paq-master/0000755000175000017500000000000013134607302011221 5ustar jdgjdgpaq-master/README.md0000644000175000017500000000024513134607302012501 0ustar jdgjdg# PAQ: Python bingding for paq9a ## Install ```bash pip install paq ``` ## Usage ```python import paq assert b'1234' == paq.decompress(paq.compress(b'1234')) ```paq-master/setup.py0000644000175000017500000000163713134607302012742 0ustar jdgjdgfrom setuptools import Extension, setup from Cython.Build import cythonize paq_ext = Extension( name="paq._paq", sources=["paq/_paq.pyx"], include_dirs=['paq'], extra_compile_args=['-O3'], language='c++', ) setup(name='paq', version='0.1.1', description='Python binding for paq9a', author='Jingchao Hu', author_email='jingchaohu@gmail.com', url='http://github.com/observerss/paq', packages=['paq'], package_data={'paq': ['*.pyx', '*.h']}, include_package_data=True, install_requires=['cython'], python_requires='>=3.5', ext_modules=cythonize([paq_ext]), classifiers=[ 'Development Status :: 4 - Beta', 'Intended Audience :: Developers', 'Topic :: System :: Archiving :: Compression', 'License :: OSI Approved :: MIT License', 'Programming Language :: Python :: 3', ] ) paq-master/paq/0000755000175000017500000000000013134607302012002 5ustar jdgjdgpaq-master/paq/paq9a.h0000644000175000017500000010557113134607302013177 0ustar jdgjdg/* paq9a archiver, Dec. 31, 2007 (C) 2007, Matt Mahoney LICENSE This program 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 program 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 at Visit . paq9a is an experimental file compressor and archiver. Usage: paq9a {a|x|l} archive [[-opt] files...]... Commands: a = create archive and compress named files. x = extract from archive. l = list contents. Archives are "solid". You can only create new archives. You cannot modify existing archives. File names are stored and extracted exactly as named when the archive is created, but you have the option to rename them during extraction. Files are never clobbered. The "a" command creates a new archive and adds the named files. Wildcards are permitted if compiled with g++. Options and filenames may be in any order. Options apply only to filenames after the option, and override previous options. Options are: -s = store without compression. -c = compress (default). -1 through -9 selects memory level from 18 MB to 1.5 GB Default is -7 using 405 MB. The memory option must be set before the first file. Decompression requires the same amount of memory. For example: paq9a a foo.paq9a a.txt -3 -s b.txt -c c.txt tmp/d.txt /tmp/e.txt creates the archive foo.paq9a with 5 files. The file b.txt is stored without compression. The other 4 files are compressed at memory level 3. Extraction requires the same memory as compression. If any named file does not exist, then it is omitted from the archive with a warning and the remaining files are added. An existing archive cannot be overwritten. There must be at least one filename on the command line. The "x" command extracts the archive contents, creating files exactly as named when the archive was created. Files cannot be overwritten. If a file already exists or cannot be created, then it is skipped. For example, "tmp/d.txt" would be skipped if either the current directory does not have a subdirectory tmp, or tmp is write protected, or tmp/d.txt already exists. If "x" is followed by one or more file names, then the output files are renamed in the order they were added to the archive and any remaining contents are extracted without renaming. For example: paq9a x foo.paq9a x.txt y.txt would extract a.txt to x.txt and b.txt to y.txt, then extract c.txt, tmp/d.txt and /tmp/e.txt. If the command line has more filenames than the archive then the extra arguments are ignored. Options are not allowed. The "l" (letter l) command lists the contents. Any extra arguments are ignored. Any other command, or no command, displays a help message. ARCHIVE FORMAT "lPq" 1 mem [filename {'\0' mode usize csize contents}...]... The first 4 bytes are "lPq\x01" (1 is the version number). mem is a digit '1' through '9', where '9' uses the most memory (1.5 GB). A file is stored as one or more blocks. The filename is stored only in the first block as a NUL terminated string. Subsequent blocks start with a 0. The mode is 's' if the block is stored and 'c' if compressed. usize = uncompressed size as a 4 byte big-endian number (MSB first). csize = compressed size as a 4 byte big-endian number. The contents is copied from the file itself if mode is 's' or the compressed contents otherwise. Its length is exactly csize bytes. COMPRESSED FORMAT Files are preprocessed with LZP and then compressed with a context mixing compressor and arithmetic coded one bit at a time. Model contents are maintained across files. The LZP stage predicts the next byte by matching the current context (order 12 or higher) to a rotating buffer. If a match is found then the next byte after the match is predicted. If the next byte matches the prediction, then a 1 bit is coded and the context is extended. Otherwise a 0 is coded followed by 8 bits of the actual byte in MSB to LSB order. A 1 bit is modeled using the match length as context, then refined in 3 stages using sucessively longer contexts. The predictions are adjusted by 2 input neurons selected by a context hash with the second input fixed. If the LZP prediction is missed, then the literal is coded using a chain of predicions which are mixed using neurons, where one input is the previous prediction and the second input is the prediction given the current context. The current context is mapped to an 8 bit state representing the bit history, the sequence of bits previously observed in that context. The bit history is used both to select the neuron and is mapped to a prediction that provides the second input. In addition, if the known bits of the current byte match the LZP incorrectly predicted byte, then this fact is used to select one of 2 sets of neurons (512 total). The contexts, in order, are sparse order-1 with gaps of 3, 2, and 1 byte, then orders 1 through 6, then word orders 0 and 1, where a word is a sequenece of case insensitive letters (useful for compressing text). Contexts longer than 1 are hashed. Order-n contexts consist of a hash of the last n bytes plus the 0 to 7 known bits of the current byte. The order 6 context and the word order 0 and 1 contexts also include the LZP predicted byte. All mixing is in the logistic or "stretched" domain: stretch(p) = ln(p/(1-p)), then "squashed" by the inverse function: squash(p) = 1/(1 + exp(-p)) before arithmetic coding. A 2 input neuron has 2 weights (w0 and w1) selected by context. Given inputs x0 and x1 (2 predictions, or one prediction and a constant), the output prediction is computed: p = w0*x0 + w1*x1. If the actual bit is y, then the weights are updated to minimize its coding cost: error = y - squash(p) w0 += x0 * error * L w1 += x1 * error * L where L is the learning rate, normally 1/256, but increased by a factor of 4 an 2 for the first 2 training cycles (using the 2 low bits of w0 as a counter). In the implementation, p is represented by a fixed point number with a 12 bit fractional part in the linear domain (0..4095) and 8 bits in the logistic domain (-2047..2047 representing -8..8). Weights are scaled by 24 bits. Both weights are initialized to 1/2, expecting 2 probabilities, weighted equally). However, when one input (x0) is fixed, its weight (w0) is initialized to 0. A bit history represents the sequence of 0 and 1 bits observed in a given context. An 8 bit state represents all possible sequences up to 4 bits long. Longer sequences are represented by a count of 0 and 1 bits, plus an indicator of the most recent bit. If counts grow too large, then the next state represents a pair of smaller counts with about the same ratio. The state table is the same as used in PAQ8 (all versions) and LPAQ1. A state is mapped to a prediction by using a table. A table entry contains 2 values, p, initialized to 1/2, and n, initialized to 0. The output prediciton is p (in the linear domain, not stretched). If the actual bit is y, then the entry is updated: error = y - p p += error/(n + 1.5) if n < limit then n += 1 In practice, p is scaled by 22 bits, and n is 10 bits, packed into one 32 bit integer. The limit is 255. Every 4 bits, contexts are mapped to arrays of 15 states using a hash table. The first element is the bit history for the current context ending on a half byte boundary, followed by all possible contexts formed by appending up to 3 more bits. A hash table accepts a 32 bit context, which must be a hash if longer than 4 bytes. The input is further hashed and divided into an index (depending on the table size, a power of 2), and an 8 bit checksum which is stored in the table and used to detect collisions (not perfectly). A lookup tests 3 adjacent locations within a single 64 byte cache line, and if a matching checksum is not found, then the entry with the smallest value in the first data element is replaced (LFU replacement policy). This element represents a bit history for a context ending on a half byte boundary. The states are ordered so that larger values represent larger total bit counts, which estimates the likelihood of future use. The initial state is 0. Memory is allocated from MEM = pow(2, opt+22) bytes, where opt is 1 through 9 (user selected). Of this, MEM/2 is for the hash table for storing literal context states, MEM/8 for the rotating LZP buffer, and MEM/8 for a hash table of pointers into the buffer, plus 12 MB for miscellaneous data. Total memory usage is 0.75*MEM + 12 MB. ARITHMETIC CODING The arithmetic coder codes a bit with probability p using log2(1/p) bits. Given input string y, the output is a binary fraction x such that P(< y) <= x < P(<= y) where P(< y) means the total probability of all inputs lexicographically less than y and P(<= y) = P(< y) + P(y). Note that one can always find x with length at most log2(P(y)) + 1 bits. x can be computed efficiently by maintaining a range, low <= x < high (initially 0..1) and expressing P(y) as a product of predictions: P(y) = P(y1) P(y2|y1) P(y3|y1y2) P(y4|y1y2y3) ... P(yn|y1y2...yn-1) where the term P(yi|y0y1...yi-1) means the probability that yi is 1 given the context y1...yi-1, the previous i-1 bits of y. For each prediction p, the range is split in proportion to the probabilities of 0 and 1, then updated by taking the half corresponding to the actual bit y as the new range, i.e. mid = low + (high - low) * p(y = 1) if y = 0 then (low, high) := (mid, high) if y = 1 then (low, high) := (low, mid) As low and high approach each other, the high order bits of x become known (because they are the same throughout the range) and can be output immediately. For decoding, the range is split as before and the range is updated to the half containing x. The corresponding bit y is used to update the model. Thus, the model has the same knowledge for coding and decoding. */ // #include // #include // #include // #include // #include #ifndef NDEBUG #define NDEBUG // remove for debugging #endif #include #include #include #include int allocated=0; // Total memory allocated by alloc() // Create an array p of n elements of type T template void alloc(T*&p, int n) { p=(T*)calloc(n, sizeof(T)); if (!p) printf("Out of memory\n"), exit(1); allocated+=n*sizeof(T); } // 8, 16, 32 bit unsigned types (adjust as appropriate) typedef unsigned char U8; typedef unsigned short U16; typedef unsigned int U32; ///////////////////////////// Squash ////////////////////////////// // return p = 1/(1 + exp(-d)), d scaled by 8 bits, p scaled by 12 bits class Squash { short tab[4096]; public: Squash(); int operator()(int d) { d+=2048; if (d<0) return 0; else if (d>4095) return 4095; else return tab[d]; } } squash; Squash::Squash() { static const int t[33]={ 1,2,3,6,10,16,27,45,73,120,194,310,488,747,1101, 1546,2047,2549,2994,3348,3607,3785,3901,3975,4022, 4050,4068,4079,4085,4089,4092,4093,4094}; for (int i=-2048; i<2048; ++i) { int w=i&127; int d=(i>>7)+16; tab[i+2048]=(t[d]*(128-w)+t[(d+1)]*w+64) >> 7; } } //////////////////////////// Stretch /////////////////////////////// // Inverse of squash. stretch(d) returns ln(p/(1-p)), d scaled by 8 bits, // p by 12 bits. d has range -2047 to 2047 representing -8 to 8. // p has range 0 to 4095 representing 0 to 1. class Stretch { short t[4096]; public: Stretch(); int operator()(int p) const { assert(p>=0 && p<4096); return t[p]; } } stretch; Stretch::Stretch() { int pi=0; for (int x=-2047; x<=2047; ++x) { // invert squash() int i=squash(x); for (int j=pi; j<=i; ++j) t[j]=x; pi=i+1; } t[4095]=2047; } ///////////////////////////// ilog ////////////////////////////// // ilog(x) = round(log2(x) * 16), 0 <= x < 64K class Ilog { U8 t[65536]; public: int operator()(U16 x) const {return t[x];} Ilog(); } ilog; // Compute lookup table by numerical integration of 1/x Ilog::Ilog() { U32 x=14155776; for (int i=2; i<65536; ++i) { x+=774541002/(i*2-1); // numerator is 2^29/ln 2 t[i]=x>>24; } } // llog(x) accepts 32 bits inline int llog(U32 x) { if (x>=0x1000000) return 256+ilog(x>>16); else if (x>=0x10000) return 128+ilog(x>>8); else return ilog(x); } ///////////////////////// state table //////////////////////// // State table: // nex(state, 0) = next state if bit y is 0, 0 <= state < 256 // nex(state, 1) = next state if bit y is 1 // // States represent a bit history within some context. // State 0 is the starting state (no bits seen). // States 1-30 represent all possible sequences of 1-4 bits. // States 31-252 represent a pair of counts, (n0,n1), the number // of 0 and 1 bits respectively. If n0+n1 < 16 then there are // two states for each pair, depending on if a 0 or 1 was the last // bit seen. // If n0 and n1 are too large, then there is no state to represent this // pair, so another state with about the same ratio of n0/n1 is substituted. // Also, when a bit is observed and the count of the opposite bit is large, // then part of this count is discarded to favor newer data over old. static const U8 State_table[256][2]={ { 1, 2},{ 3, 5},{ 4, 6},{ 7, 10},{ 8, 12},{ 9, 13},{ 11, 14}, // 0 { 15, 19},{ 16, 23},{ 17, 24},{ 18, 25},{ 20, 27},{ 21, 28},{ 22, 29}, // 7 { 26, 30},{ 31, 33},{ 32, 35},{ 32, 35},{ 32, 35},{ 32, 35},{ 34, 37}, // 14 { 34, 37},{ 34, 37},{ 34, 37},{ 34, 37},{ 34, 37},{ 36, 39},{ 36, 39}, // 21 { 36, 39},{ 36, 39},{ 38, 40},{ 41, 43},{ 42, 45},{ 42, 45},{ 44, 47}, // 28 { 44, 47},{ 46, 49},{ 46, 49},{ 48, 51},{ 48, 51},{ 50, 52},{ 53, 43}, // 35 { 54, 57},{ 54, 57},{ 56, 59},{ 56, 59},{ 58, 61},{ 58, 61},{ 60, 63}, // 42 { 60, 63},{ 62, 65},{ 62, 65},{ 50, 66},{ 67, 55},{ 68, 57},{ 68, 57}, // 49 { 70, 73},{ 70, 73},{ 72, 75},{ 72, 75},{ 74, 77},{ 74, 77},{ 76, 79}, // 56 { 76, 79},{ 62, 81},{ 62, 81},{ 64, 82},{ 83, 69},{ 84, 71},{ 84, 71}, // 63 { 86, 73},{ 86, 73},{ 44, 59},{ 44, 59},{ 58, 61},{ 58, 61},{ 60, 49}, // 70 { 60, 49},{ 76, 89},{ 76, 89},{ 78, 91},{ 78, 91},{ 80, 92},{ 93, 69}, // 77 { 94, 87},{ 94, 87},{ 96, 45},{ 96, 45},{ 48, 99},{ 48, 99},{ 88,101}, // 84 { 88,101},{ 80,102},{103, 69},{104, 87},{104, 87},{106, 57},{106, 57}, // 91 { 62,109},{ 62,109},{ 88,111},{ 88,111},{ 80,112},{113, 85},{114, 87}, // 98 {114, 87},{116, 57},{116, 57},{ 62,119},{ 62,119},{ 88,121},{ 88,121}, // 105 { 90,122},{123, 85},{124, 97},{124, 97},{126, 57},{126, 57},{ 62,129}, // 112 { 62,129},{ 98,131},{ 98,131},{ 90,132},{133, 85},{134, 97},{134, 97}, // 119 {136, 57},{136, 57},{ 62,139},{ 62,139},{ 98,141},{ 98,141},{ 90,142}, // 126 {143, 95},{144, 97},{144, 97},{ 68, 57},{ 68, 57},{ 62, 81},{ 62, 81}, // 133 { 98,147},{ 98,147},{100,148},{149, 95},{150,107},{150,107},{108,151}, // 140 {108,151},{100,152},{153, 95},{154,107},{108,155},{100,156},{157, 95}, // 147 {158,107},{108,159},{100,160},{161,105},{162,107},{108,163},{110,164}, // 154 {165,105},{166,117},{118,167},{110,168},{169,105},{170,117},{118,171}, // 161 {110,172},{173,105},{174,117},{118,175},{110,176},{177,105},{178,117}, // 168 {118,179},{110,180},{181,115},{182,117},{118,183},{120,184},{185,115}, // 175 {186,127},{128,187},{120,188},{189,115},{190,127},{128,191},{120,192}, // 182 {193,115},{194,127},{128,195},{120,196},{197,115},{198,127},{128,199}, // 189 {120,200},{201,115},{202,127},{128,203},{120,204},{205,115},{206,127}, // 196 {128,207},{120,208},{209,125},{210,127},{128,211},{130,212},{213,125}, // 203 {214,137},{138,215},{130,216},{217,125},{218,137},{138,219},{130,220}, // 210 {221,125},{222,137},{138,223},{130,224},{225,125},{226,137},{138,227}, // 217 {130,228},{229,125},{230,137},{138,231},{130,232},{233,125},{234,137}, // 224 {138,235},{130,236},{237,125},{238,137},{138,239},{130,240},{241,125}, // 231 {242,137},{138,243},{130,244},{245,135},{246,137},{138,247},{140,248}, // 238 {249,135},{250, 69},{ 80,251},{140,252},{249,135},{250, 69},{ 80,251}, // 245 {140,252},{ 0, 0},{ 0, 0},{ 0, 0}}; // 252 #define nex(state,sel) State_table[state][sel] //////////////////////////// StateMap ////////////////////////// // A StateMap maps a context to a probability. Methods: // // Statemap sm(n) creates a StateMap with n contexts using 4*n bytes memory. // sm.p(cx, limit) converts state cx (0..n-1) to a probability (0..4095) // that the next updated bit y=1. // limit (1..1023, default 255) is the maximum count for computing a // prediction. Larger values are better for stationary sources. // sm.update(y) updates the model with actual bit y (0..1). class StateMap { protected: const int N; // Number of contexts int cxt; // Context of last prediction U32 *t; // cxt -> prediction in high 22 bits, count in low 10 bits static int dt[1024]; // i -> 16K/(i+3) public: StateMap(int n=256); ~StateMap() { if (t) free(t); t = 0; } // update bit y (0..1) void update(int y, int limit=255) { assert(cxt>=0 && cxt>10; // count, prediction if (n>3)*dt[n]&0xfffffc00; } // predict next bit in context cx int p(int cx) { assert(cx>=0 && cx>20; } }; int StateMap::dt[1024]={0}; StateMap::StateMap(int n): N(n), cxt(0) { alloc(t, N); for (int i=0; i=0 && cx>16)+(x2=p2)*(wt[cxt+1]>>16)+128)>>8; } void update(int y) { assert(y==0 || y==1); int err=((y<<12)-squash(pr)); if ((wt[cxt]&3)<3) err*=4-(++wt[cxt]&3); err=(err+8)>>4; wt[cxt]+=x1*err&-4; wt[cxt+1]+=x2*err; } }; Mix::Mix(int n): N(n), x1(0), x2(0), cxt(0), pr(0) { alloc(wt, n*2); for (int i=0; i h(n) - create using n bytes n and B must be // powers of 2 with n >= B*4, and B >= 2. // h[i] returns array [1..B-1] of bytes indexed by i, creating and // replacing another element if needed. Element 0 is the // checksum and should not be modified. template class HashTable { U8* rawt; U8* t; // table: 1 element = B bytes: checksum priority data data const U32 N; // size in bytes public: HashTable(int n); ~HashTable(); U8* operator[](U32 i); }; template HashTable::HashTable(int n): t(0), N(n) { assert(B>=2 && (B&B-1)==0); assert(N>=B*4 && (N&N-1)==0); alloc(t, N+B*4+64); rawt = t; t+=64-int(((long)t)&63); // align on cache line boundary } template inline U8* HashTable::operator[](U32 i) { i*=123456791; i=i<<16|i>>16; i*=234567891; int chk=i>>24; i=i*B&N-B; if (t[i]==chk) return t+i; if (t[i^B]==chk) return t+(i^B); if (t[i^B*2]==chk) return t+(i^B*2); if (t[i+1]>t[i+1^B] || t[i+1]>t[i+1^B*2]) i^=B; if (t[i+1]>t[i+1^B^B*2]) i^=B^B*2; memset(t+i, 0, B); t[i]=chk; return t+i; } template HashTable::~HashTable() { int c=0, c0=0; for (U32 i=0; i %1.4f%% full, %1.4f%% utilized of %d KiB\n", // B, 100.0*c0*B/N, 100.0*c/N, N>>10); } ////////////////////////// LZP ///////////////////////// U32 MEM=1<<23; // Global memory limit, 1 << 22+(memory option) // LZP predicts the next byte and maintains context. Methods: // c() returns the predicted byte for the next update, or -1 if none. // p() returns the 12 bit probability (0..4095) that c() is next. // update(ch) updates the model with actual byte ch (0..255). // c(i) returns the i'th prior byte of context, i > 0. // c4() returns the order 4 context, shifted into the LSB. // c8() returns a hash of the order 8 context, shifted 4 bits into LSB. // word0, word1 are hashes of the current and previous word (a-z). class LZP { private: const int N, H; // buf, t sizes enum {MINLEN=12}; // minimum match length U8* buf; // Rotating buffer of size N U8* rawbuf; U32* t; // hash table of pointers in high 24 bits, state in low 8 bits U32* rawt; int match; // start of match int len; // length of match int pos; // position of next ch to write to buf U32 h; // context hash U32 h1; // hash of last 8 byte updates, shifting 4 bits to MSB U32 h2; // last 4 updates, shifting 8 bits to MSB StateMap sm1; // len+offset -> p APM a1, a2, a3; // p, context -> p int literals, matches; // statistics public: U32 word0, word1; // hashes of last 2 words (case insensitive a-z) LZP(); ~LZP(); int c(); // predicted char int c(int i);// context int c4() {return h2;} // order 4 context, c(1) in LSB int c8() {return h1;} // hashed order 8 context int p(); // probability that next char is c() * 4096 void update(int ch); // update model with actual char ch }; // Initialize LZP::LZP(): N(MEM/8), H(MEM/32), match(-1), len(0), pos(0), h(0), h1(0), h2(0), sm1(0x200), a1(0x10000), a2(0x40000), a3(0x100000), literals(0), matches(0), word0(0), word1(0) { assert(MEM>0); assert(H>0); alloc(buf, N); alloc(t, H); rawbuf = buf; rawt = t; } // Print statistics LZP::~LZP() { int c=0; for (int i=0; i>8, pos>10); // printf("LZP %d literals, %d matches (%1.4f%% matched)\n", // literals, matches, // literals+matches>0?100.0*matches/(literals+matches):0.0); } // Predicted next byte, or -1 for no prediction inline int LZP::c() { return len>=MINLEN ? buf[match&N-1] : -1; } // Return i'th byte of context (i > 0) inline int LZP::c(int i) { assert(i>0); return buf[pos-i&N-1]; } // Return prediction that c() will be the next byte (0..4095) int LZP::p() { if (len28) cxt=28+(len>=32)+(len>=64)+(len>=128); int pc=c(); int pr=sm1.p(cxt); pr=stretch(pr); pr=(a1.pp(2048, pr*2, h2*256+pc&0xffff)*3+pr)>>2; pr=(a2.pp(2048, pr*2, h1*(11<<6)+pc&0x3ffff)*3+pr)>>2; pr=(a3.pp(2048, pr*2, h1*(7<<4)+pc&0xfffff)*3+pr)>>2; pr=squash(pr); return pr; } // Update model with predicted byte ch (0..255) void LZP::update(int ch) { int y=c()==ch; // 1 if prediction of ch was right, else 0 h1=h1*(3<<4)+ch+1; // update context hashes h2=h2<<8|ch; h=h*(5<<2)+ch+1&H-1; if (len>=MINLEN) { sm1.update(y); a1.update(y); a2.update(y); a3.update(y); } if (isalpha(ch)) word0=word0*(29<<2)+tolower(ch); else if (word0) word1=word0, word0=0; buf[pos&N-1]=ch; // update buf ++pos; if (y) { // extend match ++len; ++match; ++matches; } else { // find new match, try order 6 context first ++literals; y=0; len=1; match=t[h]; if (!((match^pos)&N-1)) --match; while (len<=128 && buf[match-len&N-1]==buf[pos-len&N-1]) ++len; --len; } t[h]=pos; } LZP* lzp=0; //////////////////////////// Predictor ///////////////////////// // A Predictor estimates the probability that the next bit of // uncompressed data is 1. Methods: // Predictor() creates. // p() returns P(1) as a 12 bit number (0-4095). // update(y) trains the predictor with the actual bit (0 or 1). class Predictor { enum {N=11}; // number of contexts int c0; // last 0-7 bits with leading 1, 0 before LZP flag int nibble; // last 0-3 bits with leading 1 (1..15) int bcount; // number of bits in c0 (0..7) HashTable<16> t; // context -> state StateMap sm[N]; // state -> prediction U8* cp[N]; // i -> state array of bit histories for i'th context U8* sp[N]; // i -> pointer to bit history for i'th context Mix m[N-1]; // combines 2 predictions given a context APM a1, a2, a3; // adjusts a prediction given a context U8* t2; // order 1 contexts -> state U8* rawt2; public: Predictor(); ~Predictor() { if (rawt2) free(rawt2); rawt2 = t2 = 0; } int p(); void update(int y); }; // Initialize Predictor::Predictor(): c0(0), nibble(1), bcount(0), t(MEM/2), a1(0x10000), a2(0x10000), a3(0x10000) { alloc(t2, 0x40000); rawt2 = t2; for (int i=0; i=0 && bcount<8); assert(c0>=0 && c0<256); assert(nibble>=1 && nibble<=15); if (c0==0) c0=1-y; else { *sp[0]=nex(*sp[0], y); sm[0].update(y); for (int i=1; i=16) nibble=1; a1.update(y); a2.update(y); a3.update(y); } } // Predict next bit int Predictor::p() { assert(lzp); if (c0==0) return lzp->p(); else { // Set context pointers int pc=lzp->c(); // mispredicted byte int r=(pc+256)>>(8-bcount)==c0; // c0 consistent with mispredicted byte? U32 c4=lzp->c4(); // last 4 whole context bytes, shifted into LSB U32 c8=(lzp->c8()<<4)-1; // hash of last 7 bytes with 4 trailing 1 bits if ((bcount&3)==0) { // nibble boundary? Update context pointers pc&=-r; U32 c4p=c4<<8; if (bcount==0) { // byte boundary? Update order-1 context pointers cp[0]=t2+(c4>>16&0xff00); cp[1]=t2+(c4>>8 &0xff00)+0x10000; cp[2]=t2+(c4 &0xff00)+0x20000; cp[3]=t2+(c4<<8 &0xff00)+0x30000; } cp[4]=t[(c4p&0xffff00)-c0]; cp[5]=t[(c4p&0xffffff00)*3+c0]; cp[6]=t[c4*7+c0]; cp[7]=t[(c8*5&0xfffffc)+c0]; cp[8]=t[(c8*11&0xffffff0)+c0+pc*13]; cp[9]=t[lzp->word0*5+c0+pc*17]; cp[10]=t[lzp->word1*7+lzp->word0*11+c0+pc*37]; } // Mix predictions r<<=8; sp[0]=&cp[0][c0]; int pr=stretch(sm[0].p(*sp[0])); for (int i=1; i>2; } pr=(a1.pp(512, pr*2, c0+pc*256&0xffff)*3+pr)>>2; // Adjust prediction pr=(a2.pp(512, pr*2, (c4<<8&0xff00)|c0)*3+pr)>>2; pr=(a3.pp(512, pr*2, c4*3+c0&0xffff)*3+pr)>>2; return squash(pr); } } Predictor* predictor=0; /////////////////////////// get4, put4 ////////////////////////// // Read/write a 4 byte big-endian number int get4(std::istream& in) { int r; r = in.get(); r = r * 256 + in.get(); r = r * 256 + in.get(); r = r * 256 + in.get(); // char chs[4]; // std::cout << "before get4 position " << in.tellg() << '\n'; // in.read(&chs[0], 4); // std::cout << "chs " << (chs[0]&255) << " " << " " << (chs[1]&255) << " " << (chs[2]&255) << " " << (chs[3]&255) << '\n'; // std::cout << "after get4 position " << in.tellg() << '\n'; // r = ((chs[0]&255)<<24)+((chs[1]&255)<<16)+((chs[2]&255)<<8)+(chs[3]&255); // std::cout << "get4 " << r << '\n'; return r; } void put4(U32 c, std::ostream& out) { out.put(c>>24); out.put(c>>16); out.put(c>>8); out.put(c); // out << U8(c>>24) << U8(c>>16) << U8(c>>8) << U8(c); } //////////////////////////// Encoder //////////////////////////// // An Encoder arithmetic codes in blocks of size BUFSIZE. Methods: // Encoder(COMPRESS, f) creates encoder for compression to archive f, which // must be open past any header for writing in binary mode. // Encoder(DECOMPRESS, f) creates encoder for decompression from archive f, // which must be open past any header for reading in binary mode. // code(i) in COMPRESS mode compresses bit i (0 or 1) to file f. // code() in DECOMPRESS mode returns the next decompressed bit from file f. // count() should be called after each byte is compressed. // flush() should be called after compression is done. It is also called // automatically when a block is written. typedef enum {COMPRESS, DECOMPRESS} Mode; class Encoder { private: const Mode mode; // Compress or decompress? std::ostream& out; std::istream& in; U32 x1, x2; // Range, initially [0, 1), scaled by 2^32 U32 x; // Decompress mode: last 4 input bytes of archive enum {BUFSIZE=0x20000}; static unsigned char* buf; // Compression output buffer, size BUFSIZE int usize, csize; // Buffered uncompressed and compressed sizes double usum, csum; // Total of usize, csize public: Encoder(Mode m, std::istream& in, std::ostream& out); ~Encoder() { if (buf) free(buf); buf = 0; } void flush(); // call this when compression is finished // Compress bit y or return decompressed bit int code(int y=0) { assert(predictor); int p=predictor->p(); assert(p>=0 && p<4096); p+=p<2048; U32 xmid=x1 + ((x2-x1)>>12)*p + ((x2-x1&0xfff)*p>>12); assert(xmid>=x1 && xmidupdate(y); while (((x1^x2)&0xff000000)==0) { // pass equal leading bytes of range if (mode==COMPRESS) buf[csize++]=x2>>24; x1<<=8; x2=(x2<<8)+255; if (mode==DECOMPRESS) x=(x<<8)+in.get(); } return y; } // Count one byte void count() { assert(mode==COMPRESS); ++usize; if (csize>BUFSIZE-256) flush(); } }; unsigned char* Encoder::buf=0; // Create in mode m (COMPRESS or DECOMPRESS) with f opened as the archive. Encoder::Encoder(Mode m, std::istream& sin, std::ostream& sout): mode(m), out(sout), in(sin), x1(0), x2(0xffffffff), x(0), usize(0), csize(0), usum(0), csum(0) { if (mode==DECOMPRESS) { // x = first 4 bytes of archive for (int i=0; i<4; ++i) x=(x<<8)+(in.get()&255); csize=4; } else if (!buf) alloc(buf, BUFSIZE); } // Write a compressed block and reinitialize the encoder. The format is: // uncompressed size (usize, 4 byte, MSB first) // compressed size (csize, 4 bytes, MSB first) // compressed data (csize bytes) void Encoder::flush() { if (mode==COMPRESS) { buf[csize++]=x1>>24; buf[csize++]=255; buf[csize++]=255; buf[csize++]=255; out.put(char(0)); out.put('c'); put4(usize, out); put4(csize, out); out.write((char *)buf, csize); usum+=usize; csum+=csize+10; // printf("%15.0f -> %15.0f" // "\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b\b", // usum, csum); x1=x=usize=csize=0; x2=0xffffffff; } } /////////////////////////// paq9a //////////////////////////////// // Compress or decompress from in to out, depending on whether mode // is COMPRESS or DECOMPRESS. A byte c is encoded as a 1 bit if it // is predicted by LZP, otherwise a 0 followed by 8 bits from MSB to LSB. void paq9a(std::istream& in, std::ostream& out, Mode mode) { if (!lzp && !predictor) { lzp=new LZP; predictor=new Predictor; // printf("%8d KiB\b\b\b\b\b\b\b\b\b\b\b\b", allocated>>10); } std::istringstream emptyin; std::ostringstream emptyout; if (mode==COMPRESS) { Encoder e(COMPRESS, emptyin, out); int c; while ((c=in.get())!=EOF) { int cp=lzp->c(); if (c==cp) e.code(1); else for (int i=8; i>=0; --i) e.code(c>>i&1); e.count(); lzp->update(c); } e.flush(); } else { // DECOMPRESS int usize=get4(in); get4(in); // csize Encoder e(DECOMPRESS, in, emptyout); while (usize--) { int c=lzp->c(); if (e.code()==0) { c=1; while (c<256) c+=c+e.code(); c&=255; } out.put(char(c)); lzp->update(c); } } } void reset() { if (lzp) delete lzp; if (predictor) delete predictor; lzp = 0; predictor = 0; allocated = 0; } std::string compress_string(std::string& in) { std::istringstream sin(in); std::ostringstream sout; paq9a(sin, sout, COMPRESS); reset(); return sout.str(); } std::string decompress_string(std::string &in) { std::istringstream sin(in); std::ostringstream sout; char ch; sin>>ch; // ch = 0; // std::cout << "should be 0 " << U32(ch&255) << '\n'; // std::cout << "before while position " << sin.tellg() << '\n'; while (sin>>ch) { // now ch = 'c'; // std::cout << "should be c " << ch << '\n'; // std::cout << "before position " << sin.tellg() << '\n'; paq9a(sin, sout, DECOMPRESS); // std::cout << "after position " << sin.tellg() << '\n'; sin>>ch; } reset(); return sout.str(); } paq-master/paq/_paq.pyx0000644000175000017500000000055613134607302013472 0ustar jdgjdgfrom libcpp.string cimport string cdef extern from "paq9a.h": string compress_string(string&) string decompress_string(string&) def compress(bytes data): cdef string s = data cdef bytes r = compress_string(s) return r def decompress(bytes data): cdef string s = data[:len(data)] cdef bytes r = decompress_string(s) return r paq-master/paq/__init__.py0000644000175000017500000000005313134607302014111 0ustar jdgjdgfrom ._paq import * __version__ = '0.1.1' paq-master/.gitignore0000644000175000017500000000220513134607302013210 0ustar jdgjdg# Byte-compiled / optimized / DLL files __pycache__/ *.py[cod] *$py.class # C extensions *.so # Distribution / packaging .Python env/ build/ develop-eggs/ dist/ downloads/ eggs/ .eggs/ lib/ lib64/ parts/ sdist/ var/ wheels/ *.egg-info/ .installed.cfg *.egg # PyInstaller # Usually these files are written by a python script from a template # before PyInstaller builds the exe, so as to inject date/other infos into it. *.manifest *.spec # Installer logs pip-log.txt pip-delete-this-directory.txt # Unit test / coverage reports htmlcov/ .tox/ .coverage .coverage.* .cache nosetests.xml coverage.xml *.cover .hypothesis/ # Translations *.mo *.pot # Django stuff: *.log local_settings.py # Flask stuff: instance/ .webassets-cache # Scrapy stuff: .scrapy # Sphinx documentation docs/_build/ # PyBuilder target/ # Jupyter Notebook .ipynb_checkpoints # pyenv .python-version # celery beat schedule file celerybeat-schedule # SageMath parsed files *.sage.py # dotenv .env # virtualenv .venv venv/ ENV/ # Spyder project settings .spyderproject .spyproject # Rope project settings .ropeproject # mkdocs documentation /site # mypy .mypy_cache/ paq-master/LICENSE0000644000175000017500000000205413134607302012227 0ustar jdgjdgMIT License Copyright (c) 2017 Jingchao Hu Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. paq-master/MANIFEST.in0000644000175000017500000000004213134607302012753 0ustar jdgjdginclude paq/*.h include paq/*.pyx paq-master/requirements.txt0000644000175000017500000000000713134607302014502 0ustar jdgjdgcython