diff options
Diffstat (limited to 'decoder.h')
| -rw-r--r-- | decoder.h | 51 |
1 files changed, 20 insertions, 31 deletions
@@ -122,22 +122,22 @@ public: int decode_tree( Bit_model bm[], const int num_bits ) { - int model = 1; + int symbol = 1; for( int i = num_bits; i > 0; --i ) - model = ( model << 1 ) | decode_bit( bm[model] ); - return model - (1 << num_bits); + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + return symbol - (1 << num_bits); } int decode_tree6( Bit_model bm[] ) { - int model = 1; - model = ( model << 1 ) | decode_bit( bm[model] ); - model = ( model << 1 ) | decode_bit( bm[model] ); - model = ( model << 1 ) | decode_bit( bm[model] ); - model = ( model << 1 ) | decode_bit( bm[model] ); - model = ( model << 1 ) | decode_bit( bm[model] ); - model = ( model << 1 ) | decode_bit( bm[model] ); - return model - (1 << 6); + int symbol = 1; + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + symbol = ( symbol << 1 ) | decode_bit( bm[symbol] ); + return symbol - (1 << 6); } int decode_tree_reversed( Bit_model bm[], const int num_bits ) @@ -186,27 +186,16 @@ public: } return symbol - 0x100; } - }; - -class Len_decoder - { - Bit_model choice1; - Bit_model choice2; - Bit_model bm_low[pos_states][len_low_symbols]; - Bit_model bm_mid[pos_states][len_mid_symbols]; - Bit_model bm_high[len_high_symbols]; - -public: - int decode( Range_decoder & range_decoder, const int pos_state ) + int decode_len( Len_model & lm, const int pos_state ) { - if( range_decoder.decode_bit( choice1 ) == 0 ) - return range_decoder.decode_tree( bm_low[pos_state], len_low_bits ); - if( range_decoder.decode_bit( choice2 ) == 0 ) + if( decode_bit( lm.choice1 ) == 0 ) + return decode_tree( lm.bm_low[pos_state], len_low_bits ); + if( decode_bit( lm.choice2 ) == 0 ) return len_low_symbols + - range_decoder.decode_tree( bm_mid[pos_state], len_mid_bits ); + decode_tree( lm.bm_mid[pos_state], len_mid_bits ); return len_low_symbols + len_mid_symbols + - range_decoder.decode_tree( bm_high, len_high_bits ); + decode_tree( lm.bm_high, len_high_bits ); } }; @@ -216,7 +205,7 @@ class LZ_decoder const unsigned long long outskip; const unsigned long long outend; unsigned long long partial_data_pos; - Range_decoder & range_decoder; + Range_decoder & rdec; const int dictionary_size; const int buffer_size; uint8_t * const buffer; // output buffer @@ -270,14 +259,14 @@ class LZ_decoder void operator=( const LZ_decoder & ); // declared as private public: - LZ_decoder( const File_header & header, Range_decoder & rdec, const int ofd, + LZ_decoder( const File_header & header, Range_decoder & rde, const int ofd, const unsigned long long oskip = 0, const unsigned long long oend = -1ULL ) : outskip( oskip ), outend( oend ), partial_data_pos( 0 ), - range_decoder( rdec ), + rdec( rde ), dictionary_size( header.dictionary_size() ), buffer_size( std::max( 65536, dictionary_size ) ), buffer( new uint8_t[buffer_size] ), |