                         // skip private data
                    }
                    // ignore the rest of the adaption field (it's mostly to support stuff we ignore)
                    int skip_len = adaption_end - bs.ByteOffset;
                    bs.SkipBytes(skip_len);
                }
            }
コード例 #4
0
            private int SectionNumber, LastSection;             // should always be zero

            /// <summary>
            /// Digest a packet payload into structured table. Payload should be from the pointer field onward.
            /// Does not yet handle multi-packet tables
            /// </summary>
            public PAT(byte[] RawPayload)
            {
                Map = new Dictionary <int, int>();
                BitSplitter bs = new BitSplitter(RawPayload);

                ValidateTable(bs);

                bs.SkipBits(2);                 // reserved;
                SectionLength = (int)bs.GetInteger(12);
                TransportID   = (int)bs.GetInteger(16);
                bs.SkipBits(2);                 // reserved
                Version       = (int)bs.GetInteger(5);
                IsCurrent     = bs.GetFlag();
                SectionNumber = (int)bs.GetInteger(8);
                LastSection   = (int)bs.GetInteger(8);

                int bits_left = (SectionLength - 5) - 4;                 // remaining length in bytes, excluding CRC
                int items     = bits_left / 4;

                for (int i = 0; i < items; i++)
                {
                    int prog = (int)bs.GetInteger(16);
                    bs.SkipBits(3);
                    int pid = (int)bs.GetInteger(13);
                    if (!Map.ContainsKey(prog))
                    {
                        Map.Add(prog, pid);
                    }
                    else
                    {
                        throw new DemuxException("Invalid PAT: program number specified more than once (" + prog + ")");
                    }
                }

                // Ignoring CRC.
            }
コード例 #5
0
            /// <summary>
            /// Reads the long list of flags in the default PES header.
            /// </summary>
            private void ReadFlags(BitSplitter bs)
            {
                ScrambleControl = (int)bs.GetInteger(2);
                HighPriority    = bs.GetFlag();
                HasAlignment    = bs.GetFlag();
                IsCopyright     = bs.GetFlag();
                IsOriginal      = bs.GetFlag();
                HasPTS          = bs.GetFlag();
                HasDTS          = bs.GetFlag();

                if (HasDTS && !HasPTS)
                {
                    throw new DemuxException("Invalid PES: DTS without PTS is not allowed");
                }

                HasESCR         = bs.GetFlag();
                HasEsRate       = bs.GetFlag();
                UsesTrickMode   = bs.GetFlag();
                MoreCopyright   = bs.GetFlag();
                HasPesCRC       = bs.GetFlag();
                HasPesExtension = bs.GetFlag();
            }
コード例 #6
0
            /// <summary>
            /// Digest a packet payload into structured table. Payload should be from the pointer field onward.
            /// Does not yet handle multi-packet tables
            /// </summary>
            public PMT(byte[] RawPayload)
            {
                BitSplitter bs = new BitSplitter(RawPayload);

                Map        = new Dictionary <int, int>();
                ReverseMap = new Dictionary <StreamType, int>();

                ValidateTable(bs);

                bs.SkipBits(2);
                SectionLength = (int)bs.GetInteger(12);                 // total length after this, in bytes; includes 4 byte CRC.
                ProgramNumber = (int)bs.GetInteger(16);
                bs.SkipBits(2);

                Version       = (int)bs.GetInteger(5);
                IsCurrent     = bs.GetFlag();
                SectionNumber = (int)bs.GetInteger(8);
                LastSection   = (int)bs.GetInteger(8);
                bs.SkipBits(3);
                PCR_PID = (int)bs.GetInteger(13);                 // Either the PID of a channel timecode stream, or 0x1FFF for none.
                bs.SkipBits(4);

                ProgInfoLength = (int)bs.GetInteger(12);                 // number of bytes of descriptors.
                if (bs.BitOffset != 0)
                {
                    throw new DemuxException("Byte alignment error (internal)");
                }
                bs.SkipBytes(ProgInfoLength);                           // ignore descriptors.

                int info_bytes = (SectionLength - ProgInfoLength) - 13; // bytes of descriptor.

                while (info_bytes > 0)                                  // descriptions can be variable length
                {
                    int stream_type = (int)bs.GetInteger(8);
                    bs.SkipBits(3);
                    int pid = (int)bs.GetInteger(13);
                    bs.SkipBits(4);

                    if (!Map.ContainsKey(pid))
                    {
                        Map.Add(pid, stream_type);                                            // more complete map of pid types
                    }
                    else
                    {
                        throw new DemuxException("Invalid PMT: PID specified more than once");
                    }

                    StreamType st = DecodeStreamType(stream_type);
                    if (!ReverseMap.ContainsKey(st))
                    {
                        ReverseMap.Add(st, pid);                                                  // store first pid of each type
                    }
                    int es_info_length = (int)bs.GetInteger(12);
                    bs.SkipBytes(es_info_length);
                    info_bytes -= 5 + es_info_length;
                }
                if (bs.BitOffset != 0)
                {
                    throw new DemuxException("Invalid PMT: program info length didn't match data");
                }

                // ignoring CRC.
            }