PPMContext.java
/*
* Copyright (c) 2007 innoSysTec (R) GmbH, Germany. All rights reserved.
* Original author: Edmund Wagner
* Creation date: 31.05.2007
*
* Source: $HeadURL$
* Last changed: $LastChangedDate$
*
* the unrar licence applies to all junrar source and binary distributions
* you are not allowed to use this source to re-create the RAR compression algorithm
*
* Here some html entities which can be used for escaping javadoc tags:
* "&": "&" or "&"
* "<": "<" or "<"
* ">": ">" or ">"
* "@": "@"
*/
package com.github.junrar.unpack.ppm;
import com.github.junrar.io.Raw;
/**
* DOCUMENT ME
*
* @author $LastChangedBy$
* @version $LastChangedRevision$
*/
public class PPMContext extends Pointer {
private static final int unionSize = Math.max(FreqData.size, State.size);
public static final int size = 2 + unionSize + 4; // 12
// ushort NumStats;
private int numStats; // determines if feqData or onstate is used
// (1==onestate)
private final FreqData freqData; // -\
// |-> union
private final State oneState; // -/
private int suffix; // pointer ppmcontext
public static final int[] ExpEscape = {25, 14, 9, 7, 5, 5, 4, 4, 4, 3, 3, 3, 2, 2, 2, 2 };
// Temp fields
private final State tempState1 = new State(null);
private final State tempState2 = new State(null);
private final State tempState3 = new State(null);
private final State tempState4 = new State(null);
private final State tempState5 = new State(null);
private PPMContext tempPPMContext = null;
private final int[] ps = new int[256];
public PPMContext(byte[] mem) {
super(mem);
oneState = new State(mem);
freqData = new FreqData(mem);
}
public PPMContext init(byte[] mem) {
this.mem = mem;
pos = 0;
oneState.init(mem);
freqData.init(mem);
return this;
}
public FreqData getFreqData() {
return freqData;
}
public void setFreqData(FreqData freqData) {
this.freqData.setSummFreq(freqData.getSummFreq());
this.freqData.setStats(freqData.getStats());
}
public final int getNumStats() {
if (mem != null) {
numStats = Raw.readShortLittleEndian(mem, pos) & 0xffff;
}
return numStats;
}
public final void setNumStats(int numStats) {
this.numStats = numStats & 0xffff;
if (mem != null) {
Raw.writeShortLittleEndian(mem, pos, (short) numStats);
}
}
public State getOneState() {
return oneState;
}
public void setOneState(StateRef oneState) {
this.oneState.setValues(oneState);
}
public int getSuffix() {
if (mem != null) {
suffix = Raw.readIntLittleEndian(mem, pos + 8);
}
return suffix;
}
public void setSuffix(PPMContext suffix) {
setSuffix(suffix.getAddress());
}
public void setSuffix(int suffix) {
this.suffix = suffix;
if (mem != null) {
Raw.writeIntLittleEndian(mem, pos + 8, suffix);
}
}
@Override
public void setAddress(int pos) {
super.setAddress(pos);
oneState.setAddress(pos + 2);
freqData.setAddress(pos + 2);
}
private PPMContext getTempPPMContext(byte[] mem) {
if (tempPPMContext == null) {
tempPPMContext = new PPMContext(null);
}
return tempPPMContext.init(mem);
}
public int createChild(ModelPPM model, State pStats/* ptr */,
StateRef firstState /* ref */) {
PPMContext pc = getTempPPMContext(model.getSubAlloc().getHeap());
pc.setAddress(model.getSubAlloc().allocContext());
if (pc != null) {
pc.setNumStats(1);
pc.setOneState(firstState);
pc.setSuffix(this);
pStats.setSuccessor(pc);
}
return pc.getAddress();
}
public void rescale(ModelPPM model) {
int OldNS = getNumStats(), i = getNumStats() - 1, Adder, EscFreq;
// STATE* p1, * p;
State p1 = new State(model.getHeap());
State p = new State(model.getHeap());
State temp = new State(model.getHeap());
for (p.setAddress(model.getFoundState().getAddress());
p.getAddress() != freqData.getStats();
p.decAddress()) {
temp.setAddress(p.getAddress() - State.size);
State.ppmdSwap(p, temp);
}
temp.setAddress(freqData.getStats());
temp.incFreq(4);
freqData.incSummFreq(4);
EscFreq = freqData.getSummFreq() - p.getFreq();
Adder = (model.getOrderFall() != 0) ? 1 : 0;
p.setFreq((p.getFreq() + Adder) >>> 1);
freqData.setSummFreq(p.getFreq());
do {
p.incAddress();
EscFreq -= p.getFreq();
p.setFreq((p.getFreq() + Adder) >>> 1);
freqData.incSummFreq(p.getFreq());
temp.setAddress(p.getAddress() - State.size);
if (p.getFreq() > temp.getFreq()) {
p1.setAddress(p.getAddress());
StateRef tmp = new StateRef();
tmp.setValues(p1);
State temp2 = new State(model.getHeap());
State temp3 = new State(model.getHeap());
do {
// p1[0]=p1[-1];
temp2.setAddress(p1.getAddress() - State.size);
p1.setValues(temp2);
p1.decAddress();
temp3.setAddress(p1.getAddress() - State.size);
} while (p1.getAddress() != freqData.getStats() && tmp.getFreq() > temp3.getFreq());
p1.setValues(tmp);
}
} while (--i != 0);
if (p.getFreq() == 0) {
do {
i++;
p.decAddress();
} while (p.getFreq() == 0);
EscFreq += i;
setNumStats(getNumStats() - i);
if (getNumStats() == 1) {
StateRef tmp = new StateRef();
temp.setAddress(freqData.getStats());
tmp.setValues(temp);
// STATE tmp=*U.Stats;
do {
// tmp.Freq-=(tmp.Freq >> 1)
tmp.decFreq(tmp.getFreq() >>> 1);
EscFreq >>>= 1;
} while (EscFreq > 1);
model.getSubAlloc().freeUnits(freqData.getStats(), (OldNS + 1) >>> 1);
oneState.setValues(tmp);
model.getFoundState().setAddress(oneState.getAddress());
return;
}
}
EscFreq -= EscFreq >>> 1;
freqData.incSummFreq(EscFreq);
int n0 = (OldNS + 1) >>> 1, n1 = (getNumStats() + 1) >>> 1;
if (n0 != n1) {
freqData.setStats(model.getSubAlloc().shrinkUnits(freqData.getStats(), n0, n1));
}
model.getFoundState().setAddress(freqData.getStats());
}
private int getArrayIndex(ModelPPM Model, State rs) {
PPMContext tempSuffix = getTempPPMContext(Model.getSubAlloc().getHeap());
tempSuffix.setAddress(getSuffix());
int ret = 0;
ret += Model.getPrevSuccess();
ret += Model.getNS2BSIndx()[tempSuffix.getNumStats() - 1];
ret += Model.getHiBitsFlag() + 2 * Model.getHB2Flag()[rs.getSymbol()];
ret += ((Model.getRunLength() >>> 26) & 0x20);
return ret;
}
public int getMean(int summ, int shift, int round) {
return ((summ + (1 << (shift - round))) >>> (shift));
}
public void decodeBinSymbol(ModelPPM model) {
State rs = tempState1.init(model.getHeap());
rs.setAddress(oneState.getAddress()); // State&
model.setHiBitsFlag(model.getHB2Flag()[model.getFoundState().getSymbol()]);
int off1 = rs.getFreq() - 1;
int off2 = getArrayIndex(model, rs);
int bs = model.getBinSumm()[off1][off2];
if (model.getCoder().getCurrentShiftCount(ModelPPM.TOT_BITS) < bs) {
model.getFoundState().setAddress(rs.getAddress());
rs.incFreq((rs.getFreq() < 128) ? 1 : 0);
model.getCoder().getSubRange().setLowCount(0);
model.getCoder().getSubRange().setHighCount(bs);
bs = ((bs + ModelPPM.INTERVAL - getMean(bs, ModelPPM.PERIOD_BITS, 2)) & 0xffff);
model.getBinSumm()[off1][off2] = bs;
model.setPrevSuccess(1);
model.incRunLength(1);
} else {
model.getCoder().getSubRange().setLowCount(bs);
bs = (bs - getMean(bs, ModelPPM.PERIOD_BITS, 2)) & 0xFFFF;
model.getBinSumm()[off1][off2] = bs;
model.getCoder().getSubRange().setHighCount(ModelPPM.BIN_SCALE);
model.setInitEsc(ExpEscape[bs >>> 10]);
model.setNumMasked(1);
model.getCharMask()[rs.getSymbol()] = model.getEscCount();
model.setPrevSuccess(0);
model.getFoundState().setAddress(0);
}
//int a = 0;//TODO just 4 debugging
}
// public static void ppmdSwap(ModelPPM model, StatePtr state1, StatePtr state2)
// {
// byte[] bytes = model.getSubAlloc().getHeap();
// int p1 = state1.getAddress();
// int p2 = state2.getAddress();
//
// for (int i = 0; i < StatePtr.size; i++) {
// byte temp = bytes[p1+i];
// bytes[p1+i] = bytes[p2+i];
// bytes[p2+i] = temp;
// }
// state1.setAddress(p1);
// state2.setAddress(p2);
// }
public void update1(ModelPPM model, int p/* ptr */) {
model.getFoundState().setAddress(p);
model.getFoundState().incFreq(4);
freqData.incSummFreq(4);
State p0 = tempState3.init(model.getHeap());
State p1 = tempState4.init(model.getHeap());
p0.setAddress(p);
p1.setAddress(p - State.size);
if (p0.getFreq() > p1.getFreq()) {
State.ppmdSwap(p0, p1);
model.getFoundState().setAddress(p1.getAddress());
if (p1.getFreq() > ModelPPM.MAX_FREQ) {
rescale(model);
}
}
}
public boolean decodeSymbol2(ModelPPM model) {
long count;
int hiCnt, i = getNumStats() - model.getNumMasked();
SEE2Context psee2c = makeEscFreq2(model, i);
RangeCoder coder = model.getCoder();
// STATE* ps[256], ** pps=ps, * p=U.Stats-1;
State p = tempState1.init(model.getHeap());
State temp = tempState2.init(model.getHeap());
p.setAddress(freqData.getStats() - State.size);
int pps = 0;
hiCnt = 0;
do {
do {
p.incAddress(); // p++;
} while (model.getCharMask()[p.getSymbol()] == model.getEscCount());
hiCnt += p.getFreq();
ps[pps++] = p.getAddress();
} while (--i != 0);
coder.getSubRange().incScale(hiCnt);
count = coder.getCurrentCount();
if (count >= coder.getSubRange().getScale()) {
return false;
}
pps = 0;
p.setAddress(ps[pps]);
if (count < hiCnt) {
hiCnt = 0;
while ((hiCnt += p.getFreq()) <= count) {
p.setAddress(ps[++pps]); // p=*++pps;
}
coder.getSubRange().setHighCount(hiCnt);
coder.getSubRange().setLowCount(hiCnt - p.getFreq());
psee2c.update();
update2(model, p.getAddress());
} else {
coder.getSubRange().setLowCount(hiCnt);
coder.getSubRange().setHighCount(coder.getSubRange().getScale());
i = getNumStats() - model.getNumMasked(); // ->NumMasked;
pps--;
do {
temp.setAddress(ps[++pps]); // (*++pps)
model.getCharMask()[temp.getSymbol()] = model.getEscCount();
} while (--i != 0);
psee2c.incSumm((int) coder.getSubRange().getScale());
model.setNumMasked(getNumStats());
}
return (true);
}
public void update2(ModelPPM model, int p/* state ptr */) {
State temp = tempState5.init(model.getHeap());
temp.setAddress(p);
model.getFoundState().setAddress(p);
model.getFoundState().incFreq(4);
freqData.incSummFreq(4);
if (temp.getFreq() > ModelPPM.MAX_FREQ) {
rescale(model);
}
model.incEscCount(1);
model.setRunLength(model.getInitRL());
}
private SEE2Context makeEscFreq2(ModelPPM model, int Diff) {
SEE2Context psee2c;
int numStats = getNumStats();
if (numStats != 256) {
PPMContext suff = getTempPPMContext(model.getHeap());
suff.setAddress(getSuffix());
int idx1 = model.getNS2Indx()[Diff - 1];
int idx2 = 0;
idx2 += (Diff < suff.getNumStats() - numStats) ? 1 : 0;
idx2 += 2 * ((freqData.getSummFreq() < 11 * numStats) ? 1 : 0);
idx2 += 4 * ((model.getNumMasked() > Diff) ? 1 : 0);
idx2 += model.getHiBitsFlag();
psee2c = model.getSEE2Cont()[idx1][idx2];
model.getCoder().getSubRange().setScale(psee2c.getMean());
} else {
psee2c = model.getDummySEE2Cont();
model.getCoder().getSubRange().setScale(1);
}
return psee2c;
}
public boolean decodeSymbol1(ModelPPM model) {
RangeCoder coder = model.getCoder();
coder.getSubRange().setScale(freqData.getSummFreq());
State p = new State(model.getHeap());
p.setAddress(freqData.getStats());
int i, HiCnt;
long count = coder.getCurrentCount();
if (count >= coder.getSubRange().getScale()) {
return false;
}
if (count < (HiCnt = p.getFreq())) {
coder.getSubRange().setHighCount(HiCnt);
model.setPrevSuccess((2 * HiCnt > coder.getSubRange().getScale()) ? 1 : 0);
model.incRunLength(model.getPrevSuccess());
HiCnt += 4;
model.getFoundState().setAddress(p.getAddress());
model.getFoundState().setFreq(HiCnt);
freqData.incSummFreq(4);
if (HiCnt > ModelPPM.MAX_FREQ) {
rescale(model);
}
coder.getSubRange().setLowCount(0);
return true;
} else {
if (model.getFoundState().getAddress() == 0) {
return (false);
}
}
model.setPrevSuccess(0);
int numStats = getNumStats();
i = numStats - 1;
while ((HiCnt += p.incAddress().getFreq()) <= count) {
if (--i == 0) {
model.setHiBitsFlag(model.getHB2Flag()[model.getFoundState().getSymbol()]);
coder.getSubRange().setLowCount(HiCnt);
model.getCharMask()[p.getSymbol()] = model.getEscCount();
model.setNumMasked(numStats);
i = numStats - 1;
model.getFoundState().setAddress(0);
do {
model.getCharMask()[p.decAddress().getSymbol()] = model.getEscCount();
} while (--i != 0);
coder.getSubRange().setHighCount(coder.getSubRange().getScale());
return (true);
}
}
coder.getSubRange().setLowCount(HiCnt - p.getFreq());
coder.getSubRange().setHighCount(HiCnt);
update1(model, p.getAddress());
return (true);
}
public String toString() {
StringBuilder buffer = new StringBuilder();
buffer.append("PPMContext[");
buffer.append("\n pos=");
buffer.append(pos);
buffer.append("\n size=");
buffer.append(size);
buffer.append("\n numStats=");
buffer.append(getNumStats());
buffer.append("\n Suffix=");
buffer.append(getSuffix());
buffer.append("\n freqData=");
buffer.append(freqData);
buffer.append("\n oneState=");
buffer.append(oneState);
buffer.append("\n]");
return buffer.toString();
}
}