Beispiel #1
0
        // Debug
        //    public void dumpHeap() {
        //        subAlloc.dumpHeap();
        //    }

        internal bool DecodeInit(Stream stream, int maxOrder, int maxMemory)
        {
            if (stream != null)
            {
                Coder = new RangeCoder(stream);
            }

            if (maxOrder == 1)
            {
                SubAlloc.StopSubAllocator();
                return(false);
            }
            SubAlloc.StartSubAllocator(maxMemory);
            _minContext = new PpmContext(Heap);

            //medContext = new PPMContext(Heap);
            _maxContext    = new PpmContext(Heap);
            FoundState     = new State(Heap);
            _dummySee2Cont = new See2Context();
            for (int i = 0; i < 25; i++)
            {
                for (int j = 0; j < 16; j++)
                {
                    _see2Cont[i][j] = new See2Context();
                }
            }
            StartModelRare(maxOrder);

            return(_minContext.Address != 0);
        }
Beispiel #2
0
 private void InitBlock()
 {
     for (int i = 0; i < 25; i++)
     {
         _see2Cont[i] = new See2Context[16];
     }
     for (int i2 = 0; i2 < 128; i2++)
     {
         _binSumm[i2] = new int[64];
     }
 }
Beispiel #3
0
        internal bool DecodeInit(IRarUnpack unpackRead, int escChar)
        {
            int  maxOrder = unpackRead.Char & 0xff;
            bool reset    = ((maxOrder & 0x20) != 0);

            int maxMb = 0;

            if (reset)
            {
                maxMb = unpackRead.Char;
            }
            else
            {
                if (SubAlloc.GetAllocatedMemory() == 0)
                {
                    return(false);
                }
            }
            if ((maxOrder & 0x40) != 0)
            {
                escChar = unpackRead.Char;
                unpackRead.PpmEscChar = escChar;
            }
            Coder = new RangeCoder(unpackRead);
            if (reset)
            {
                maxOrder = (maxOrder & 0x1f) + 1;
                if (maxOrder > 16)
                {
                    maxOrder = 16 + (maxOrder - 16) * 3;
                }
                if (maxOrder == 1)
                {
                    SubAlloc.StopSubAllocator();
                    return(false);
                }
                SubAlloc.StartSubAllocator((maxMb + 1) << 20);
                _minContext = new PpmContext(Heap);

                //medContext = new PPMContext(Heap);
                _maxContext    = new PpmContext(Heap);
                FoundState     = new State(Heap);
                _dummySee2Cont = new See2Context();
                for (int i = 0; i < 25; i++)
                {
                    for (int j = 0; j < 16; j++)
                    {
                        _see2Cont[i][j] = new See2Context();
                    }
                }
                StartModelRare(maxOrder);
            }
            return(_minContext.Address != 0);
        }
Beispiel #4
0
        internal bool DecodeSymbol2(ModelPpm model)
        {
            long        count;
            int         hiCnt, i = NumStats - model.NumMasked;
            See2Context psee2C = MakeEscFreq2(model, i);
            RangeCoder  coder  = model.Coder;

            // STATE* ps[256], ** pps=ps, * p=U.Stats-1;
            State p    = _tempState1.Initialize(model.Heap);
            State temp = _tempState2.Initialize(model.Heap);

            p.Address = _freqData.GetStats() - State.SIZE;
            int pps = 0;

            hiCnt = 0;

            do
            {
                do
                {
                    p.IncrementAddress(); // p++;
                }while (model.CharMask[p.Symbol] == model.EscCount);
                hiCnt     += p.Freq;
                _ps[pps++] = p.Address;
            }while (--i != 0);
            coder.SubRange.IncScale(hiCnt);
            count = coder.CurrentCount;
            if (count >= coder.SubRange.Scale)
            {
                return(false);
            }
            pps       = 0;
            p.Address = _ps[pps];
            if (count < hiCnt)
            {
                hiCnt = 0;
                while ((hiCnt += p.Freq) <= count)
                {
                    p.Address = _ps[++pps]; // p=*++pps;
                }
                coder.SubRange.HighCount = hiCnt;
                coder.SubRange.LowCount  = hiCnt - p.Freq;
                psee2C.Update();
                Update2(model, p.Address);
            }
            else
            {
                coder.SubRange.LowCount  = hiCnt;
                coder.SubRange.HighCount = coder.SubRange.Scale;
                i = NumStats - model.NumMasked; // ->NumMasked;
                pps--;
                do
                {
                    temp.Address = _ps[++pps]; // (*++pps)
                    model.CharMask[temp.Symbol] = model.EscCount;
                }while (--i != 0);
                psee2C.IncSumm((int)coder.SubRange.Scale);
                model.NumMasked = NumStats;
            }
            return(true);
        }