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diff --git a/common/huffman.cpp b/common/huffman.cpp
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+/* ScummVM - Graphic Adventure Engine
+ *
+ * ScummVM is the legal property of its developers, whose names
+ * are too numerous to list here. Please refer to the COPYRIGHT
+ * file distributed with this source distribution.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ */
+
+// Based on eos' Huffman code
+
+#include "common/huffman.h"
+#include "common/util.h"
+#include "common/textconsole.h"
+#include "common/bitstream.h"
+
+namespace Common {
+
+Huffman::Symbol::Symbol(uint32 c, uint32 s) : code(c), symbol(s) {
+}
+
+
+Huffman::Huffman(uint8 maxLength, uint32 codeCount, const uint32 *codes, const uint8 *lengths, const uint32 *symbols) {
+ assert(codeCount > 0);
+
+ assert(codes);
+ assert(lengths);
+
+ if (maxLength == 0)
+ for (uint32 i = 0; i < codeCount; i++)
+ maxLength = MAX(maxLength, lengths[i]);
+
+ assert(maxLength <= 32);
+
+ _codes.resize(maxLength);
+ _symbols.resize(codeCount);
+
+ for (uint32 i = 0; i < codeCount; i++) {
+ // The symbol. If none were specified, just assume it's identical to the code index
+ uint32 symbol = symbols ? symbols[i] : i;
+
+ // Put the code and symbol into the correct list
+ _codes[lengths[i] - 1].push_back(Symbol(codes[i], symbol));
+
+ // And put the pointer to the symbol/code struct into the symbol list.
+ _symbols[i] = &_codes[lengths[i] - 1].back();
+ }
+}
+
+Huffman::~Huffman() {
+}
+
+void Huffman::setSymbols(const uint32 *symbols) {
+ for (uint32 i = 0; i < _symbols.size(); i++)
+ _symbols[i]->symbol = symbols ? *symbols++ : i;
+}
+
+uint32 Huffman::getSymbol(BitStream &bits) const {
+ uint32 code = 0;
+
+ for (uint32 i = 0; i < _codes.size(); i++) {
+ bits.addBit(code, i);
+
+ for (CodeList::const_iterator cCode = _codes[i].begin(); cCode != _codes[i].end(); ++cCode)
+ if (code == cCode->code)
+ return cCode->symbol;
+ }
+
+ error("Unknown Huffman code");
+ return 0;
+}
+
+} // End of namespace Common