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| author | Michele Calgaro <michele.calgaro@yahoo.it> | 2024-06-07 23:30:05 +0900 |
|---|---|---|
| committer | Michele Calgaro <michele.calgaro@yahoo.it> | 2024-06-07 23:30:05 +0900 |
| commit | 17b259df9cb6b28779d4881b2b6c805ee2e48eea (patch) | |
| tree | 5ed61937459cb7081089111b0242c01ec178f1f3 /reader/src/formats/chm/HuffmanDecoder.cpp | |
| parent | 1cba8bce178eb2d6719c6f7f21e2c9352c5513a6 (diff) | |
| download | tde-ebook-reader-17b259df9cb6b28779d4881b2b6c805ee2e48eea.tar.gz tde-ebook-reader-17b259df9cb6b28779d4881b2b6c805ee2e48eea.zip | |
Rename to tde-ebook-reader
Signed-off-by: Michele Calgaro <michele.calgaro@yahoo.it>
Diffstat (limited to 'reader/src/formats/chm/HuffmanDecoder.cpp')
| -rw-r--r-- | reader/src/formats/chm/HuffmanDecoder.cpp | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/reader/src/formats/chm/HuffmanDecoder.cpp b/reader/src/formats/chm/HuffmanDecoder.cpp new file mode 100644 index 0000000..db8718f --- /dev/null +++ b/reader/src/formats/chm/HuffmanDecoder.cpp @@ -0,0 +1,60 @@ +/* + * Copyright (C) 2004-2012 Geometer Plus <contact@geometerplus.com> + * + * 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. + */ + +#include <algorithm> + +#include "HuffmanDecoder.h" + +HuffmanDecoder::HuffmanDecoder() : myMaxBitsNumber(0) { +} + +void HuffmanDecoder::reset() { + CodeLengths.clear(); +} + +bool HuffmanDecoder::buildTable() { + myMaxBitsNumber = 0; + for (unsigned short symbol = 0; symbol < CodeLengths.size(); symbol++) { + myMaxBitsNumber = std::max(CodeLengths[symbol], myMaxBitsNumber); + } + if (myMaxBitsNumber > 16) { + return false; + } + + unsigned int tableSize = 1 << myMaxBitsNumber; + mySymbols.clear(); + mySymbols.reserve(tableSize); + + for (unsigned char i = 1; i <= myMaxBitsNumber; ++i) { + for (unsigned short symbol = 0; symbol < CodeLengths.size(); symbol++) { + if (CodeLengths[symbol] == i) { + mySymbols.insert(mySymbols.end(), 1 << (myMaxBitsNumber - i), symbol); + if (mySymbols.size() > tableSize) { + return false; + } + } + } + } + + if (mySymbols.size() < tableSize) { + mySymbols.insert(mySymbols.end(), tableSize - mySymbols.size(), 0); + } + + return true; +} |
