diff -r ea891871f481 -r bb5522e88ab2 misc/libphysfs/lzma/Java/SevenZip/Compression/RangeCoder/BitTreeDecoder.java --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/misc/libphysfs/lzma/Java/SevenZip/Compression/RangeCoder/BitTreeDecoder.java Mon Apr 10 12:06:43 2017 -0400 @@ -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; + } +}