C# NVorbis.DataPacket类代码示例

        internal int DecodeScalar(DataPacket packet)
        {
            int bitCnt;
            var bits = (int)packet.TryPeekBits(PrefixBitLength, out bitCnt);
            if (bitCnt == 0) return -1;

            // try to get the value from the prefix list...
            var node = PrefixList[bits];
            if (node != null)
            {
                packet.SkipBits(node.Length);
                return node.Value;
            }

            // nope, not possible... run the tree
            bits = (int)packet.TryPeekBits(MaxBits, out bitCnt);

            node = PrefixOverflowTree;
            do
            {
                if (node.Bits == (bits & node.Mask))
                {
                    packet.SkipBits(node.Length);
                    return node.Value;
                }
            } while ((node = node.Next) != null);
            return -1;
        }

        internal static VorbisMode Init(VorbisStreamDecoder vorbis, DataPacket packet)
        {
            var mode = new VorbisMode(vorbis);
            mode.BlockFlag = packet.ReadBit();
            mode.WindowType = (int)packet.ReadBits(16);
            mode.TransformType = (int)packet.ReadBits(16);
            var mapping = (int)packet.ReadBits(8);

            if (mode.WindowType != 0 || mode.TransformType != 0 || mapping >= vorbis.Maps.Length) throw new InvalidDataException();

            mode.Mapping = vorbis.Maps[mapping];
            mode.BlockSize = mode.BlockFlag ? vorbis.Block1Size : vorbis.Block0Size;

            // now pre-calc the window(s)...
            if (mode.BlockFlag)
            {
                // long block
                mode._windows = new float[4][];
                mode._windows[0] = new float[vorbis.Block1Size];
                mode._windows[1] = new float[vorbis.Block1Size];
                mode._windows[2] = new float[vorbis.Block1Size];
                mode._windows[3] = new float[vorbis.Block1Size];
            }
            else
            {
                // short block
                mode._windows = new float[1][];
                mode._windows[0] = new float[vorbis.Block0Size];
            }
            mode.CalcWindows();

            return mode;
        }

 internal static VorbisCodebook Init(VorbisStreamDecoder vorbis, DataPacket packet, int number)
 {
     var temp = new VorbisCodebook();
     temp.BookNum = number;
     temp.Init(packet);
     return temp;
 }

 internal void AddPacket(DataPacket packet)
 {
   if (packet.IsResync)
   {
     packet.IsContinuation = false;
     if (this._last != null)
       this._last.IsContinued = false;
   }
   if (packet.IsContinuation)
   {
     if (this._last == null)
       throw new InvalidDataException();
     if (!this._last.IsContinued)
       throw new InvalidDataException();
     this._last.MergeWith(packet);
     this._last.IsContinued = packet.IsContinued;
   }
   else
   {
     Packet packet1 = packet as Packet;
     if (packet1 == null)
       throw new ArgumentException("Wrong packet datatype", "packet");
     if (this._first == null)
     {
       this._first = packet1;
       this._last = packet1;
     }
     else
       this._last = (packet1.Prev = this._last).Next = packet1;
   }
   PacketReader packetReader = this;
   int num = packetReader._eosFound | packet.IsEndOfStream ? 1 : 0;
   packetReader._eosFound = num != 0;
 }

 internal static VorbisMode Init(VorbisStreamDecoder vorbis, DataPacket packet)
 {
   VorbisMode vorbisMode = new VorbisMode(vorbis);
   vorbisMode.BlockFlag = packet.ReadBit();
   vorbisMode.WindowType = (int) packet.ReadBits(16);
   vorbisMode.TransformType = (int) packet.ReadBits(16);
   int index = (int) packet.ReadBits(8);
   if (vorbisMode.WindowType != 0 || vorbisMode.TransformType != 0 || index >= vorbis.Maps.Length)
     throw new InvalidDataException();
   vorbisMode.Mapping = vorbis.Maps[index];
   vorbisMode.BlockSize = vorbisMode.BlockFlag ? vorbis.Block1Size : vorbis.Block0Size;
   if (vorbisMode.BlockFlag)
   {
     vorbisMode._windows = new float[4][];
     vorbisMode._windows[0] = new float[vorbis.Block1Size];
     vorbisMode._windows[1] = new float[vorbis.Block1Size];
     vorbisMode._windows[2] = new float[vorbis.Block1Size];
     vorbisMode._windows[3] = new float[vorbis.Block1Size];
   }
   else
   {
     vorbisMode._windows = new float[1][];
     vorbisMode._windows[0] = new float[vorbis.Block0Size];
   }
   vorbisMode.CalcWindows();
   return vorbisMode;
 }

 internal static VorbisCodebook Init(VorbisStreamDecoder vorbis, DataPacket packet, int number)
 {
   VorbisCodebook vorbisCodebook = new VorbisCodebook();
   vorbisCodebook.BookNum = number;
   vorbisCodebook.Init(packet);
   return vorbisCodebook;
 }

            protected override void Init(DataPacket packet)
            {
                var submapCount = 1;
                if (packet.ReadBit()) submapCount += (int)packet.ReadBits(4);

                // square polar mapping
                var couplingSteps = 0;
                if (packet.ReadBit())
                {
                    couplingSteps = (int)packet.ReadBits(8) + 1;
                }

                var couplingBits = Utils.ilog(_vorbis._channels - 1);
                CouplingSteps = new CouplingStep[couplingSteps];
                for (int j = 0; j < couplingSteps; j++)
                {
                    var magnitude = (int)packet.ReadBits(couplingBits);
                    var angle = (int)packet.ReadBits(couplingBits);
                    if (magnitude == angle || magnitude > _vorbis._channels - 1 || angle > _vorbis._channels - 1)
                        throw new Exception();
                    CouplingSteps[j] = new CouplingStep { Angle = angle, Magnitude = magnitude };
                }

                // reserved bits
                if (packet.ReadBits(2) != 0UL) throw new Exception();

                // channel multiplex
                var mux = new int[_vorbis._channels];
                if (submapCount > 1)
                {
                    for (int c = 0; c < ChannelSubmap.Length; c++)
                    {
                        mux[c] = (int)packet.ReadBits(4);
                        if (mux[c] >= submapCount) throw new Exception();
                    }
                }

                // submaps
                Submaps = new Submap[submapCount];
                for (int j = 0; j < submapCount; j++)
                {
                    packet.ReadBits(8); // unused placeholder
                    var floorNum = (int)packet.ReadBits(8);
                    if (floorNum >= _vorbis.Floors.Length) throw new Exception();
                    var residueNum = (int)packet.ReadBits(8);
                    if (residueNum >= _vorbis.Residues.Length) throw new Exception();

                    Submaps[j] = new Submap
                    {
                        Floor = _vorbis.Floors[floorNum],
                        Residue = _vorbis.Residues[floorNum]
                    };
                }

                ChannelSubmap = new Submap[_vorbis._channels];
                for (int c = 0; c < ChannelSubmap.Length; c++)
                {
                    ChannelSubmap[c] = Submaps[mux[c]];
                }
            }

 internal static VorbisMapping Init(VorbisStreamDecoder vorbis, DataPacket packet)
 {
   int num = (int) packet.ReadBits(16);
   VorbisMapping vorbisMapping = (VorbisMapping) null;
   if (num == 0)
     vorbisMapping = (VorbisMapping) new VorbisMapping.Mapping0(vorbis);
   if (vorbisMapping == null)
     throw new InvalidDataException();
   vorbisMapping.Init(packet);
   return vorbisMapping;
 }

 internal static VorbisTime Init(VorbisStreamDecoder vorbis, DataPacket packet)
 {
   int num = (int) packet.ReadBits(16);
   VorbisTime vorbisTime = (VorbisTime) null;
   if (num == 0)
     vorbisTime = (VorbisTime) new VorbisTime.Time0(vorbis);
   if (vorbisTime == null)
     throw new InvalidDataException();
   vorbisTime.Init(packet);
   return vorbisTime;
 }

 protected override void Init(DataPacket packet)
 {
   this._begin = (int) packet.ReadBits(24);
   this._end = (int) packet.ReadBits(24);
   this._partitionSize = (int) packet.ReadBits(24) + 1;
   this._classifications = (int) packet.ReadBits(6) + 1;
   this._classBookNum = (int) packet.ReadBits(8);
   this._classBook = this._vorbis.Books[this._classBookNum];
   this._cascade = new int[this._classifications];
   int length = 0;
   int val2 = 0;
   for (int index = 0; index < this._classifications; ++index)
   {
     int num1 = 0;
     int num2 = (int) packet.ReadBits(3);
     if (packet.ReadBit())
       num1 = (int) packet.ReadBits(5);
     this._cascade[index] = num1 << 3 | num2;
     length += VorbisResidue.Residue0.icount(this._cascade[index]);
     val2 = Math.Max(Utils.ilog(this._cascade[index]), val2);
   }
   this._maxPasses = val2;
   int[] numArray = new int[length];
   for (int index = 0; index < length; ++index)
     numArray[index] = (int) packet.ReadBits(8);
   int num3 = 0;
   this._books = new VorbisCodebook[this._classifications][];
   this._bookNums = new int[this._classifications][];
   for (int index1 = 0; index1 < this._classifications; ++index1)
   {
     this._books[index1] = new VorbisCodebook[8];
     this._bookNums[index1] = new int[8];
     int num1 = 1;
     int index2 = 0;
     while (num1 < 256)
     {
       if ((this._cascade[index1] & num1) == num1)
       {
         int index3 = numArray[num3++];
         this._books[index1][index2] = this._vorbis.Books[index3];
         this._bookNums[index1][index2] = index3;
         if (this._books[index1][index2].MapType == 0)
           throw new InvalidDataException();
       }
       num1 <<= 1;
       ++index2;
     }
   }
   this._classWordsPerCodeWord = this._classBook.Dimensions;
   this._nToRead = this._end - this._begin;
   this._partsToRead = this._nToRead / this._partitionSize;
   this._partWords = (this._partsToRead + this._classWordsPerCodeWord - 1) / this._classWordsPerCodeWord;
 }

        internal static VorbisTime Init(VorbisStreamDecoder vorbis, DataPacket packet)
        {
            var type = (int)packet.ReadBits(16);

            VorbisTime time = null;
            switch (type)
            {
                case 0: time = new Time0(vorbis); break;
            }
            if (time == null) throw new InvalidDataException();

            time.Init(packet);
            return time;
        }

        internal static VorbisFloor Init(VorbisStreamDecoder vorbis, DataPacket packet)
        {
            var type = (int)packet.ReadBits(16);

            VorbisFloor floor = null;
            switch (type)
            {
                case 0: floor = new Floor0(vorbis); break;
                case 1: floor = new Floor1(vorbis); break;
            }
            if (floor == null) throw new InvalidDataException();

            floor.Init(packet);
            return floor;
        }

 protected override void Init(DataPacket packet)
 {
   this._order = (int) packet.ReadBits(8);
   this._rate = (int) packet.ReadBits(16);
   this._bark_map_size = (int) packet.ReadBits(16);
   this._ampBits = (int) packet.ReadBits(6);
   this._ampOfs = (int) packet.ReadBits(8);
   this._books = new VorbisCodebook[(int) packet.ReadBits(4) + 1];
   for (int index = 0; index < this._books.Length; ++index)
     this._books[index] = this._vorbis.Books[(int) packet.ReadBits(8)];
   this._bookBits = Utils.ilog(this._books.Length);
   this._barkMaps = new Dictionary<int, float[]>();
   this._barkMaps[this._vorbis.Block0Size] = this.SynthesizeBarkCurve(this._vorbis.Block0Size);
   this._barkMaps[this._vorbis.Block1Size] = this.SynthesizeBarkCurve(this._vorbis.Block1Size);
 }

 protected override void DoMergeWith(DataPacket continuation)
 {
   Packet packet1 = continuation as Packet;
   if (packet1 == null)
     throw new ArgumentException("Incorrect packet type!");
   Packet packet2 = this;
   int num = packet2.Length + continuation.Length;
   packet2.Length = num;
   if (this._mergedPacket == null)
     this._mergedPacket = packet1;
   else
     this._mergedPacket.DoMergeWith(continuation);
   this.PageGranulePosition = continuation.PageGranulePosition;
   this.PageSequenceNumber = continuation.PageSequenceNumber;
 }

        internal void Init(DataPacket packet)
        {
            // first, check the sync pattern
            var chkVal = packet.ReadBits(24);
            if (chkVal != 0x564342UL) throw new  Exception();

            // get the counts
            Dimensions = (int)packet.ReadBits(16);
            Entries = (int)packet.ReadBits(24);
            
            // init the storage
            Lengths = new int[Entries];

            InitTree(packet);
            InitLookupTable(packet);
        }