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| author | Matt A. Tobin <mattatobin@localhost.localdomain> | 2018-02-02 04:16:08 -0500 |
|---|---|---|
| committer | Matt A. Tobin <mattatobin@localhost.localdomain> | 2018-02-02 04:16:08 -0500 |
| commit | 5f8de423f190bbb79a62f804151bc24824fa32d8 (patch) | |
| tree | 10027f336435511475e392454359edea8e25895d /other-licenses/7zstub/src/7zip/Compress/RangeCoder/RangeCoderBit.h | |
| parent | 49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff) | |
| download | UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.gz UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.lz UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.tar.xz UXP-5f8de423f190bbb79a62f804151bc24824fa32d8.zip | |
Add m-esr52 at 52.6.0
Diffstat (limited to 'other-licenses/7zstub/src/7zip/Compress/RangeCoder/RangeCoderBit.h')
| -rw-r--r-- | other-licenses/7zstub/src/7zip/Compress/RangeCoder/RangeCoderBit.h | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/other-licenses/7zstub/src/7zip/Compress/RangeCoder/RangeCoderBit.h b/other-licenses/7zstub/src/7zip/Compress/RangeCoder/RangeCoderBit.h new file mode 100644 index 000000000..64538e687 --- /dev/null +++ b/other-licenses/7zstub/src/7zip/Compress/RangeCoder/RangeCoderBit.h @@ -0,0 +1,120 @@ +// Compress/RangeCoder/RangeCoderBit.h
+
+#ifndef __COMPRESS_RANGECODER_BIT_H
+#define __COMPRESS_RANGECODER_BIT_H
+
+#include "RangeCoder.h"
+
+namespace NCompress {
+namespace NRangeCoder {
+
+const int kNumBitModelTotalBits = 11;
+const UInt32 kBitModelTotal = (1 << kNumBitModelTotalBits);
+
+const int kNumMoveReducingBits = 2;
+
+const int kNumBitPriceShiftBits = 6;
+const UInt32 kBitPrice = 1 << kNumBitPriceShiftBits;
+
+class CPriceTables
+{
+public:
+ static UInt32 ProbPrices[kBitModelTotal >> kNumMoveReducingBits];
+ static void Init();
+ CPriceTables();
+};
+
+template <int numMoveBits>
+class CBitModel
+{
+public:
+ UInt32 Prob;
+ void UpdateModel(UInt32 symbol)
+ {
+ /*
+ Prob -= (Prob + ((symbol - 1) & ((1 << numMoveBits) - 1))) >> numMoveBits;
+ Prob += (1 - symbol) << (kNumBitModelTotalBits - numMoveBits);
+ */
+ if (symbol == 0)
+ Prob += (kBitModelTotal - Prob) >> numMoveBits;
+ else
+ Prob -= (Prob) >> numMoveBits;
+ }
+public:
+ void Init() { Prob = kBitModelTotal / 2; }
+};
+
+template <int numMoveBits>
+class CBitEncoder: public CBitModel<numMoveBits>
+{
+public:
+ void Encode(CEncoder *encoder, UInt32 symbol)
+ {
+ /*
+ encoder->EncodeBit(this->Prob, kNumBitModelTotalBits, symbol);
+ this->UpdateModel(symbol);
+ */
+ UInt32 newBound = (encoder->Range >> kNumBitModelTotalBits) * this->Prob;
+ if (symbol == 0)
+ {
+ encoder->Range = newBound;
+ this->Prob += (kBitModelTotal - this->Prob) >> numMoveBits;
+ }
+ else
+ {
+ encoder->Low += newBound;
+ encoder->Range -= newBound;
+ this->Prob -= (this->Prob) >> numMoveBits;
+ }
+ if (encoder->Range < kTopValue)
+ {
+ encoder->Range <<= 8;
+ encoder->ShiftLow();
+ }
+ }
+ UInt32 GetPrice(UInt32 symbol) const
+ {
+ return CPriceTables::ProbPrices[
+ (((this->Prob - symbol) ^ ((-(int)symbol))) & (kBitModelTotal - 1)) >> kNumMoveReducingBits];
+ }
+ UInt32 GetPrice0() const { return CPriceTables::ProbPrices[this->Prob >> kNumMoveReducingBits]; }
+ UInt32 GetPrice1() const { return CPriceTables::ProbPrices[(kBitModelTotal - this->Prob) >> kNumMoveReducingBits]; }
+};
+
+
+template <int numMoveBits>
+class CBitDecoder: public CBitModel<numMoveBits>
+{
+public:
+ UInt32 Decode(CDecoder *decoder)
+ {
+ UInt32 newBound = (decoder->Range >> kNumBitModelTotalBits) * this->Prob;
+ if (decoder->Code < newBound)
+ {
+ decoder->Range = newBound;
+ this->Prob += (kBitModelTotal - this->Prob) >> numMoveBits;
+ if (decoder->Range < kTopValue)
+ {
+ decoder->Code = (decoder->Code << 8) | decoder->Stream.ReadByte();
+ decoder->Range <<= 8;
+ }
+ return 0;
+ }
+ else
+ {
+ decoder->Range -= newBound;
+ decoder->Code -= newBound;
+ this->Prob -= (this->Prob) >> numMoveBits;
+ if (decoder->Range < kTopValue)
+ {
+ decoder->Code = (decoder->Code << 8) | decoder->Stream.ReadByte();
+ decoder->Range <<= 8;
+ }
+ return 1;
+ }
+ }
+};
+
+}}
+
+#endif
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