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);
}
internal bool decodeSymbol2(ModelPPM model)
{
int diff = this.NumStats - model.NumMasked;
SEE2Context context = this.makeEscFreq2(model, diff);
RangeCoder coder = model.Coder;
SharpCompress.Compressor.PPMd.H.State state = this.tempState1.Initialize(model.Heap);
SharpCompress.Compressor.PPMd.H.State state2 = this.tempState2.Initialize(model.Heap);
state.Address = this.freqData.GetStats() - 6;
int index = 0;
int dScale = 0;
do
{
do
{
state.IncrementAddress();
}while (model.CharMask[state.Symbol] == model.EscCount);
dScale += state.Freq;
this.ps[index++] = state.Address;
}while (--diff != 0);
coder.SubRange.incScale(dScale);
long currentCount = coder.CurrentCount;
if (currentCount >= coder.SubRange.Scale)
{
return(false);
}
index = 0;
state.Address = this.ps[index];
if (currentCount < dScale)
{
dScale = 0;
while ((dScale += state.Freq) <= currentCount)
{
state.Address = this.ps[++index];
}
coder.SubRange.HighCount = dScale;
coder.SubRange.LowCount = dScale - state.Freq;
context.update();
this.update2(model, state.Address);
}
else
{
coder.SubRange.LowCount = dScale;
coder.SubRange.HighCount = coder.SubRange.Scale;
diff = this.NumStats - model.NumMasked;
index--;
do
{
state2.Address = this.ps[++index];
model.CharMask[state2.Symbol] = model.EscCount;
}while (--diff != 0);
context.incSumm((int)coder.SubRange.Scale);
model.NumMasked = this.NumStats;
}
return(true);
}
public int decodeChar(SharpCompress.Compressor.LZMA.RangeCoder.Decoder decoder)
{
SharpCompress.Compressor.PPMd.H.State state;
int num;
int threshold;
int num3;
byte symbol;
if (this.minContext.NumStats != 1)
{
state = this.tempState1.Initialize(this.Heap);
state.Address = this.minContext.FreqData.GetStats();
if ((threshold = (int)decoder.GetThreshold((uint)this.minContext.FreqData.SummFreq)) < (num3 = state.Freq))
{
decoder.Decode(0, (uint)state.Freq);
symbol = (byte)state.Symbol;
this.minContext.update1_0(this, state.Address);
this.nextContext();
return(symbol);
}
this.prevSuccess = 0;
num = this.minContext.NumStats - 1;
do
{
state.IncrementAddress();
if ((num3 += state.Freq) > threshold)
{
decoder.Decode((uint)(num3 - state.Freq), (uint)state.Freq);
symbol = (byte)state.Symbol;
this.minContext.update1(this, state.Address);
this.nextContext();
return(symbol);
}
}while (--num > 0);
if (threshold >= this.minContext.FreqData.SummFreq)
{
return(-2);
}
this.hiBitsFlag = this.HB2Flag[this.foundState.Symbol];
decoder.Decode((uint)num3, (uint)(this.minContext.FreqData.SummFreq - num3));
for (num = 0; num < 0x100; num++)
{
this.charMask[num] = -1;
}
this.charMask[state.Symbol] = 0;
num = this.minContext.NumStats - 1;
do
{
state.DecrementAddress();
this.charMask[state.Symbol] = 0;
}while (--num > 0);
}
else
{
SharpCompress.Compressor.PPMd.H.State rs = this.tempState1.Initialize(this.Heap);
rs.Address = this.minContext.getOneState().Address;
this.hiBitsFlag = this.getHB2Flag()[this.foundState.Symbol];
int index = rs.Freq - 1;
int num6 = this.minContext.getArrayIndex(this, rs);
int summ = this.binSumm[index][num6];
if (decoder.DecodeBit((uint)summ, 14) == 0)
{
this.binSumm[index][num6] = ((summ + INTERVAL) - this.minContext.getMean(summ, 7, 2)) & 0xffff;
this.foundState.Address = rs.Address;
symbol = (byte)rs.Symbol;
rs.IncrementFreq((rs.Freq < 0x80) ? 1 : 0);
this.prevSuccess = 1;
this.incRunLength(1);
this.nextContext();
return(symbol);
}
summ = (summ - this.minContext.getMean(summ, 7, 2)) & 0xffff;
this.binSumm[index][num6] = summ;
this.initEsc = PPMContext.ExpEscape[Utility.URShift(summ, 10)];
for (num = 0; num < 0x100; num++)
{
this.charMask[num] = -1;
}
this.charMask[rs.Symbol] = 0;
this.prevSuccess = 0;
}
while (true)
{
int num8;
state = this.tempState1.Initialize(this.Heap);
int numStats = this.minContext.NumStats;
do
{
this.orderFall++;
this.minContext.Address = this.minContext.getSuffix();
if ((this.minContext.Address <= this.subAlloc.PText) || (this.minContext.Address > this.subAlloc.HeapEnd))
{
return(-1);
}
}while (this.minContext.NumStats == numStats);
num3 = 0;
state.Address = this.minContext.FreqData.GetStats();
num = 0;
int num9 = this.minContext.NumStats - numStats;
do
{
int num11 = this.charMask[state.Symbol];
num3 += state.Freq & num11;
this.minContext.ps[num] = state.Address;
state.IncrementAddress();
num -= num11;
}while (num != num9);
SEE2Context context = this.minContext.makeEscFreq(this, numStats, out num8);
num8 += num3;
threshold = (int)decoder.GetThreshold((uint)num8);
if (threshold < num3)
{
SharpCompress.Compressor.PPMd.H.State state3 = this.tempState2.Initialize(this.Heap);
num3 = 0;
num = 0;
state3.Address = this.minContext.ps[num];
while ((num3 += state3.Freq) <= threshold)
{
num++;
state3.Address = this.minContext.ps[num];
}
state.Address = state3.Address;
decoder.Decode((uint)(num3 - state.Freq), (uint)state.Freq);
context.update();
symbol = (byte)state.Symbol;
this.minContext.update2(this, state.Address);
this.updateModel();
return(symbol);
}
if (threshold >= num8)
{
return(-2);
}
decoder.Decode((uint)num3, (uint)(num8 - num3));
context.Summ += num8;
do
{
state.Address = this.minContext.ps[--num];
this.charMask[state.Symbol] = 0;
}while (num != 0);
}
}
