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diff --git a/kpdf/xpdf/xpdf/JArithmeticDecoder.cc b/kpdf/xpdf/xpdf/JArithmeticDecoder.cc
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+//========================================================================
+//
+// JArithmeticDecoder.cc
+//
+// Copyright 2002-2004 Glyph & Cog, LLC
+//
+//========================================================================
+
+#include <aconf.h>
+
+#ifdef USE_GCC_PRAGMAS
+#pragma implementation
+#endif
+
+#include "Object.h"
+#include "Stream.h"
+#include "JArithmeticDecoder.h"
+
+//------------------------------------------------------------------------
+// JArithmeticDecoderStates
+//------------------------------------------------------------------------
+
+JArithmeticDecoderStats::JArithmeticDecoderStats(int contextSizeA) {
+ contextSize = contextSizeA;
+ cxTab = (Guchar *)gmallocn(contextSize, sizeof(Guchar));
+ reset();
+}
+
+JArithmeticDecoderStats::~JArithmeticDecoderStats() {
+ gfree(cxTab);
+}
+
+JArithmeticDecoderStats *JArithmeticDecoderStats::copy() {
+ JArithmeticDecoderStats *stats;
+
+ stats = new JArithmeticDecoderStats(contextSize);
+ memcpy(stats->cxTab, cxTab, contextSize);
+ return stats;
+}
+
+void JArithmeticDecoderStats::reset() {
+ memset(cxTab, 0, contextSize);
+}
+
+void JArithmeticDecoderStats::copyFrom(JArithmeticDecoderStats *stats) {
+ memcpy(cxTab, stats->cxTab, contextSize);
+}
+
+void JArithmeticDecoderStats::setEntry(Guint cx, int i, int mps) {
+ cxTab[cx] = (i << 1) + mps;
+}
+
+//------------------------------------------------------------------------
+// JArithmeticDecoder
+//------------------------------------------------------------------------
+
+Guint JArithmeticDecoder::qeTab[47] = {
+ 0x56010000, 0x34010000, 0x18010000, 0x0AC10000,
+ 0x05210000, 0x02210000, 0x56010000, 0x54010000,
+ 0x48010000, 0x38010000, 0x30010000, 0x24010000,
+ 0x1C010000, 0x16010000, 0x56010000, 0x54010000,
+ 0x51010000, 0x48010000, 0x38010000, 0x34010000,
+ 0x30010000, 0x28010000, 0x24010000, 0x22010000,
+ 0x1C010000, 0x18010000, 0x16010000, 0x14010000,
+ 0x12010000, 0x11010000, 0x0AC10000, 0x09C10000,
+ 0x08A10000, 0x05210000, 0x04410000, 0x02A10000,
+ 0x02210000, 0x01410000, 0x01110000, 0x00850000,
+ 0x00490000, 0x00250000, 0x00150000, 0x00090000,
+ 0x00050000, 0x00010000, 0x56010000
+};
+
+int JArithmeticDecoder::nmpsTab[47] = {
+ 1, 2, 3, 4, 5, 38, 7, 8, 9, 10, 11, 12, 13, 29, 15, 16,
+ 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
+ 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 45, 46
+};
+
+int JArithmeticDecoder::nlpsTab[47] = {
+ 1, 6, 9, 12, 29, 33, 6, 14, 14, 14, 17, 18, 20, 21, 14, 14,
+ 15, 16, 17, 18, 19, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29,
+ 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 46
+};
+
+int JArithmeticDecoder::switchTab[47] = {
+ 1, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
+};
+
+JArithmeticDecoder::JArithmeticDecoder() {
+ str = NULL;
+ dataLen = 0;
+ limitStream = gFalse;
+}
+
+inline Guint JArithmeticDecoder::readByte() {
+ if (limitStream) {
+ --dataLen;
+ if (dataLen < 0) {
+ return 0xff;
+ }
+ }
+ return (Guint)str->getChar() & 0xff;
+}
+
+JArithmeticDecoder::~JArithmeticDecoder() {
+ cleanup();
+}
+
+void JArithmeticDecoder::start() {
+ buf0 = readByte();
+ buf1 = readByte();
+
+ // INITDEC
+ c = (buf0 ^ 0xff) << 16;
+ byteIn();
+ c <<= 7;
+ ct -= 7;
+ a = 0x80000000;
+}
+
+void JArithmeticDecoder::restart(int dataLenA) {
+ int oldDataLen;
+
+ oldDataLen = dataLen;
+ dataLen = dataLenA;
+ if (oldDataLen == -1) {
+ buf1 = readByte();
+ } else if (oldDataLen <= -2) {
+ buf0 = readByte();
+ buf1 = readByte();
+ }
+}
+
+void JArithmeticDecoder::cleanup() {
+ if (limitStream) {
+ while (dataLen > 0) {
+ buf0 = buf1;
+ buf1 = readByte();
+ }
+ }
+}
+
+int JArithmeticDecoder::decodeBit(Guint context,
+ JArithmeticDecoderStats *stats) {
+ int bit;
+ Guint qe;
+ int iCX, mpsCX;
+
+ iCX = stats->cxTab[context] >> 1;
+ mpsCX = stats->cxTab[context] & 1;
+ qe = qeTab[iCX];
+ a -= qe;
+ if (c < a) {
+ if (a & 0x80000000) {
+ bit = mpsCX;
+ } else {
+ // MPS_EXCHANGE
+ if (a < qe) {
+ bit = 1 - mpsCX;
+ if (switchTab[iCX]) {
+ stats->cxTab[context] = (nlpsTab[iCX] << 1) | (1 - mpsCX);
+ } else {
+ stats->cxTab[context] = (nlpsTab[iCX] << 1) | mpsCX;
+ }
+ } else {
+ bit = mpsCX;
+ stats->cxTab[context] = (nmpsTab[iCX] << 1) | mpsCX;
+ }
+ // RENORMD
+ do {
+ if (ct == 0) {
+ byteIn();
+ }
+ a <<= 1;
+ c <<= 1;
+ --ct;
+ } while (!(a & 0x80000000));
+ }
+ } else {
+ c -= a;
+ // LPS_EXCHANGE
+ if (a < qe) {
+ bit = mpsCX;
+ stats->cxTab[context] = (nmpsTab[iCX] << 1) | mpsCX;
+ } else {
+ bit = 1 - mpsCX;
+ if (switchTab[iCX]) {
+ stats->cxTab[context] = (nlpsTab[iCX] << 1) | (1 - mpsCX);
+ } else {
+ stats->cxTab[context] = (nlpsTab[iCX] << 1) | mpsCX;
+ }
+ }
+ a = qe;
+ // RENORMD
+ do {
+ if (ct == 0) {
+ byteIn();
+ }
+ a <<= 1;
+ c <<= 1;
+ --ct;
+ } while (!(a & 0x80000000));
+ }
+ return bit;
+}
+
+int JArithmeticDecoder::decodeByte(Guint context,
+ JArithmeticDecoderStats *stats) {
+ int byte;
+ int i;
+
+ byte = 0;
+ for (i = 0; i < 8; ++i) {
+ byte = (byte << 1) | decodeBit(context, stats);
+ }
+ return byte;
+}
+
+GBool JArithmeticDecoder::decodeInt(int *x, JArithmeticDecoderStats *stats) {
+ int s;
+ Guint v;
+ int i;
+
+ prev = 1;
+ s = decodeIntBit(stats);
+ if (decodeIntBit(stats)) {
+ if (decodeIntBit(stats)) {
+ if (decodeIntBit(stats)) {
+ if (decodeIntBit(stats)) {
+ if (decodeIntBit(stats)) {
+ v = 0;
+ for (i = 0; i < 32; ++i) {
+ v = (v << 1) | decodeIntBit(stats);
+ }
+ v += 4436;
+ } else {
+ v = 0;
+ for (i = 0; i < 12; ++i) {
+ v = (v << 1) | decodeIntBit(stats);
+ }
+ v += 340;
+ }
+ } else {
+ v = 0;
+ for (i = 0; i < 8; ++i) {
+ v = (v << 1) | decodeIntBit(stats);
+ }
+ v += 84;
+ }
+ } else {
+ v = 0;
+ for (i = 0; i < 6; ++i) {
+ v = (v << 1) | decodeIntBit(stats);
+ }
+ v += 20;
+ }
+ } else {
+ v = decodeIntBit(stats);
+ v = (v << 1) | decodeIntBit(stats);
+ v = (v << 1) | decodeIntBit(stats);
+ v = (v << 1) | decodeIntBit(stats);
+ v += 4;
+ }
+ } else {
+ v = decodeIntBit(stats);
+ v = (v << 1) | decodeIntBit(stats);
+ }
+
+ if (s) {
+ if (v == 0) {
+ return gFalse;
+ }
+ *x = -(int)v;
+ } else {
+ *x = (int)v;
+ }
+ return gTrue;
+}
+
+int JArithmeticDecoder::decodeIntBit(JArithmeticDecoderStats *stats) {
+ int bit;
+
+ bit = decodeBit(prev, stats);
+ if (prev < 0x100) {
+ prev = (prev << 1) | bit;
+ } else {
+ prev = (((prev << 1) | bit) & 0x1ff) | 0x100;
+ }
+ return bit;
+}
+
+Guint JArithmeticDecoder::decodeIAID(Guint codeLen,
+ JArithmeticDecoderStats *stats) {
+ Guint i;
+ int bit;
+
+ prev = 1;
+ for (i = 0; i < codeLen; ++i) {
+ bit = decodeBit(prev, stats);
+ prev = (prev << 1) | bit;
+ }
+ return prev - (1 << codeLen);
+}
+
+void JArithmeticDecoder::byteIn() {
+ if (buf0 == 0xff) {
+ if (buf1 > 0x8f) {
+ ct = 8;
+ } else {
+ buf0 = buf1;
+ buf1 = readByte();
+ c = c + 0xfe00 - (buf0 << 9);
+ ct = 7;
+ }
+ } else {
+ buf0 = buf1;
+ buf1 = readByte();
+ c = c + 0xff00 - (buf0 << 8);
+ ct = 8;
+ }
+}
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