Class: Omnizip::Algorithms::Zstandard::FSE::Encoder::CState

Inherits:
Object
  • Object
show all
Defined in:
lib/omnizip/algorithms/zstandard/fse/encoder.rb

Overview

FSE encoder state (value in [table_size, 2*table_size)).

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(value, state_log) ⇒ CState

Returns a new instance of CState.



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# File 'lib/omnizip/algorithms/zstandard/fse/encoder.rb', line 501

def initialize(value, state_log)
  @value = value
  @state_log = state_log
end

Instance Attribute Details

#value ⇒ Object (readonly)

Returns the value of attribute value.



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# File 'lib/omnizip/algorithms/zstandard/fse/encoder.rb', line 499

def value
  @value
end

Class Method Details

.init2(table, symbol) ⇒ Object

Initialize to the baseline for the first symbol to encode (the last to decode); C FSE_initCState2. rubocop:disable-next Metrics/AbcSize



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# File 'lib/omnizip/algorithms/zstandard/fse/encoder.rb', line 509

def self.init2(table, symbol)
  s_tt = table.symbol_tt[symbol]
  nb_bits_out = (s_tt.delta_nb_bits + (1 << 15)) >> 16
  value = (nb_bits_out << 16) - s_tt.delta_nb_bits
  idx = (value >> nb_bits_out) + s_tt.delta_find_state
  new(table.state_table[idx], table.table_log)
end

Instance Method Details

#encode(bitc, table, symbol) ⇒ Object 



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# File 'lib/omnizip/algorithms/zstandard/fse/encoder.rb', line 517

def encode(bitc, table, symbol)
  s_tt = table.symbol_tt[symbol]
  nb_bits_out = (@value + s_tt.delta_nb_bits) >> 16
  bitc.add_bits(@value, nb_bits_out)
  idx = (@value >> nb_bits_out) + s_tt.delta_find_state
  @value = table.state_table[idx]
end

#flush(bitc) ⇒ Object 



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# File 'lib/omnizip/algorithms/zstandard/fse/encoder.rb', line 525

def flush(bitc)
  bitc.add_bits(@value, @state_log)
  bitc.flush
end