Class: Omnizip::Algorithms::LZMA::XzProbabilityModels

Inherits:
Object
  • Object
show all
Includes:
Constants
Defined in:
lib/omnizip/algorithms/lzma/xz_probability_models.rb

Overview

XZ Utils-compatible probability models

Organizes all probability models used by LZMA encoder, matching XZ Utils structure exactly. All models start at probability 1024 (BIT_MODEL_TOTAL / 2 = 0.5 probability).

Uses XzBufferedRangeEncoder::Probability for mutable inline updates.

Based on: xz/src/liblzma/lzma/lzma_encoder_private.h

Constant Summary

Constants included from Constants

Constants::BIT_MODEL_TOTAL, Constants::COMPRESSION_LEVEL_DEFAULT, Constants::COMPRESSION_LEVEL_MAX, Constants::COMPRESSION_LEVEL_MIN, Constants::DICT_SIZE_MAX, Constants::DICT_SIZE_MIN, Constants::DIST_ALIGN_BITS, Constants::DIST_ALIGN_SIZE, Constants::DIST_SLOT_FAST_LIMIT, Constants::END_POS_MODEL_INDEX, Constants::EOS_MARKER, Constants::INIT_PROBS, Constants::LEN_HIGH_SYMBOLS, Constants::LEN_LOW_SYMBOLS, Constants::LEN_MID_SYMBOLS, Constants::LIT_SIZE_MAX, Constants::MATCH_LEN_MAX, Constants::MATCH_LEN_MIN, Constants::MOVE_BITS, Constants::NUM_DIRECT_BITS, Constants::NUM_DIST_SLOTS, Constants::NUM_DIST_SLOT_BITS, Constants::NUM_FULL_DISTANCES, Constants::NUM_LEN_HIGH_BITS, Constants::NUM_LEN_LOW_BITS, Constants::NUM_LEN_MID_BITS, Constants::NUM_LEN_TO_POS_STATES, Constants::NUM_LIT_CONTEXT_BITS_MAX, Constants::NUM_LIT_POS_BITS_MAX, Constants::NUM_POS_BITS_MAX, Constants::NUM_STATES, Constants::POS_STATES_MAX, Constants::START_POS_MODEL_INDEX, Constants::TOP

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(lc, lp, pb) ⇒ XzProbabilityModels

Initialize all probability models

Parameters:

  • lc (Integer) —

    Number of literal context bits (0-8)

  • lp (Integer) —

    Number of literal position bits (0-4)

  • pb (Integer) —

    Number of position bits (0-4)



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 36

def initialize(lc, lp, pb)
  @lc = lc
  @lp = lp
  @pb = pb

  init_literal_models(lc, lp)
  init_match_models(pb)
  init_distance_models
  init_length_encoders(pb)
end

Instance Attribute Details

#dist_align ⇒ Object (readonly)

Distance models



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 26

def dist_align
  @dist_align
end

#dist_slot ⇒ Object (readonly)

Distance models



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 26

def dist_slot
  @dist_slot
end

#dist_special ⇒ Object (readonly)

Distance models



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 26

def dist_special
  @dist_special
end

#is_match ⇒ Object (readonly)

Match type models



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 22

def is_match
  @is_match
end

#is_rep ⇒ Object (readonly)

Match type models



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 22

def is_rep
  @is_rep
end

#is_rep0 ⇒ Object (readonly)

Match type models



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 22

def is_rep0
  @is_rep0
end

#is_rep0_long ⇒ Object (readonly)

Returns the value of attribute is_rep0_long.



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 23

def is_rep0_long
  @is_rep0_long
end

#is_rep1 ⇒ Object (readonly)

Match type models



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 22

def is_rep1
  @is_rep1
end

#is_rep2 ⇒ Object (readonly)

Match type models



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 22

def is_rep2
  @is_rep2
end

#literal ⇒ Object (readonly)

Literal context models



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 19

def literal
  @literal
end

#match_len_encoder ⇒ Object (readonly)

Length encoders



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 29

def match_len_encoder
  @match_len_encoder
end

#rep_len_encoder ⇒ Object (readonly)

Length encoders



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 29

def rep_len_encoder
  @rep_len_encoder
end

Instance Method Details

#reset ⇒ Object

Reset all probability models to initial state



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# File 'lib/omnizip/algorithms/lzma/xz_probability_models.rb', line 48

def reset
  reset_literal_models
  reset_match_models
  reset_distance_models
  reset_length_encoders
end