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author | Daniel Baumann <mail@daniel-baumann.ch> | 2015-11-07 13:45:54 +0000 |
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committer | Daniel Baumann <mail@daniel-baumann.ch> | 2015-11-07 13:45:54 +0000 |
commit | 53eee7f4e2ef4d4211df3e860e3c787fbd83c3e8 (patch) | |
tree | cff02b70b5a48f7cefa4a5ad4c4ab745e2b64dd6 /encoder.h | |
parent | Adding upstream version 1.2. (diff) | |
download | lzlib-53eee7f4e2ef4d4211df3e860e3c787fbd83c3e8.tar.xz lzlib-53eee7f4e2ef4d4211df3e860e3c787fbd83c3e8.zip |
Adding upstream version 1.3.upstream/1.3
Signed-off-by: Daniel Baumann <mail@daniel-baumann.ch>
Diffstat (limited to 'encoder.h')
-rw-r--r-- | encoder.h | 620 |
1 files changed, 0 insertions, 620 deletions
diff --git a/encoder.h b/encoder.h deleted file mode 100644 index 6d9036d..0000000 --- a/encoder.h +++ /dev/null @@ -1,620 +0,0 @@ -/* Lzlib - A compression library for lzip files - Copyright (C) 2009, 2010, 2011 Antonio Diaz Diaz. - - This library is free software: you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation, either version 3 of the License, or - (at your option) any later version. - - This library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - GNU General Public License for more details. - - You should have received a copy of the GNU General Public License - along with this library. If not, see <http://www.gnu.org/licenses/>. - - As a special exception, you may use this file as part of a free - software library without restriction. Specifically, if other files - instantiate templates or use macros or inline functions from this - file, or you compile this file and link it with other files to - produce an executable, this file does not by itself cause the - resulting executable to be covered by the GNU General Public - License. This exception does not however invalidate any other - reasons why the executable file might be covered by the GNU General - Public License. -*/ - -namespace Lzlib { - -enum { max_num_trials = 1 << 12, - price_shift = 6 }; - -class Dis_slots - { - unsigned char data[1<<12]; - -public: - Dis_slots() - { - for( int slot = 0; slot < 4; ++slot ) data[slot] = slot; - for( int i = 4, size = 2, slot = 4; slot < 24; slot += 2 ) - { - std::memset( &data[i], slot, size ); - std::memset( &data[i+size], slot + 1, size ); - size <<= 1; - i += size; - } - } - - unsigned char table( const int dis ) const throw() { return data[dis]; } - - int operator[]( const uint32_t dis ) const throw() - { - if( dis < (1 << 12) ) return data[dis]; - if( dis < (1 << 23) ) return data[dis>>11] + 22; - return data[dis>>22] + 44; - } - }; - -extern const Dis_slots dis_slots; - - -class Prob_prices - { - int data[bit_model_total >> 2]; - -public: - Prob_prices() - { - const int num_bits = ( bit_model_total_bits - 2 ); - int j = 1, end = 2; - data[0] = bit_model_total_bits << price_shift; - for( int i = num_bits - 1; i >= 0; --i, end <<= 1 ) - { - for( ; j < end; ++j ) - data[j] = ( i << price_shift ) + - ( ( (end - j) << price_shift ) >> ( num_bits - i - 1 ) ); - } - } - - int operator[]( const int probability ) const throw() - { return data[probability >> 2]; } - }; - -extern const Prob_prices prob_prices; - - -inline int price0( const Bit_model & bm ) throw() - { return prob_prices[bm.probability]; } - -inline int price1( const Bit_model & bm ) throw() - { return prob_prices[bit_model_total-bm.probability]; } - -inline int price_bit( const Bit_model & bm, const int bit ) throw() - { if( bit ) return price1( bm ); else return price0( bm ); } - - -inline int price_symbol( const Bit_model bm[], int symbol, const int num_bits ) throw() - { - int price = 0; - symbol |= ( 1 << num_bits ); - while( symbol > 1 ) - { - const int bit = symbol & 1; - symbol >>= 1; - price += price_bit( bm[symbol], bit ); - } - return price; - } - - -inline int price_symbol_reversed( const Bit_model bm[], int symbol, - const int num_bits ) throw() - { - int price = 0; - int model = 1; - for( int i = num_bits; i > 0; --i ) - { - const int bit = symbol & 1; - symbol >>= 1; - price += price_bit( bm[model], bit ); - model = ( model << 1 ) | bit; - } - return price; - } - - -inline int price_matched( const Bit_model bm[], const int symbol, - const int match_byte ) throw() - { - int price = 0; - int model = 1; - - for( int i = 7; i >= 0; --i ) - { - const int match_bit = ( match_byte >> i ) & 1; - int bit = ( symbol >> i ) & 1; - price += price_bit( bm[(match_bit<<8)+model+0x100], bit ); - model = ( model << 1 ) | bit; - if( match_bit != bit ) - { - while( --i >= 0 ) - { - bit = ( symbol >> i ) & 1; - price += price_bit( bm[model], bit ); - model = ( model << 1 ) | bit; - } - break; - } - } - return price; - } - - -class Matchfinder - { - enum { // bytes to keep in buffer before dictionary - before_size = max_num_trials + 1, - // bytes to keep in buffer after pos - after_size = max_num_trials + max_match_len, - num_prev_positions4 = 1 << 20, - num_prev_positions3 = 1 << 18, - num_prev_positions2 = 1 << 16, - num_prev_positions = num_prev_positions4 + num_prev_positions3 + - num_prev_positions2 }; - - long long partial_data_pos; - const int dictionary_size_; // bytes to keep in buffer before pos - const int buffer_size; - uint8_t * const buffer; // input buffer - int32_t * const prev_positions; // last seen position of key - int32_t * const prev_pos_tree; - int pos; // current pos in buffer - int cyclic_pos; // current pos in dictionary - int stream_pos; // first byte not yet read from file - const int pos_limit; // when reached, a new block must be read - const int match_len_limit_; - const int cycles; - bool at_stream_end_; // stream_pos shows real end of file - bool been_flushed; - -public: - Matchfinder( const int dict_size, const int len_limit ); - - ~Matchfinder() - { delete[] prev_pos_tree; delete[] prev_positions; delete[] buffer; } - - uint8_t operator[]( const int i ) const throw() { return buffer[pos+i]; } - bool at_stream_end() const throw() { return at_stream_end_; } - int available_bytes() const throw() { return stream_pos - pos; } - long long data_position() const throw() { return partial_data_pos + pos; } - int dictionary_size() const throw() { return dictionary_size_; } - bool finished() const throw() { return at_stream_end_ && pos >= stream_pos; } - void flushing( const bool b ) throw() { at_stream_end_ = b; } - int free_bytes() const throw() - { if( at_stream_end_ ) return 0; return buffer_size - stream_pos; } - int match_len_limit() const throw() { return match_len_limit_; } - const uint8_t * ptr_to_current_pos() const throw() { return buffer + pos; } - - bool dec_pos( const int ahead ) throw() - { - if( ahead < 0 || pos < ahead ) return false; - pos -= ahead; - cyclic_pos -= ahead; - if( cyclic_pos < 0 ) cyclic_pos += dictionary_size_; - return true; - } - - bool enough_available_bytes() const throw() - { - return ( stream_pos > pos && - ( at_stream_end_ || stream_pos - pos >= after_size ) ); - } - - int true_match_len( const int index, const int distance, int len_limit ) const throw() - { - if( index + len_limit > available_bytes() ) - len_limit = available_bytes() - index; - const uint8_t * const data = buffer + pos + index - distance; - int i = 0; - while( i < len_limit && data[i] == data[i+distance] ) ++i; - return i; - } - - int write_data( const uint8_t * const in_buffer, const int in_size ) throw(); - void reset() throw(); - bool move_pos() throw(); - int longest_match_len( int * const distances = 0 ) throw(); - }; - - -class Range_encoder : public Circular_buffer - { - enum { min_free_bytes = 2 * max_num_trials }; - uint64_t low; - long long partial_member_pos; - uint32_t range; - int ff_count; - uint8_t cache; - - void shift_low() - { - const uint32_t carry = low >> 32; - if( low < 0xFF000000U || carry == 1 ) - { - put_byte( cache + carry ); - for( ; ff_count > 0; --ff_count ) put_byte( 0xFF + carry ); - cache = low >> 24; - } - else ++ff_count; - low = ( low & 0x00FFFFFFU ) << 8; - } - -public: - Range_encoder() - : - Circular_buffer( 65536 + min_free_bytes ), - low( 0 ), - partial_member_pos( 0 ), - range( 0xFFFFFFFFU ), - ff_count( 0 ), - cache( 0 ) {} - - long long member_position() const throw() - { return partial_member_pos + used_bytes() + ff_count; } - - bool enough_free_bytes() const throw() - { return free_bytes() >= min_free_bytes; } - - int read_data( uint8_t * const out_buffer, const int out_size ) throw() - { - const int size = Circular_buffer::read_data( out_buffer, out_size ); - if( size > 0 ) partial_member_pos += size; - return size; - } - - void flush() - { - for( int i = 0; i < 5; ++i ) shift_low(); - low = 0; - range = 0xFFFFFFFFU; - ff_count = 0; - cache = 0; - } - - void encode( const int symbol, const int num_bits ) - { - for( int i = num_bits - 1; i >= 0; --i ) - { - range >>= 1; - if( (symbol >> i) & 1 ) low += range; - if( range <= 0x00FFFFFFU ) { range <<= 8; shift_low(); } - } - } - - void encode_bit( Bit_model & bm, const int bit ) - { - const uint32_t bound = ( range >> bit_model_total_bits ) * bm.probability; - if( !bit ) - { - range = bound; - bm.probability += (bit_model_total - bm.probability) >> bit_model_move_bits; - } - else - { - low += bound; - range -= bound; - bm.probability -= bm.probability >> bit_model_move_bits; - } - if( range <= 0x00FFFFFFU ) { range <<= 8; shift_low(); } - } - - void encode_tree( Bit_model bm[], const int symbol, const int num_bits ) - { - int mask = ( 1 << ( num_bits - 1 ) ); - int model = 1; - for( int i = num_bits; i > 0; --i, mask >>= 1 ) - { - const int bit = ( symbol & mask ); - encode_bit( bm[model], bit ); - model <<= 1; - if( bit ) model |= 1; - } - } - - void encode_tree_reversed( Bit_model bm[], int symbol, const int num_bits ) - { - int model = 1; - for( int i = num_bits; i > 0; --i ) - { - const int bit = symbol & 1; - encode_bit( bm[model], bit ); - model = ( model << 1 ) | bit; - symbol >>= 1; - } - } - - void encode_matched( Bit_model bm[], int symbol, int match_byte ) - { - int model = 1; - for( int i = 7; i >= 0; --i ) - { - const int match_bit = ( match_byte >> i ) & 1; - int bit = ( symbol >> i ) & 1; - encode_bit( bm[(match_bit<<8)+model+0x100], bit ); - model = ( model << 1 ) | bit; - if( match_bit != bit ) - { - while( --i >= 0 ) - { - bit = ( symbol >> i ) & 1; - encode_bit( bm[model], bit ); - model = ( model << 1 ) | bit; - } - break; - } - } - } - }; - - -class Len_encoder - { - 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]; - int prices[pos_states][max_len_symbols]; - const int len_symbols; - int counters[pos_states]; - - void update_prices( const int pos_state ) throw() - { - int * const pps = prices[pos_state]; - int tmp = price0( choice1 ); - int len = 0; - for( ; len < len_low_symbols && len < len_symbols; ++len ) - pps[len] = tmp + - price_symbol( bm_low[pos_state], len, len_low_bits ); - tmp = price1( choice1 ); - for( ; len < len_low_symbols + len_mid_symbols && len < len_symbols; ++len ) - pps[len] = tmp + price0( choice2 ) + - price_symbol( bm_mid[pos_state], len - len_low_symbols, len_mid_bits ); - for( ; len < len_symbols; ++len ) - // using 4 slots per value makes "price" faster - prices[3][len] = prices[2][len] = prices[1][len] = prices[0][len] = - tmp + price1( choice2 ) + - price_symbol( bm_high, len - len_low_symbols - len_mid_symbols, len_high_bits ); - counters[pos_state] = len_symbols; - } - -public: - Len_encoder( const int len_limit ) - : len_symbols( len_limit + 1 - min_match_len ) - { - for( int i = 0; i < pos_states; ++i ) update_prices( i ); - } - - void encode( Range_encoder & range_encoder, int symbol, - const int pos_state ); - - int price( const int symbol, const int pos_state ) const throw() - { return prices[pos_state][symbol - min_match_len]; } - }; - - -class Literal_encoder - { - Bit_model bm_literal[1<<literal_context_bits][0x300]; - - int lstate( const uint8_t prev_byte ) const throw() - { return ( prev_byte >> ( 8 - literal_context_bits ) ); } - -public: - void encode( Range_encoder & range_encoder, - uint8_t prev_byte, uint8_t symbol ) - { range_encoder.encode_tree( bm_literal[lstate(prev_byte)], symbol, 8 ); } - - void encode_matched( Range_encoder & range_encoder, - uint8_t prev_byte, uint8_t symbol, uint8_t match_byte ) - { range_encoder.encode_matched( bm_literal[lstate(prev_byte)], - symbol, match_byte ); } - - int price_symbol( uint8_t prev_byte, uint8_t symbol ) const throw() - { return Lzlib::price_symbol( bm_literal[lstate(prev_byte)], symbol, 8 ); } - - int price_matched( uint8_t prev_byte, uint8_t symbol, - uint8_t match_byte ) const throw() - { return Lzlib::price_matched( bm_literal[lstate(prev_byte)], - symbol, match_byte ); } - }; - - -class LZ_encoder - { - enum { infinite_price = 0x0FFFFFFF, - max_marker_size = 16, - num_rep_distances = 4 }; // must be 4 - - struct Trial - { - State state; - int dis; - int prev_index; // index of prev trial in trials[] - int price; // dual use var; cumulative price, match length - int reps[num_rep_distances]; - void update( const int d, const int p_i, const int pr ) throw() - { if( pr < price ) { dis = d; prev_index = p_i; price = pr; } } - }; - - const long long member_size_limit; - int longest_match_found; - uint32_t crc_; - - Bit_model bm_match[State::states][pos_states]; - Bit_model bm_rep[State::states]; - Bit_model bm_rep0[State::states]; - Bit_model bm_rep1[State::states]; - Bit_model bm_rep2[State::states]; - Bit_model bm_len[State::states][pos_states]; - Bit_model bm_dis_slot[max_dis_states][1<<dis_slot_bits]; - Bit_model bm_dis[modeled_distances-end_dis_model+1]; - Bit_model bm_align[dis_align_size]; - - Matchfinder & matchfinder; - Range_encoder range_encoder; - Len_encoder len_encoder; - Len_encoder rep_match_len_encoder; - Literal_encoder literal_encoder; - - const int num_dis_slots; - int rep_distances[num_rep_distances]; - int match_distances[max_match_len+1]; - Trial trials[max_num_trials]; - - int dis_slot_prices[max_dis_states][2*max_dictionary_bits]; - int dis_prices[max_dis_states][modeled_distances]; - int align_prices[dis_align_size]; - int align_price_count; - int fill_counter; - State main_state; - bool member_finished_; - - void fill_align_prices() throw(); - void fill_distance_prices() throw(); - - uint32_t crc() const throw() { return crc_ ^ 0xFFFFFFFFU; } - - // move-to-front dis in/into reps - void mtf_reps( const int dis, int reps[num_rep_distances] ) throw() - { - if( dis >= num_rep_distances ) - { - for( int i = num_rep_distances - 1; i > 0; --i ) reps[i] = reps[i-1]; - reps[0] = dis - num_rep_distances; - } - else if( dis > 0 ) - { - const int distance = reps[dis]; - for( int i = dis; i > 0; --i ) reps[i] = reps[i-1]; - reps[0] = distance; - } - } - - int price_rep_len1( const State & state, const int pos_state ) const throw() - { - return price0( bm_rep0[state()] ) + price0( bm_len[state()][pos_state] ); - } - - int price_rep( const int rep, const State & state, - const int pos_state ) const throw() - { - if( rep == 0 ) return price0( bm_rep0[state()] ) + - price1( bm_len[state()][pos_state] ); - int price = price1( bm_rep0[state()] ); - if( rep == 1 ) - price += price0( bm_rep1[state()] ); - else - { - price += price1( bm_rep1[state()] ); - price += price_bit( bm_rep2[state()], rep - 2 ); - } - return price; - } - - int price_dis( const int dis, const int dis_state ) const throw() - { - if( dis < modeled_distances ) - return dis_prices[dis_state][dis]; - else - return dis_slot_prices[dis_state][dis_slots[dis]] + - align_prices[dis & (dis_align_size - 1)]; - } - - int price_pair( const int dis, const int len, const int pos_state ) const throw() - { - if( len <= min_match_len && dis >= modeled_distances ) - return infinite_price; - return len_encoder.price( len, pos_state ) + - price_dis( dis, get_dis_state( len ) ); - } - - void encode_pair( const uint32_t dis, const int len, const int pos_state ) throw() - { - len_encoder.encode( range_encoder, len, pos_state ); - const int dis_slot = dis_slots[dis]; - range_encoder.encode_tree( bm_dis_slot[get_dis_state(len)], dis_slot, dis_slot_bits ); - - if( dis_slot >= start_dis_model ) - { - const int direct_bits = ( dis_slot >> 1 ) - 1; - const uint32_t base = ( 2 | ( dis_slot & 1 ) ) << direct_bits; - const uint32_t direct_dis = dis - base; - - if( dis_slot < end_dis_model ) - range_encoder.encode_tree_reversed( bm_dis + base - dis_slot, - direct_dis, direct_bits ); - else - { - range_encoder.encode( direct_dis >> dis_align_bits, direct_bits - dis_align_bits ); - range_encoder.encode_tree_reversed( bm_align, direct_dis, dis_align_bits ); - if( --align_price_count <= 0 ) fill_align_prices(); - } - } - } - - int read_match_distances() throw() - { - int len = matchfinder.longest_match_len( match_distances ); - if( len == matchfinder.match_len_limit() ) - len += matchfinder.true_match_len( len, match_distances[len] + 1, max_match_len - len ); - return len; - } - - bool move_pos( int n, bool skip = false ) throw() - { - while( --n >= 0 ) - { - if( skip ) skip = false; - else matchfinder.longest_match_len(); - if( !matchfinder.move_pos() ) return false; - } - return true; - } - - void backward( int cur ) - { - int & dis = trials[cur].dis; - while( cur > 0 ) - { - const int prev_index = trials[cur].prev_index; - Trial & prev_trial = trials[prev_index]; - prev_trial.price = cur - prev_index; // len - cur = dis; dis = prev_trial.dis; prev_trial.dis = cur; - cur = prev_index; - } - } - - int sequence_optimizer( const int reps[num_rep_distances], - const State & state ); - - bool full_flush( const State & state ); - -public: - LZ_encoder( Matchfinder & mf, const File_header & header, - const long long member_size ); - - bool encode_member( const bool finish ); - bool member_finished() const throw() - { return member_finished_ && !range_encoder.used_bytes(); } - int read_data( uint8_t * const buffer, const int size ) throw() - { return range_encoder.read_data( buffer, size ); } - bool sync_flush(); - - long long member_position() const throw() - { return range_encoder.member_position(); } - }; - -} // end namespace Lzlib |