diff options
Diffstat (limited to 'encoder.cc')
| -rw-r--r-- | encoder.cc | 106 |
1 files changed, 55 insertions, 51 deletions
@@ -38,8 +38,8 @@ #include "encoder.h" -const Dis_slots dis_slots; -const Prob_prices prob_prices; +const Dis_slots Lzlib_namespace::dis_slots; +const Prob_prices Lzlib_namespace::prob_prices; int Matchfinder::write_data( const uint8_t * const in_buffer, const int in_size ) throw() @@ -140,10 +140,11 @@ int Matchfinder::longest_match_len( int * const distances ) throw() const uint8_t * const data = buffer + pos; const int key2 = num_prev_positions4 + num_prev_positions3 + ( ( (int)data[0] << 8 ) | data[1] ); - const int tmp = crc32[data[0]] ^ data[1] ^ ( (int)data[2] << 8 ); - const int key3 = num_prev_positions4 + ( tmp & ( num_prev_positions3 - 1 ) ); - const int key4 = ( tmp ^ ( crc32[data[3]] << 5 ) ) & - ( num_prev_positions4 - 1 ); + const uint32_t tmp = crc32[data[0]] ^ data[1] ^ ( (uint32_t)data[2] << 8 ); + const int key3 = num_prev_positions4 + + (int)( tmp & ( num_prev_positions3 - 1 ) ); + const int key4 = (int)( ( tmp ^ ( crc32[data[3]] << 5 ) ) & + ( num_prev_positions4 - 1 ) ); if( distances ) { @@ -251,8 +252,8 @@ void LZ_encoder::fill_distance_prices() throw() { for( int dis_state = 0; dis_state < max_dis_states; ++dis_state ) { - int * dsp = dis_slot_prices[dis_state]; - const Bit_model * bmds = bm_dis_slot[dis_state]; + int * const dsp = dis_slot_prices[dis_state]; + const Bit_model * const bmds = bm_dis_slot[dis_state]; int slot = 0; for( ; slot < end_dis_model && slot < num_dis_slots; ++slot ) dsp[slot] = price_symbol( bmds, slot, dis_slot_bits ); @@ -260,7 +261,7 @@ void LZ_encoder::fill_distance_prices() throw() dsp[slot] = price_symbol( bmds, slot, dis_slot_bits ) + (((( slot >> 1 ) - 1 ) - dis_align_bits ) << price_shift ); - int * dp = dis_prices[dis_state]; + int * const dp = dis_prices[dis_state]; int dis = 0; for( ; dis < start_dis_model; ++dis ) dp[dis] = dsp[dis]; @@ -276,8 +277,10 @@ void LZ_encoder::fill_distance_prices() throw() } -// Return value: ( dis == -1 ) && ( len == 1 ) means literal -int LZ_encoder::best_pair_sequence( const int reps[num_rep_distances], +// Return value == number of bytes advanced (ahead). +// trials[0]..trials[retval-1] contain the steps to encode. +// ( trials[0].dis == -1 && trials[0].price == 1 ) means literal. +int LZ_encoder::sequence_optimizer( const int reps[num_rep_distances], const State & state ) { int main_len; @@ -312,15 +315,14 @@ int LZ_encoder::best_pair_sequence( const int reps[num_rep_distances], return main_len; } - trials[0].state = state; - for( int i = 0; i < num_rep_distances; ++i ) trials[0].reps[i] = reps[i]; - + { + const int pos_state = matchfinder.data_position() & pos_state_mask; const uint8_t prev_byte = matchfinder[-1]; const uint8_t cur_byte = matchfinder[0]; const uint8_t match_byte = matchfinder[-reps[0]-1]; - unsigned int position = matchfinder.data_position(); - const int pos_state = position & pos_state_mask; + trials[0].state = state; + for( int i = 0; i < num_rep_distances; ++i ) trials[0].reps[i] = reps[i]; trials[1].dis = -1; trials[1].prev_index = 0; trials[1].price = price0( bm_match[state()][pos_state] ); @@ -368,6 +370,7 @@ int LZ_encoder::best_pair_sequence( const int reps[num_rep_distances], trials[len].update( rep, 0, price + rep_match_len_encoder.price( len, pos_state ) ); } + } int cur = 0; int num_trials = main_len; @@ -375,7 +378,7 @@ int LZ_encoder::best_pair_sequence( const int reps[num_rep_distances], while( true ) { - if( ++cur >= num_trials ) + if( ++cur >= num_trials ) // no more initialized trials { backward( cur ); return cur; @@ -407,10 +410,11 @@ int LZ_encoder::best_pair_sequence( const int reps[num_rep_distances], mtf_reps( cur_trial.dis, cur_trial.reps ); } + const int pos_state = matchfinder.data_position() & pos_state_mask; const uint8_t prev_byte = matchfinder[-1]; const uint8_t cur_byte = matchfinder[0]; const uint8_t match_byte = matchfinder[-cur_trial.reps[0]-1]; - const int pos_state = ++position & pos_state_mask; + int next_price = cur_trial.price + price0( bm_match[cur_trial.state()][pos_state] ); if( cur_trial.state.is_char() ) next_price += literal_encoder.price_symbol( prev_byte, cur_byte ); @@ -454,7 +458,7 @@ int LZ_encoder::best_pair_sequence( const int reps[num_rep_distances], if( newlen <= len_limit && ( newlen > min_match_len || ( newlen == min_match_len && - match_distances[newlen] < modeled_distances ) ) ) + match_distances[min_match_len] < modeled_distances ) ) ) { const int normal_match_price = match_price + price0( bm_rep[cur_trial.state()] ); @@ -470,37 +474,38 @@ int LZ_encoder::best_pair_sequence( const int reps[num_rep_distances], } - // Sync Flush mark => (dis == 0xFFFFFFFF, len == min_match_len + 1) -bool LZ_encoder::sync_flush() + // End Of Stream mark => (dis == 0xFFFFFFFFU, len == min_match_len) +bool LZ_encoder::full_flush( const State & state ) { - if( member_finished_ || range_encoder.free_bytes() < max_marker_size ) + if( member_finished_ || + range_encoder.free_bytes() < File_trailer::size() + max_marker_size ) return false; - const int pos_state = ( matchfinder.data_position() ) & pos_state_mask; + const int pos_state = matchfinder.data_position() & pos_state_mask; range_encoder.encode_bit( bm_match[state()][pos_state], 1 ); range_encoder.encode_bit( bm_rep[state()], 0 ); - encode_pair( 0xFFFFFFFF, min_match_len + 1, pos_state ); + encode_pair( 0xFFFFFFFFU, min_match_len, pos_state ); range_encoder.flush(); + File_trailer trailer; + trailer.data_crc( crc() ); + trailer.data_size( matchfinder.data_position() ); + trailer.member_size( range_encoder.member_position() + File_trailer::size() ); + for( int i = 0; i < File_trailer::size(); ++i ) + range_encoder.put_byte( trailer.data[i] ); return true; } - // End Of Stream mark => (dis == 0xFFFFFFFF, len == min_match_len) -bool LZ_encoder::full_flush() + // Sync Flush mark => (dis == 0xFFFFFFFFU, len == min_match_len + 1) +bool LZ_encoder::sync_flush() { - if( member_finished_ || - range_encoder.free_bytes() < (int)sizeof (File_trailer) + max_marker_size ) + if( member_finished_ || range_encoder.free_bytes() < max_marker_size ) return false; - const int pos_state = ( matchfinder.data_position() ) & pos_state_mask; + const State & state = main_state; + const int pos_state = matchfinder.data_position() & pos_state_mask; range_encoder.encode_bit( bm_match[state()][pos_state], 1 ); range_encoder.encode_bit( bm_rep[state()], 0 ); - encode_pair( 0xFFFFFFFF, min_match_len, pos_state ); + encode_pair( 0xFFFFFFFFU, min_match_len + 1, pos_state ); range_encoder.flush(); - File_trailer trailer; - trailer.data_crc( crc() ); - trailer.data_size( matchfinder.data_position() ); - trailer.member_size( range_encoder.member_position() + sizeof trailer ); - for( unsigned int i = 0; i < sizeof trailer; ++i ) - range_encoder.put_byte( ((uint8_t *)&trailer)[i] ); return true; } @@ -508,14 +513,12 @@ bool LZ_encoder::full_flush() LZ_encoder::LZ_encoder( Matchfinder & mf, const File_header & header, const long long member_size ) : - member_size_limit( member_size - sizeof (File_trailer) - max_marker_size ), + member_size_limit( member_size - File_trailer::size() - max_marker_size ), longest_match_found( 0 ), - crc_( 0xFFFFFFFF ), + crc_( 0xFFFFFFFFU ), matchfinder( mf ), - range_encoder(), len_encoder( matchfinder.match_len_limit() ), rep_match_len_encoder( matchfinder.match_len_limit() ), - literal_encoder(), num_dis_slots( 2 * File_header::real_bits( matchfinder.dictionary_size() - 1 ) ), fill_counter( 0 ), member_finished_( false ) @@ -523,16 +526,17 @@ LZ_encoder::LZ_encoder( Matchfinder & mf, const File_header & header, for( int i = 0; i < num_rep_distances; ++i ) rep_distances[i] = 0; fill_align_prices(); - for( unsigned int i = 0; i < sizeof header; ++i ) - range_encoder.put_byte( ((uint8_t *)&header)[i] ); + for( int i = 0; i < File_header::size; ++i ) + range_encoder.put_byte( header.data[i] ); } bool LZ_encoder::encode_member( const bool finish ) { + State & state = main_state; if( member_finished_ ) return true; if( range_encoder.member_position() >= member_size_limit ) - { if( full_flush() ) { member_finished_ = true; } return true; } + { if( full_flush( state ) ) { member_finished_ = true; } return true; } // encode first byte if( matchfinder.data_position() == 0 && !matchfinder.finished() ) @@ -551,29 +555,30 @@ bool LZ_encoder::encode_member( const bool finish ) { if( matchfinder.finished() ) { - if( finish && full_flush() ) member_finished_ = true; + if( finish && full_flush( state ) ) member_finished_ = true; return true; } if( !matchfinder.enough_available_bytes() || !range_encoder.enough_free_bytes() ) return true; if( fill_counter <= 0 ) { fill_distance_prices(); fill_counter = 512; } - int ahead = best_pair_sequence( rep_distances, state ); + int ahead = sequence_optimizer( rep_distances, state ); if( ahead <= 0 ) return false; fill_counter -= ahead; for( int i = 0; ; ) { const int pos_state = ( matchfinder.data_position() - ahead ) & pos_state_mask; - int dis = trials[i].dis; + const int dis = trials[i].dis; const int len = trials[i].price; bool bit = ( dis < 0 && len == 1 ); range_encoder.encode_bit( bm_match[state()][pos_state], !bit ); - if( bit ) + if( bit ) // literal byte { const uint8_t prev_byte = matchfinder[-ahead-1]; const uint8_t cur_byte = matchfinder[-ahead]; + crc32.update( crc_, cur_byte ); if( state.is_char() ) literal_encoder.encode( range_encoder, prev_byte, cur_byte ); else @@ -583,8 +588,9 @@ bool LZ_encoder::encode_member( const bool finish ) } state.set_char(); } - else + else // match or repeated match { + crc32.update( crc_, matchfinder.ptr_to_current_pos() - ahead, len ); mtf_reps( dis, rep_distances ); bit = ( dis < num_rep_distances ); range_encoder.encode_bit( bm_rep[state()], bit ); @@ -613,13 +619,11 @@ bool LZ_encoder::encode_member( const bool finish ) state.set_match(); } } - for( int j = 0; j < len; ++j ) - crc32.update( crc_, matchfinder[j-ahead] ); ahead -= len; i += len; if( range_encoder.member_position() >= member_size_limit ) { if( !matchfinder.dec_pos( ahead ) ) return false; - if( full_flush() ) member_finished_ = true; + if( full_flush( state ) ) member_finished_ = true; return true; } if( ahead <= 0 ) break; |