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author | 2015-01-11 08:10:25 +0100 | |
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committer | 2015-01-11 08:10:25 +0100 | |
commit | 6a23c2f3b766cf4fc7028628f76b5ff9396383f0 (patch) | |
tree | a01e16637118ae0c80f337119898bdf18f081e24 /3rdparty/lzma/Java/SevenZip/Compression/RangeCoder/BitTreeDecoder.java | |
parent | 45ac9b351e0076c371de4c7453f59567b27b1cb6 (diff) |
Added full lzma sdk source (nw)
Diffstat (limited to '3rdparty/lzma/Java/SevenZip/Compression/RangeCoder/BitTreeDecoder.java')
-rw-r--r-- | 3rdparty/lzma/Java/SevenZip/Compression/RangeCoder/BitTreeDecoder.java | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/3rdparty/lzma/Java/SevenZip/Compression/RangeCoder/BitTreeDecoder.java b/3rdparty/lzma/Java/SevenZip/Compression/RangeCoder/BitTreeDecoder.java new file mode 100644 index 00000000000..76985814519 --- /dev/null +++ b/3rdparty/lzma/Java/SevenZip/Compression/RangeCoder/BitTreeDecoder.java @@ -0,0 +1,55 @@ +package SevenZip.Compression.RangeCoder; + +public class BitTreeDecoder +{ + short[] Models; + int NumBitLevels; + + public BitTreeDecoder(int numBitLevels) + { + NumBitLevels = numBitLevels; + Models = new short[1 << numBitLevels]; + } + + public void Init() + { + Decoder.InitBitModels(Models); + } + + public int Decode(Decoder rangeDecoder) throws java.io.IOException + { + int m = 1; + for (int bitIndex = NumBitLevels; bitIndex != 0; bitIndex--) + m = (m << 1) + rangeDecoder.DecodeBit(Models, m); + return m - (1 << NumBitLevels); + } + + public int ReverseDecode(Decoder rangeDecoder) throws java.io.IOException + { + int m = 1; + int symbol = 0; + for (int bitIndex = 0; bitIndex < NumBitLevels; bitIndex++) + { + int bit = rangeDecoder.DecodeBit(Models, m); + m <<= 1; + m += bit; + symbol |= (bit << bitIndex); + } + return symbol; + } + + public static int ReverseDecode(short[] Models, int startIndex, + Decoder rangeDecoder, int NumBitLevels) throws java.io.IOException + { + int m = 1; + int symbol = 0; + for (int bitIndex = 0; bitIndex < NumBitLevels; bitIndex++) + { + int bit = rangeDecoder.DecodeBit(Models, startIndex + m); + m <<= 1; + m += bit; + symbol |= (bit << bitIndex); + } + return symbol; + } +} |