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fpng.cpp
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// fpng.cpp 1.0.6 - Fast 24/32bpp .PNG image writer/reader. See unlicense at the end of this file.
// PNG's generated by this code have been tested to load successfully with stb_image.h, lodepng.cpp, wuffs, libpng, and pngcheck.
//
// Uses code from the simple PNG writer function by Alex Evans, 2011. Released into the public domain: https://gist.github.com/908299
// Some low-level Deflate/Huffman functions derived from the original 2011 Google Code version of miniz (public domain by R. Geldreich, Jr.): https://code.google.com/archive/p/miniz/
// Low-level Huffman code size function: public domain, originally written by: Alistair Moffat, [email protected], Jyrki Katajainen, [email protected], November 1996.
//
// Optional config macros:
// FPNG_NO_SSE - Set to 1 to completely disable SSE usage, even on x86/x64. By default, on x86/x64 it's enabled.
// FPNG_DISABLE_DECODE_CRC32_CHECKS - Set to 1 to disable PNG chunk CRC-32 tests, for improved fuzzing. Defaults to 0.
// FPNG_USE_UNALIGNED_LOADS - Set to 1 to indicate it's OK to read/write unaligned 32-bit/64-bit values. Defaults to 0, unless x86/x64.
//
// With gcc/clang on x86, compile with -msse4.1 -mpclmul -fno-strict-aliasing
// Only tested with -fno-strict-aliasing (which the Linux kernel uses, and MSVC's default).
//
#include "fpng.h"
#include <assert.h>
#include <string.h>
#ifdef _MSC_VER
#pragma warning (disable:4127) // conditional expression is constant
#endif
// Set FPNG_NO_SSE to 1 to completely disable SSE usage.
#ifndef FPNG_NO_SSE
#define FPNG_NO_SSE (0)
#endif
// Detect if we're compiling on x86/x64
#if defined(_M_IX86) || defined(_M_X64) || defined(__i386__) || defined(__i386) || defined(__i486__) || defined(__i486) || defined(i386) || defined(__ia64__) || defined(__x86_64__)
#define FPNG_X86_OR_X64_CPU (1)
#else
#define FPNG_X86_OR_X64_CPU (0)
#endif
#if FPNG_X86_OR_X64_CPU && !FPNG_NO_SSE
#ifdef _MSC_VER
#include <intrin.h>
#endif
#include <xmmintrin.h> // SSE
#include <emmintrin.h> // SSE2
#include <smmintrin.h> // SSE4.1
#include <wmmintrin.h> // pclmul
#endif
#ifndef FPNG_NO_STDIO
#include <stdio.h>
#endif
// Allow the disabling of the chunk data CRC32 checks, for fuzz testing of the decoder
#ifndef FPNG_DISABLE_DECODE_CRC32_CHECKS
#define FPNG_DISABLE_DECODE_CRC32_CHECKS (0)
#endif
// Using unaligned loads and stores causes errors when using UBSan. Jam it off.
#if defined(__has_feature)
#if __has_feature(undefined_behavior_sanitizer)
#undef FPNG_USE_UNALIGNED_LOADS
#define FPNG_USE_UNALIGNED_LOADS (0)
#endif
#endif
// Set to 0 if your platform doesn't support unaligned 32-bit/64-bit reads/writes.
#ifndef FPNG_USE_UNALIGNED_LOADS
#if FPNG_X86_OR_X64_CPU
// On x86/x64 we default to enabled, for a noticeable perf gain.
#define FPNG_USE_UNALIGNED_LOADS (1)
#else
#define FPNG_USE_UNALIGNED_LOADS (0)
#endif
#endif
#if defined(_MSC_VER) || defined(__MINGW32__) || FPNG_X86_OR_X64_CPU
#ifndef __LITTLE_ENDIAN
#define __LITTLE_ENDIAN 1234
#endif
#ifndef __BIG_ENDIAN
#define __BIG_ENDIAN 4321
#endif
// Assume little endian on Windows/x86/x64.
#define __BYTE_ORDER __LITTLE_ENDIAN
#elif defined(__APPLE__)
#define __BYTE_ORDER __BYTE_ORDER__
#define __LITTLE_ENDIAN __LITTLE_ENDIAN__
#define __BIG_ENDIAN __BIG_ENDIAN__
#else
// for __BYTE_ORDER (__LITTLE_ENDIAN or __BIG_ENDIAN)
#include <sys/param.h>
#ifndef __LITTLE_ENDIAN
#define __LITTLE_ENDIAN 1234
#endif
#ifndef __BIG_ENDIAN
#define __BIG_ENDIAN 4321
#endif
#endif
#if !defined(__BYTE_ORDER)
#error __BYTE_ORDER undefined. Compile with -D__BYTE_ORDER=1234 for little endian or -D__BYTE_ORDER=4321 for big endian.
#endif
// NOTE: globed addition
#if defined(__clang__) || defined(__GNUC__)
# define FPNG_SSE41 __attribute__((__target__("sse4.1")))
# define FPNG_PCLMUL __attribute__((__target__("pclmul")))
#else // __clang__
// on msvc there's no need to set these
# define FPNG_SSE41
# define FPNG_PCLMUL
#endif // __clang__
// NOTE: end globed addition
namespace fpng
{
static const int FPNG_FALSE = 0;
static const uint8_t FPNG_FDEC_VERSION = 0;
static const uint32_t FPNG_MAX_SUPPORTED_DIM = 1 << 24;
template <typename S> static inline S maximum(S a, S b) { return (a > b) ? a : b; }
template <typename S> static inline S minimum(S a, S b) { return (a < b) ? a : b; }
static inline uint32_t simple_swap32(uint32_t x) { return (x >> 24) | ((x >> 8) & 0x0000FF00) | ((x << 8) & 0x00FF0000) | (x << 24); }
static inline uint64_t simple_swap64(uint64_t x) { return (((uint64_t)simple_swap32((uint32_t)x)) << 32U) | simple_swap32((uint32_t)(x >> 32U)); }
static inline uint32_t swap32(uint32_t x)
{
#if defined(__GNUC__) || defined(__clang__)
return __builtin_bswap32(x);
#else
return simple_swap32(x);
#endif
}
static inline uint64_t swap64(uint64_t x)
{
#if defined(__GNUC__) || defined(__clang__)
return __builtin_bswap64(x);
#else
return simple_swap64(x);
#endif
}
#if FPNG_USE_UNALIGNED_LOADS
#if __BYTE_ORDER == __BIG_ENDIAN
#define READ_LE32(p) swap32(*reinterpret_cast<const uint32_t *>(p))
#define WRITE_LE32(p, v) *reinterpret_cast<uint32_t *>(p) = swap32((uint32_t)(v))
#define WRITE_LE64(p, v) *reinterpret_cast<uint64_t *>(p) = swap64((uint64_t)(v))
#define READ_BE32(p) *reinterpret_cast<const uint32_t *>(p)
#else
#define READ_LE32(p) (*reinterpret_cast<const uint32_t *>(p))
#define WRITE_LE32(p, v) *reinterpret_cast<uint32_t *>(p) = (uint32_t)(v)
#define WRITE_LE64(p, v) *reinterpret_cast<uint64_t *>(p) = (uint64_t)(v)
#define READ_BE32(p) swap32(*reinterpret_cast<const uint32_t *>(p))
#endif
#else
// A good compiler should be able to optimize these routines - hopefully. They are crucial for performance.
static inline uint32_t READ_LE32(const void* p)
{
const uint8_t* pBytes = (const uint8_t*)p;
return ((uint32_t)pBytes[0]) | (((uint32_t)pBytes[1]) << 8U) | (((uint32_t)pBytes[2]) << 16U) | (((uint32_t)pBytes[3]) << 24U);
}
static inline uint32_t READ_BE32(const void* p)
{
const uint8_t* pBytes = (const uint8_t*)p;
return ((uint32_t)pBytes[3]) | (((uint32_t)pBytes[2]) << 8U) | (((uint32_t)pBytes[1]) << 16U) | (((uint32_t)pBytes[0]) << 24U);
}
static inline void WRITE_LE32(const void* p, uint32_t v)
{
uint8_t* pBytes = (uint8_t*)p;
pBytes[0] = (uint8_t)(v);
pBytes[1] = (uint8_t)(v >> 8);
pBytes[2] = (uint8_t)(v >> 16);
pBytes[3] = (uint8_t)(v >> 24);
}
static inline void WRITE_LE64(const void* p, uint64_t v)
{
uint8_t* pBytes = (uint8_t*)p;
pBytes[0] = (uint8_t)(v);
pBytes[1] = (uint8_t)(v >> 8);
pBytes[2] = (uint8_t)(v >> 16);
pBytes[3] = (uint8_t)(v >> 24);
pBytes[4] = (uint8_t)(v >> 32);
pBytes[5] = (uint8_t)(v >> 40);
pBytes[6] = (uint8_t)(v >> 48);
pBytes[7] = (uint8_t)(v >> 56);
}
#endif
// Customized the very common case of reading a 24bpp pixel from memory
static inline uint32_t READ_RGB_PIXEL(const void* p)
{
#if FPNG_USE_UNALIGNED_LOADS
return READ_LE32(p) & 0xFFFFFF;
#else
const uint8_t* pBytes = (const uint8_t*)p;
return ((uint32_t)pBytes[0]) | (((uint32_t)pBytes[1]) << 8U) | (((uint32_t)pBytes[2]) << 16U);
#endif
}
// See "Slicing by 4" CRC-32 algorithm here:
// https://create.stephan-brumme.com/crc32/
// Precomputed 4KB of CRC-32 tables
static const uint32_t g_crc32_4[4][256] = {
{00, 016701630226, 035603460454, 023102250672, 0733342031, 016032572217, 035130722465, 023631112643, 01666704062, 017167134244, 034065364436, 022764554610, 01155446053, 017654276275, 034756026407, 022057616621, 03555610144, 015254020362, 036356270510, 020457440736, 03266552175, 015567362353, 036465132521, 020364702707, 02333114126, 014432724300, 037530574572, 021231344754, 02400256117, 014301466331, 037203636543, 021502006765,
07333420310, 011432210136, 032530040744, 024231670562, 07400762321, 011301152107, 032203302775, 024502532553, 06555324372, 010254514154, 033356744726, 025457174500, 06266066343, 010567656165, 033465406717, 025364236531, 04666230254, 012167400072, 031065650600, 027764060426, 04155172265, 012654742043, 031756512631, 027057322417, 05000534236, 013701304010, 030603154662, 026102764444, 05733676207, 013032046021, 030130216653, 026631426475,
016667040620, 0166670406, 023064420274, 035765210052, 016154302611, 0655532437, 023757762245, 035056152063, 017001744642, 01700174464, 022602324216, 034103514030, 017732406673, 01033236455, 022131066227, 034630656001, 015332650764, 03433060542, 020531230330, 036230400116, 015401512755, 03300322573, 020202172301, 036503742127, 014554154706, 02255764520, 021357534352, 037456304174, 014267216737, 02566426511, 021464676363, 037365046145,
011554460530, 07255250716, 024357000164, 032456630342, 011267722501, 07566112727, 024464342155, 032365572373, 010332364552, 06433554774, 025531704106, 033230134320, 010401026563, 06300616745, 025202446137, 033503276311, 012001270474, 04700440652, 027602610020, 031103020206, 012732132445, 04033702663, 027131552011, 031630362237, 013667574416, 05166344630, 026064114042, 030765724264, 013154636427, 05655006601, 026757256073, 030056466255,
035556101440, 023257731666, 0355561014, 016454351232, 035265243471, 023564473657, 0466623025, 016367013203, 034330605422, 022431035604, 01533265076, 017232455250, 034403547413, 022302377635, 01200127047, 017501717261, 036003711504, 020702121722, 03600371150, 015101541376, 036730453535, 020031263713, 03133033161, 015632603347, 037665015566, 021164625740, 02066475132, 014767245314, 037156357557, 021657567771, 02755737103, 014054107325,
032665521750, 024164311576, 07066141304, 011767771122, 032156663761, 024657053547, 07755203335, 011054433113, 033003225732, 025702415514, 06600645366, 010101075140, 033730167703, 025031757525, 06133507357, 010632337171, 031330331614, 027431501432, 04533751240, 012232161066, 031403073625, 027302643403, 04200413271, 012501223057, 030556435676, 026257205450, 05355055222, 013454665004, 030265777647, 026564147461, 05466317213, 013367527035,
023331141260, 035430771046, 016532521634, 0233311412, 023402203251, 035303433077, 016201663605, 0500053423, 022557645202, 034256075024, 017354225656, 01455415470, 022264507233, 034565337015, 017467167667, 01366757441, 020664751324, 036165161102, 015067331770, 03766501556, 020157413315, 036656223133, 015754073741, 03055643567, 021002055346, 037703665160, 014601435712, 02100205534, 021731317377, 037030527151, 014132777723, 02633147505,
024002561170, 032703351356, 011601101524, 07100731702, 024731623141, 032030013367, 011132243515, 07633473733, 025664265112, 033165455334, 010067605546, 06766035760, 025157127123, 033656717305, 010754547577, 06055377751, 027557371034, 031256541212, 012354711460, 04455121646, 027264033005, 031565603223, 012467453451, 04366263677, 026331475056, 030430245270, 013532015402, 05233625624, 026402737067, 030303107241, 013201357433, 05500567615,
}, { 00,03106630501,06215461202,05313251703,014433142404,017535772105,012626523606,011720313307,031066305010,032160535511,037273764212,034375154713,025455247414,026553477115,023640626616,020746016317,011260411121,012366221420,017075070323,014173640622,05653553525,06755363024,03446132727,0540702226,020206714131,023300124430,026013375333,025115545632,034635656535,037733066034,032420237737,031526407236,
022541022242,021447612743,024754443040,027652273541,036172160646,035074750347,030367501444,033261331145,013527327252,010421517753,015732746050,016634176551,07114265656,04012455357,01301604454,02207034155,033721433363,030627203662,035534052161,036432662460,027312571767,024214341266,021107110565,022001720064,02747736373,01641106672,04552357171,07454567470,016374674777,015272044276,010161215575,013067425074,
036036247405,035130477104,030223626607,033325016306,022405305001,021503535500,024610764203,027716154702,07050142415,04156772114,01245523617,02343313316,013463000011,010565630510,015676461213,016770251712,027256656524,024350066025,021043237726,022145407227,033665714120,030763124421,035470375322,036576545623,016230553534,015336363035,010025132736,013123702237,02603411130,01705221431,04416070332,07510640633,
014577265647,017471455346,012762604445,011664034144,0144327243,03042517742,06351746041,05257176540,025511160657,026417750356,023704501455,020602331154,031122022253,032024612752,037337443051,034231273550,05717674766,06611044267,03502215564,0404425065,011324736362,012222106663,017131357160,014037567461,034771571776,037677341277,032564110574,031462720075,020342433372,023244203673,026157052170,025051662471,
07340714113,04246124412,01155375311,02053545610,013773656517,010675066016,015566237715,016460407214,036326411103,035220221402,030133070301,033035640600,022715553507,021613363006,024500132705,027406702204,016120305032,015026535533,010335764230,013233154731,02513247436,01415477137,04706626634,07600016335,027146000022,024040630523,021353461220,022255251721,033575142426,030473772127,035760523624,036666313325,
025601736351,026707106650,023414357153,020512567452,031232674755,032334044254,037027215557,034121425056,014667433341,017761203640,012472052143,011574662442,0254571745,03352341244,06041110547,05147720046,034461327270,037567517771,032674746072,031772176573,020052265674,023154455375,026247604476,025341034177,05407022260,06501612761,03612443062,0714273563,011034160664,012132750365,017221501466,014327331167,
031376553516,032270363017,037163132714,034065702215,025745411112,026643221413,023550070310,020456640611,0310656506,03216066007,06105237704,05003407205,014723714102,017625124403,012536375300,011430545601,020116142437,023010772136,026303523635,025205313334,034525000033,037423630532,032730461231,031636251730,011170247427,012076477126,017365626625,014263016324,05543305023,06445535522,03756764221,0650154720,
013637571754,010731341255,015422110556,016524720057,07204433350,04302203651,01011052152,02117662453,022651674744,021757044245,024444215546,027542425047,036262736340,035364106641,030077357142,033171567443,02457160675,01551750374,04642501477,07744331176,016064022271,015162612770,010271443073,013377273572,033431265665,030537455364,035624604467,036722034166,027002327261,024104517760,021217746063,022311176562,
}, { 00,0160465067,0341152156,0221537131,0702324334,0662741353,0443276262,0523613205,01604650670,01764235617,01545702726,01425367741,01106574544,01066111523,01247426412,01327043475,03411521560,03571144507,03750473436,03630016451,03313605654,03273260633,03052757702,03132332765,02215371310,02375714377,02154223246,02034646221,02517055024,02477430043,02656107172,02736562115,
07023243340,07143626327,07362311216,07202774271,07721167074,07641502013,07460035122,07500450145,06627413530,06747076557,06566541466,06406124401,06125737604,06045352663,06264665752,06304200735,04432762620,04552307647,04773630776,04613255711,04330446514,04250023573,04071514442,04111171425,05236132050,05356557037,05177060106,05017405161,05534216364,05454673303,05675344232,05715721255,
016046506700,016126163767,016307454656,016267031631,016744622434,016624247453,016405770562,016565315505,017642356170,017722733117,017503204026,017463661041,017140072244,017020417223,017201120312,017361545375,015457027260,015537442207,015716175336,015676510351,015355303154,015235766133,015014251002,015174634065,014253677410,014333212477,014112725546,014072340521,014551553724,014431136743,014610401672,014770064615,
011065745440,011105320427,011324617516,011244272571,011767461774,011607004713,011426533622,011546156645,010661115230,010701570257,010520047366,010440422301,010163231104,010003654163,010222363052,010342706035,012474264120,012514601147,012735336076,012655753011,012376140214,012216525273,012037012342,012157477325,013270434750,013310051737,013131566606,013051103661,013572710464,013412375403,013633642532,013753227555,
034115215600,034075670667,034254347756,034334722731,034617131534,034777554553,034556063462,034436406405,035711445070,035671020017,035450517126,035530172141,035013761344,035173304323,035352633212,035232256275,037504734360,037464351307,037645666236,037725203251,037206410054,037366075033,037147542102,037027127165,036300164510,036260501577,036041036446,036121453421,036402240624,036562625643,036743312772,036623777715,
033136056540,033056433527,033277104416,033317561471,033634372674,033754717613,033575220722,033415645745,032732606330,032652263357,032473754266,032513331201,032030522004,032150147063,032371470152,032211015135,030527577020,030447112047,030666425176,030706040111,030225653314,030345236373,030164701242,030004364225,031323327650,031243742637,031062275706,031102610761,031421003564,031541466503,031760151432,031600534455,
022153713100,022033376167,022212641056,022372224031,022651437234,022731052253,022510565362,022470100305,023757143770,023637526717,023416011626,023576474641,023055267444,023135602423,023314335512,023274750575,021542232460,021422657407,021603360536,021763705551,021240116754,021320573733,021101044602,021061421665,020346462210,020226007277,020007530346,020167155321,020444746124,020524323143,020705614072,020665271015,
025170550240,025010135227,025231402316,025351067371,025672674174,025712211113,025533726022,025453343045,024774300430,024614765457,024435252566,024555637501,024076024704,024116441763,024337176652,024257513635,026561071720,026401414747,026620123676,026740546611,026263355414,026303730473,026122207542,026042662525,027365621150,027205244137,027024773006,027144316061,027467505264,027507160203,027726457332,027646032355,
}, { 00,027057063545,025202344213,02255327756,021730513527,06767570062,04532657734,023565634271,030555024357,017502047612,015757360144,032700303401,011265537670,036232554335,034067673463,013030610126,012006253637,035051230372,037204117424,010253174161,033736740310,014761723655,016534404103,031563467446,022553277560,05504214025,07751133773,020706150236,03263764047,024234707502,026061420254,01036443711,
024014527476,03043544133,01216663665,026241600320,05724034151,022773057414,020526370342,07571313607,014541503721,033516560264,031743647532,016714624077,035271010206,012226073743,010073354015,037024337550,036012774241,011045717704,013210430052,034247453517,017722267766,030775204223,032520123575,015577140030,06547750116,021510733453,023745414305,04712477640,027277243431,0220220174,02075107622,025022164367,
023305054075,04352037530,06107310266,021150373723,02435547552,025462524017,027637603741,0660660204,013650070322,034607013667,036452334131,011405357474,032160563605,015137500340,017362627416,030335644153,031303207642,016354264307,014101143451,033156120114,010433714365,037464777620,035631450176,012666433433,01656223515,026601240050,024454167706,03403104243,020166730032,07131753577,05364474221,022333417764,
07311573403,020346510146,022113637610,05144654355,026421060124,01476003461,03623324337,024674347672,037644557754,010613534211,012446613547,035411670002,016174044273,031123027736,033376300060,014321363525,015317720234,032340743771,030115464027,017142407562,034427233713,013470250256,011625177500,036672114045,025642704163,02615767426,0440440370,027417423635,04172217444,023125274101,021370153657,06327130312,
035526333073,012571350536,010724077260,037773014725,014216620554,033241643011,031014564747,016043507202,05073317324,022024374661,020271053137,07226030472,024743604603,03714667346,01541540410,026516523155,027520160644,0577103301,02722224457,025775247112,06210473363,021247410626,023012737170,04045754435,017075144513,030022127056,032277200700,015220263245,036745457034,011712434571,013547713227,034510770762,
011532614405,036565677140,034730550616,013767533353,030202307122,017255364467,015000043331,032057020674,021067630752,06030653217,04265574541,023232517004,0757323275,027700340730,025555067066,02502004523,03534447232,024563424777,026736703021,01761760564,022204154715,05253137250,07006210506,020051273043,033061463165,014036400420,016263727376,031234744633,012751170442,035706113107,037553234651,010504257314,
016623367006,031674304543,033421023215,014476040750,037113674521,010144617064,012311530732,035346553277,026376343351,01321320614,03174007142,024123064407,07446650676,020411633333,022644514465,05613577120,04625134631,023672157374,021427270422,06470213167,025115427316,02142444653,0317763105,027340700440,034370110566,013327173023,011172254775,036125237230,015440403041,032417460504,030642747252,017615724717,
032637640470,015660623135,017435504663,030462567326,013107353157,034150330412,036305017344,011352074601,02362664727,025335607262,027160520534,0137543071,023452377200,04405314745,06650033013,021607050556,020631413247,07666470702,05433757054,022464734511,01101100760,026156163225,024303244573,03354227036,010364437110,037333454455,035166773303,012131710646,031454124437,016403147172,014656260624,033601203361,
} };
static uint32_t crc32_slice_by_4(const void* pData, size_t data_len, uint32_t cur_crc32 = 0)
{
uint32_t crc = ~cur_crc32;
const uint32_t* pData32 = static_cast<const uint32_t*>(pData);
for (; data_len >= sizeof(uint32_t); ++pData32, data_len -= 4)
{
uint32_t v = READ_LE32(pData32) ^ crc;
crc = g_crc32_4[0][v >> 24] ^ g_crc32_4[1][(v >> 16) & 0xFF] ^ g_crc32_4[2][(v >> 8) & 0xFF] ^ g_crc32_4[3][v & 0xFF];
}
for (const uint8_t* pData8 = reinterpret_cast<const uint8_t*>(pData32); data_len; --data_len)
crc = (crc >> 8) ^ g_crc32_4[0][(crc & 0xFF) ^ *pData8++];
return ~crc;
}
#if FPNG_X86_OR_X64_CPU && !FPNG_NO_SSE
// See Fast CRC Computation for Generic Polynomials Using PCLMULQDQ Instruction":
// https://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf
// Requires PCLMUL and SSE 4.1. This function skips Step 1 (fold by 4) for simplicity/less code.
static uint32_t FPNG_PCLMUL crc32_pclmul(const uint8_t* p, size_t size, uint32_t crc)
{
assert(size >= 16);
// See page 22 (bit reflected constants for gzip)
#ifdef _MSC_VER
static const uint64_t __declspec(align(16))
#else
static const uint64_t __attribute__((aligned(16)))
#endif
s_u[2] = { 0x1DB710641, 0x1F7011641 }, s_k5k0[2] = { 0x163CD6124, 0 }, s_k3k4[2] = { 0x1751997D0, 0xCCAA009E };
// Load first 16 bytes, apply initial CRC32
__m128i b = _mm_xor_si128(_mm_cvtsi32_si128(~crc), _mm_loadu_si128(reinterpret_cast<const __m128i*>(p)));
// We're skipping directly to Step 2 page 12 - iteratively folding by 1 (by 4 is overkill for our needs)
const __m128i k3k4 = _mm_load_si128(reinterpret_cast<const __m128i*>(s_k3k4));
for (size -= 16, p += 16; size >= 16; size -= 16, p += 16)
b = _mm_xor_si128(_mm_xor_si128(_mm_clmulepi64_si128(b, k3k4, 17), _mm_loadu_si128(reinterpret_cast<const __m128i*>(p))), _mm_clmulepi64_si128(b, k3k4, 0));
// Final stages: fold to 64-bits, 32-bit Barrett reduction
const __m128i z = _mm_set_epi32(0, ~0, 0, ~0), u = _mm_load_si128(reinterpret_cast<const __m128i*>(s_u));
b = _mm_xor_si128(_mm_srli_si128(b, 8), _mm_clmulepi64_si128(b, k3k4, 16));
b = _mm_xor_si128(_mm_clmulepi64_si128(_mm_and_si128(b, z), _mm_loadl_epi64(reinterpret_cast<const __m128i*>(s_k5k0)), 0), _mm_srli_si128(b, 4));
return ~_mm_extract_epi32(_mm_xor_si128(b, _mm_clmulepi64_si128(_mm_and_si128(_mm_clmulepi64_si128(_mm_and_si128(b, z), u, 16), z), u, 0)), 1);
}
static uint32_t crc32_sse41_simd(const unsigned char* buf, size_t len, uint32_t prev_crc32)
{
if (len < 16)
return crc32_slice_by_4(buf, len, prev_crc32);
uint32_t simd_len = len & ~15;
uint32_t c = crc32_pclmul(buf, simd_len, prev_crc32);
return crc32_slice_by_4(buf + simd_len, len - simd_len, c);
}
#endif
#if FPNG_X86_OR_X64_CPU && !FPNG_NO_SSE
#ifndef _MSC_VER
static void do_cpuid(uint32_t eax, uint32_t ecx, uint32_t* regs)
{
uint32_t ebx = 0, edx = 0;
#if defined(__PIC__) && defined(__i386__)
__asm__("movl %%ebx, %%edi;"
"cpuid;"
"xchgl %%ebx, %%edi;"
: "=D"(ebx), "+a"(eax), "+c"(ecx), "=d"(edx));
#else
__asm__("cpuid;" : "+b"(ebx), "+a"(eax), "+c"(ecx), "=d"(edx));
#endif
regs[0] = eax; regs[1] = ebx; regs[2] = ecx; regs[3] = edx;
}
#endif
struct cpu_info
{
cpu_info() { memset(this, 0, sizeof(*this)); }
bool m_initialized, m_has_fpu, m_has_mmx, m_has_sse, m_has_sse2, m_has_sse3, m_has_ssse3, m_has_sse41, m_has_sse42, m_has_avx, m_has_avx2, m_has_pclmulqdq;
void init()
{
if (m_initialized)
return;
int regs[4];
#ifdef _MSC_VER
__cpuid(regs, 0);
#else
do_cpuid(0, 0, (uint32_t*)regs);
#endif
const uint32_t max_eax = regs[0];
if (max_eax >= 1U)
{
#ifdef _MSC_VER
__cpuid(regs, 1);
#else
do_cpuid(1, 0, (uint32_t*)regs);
#endif
extract_x86_flags(regs[2], regs[3]);
}
if (max_eax >= 7U)
{
#ifdef _MSC_VER
__cpuidex(regs, 7, 0);
#else
do_cpuid(7, 0, (uint32_t*)regs);
#endif
extract_x86_extended_flags(regs[1]);
}
m_initialized = true;
}
bool can_use_sse41() const { return m_has_sse && m_has_sse2 && m_has_sse3 && m_has_ssse3 && m_has_sse41; }
bool can_use_pclmul() const { return m_has_pclmulqdq && can_use_sse41(); }
private:
void extract_x86_flags(uint32_t ecx, uint32_t edx)
{
m_has_fpu = (edx & (1 << 0)) != 0; m_has_mmx = (edx & (1 << 23)) != 0; m_has_sse = (edx & (1 << 25)) != 0; m_has_sse2 = (edx & (1 << 26)) != 0;
m_has_sse3 = (ecx & (1 << 0)) != 0; m_has_ssse3 = (ecx & (1 << 9)) != 0; m_has_sse41 = (ecx & (1 << 19)) != 0; m_has_sse42 = (ecx & (1 << 20)) != 0;
m_has_pclmulqdq = (ecx & (1 << 1)) != 0; m_has_avx = (ecx & (1 << 28)) != 0;
}
void extract_x86_extended_flags(uint32_t ebx) { m_has_avx2 = (ebx & (1 << 5)) != 0; }
};
cpu_info g_cpu_info;
void fpng_init()
{
g_cpu_info.init();
}
#else
void fpng_init()
{
}
#endif
bool fpng_cpu_supports_sse41()
{
#if FPNG_X86_OR_X64_CPU && !FPNG_NO_SSE
assert(g_cpu_info.m_initialized);
return g_cpu_info.can_use_sse41();
#else
return false;
#endif
}
uint32_t fpng_crc32(const void* pData, size_t size, uint32_t prev_crc32)
{
#if FPNG_X86_OR_X64_CPU && !FPNG_NO_SSE
if (g_cpu_info.can_use_pclmul())
return crc32_sse41_simd(static_cast<const uint8_t *>(pData), size, prev_crc32);
#endif
return crc32_slice_by_4(pData, size, prev_crc32);
}
#if FPNG_X86_OR_X64_CPU && !FPNG_NO_SSE
// See "Fast Computation of Adler32 Checksums":
// https://www.intel.com/content/www/us/en/developer/articles/technical/fast-computation-of-adler32-checksums.html
// SSE 4.1, 16 bytes per iteration
static uint32_t FPNG_SSE41 adler32_sse_16(const uint8_t* p, size_t len, uint32_t initial)
{
uint32_t s1 = initial & 0xFFFF, s2 = initial >> 16;
const uint32_t K = 65521;
while (len >= 16)
{
__m128i a = _mm_setr_epi32(s1, 0, 0, 0), b = _mm_setzero_si128(), c = _mm_setzero_si128(), d = _mm_setzero_si128(),
e = _mm_setzero_si128(), f = _mm_setzero_si128(), g = _mm_setzero_si128(), h = _mm_setzero_si128();
const size_t n = minimum<size_t>(len >> 4, 5552);
for (size_t i = 0; i < n; i++)
{
const __m128i v = _mm_loadu_si128((const __m128i*)(p + i * 16));
a = _mm_add_epi32(a, _mm_cvtepu8_epi32(_mm_shuffle_epi32(v, _MM_SHUFFLE(0, 0, 0, 0)))); b = _mm_add_epi32(b, a);
c = _mm_add_epi32(c, _mm_cvtepu8_epi32(_mm_shuffle_epi32(v, _MM_SHUFFLE(1, 1, 1, 1)))); d = _mm_add_epi32(d, c);
e = _mm_add_epi32(e, _mm_cvtepu8_epi32(_mm_shuffle_epi32(v, _MM_SHUFFLE(2, 2, 2, 2)))); f = _mm_add_epi32(f, e);
g = _mm_add_epi32(g, _mm_cvtepu8_epi32(_mm_shuffle_epi32(v, _MM_SHUFFLE(3, 3, 3, 3)))); h = _mm_add_epi32(h, g);
}
uint32_t sa[16], sb[16];
_mm_storeu_si128((__m128i*)sa, a); _mm_storeu_si128((__m128i*)(sa + 4), c);
_mm_storeu_si128((__m128i*)sb, b); _mm_storeu_si128((__m128i*)(sb + 4), d);
_mm_storeu_si128((__m128i*)(sa + 8), e); _mm_storeu_si128((__m128i*)(sa + 12), g);
_mm_storeu_si128((__m128i*)(sb + 8), f); _mm_storeu_si128((__m128i*)(sb + 12), h);
// This could be vectorized, but it's only executed every 5552*16 iterations.
uint64_t vs1 = 0;
for (uint32_t i = 0; i < 16; i++)
vs1 += sa[i];
uint64_t vs2_a = 0;
for (uint32_t i = 0; i < 16; i++)
vs2_a += sa[i] * (uint64_t)i;
uint64_t vs2_b = 0;
for (uint32_t i = 0; i < 16; i++)
vs2_b += sb[i];
vs2_b *= 16U;
uint64_t vs2 = vs2_b - vs2_a + s2;
s1 = (uint32_t)(vs1 % K);
s2 = (uint32_t)(vs2 % K);
p += n * 16;
len -= n * 16;
}
for (; len; len--)
{
s1 += *p++;
s2 += s1;
}
return (s1 % K) | ((s2 % K) << 16);
}
#endif
static uint32_t fpng_adler32_scalar(const uint8_t* ptr, size_t buf_len, uint32_t adler)
{
uint32_t i, s1 = (uint32_t)(adler & 0xffff), s2 = (uint32_t)(adler >> 16); uint32_t block_len = (uint32_t)(buf_len % 5552);
if (!ptr) return FPNG_ADLER32_INIT;
while (buf_len) {
for (i = 0; i + 7 < block_len; i += 8, ptr += 8) {
s1 += ptr[0], s2 += s1; s1 += ptr[1], s2 += s1; s1 += ptr[2], s2 += s1; s1 += ptr[3], s2 += s1;
s1 += ptr[4], s2 += s1; s1 += ptr[5], s2 += s1; s1 += ptr[6], s2 += s1; s1 += ptr[7], s2 += s1;
}
for (; i < block_len; ++i) s1 += *ptr++, s2 += s1;
s1 %= 65521U, s2 %= 65521U; buf_len -= block_len; block_len = 5552;
}
return (s2 << 16) + s1;
}
uint32_t fpng_adler32(const void* pData, size_t size, uint32_t adler)
{
#if FPNG_X86_OR_X64_CPU && !FPNG_NO_SSE
if (g_cpu_info.can_use_sse41())
return adler32_sse_16((const uint8_t*)pData, size, adler);
#endif
return fpng_adler32_scalar((const uint8_t*)pData, size, adler);
}
// Ensure we've been configured for endianness correctly.
static inline bool endian_check()
{
uint32_t endian_check = 0;
WRITE_LE32(&endian_check, 0x1234ABCD);
const uint32_t first_byte = reinterpret_cast<const uint8_t*>(&endian_check)[0];
return first_byte == 0xCD;
}
static const uint16_t g_defl_len_sym[256] = {
257,258,259,260,261,262,263,264,265,265,266,266,267,267,268,268,269,269,269,269,270,270,270,270,271,271,271,271,272,272,272,272,
273,273,273,273,273,273,273,273,274,274,274,274,274,274,274,274,275,275,275,275,275,275,275,275,276,276,276,276,276,276,276,276,
277,277,277,277,277,277,277,277,277,277,277,277,277,277,277,277,278,278,278,278,278,278,278,278,278,278,278,278,278,278,278,278,
279,279,279,279,279,279,279,279,279,279,279,279,279,279,279,279,280,280,280,280,280,280,280,280,280,280,280,280,280,280,280,280,
281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,281,
282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,282,
283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,283,
284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,284,285 };
static const uint8_t g_defl_len_extra[256] = {
0,0,0,0,0,0,0,0,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,
4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,4,
5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,0 };
static const uint8_t g_defl_small_dist_sym[512] = {
0,1,2,3,4,4,5,5,6,6,6,6,7,7,7,7,8,8,8,8,8,8,8,8,9,9,9,9,9,9,9,9,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,10,11,11,11,11,11,11,
11,11,11,11,11,11,11,11,11,11,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,12,13,
13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,13,14,14,14,14,14,14,14,14,14,14,14,14,
14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,14,
14,14,14,14,14,14,14,14,14,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,
15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,16,16,16,16,16,16,16,16,16,16,16,16,16,
16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,
16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,
16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,16,17,17,17,17,17,17,17,17,17,17,17,17,17,17,
17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,
17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,
17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17,17 };
static const uint32_t g_bitmasks[17] = { 0x0000, 0x0001, 0x0003, 0x0007, 0x000F, 0x001F, 0x003F, 0x007F, 0x00FF, 0x01FF, 0x03FF, 0x07FF, 0x0FFF, 0x1FFF, 0x3FFF, 0x7FFF, 0xFFFF };
// Huffman tables generated by fpng_test -t @filelist.txt. Total alpha files : 1440, Total opaque files : 5627.
// Feel free to retrain the encoder on your opaque/alpha PNG files by setting FPNG_TRAIN_HUFFMAN_TABLES and running fpng_test with the -t option.
static const uint8_t g_dyn_huff_3[] = {
120, 1, 237, 195, 3, 176, 110, 89, 122, 128, 225, 247, 251, 214, 218, 248, 113, 124, 173, 190, 109, 12, 50, 201, 196, 182, 109, 219, 182, 109, 219, 182,
109, 219, 201, 36, 147, 153, 105, 235, 246, 53, 142, 207, 143, 141, 181, 214, 151, 93, 117, 170, 78, 117, 117, 58, 206, 77, 210, 217, 169, 122 };
const uint32_t DYN_HUFF_3_BITBUF = 30, DYN_HUFF_3_BITBUF_SIZE = 7;
static const struct { uint8_t m_code_size; uint16_t m_code; } g_dyn_huff_3_codes[288] = {
{2,0},{4,2},{4,10},{5,14},{5,30},{6,25},{6,57},{6,5},{6,37},{7,3},{7,67},{7,35},{7,99},{8,11},{8,139},{8,75},{8,203},{8,43},{8,171},{8,107},{9,135},{9,391},{9,71},{9,327},{9,199},{9,455},{9,39},{9,295},{9,167},{9,423},{9,103},{10,183},
{9,359},{10,695},{10,439},{10,951},{10,119},{10,631},{10,375},{10,887},{10,247},{10,759},{10,503},{11,975},{11,1999},{11,47},{11,1071},{12,1199},{11,559},{12,3247},{12,687},{11,1583},{12,2735},{12,1711},{12,3759},{12,431},{12,2479},{12,1455},{12,3503},{12,943},{12,2991},{12,1967},{12,4015},{12,111},
{12,2159},{12,1135},{12,3183},{12,623},{12,2671},{12,1647},{12,3695},{12,367},{12,2415},{12,1391},{12,3439},{12,879},{12,2927},{12,1903},{12,3951},{12,239},{12,2287},{12,1263},{12,3311},{12,751},{12,2799},{12,1775},{12,3823},{12,495},{12,2543},{12,1519},{12,3567},{12,1007},{12,3055},{12,2031},{12,4079},{12,31},
{12,2079},{12,1055},{12,3103},{12,543},{12,2591},{12,1567},{12,3615},{12,287},{12,2335},{12,1311},{12,3359},{12,799},{12,2847},{12,1823},{12,3871},{12,159},{12,2207},{12,1183},{12,3231},{12,671},{12,2719},{12,1695},{12,3743},{12,415},{12,2463},{12,1439},{12,3487},{12,927},{12,2975},{12,1951},{12,3999},{12,95},
{12,2143},{12,1119},{12,3167},{12,607},{12,2655},{12,1631},{12,3679},{12,351},{12,2399},{12,1375},{12,3423},{12,863},{12,2911},{12,1887},{12,3935},{12,223},{12,2271},{12,1247},{12,3295},{12,735},{12,2783},{12,1759},{12,3807},{12,479},{12,2527},{12,1503},{12,3551},{12,991},{12,3039},{12,2015},{12,4063},{12,63},
{12,2111},{12,1087},{12,3135},{12,575},{12,2623},{12,1599},{12,3647},{12,319},{12,2367},{12,1343},{12,3391},{12,831},{12,2879},{12,1855},{12,3903},{12,191},{12,2239},{12,1215},{12,3263},{12,703},{12,2751},{12,1727},{12,3775},{12,447},{12,2495},{12,1471},{12,3519},{12,959},{12,3007},{12,1983},{12,4031},{12,127},
{12,2175},{12,1151},{12,3199},{12,639},{12,2687},{12,1663},{12,3711},{12,383},{12,2431},{12,1407},{12,3455},{12,895},{12,2943},{11,303},{12,1919},{12,3967},{11,1327},{12,255},{11,815},{11,1839},{11,175},{10,1015},{10,15},{10,527},{10,271},{10,783},{10,143},{10,655},{10,399},{10,911},{10,79},{10,591},
{9,231},{10,335},{9,487},{9,23},{9,279},{9,151},{9,407},{9,87},{9,343},{9,215},{9,471},{9,55},{8,235},{8,27},{8,155},{8,91},{8,219},{8,59},{8,187},{8,123},{7,19},{7,83},{7,51},{7,115},{6,21},{6,53},{6,13},{6,45},{5,1},{5,17},{5,9},{4,6},
{12,2303},{6,29},{0,0},{0,0},{8,251},{0,0},{0,0},{8,7},{0,0},{10,847},{0,0},{10,207},{12,1279},{10,719},{12,3327},{12,767},{12,2815},{12,1791},{12,3839},{12,511},{12,2559},{12,1535},{9,311},{12,3583},{12,1023},{12,3071},{10,463},{12,2047},{6,61},{12,4095},{0,0},{0,0}
};
static const uint8_t g_dyn_huff_4[] = {
120, 1, 229, 196, 99, 180, 37, 103, 218, 128, 225, 251, 121, 171, 106, 243, 216, 231, 180, 109, 196, 182, 51, 51, 73, 6, 201, 216, 182, 109, 219, 182,
17, 140, 98, 219, 102, 219, 60, 125, 172, 205, 170, 122, 159, 111, 213, 143, 179, 214, 94, 189, 58, 153, 104, 166, 103, 190, 247, 199, 117 };
const uint32_t DYN_HUFF_4_BITBUF = 1, DYN_HUFF_4_BITBUF_SIZE = 2;
static const struct { uint8_t m_code_size; uint16_t m_code; } g_dyn_huff_4_codes[288] = {
{2,0},{4,2},{5,6},{6,30},{6,62},{6,1},{7,41},{7,105},{7,25},{7,89},{7,57},{7,121},{8,117},{8,245},{8,13},{8,141},{8,77},{8,205},{8,45},{8,173},{8,109},{8,237},{8,29},{8,157},{8,93},{8,221},{8,61},{9,83},{9,339},{9,211},{9,467},{9,51},
{9,307},{9,179},{9,435},{9,115},{9,371},{9,243},{9,499},{9,11},{9,267},{9,139},{9,395},{9,75},{9,331},{9,203},{9,459},{9,43},{9,299},{10,7},{10,519},{10,263},{10,775},{10,135},{10,647},{10,391},{10,903},{10,71},{10,583},{10,327},{10,839},{10,199},{10,711},{10,455},
{10,967},{10,39},{10,551},{10,295},{10,807},{10,167},{10,679},{10,423},{10,935},{10,103},{10,615},{11,463},{11,1487},{11,975},{10,359},{10,871},{10,231},{11,1999},{11,47},{11,1071},{11,559},{10,743},{10,487},{11,1583},{11,303},{11,1327},{11,815},{11,1839},{11,175},{11,1199},{11,687},{11,1711},
{11,431},{11,1455},{11,943},{11,1967},{11,111},{11,1135},{11,623},{11,1647},{11,367},{11,1391},{11,879},{11,1903},{11,239},{11,1263},{11,751},{11,1775},{11,495},{11,1519},{11,1007},{11,2031},{11,31},{11,1055},{11,543},{11,1567},{11,287},{11,1311},{11,799},{11,1823},{11,159},{11,1183},{11,671},{11,1695},
{11,415},{11,1439},{11,927},{11,1951},{11,95},{11,1119},{11,607},{11,1631},{11,351},{11,1375},{11,863},{11,1887},{11,223},{11,1247},{11,735},{11,1759},{11,479},{11,1503},{11,991},{11,2015},{11,63},{11,1087},{11,575},{11,1599},{11,319},{11,1343},{11,831},{11,1855},{11,191},{11,1215},{11,703},{11,1727},
{11,447},{11,1471},{11,959},{11,1983},{11,127},{11,1151},{11,639},{11,1663},{11,383},{10,999},{10,23},{10,535},{10,279},{11,1407},{11,895},{11,1919},{11,255},{11,1279},{10,791},{10,151},{10,663},{10,407},{10,919},{10,87},{10,599},{10,343},{10,855},{10,215},{10,727},{10,471},{10,983},{10,55},
{10,567},{10,311},{10,823},{10,183},{10,695},{10,439},{10,951},{10,119},{10,631},{10,375},{10,887},{10,247},{10,759},{10,503},{10,1015},{10,15},{10,527},{10,271},{10,783},{10,143},{10,655},{10,399},{9,171},{9,427},{9,107},{9,363},{9,235},{9,491},{9,27},{9,283},{9,155},{9,411},
{9,91},{9,347},{9,219},{9,475},{9,59},{9,315},{9,187},{9,443},{8,189},{9,123},{8,125},{8,253},{8,3},{8,131},{8,67},{8,195},{8,35},{8,163},{8,99},{8,227},{8,19},{7,5},{7,69},{7,37},{7,101},{7,21},{7,85},{6,33},{6,17},{6,49},{5,22},{4,10},
{12,2047},{0,0},{6,9},{0,0},{0,0},{0,0},{8,147},{0,0},{0,0},{7,53},{0,0},{9,379},{0,0},{9,251},{10,911},{10,79},{11,767},{10,591},{10,335},{10,847},{10,207},{10,719},{11,1791},{11,511},{9,507},{11,1535},{11,1023},{12,4095},{5,14},{0,0},{0,0},{0,0}
};
#define PUT_BITS(bb, ll) do { uint32_t b = bb, l = ll; assert((l) >= 0 && (l) <= 16); assert((b) < (1ULL << (l))); bit_buf |= (((uint64_t)(b)) << bit_buf_size); bit_buf_size += (l); assert(bit_buf_size <= 64); } while(0)
#define PUT_BITS_CZ(bb, ll) do { uint32_t b = bb, l = ll; assert((l) >= 1 && (l) <= 16); assert((b) < (1ULL << (l))); bit_buf |= (((uint64_t)(b)) << bit_buf_size); bit_buf_size += (l); assert(bit_buf_size <= 64); } while(0)
#define PUT_BITS_FLUSH do { \
if ((dst_ofs + 8) > dst_buf_size) \
return 0; \
WRITE_LE64(pDst + dst_ofs, bit_buf); \
uint32_t bits_to_shift = bit_buf_size & ~7; \
dst_ofs += (bits_to_shift >> 3); \
assert(bits_to_shift < 64); \
bit_buf = bit_buf >> bits_to_shift; \
bit_buf_size -= bits_to_shift; \
} while(0)
#define PUT_BITS_FORCE_FLUSH do { \
while (bit_buf_size > 0) \
{ \
if ((dst_ofs + 1) > dst_buf_size) \
return 0; \
*(uint8_t*)(pDst + dst_ofs) = (uint8_t)bit_buf; \
dst_ofs++; \
bit_buf >>= 8; \
bit_buf_size -= 8; \
} \
} while(0)
enum
{
DEFL_MAX_HUFF_TABLES = 3,
DEFL_MAX_HUFF_SYMBOLS = 288,
DEFL_MAX_HUFF_SYMBOLS_0 = 288,
DEFL_MAX_HUFF_SYMBOLS_1 = 32,
DEFL_MAX_HUFF_SYMBOLS_2 = 19,
DEFL_LZ_DICT_SIZE = 32768,
DEFL_LZ_DICT_SIZE_MASK = DEFL_LZ_DICT_SIZE - 1,
DEFL_MIN_MATCH_LEN = 3,
DEFL_MAX_MATCH_LEN = 258
};
#if FPNG_TRAIN_HUFFMAN_TABLES
uint64_t g_huff_counts[HUFF_COUNTS_SIZE];
#endif
struct defl_huff
{
uint16_t m_huff_count[DEFL_MAX_HUFF_TABLES][DEFL_MAX_HUFF_SYMBOLS];
uint16_t m_huff_codes[DEFL_MAX_HUFF_TABLES][DEFL_MAX_HUFF_SYMBOLS];
uint8_t m_huff_code_sizes[DEFL_MAX_HUFF_TABLES][DEFL_MAX_HUFF_SYMBOLS];
};
struct defl_sym_freq
{
uint16_t m_key;
uint16_t m_sym_index;
};
#define DEFL_CLEAR_OBJ(obj) memset(&(obj), 0, sizeof(obj))
static defl_sym_freq* defl_radix_sort_syms(uint32_t num_syms, defl_sym_freq* pSyms0, defl_sym_freq* pSyms1)
{
uint32_t total_passes = 2, pass_shift, pass, i, hist[256 * 2]; defl_sym_freq* pCur_syms = pSyms0, * pNew_syms = pSyms1; DEFL_CLEAR_OBJ(hist);
for (i = 0; i < num_syms; i++) { uint32_t freq = pSyms0[i].m_key; hist[freq & 0xFF]++; hist[256 + ((freq >> 8) & 0xFF)]++; }
while ((total_passes > 1) && (num_syms == hist[(total_passes - 1) * 256])) total_passes--;
for (pass_shift = 0, pass = 0; pass < total_passes; pass++, pass_shift += 8)
{
const uint32_t* pHist = &hist[pass << 8];
uint32_t offsets[256], cur_ofs = 0;
for (i = 0; i < 256; i++) { offsets[i] = cur_ofs; cur_ofs += pHist[i]; }
for (i = 0; i < num_syms; i++) pNew_syms[offsets[(pCur_syms[i].m_key >> pass_shift) & 0xFF]++] = pCur_syms[i];
{ defl_sym_freq* t = pCur_syms; pCur_syms = pNew_syms; pNew_syms = t; }
}
return pCur_syms;
}
// defl_calculate_minimum_redundancy() originally written by: Alistair Moffat, [email protected], Jyrki Katajainen, [email protected], November 1996.
static void defl_calculate_minimum_redundancy(defl_sym_freq* A, int n)
{
int root, leaf, next, avbl, used, dpth;
if (n == 0) return; else if (n == 1) { A[0].m_key = 1; return; }
A[0].m_key += A[1].m_key; root = 0; leaf = 2;
for (next = 1; next < n - 1; next++)
{
if (leaf >= n || A[root].m_key < A[leaf].m_key) { A[next].m_key = A[root].m_key; A[root++].m_key = (uint16_t)next; }
else A[next].m_key = A[leaf++].m_key;
if (leaf >= n || (root < next && A[root].m_key < A[leaf].m_key)) { A[next].m_key = (uint16_t)(A[next].m_key + A[root].m_key); A[root++].m_key = (uint16_t)next; }
else A[next].m_key = (uint16_t)(A[next].m_key + A[leaf++].m_key);
}
A[n - 2].m_key = 0; for (next = n - 3; next >= 0; next--) A[next].m_key = A[A[next].m_key].m_key + 1;
avbl = 1; used = dpth = 0; root = n - 2; next = n - 1;
while (avbl > 0)
{
while (root >= 0 && (int)A[root].m_key == dpth) { used++; root--; }
while (avbl > used) { A[next--].m_key = (uint16_t)(dpth); avbl--; }
avbl = 2 * used; dpth++; used = 0;
}
}
// Limits canonical Huffman code table's max code size.
enum { DEFL_MAX_SUPPORTED_HUFF_CODESIZE = 32 };
static void defl_huffman_enforce_max_code_size(int* pNum_codes, int code_list_len, int max_code_size)
{
int i; uint32_t total = 0; if (code_list_len <= 1) return;
for (i = max_code_size + 1; i <= DEFL_MAX_SUPPORTED_HUFF_CODESIZE; i++) pNum_codes[max_code_size] += pNum_codes[i];
for (i = max_code_size; i > 0; i--) total += (((uint32_t)pNum_codes[i]) << (max_code_size - i));
while (total != (1UL << max_code_size))
{
pNum_codes[max_code_size]--;
for (i = max_code_size - 1; i > 0; i--) if (pNum_codes[i]) { pNum_codes[i]--; pNum_codes[i + 1] += 2; break; }
total--;
}
}
static void defl_optimize_huffman_table(defl_huff* d, int table_num, int table_len, int code_size_limit, int static_table)
{
int i, j, l, num_codes[1 + DEFL_MAX_SUPPORTED_HUFF_CODESIZE]; uint32_t next_code[DEFL_MAX_SUPPORTED_HUFF_CODESIZE + 1]; DEFL_CLEAR_OBJ(num_codes);
if (static_table)
{
for (i = 0; i < table_len; i++) num_codes[d->m_huff_code_sizes[table_num][i]]++;
}
else
{
defl_sym_freq syms0[DEFL_MAX_HUFF_SYMBOLS], syms1[DEFL_MAX_HUFF_SYMBOLS], * pSyms;
int num_used_syms = 0;
const uint16_t* pSym_count = &d->m_huff_count[table_num][0];
for (i = 0; i < table_len; i++) if (pSym_count[i]) { syms0[num_used_syms].m_key = (uint16_t)pSym_count[i]; syms0[num_used_syms++].m_sym_index = (uint16_t)i; }
pSyms = defl_radix_sort_syms(num_used_syms, syms0, syms1); defl_calculate_minimum_redundancy(pSyms, num_used_syms);
for (i = 0; i < num_used_syms; i++) num_codes[pSyms[i].m_key]++;
defl_huffman_enforce_max_code_size(num_codes, num_used_syms, code_size_limit);
DEFL_CLEAR_OBJ(d->m_huff_code_sizes[table_num]); DEFL_CLEAR_OBJ(d->m_huff_codes[table_num]);
for (i = 1, j = num_used_syms; i <= code_size_limit; i++)
for (l = num_codes[i]; l > 0; l--) d->m_huff_code_sizes[table_num][pSyms[--j].m_sym_index] = (uint8_t)(i);
}
next_code[1] = 0; for (j = 0, i = 2; i <= code_size_limit; i++) next_code[i] = j = ((j + num_codes[i - 1]) << 1);
for (i = 0; i < table_len; i++)
{
uint32_t rev_code = 0, code, code_size; if ((code_size = d->m_huff_code_sizes[table_num][i]) == 0) continue;
code = next_code[code_size]++; for (l = code_size; l > 0; l--, code >>= 1) rev_code = (rev_code << 1) | (code & 1);
d->m_huff_codes[table_num][i] = (uint16_t)rev_code;
}
}
#define DEFL_RLE_PREV_CODE_SIZE() { if (rle_repeat_count) { \
if (rle_repeat_count < 3) { \
d->m_huff_count[2][prev_code_size] = (uint16_t)(d->m_huff_count[2][prev_code_size] + rle_repeat_count); \
while (rle_repeat_count--) packed_code_sizes[num_packed_code_sizes++] = prev_code_size; \
} else { \
d->m_huff_count[2][16] = (uint16_t)(d->m_huff_count[2][16] + 1); packed_code_sizes[num_packed_code_sizes++] = 16; packed_code_sizes[num_packed_code_sizes++] = (uint8_t)(rle_repeat_count - 3); \
} rle_repeat_count = 0; } }
#define DEFL_RLE_ZERO_CODE_SIZE() { if (rle_z_count) { \
if (rle_z_count < 3) { \
d->m_huff_count[2][0] = (uint16_t)(d->m_huff_count[2][0] + rle_z_count); while (rle_z_count--) packed_code_sizes[num_packed_code_sizes++] = 0; \
} else if (rle_z_count <= 10) { \
d->m_huff_count[2][17] = (uint16_t)(d->m_huff_count[2][17] + 1); packed_code_sizes[num_packed_code_sizes++] = 17; packed_code_sizes[num_packed_code_sizes++] = (uint8_t)(rle_z_count - 3); \
} else { \
d->m_huff_count[2][18] = (uint16_t)(d->m_huff_count[2][18] + 1); packed_code_sizes[num_packed_code_sizes++] = 18; packed_code_sizes[num_packed_code_sizes++] = (uint8_t)(rle_z_count - 11); \
} rle_z_count = 0; } }
static uint8_t g_defl_packed_code_size_syms_swizzle[] = { 16, 17, 18, 0, 8, 7, 9, 6, 10, 5, 11, 4, 12, 3, 13, 2, 14, 1, 15 };
#define DEFL_DYN_PUT_BITS(bb, ll) \
do { \
uint32_t b = (bb), l = (ll); \
assert((l) >= 1 && (l) <= 16); assert((b) < (1ULL << (l))); \
bit_buf |= (((uint64_t)(b)) << bit_buf_size); bit_buf_size += (l); assert(bit_buf_size <= 64); \
while (bit_buf_size >= 8) \
{ \
if ((dst_ofs + 1) > dst_buf_size) \
return false; \
*(uint8_t*)(pDst + dst_ofs) = (uint8_t)bit_buf; \
dst_ofs++; \
bit_buf >>= 8; \
bit_buf_size -= 8; \
} \
} while(0)
static bool defl_start_dynamic_block(defl_huff* d, uint8_t* pDst, uint32_t& dst_ofs, uint32_t dst_buf_size, uint64_t& bit_buf, int& bit_buf_size)
{
int num_lit_codes, num_dist_codes, num_bit_lengths; uint32_t i, total_code_sizes_to_pack, num_packed_code_sizes, rle_z_count, rle_repeat_count, packed_code_sizes_index;
uint8_t code_sizes_to_pack[DEFL_MAX_HUFF_SYMBOLS_0 + DEFL_MAX_HUFF_SYMBOLS_1], packed_code_sizes[DEFL_MAX_HUFF_SYMBOLS_0 + DEFL_MAX_HUFF_SYMBOLS_1], prev_code_size = 0xFF;
#if FPNG_TRAIN_HUFFMAN_TABLES
assert(HUFF_COUNTS_SIZE == DEFL_MAX_HUFF_SYMBOLS_0);
for (uint32_t i = 0; i < DEFL_MAX_HUFF_SYMBOLS_0; i++)
g_huff_counts[i] += d->m_huff_count[0][i];
#endif
d->m_huff_count[0][256] = 1;
defl_optimize_huffman_table(d, 0, DEFL_MAX_HUFF_SYMBOLS_0, 12, FPNG_FALSE);
defl_optimize_huffman_table(d, 1, DEFL_MAX_HUFF_SYMBOLS_1, 12, FPNG_FALSE);
for (num_lit_codes = 286; num_lit_codes > 257; num_lit_codes--) if (d->m_huff_code_sizes[0][num_lit_codes - 1]) break;
for (num_dist_codes = 30; num_dist_codes > 1; num_dist_codes--) if (d->m_huff_code_sizes[1][num_dist_codes - 1]) break;
memcpy(code_sizes_to_pack, &d->m_huff_code_sizes[0][0], num_lit_codes);
memcpy(code_sizes_to_pack + num_lit_codes, &d->m_huff_code_sizes[1][0], num_dist_codes);
total_code_sizes_to_pack = num_lit_codes + num_dist_codes; num_packed_code_sizes = 0; rle_z_count = 0; rle_repeat_count = 0;
memset(&d->m_huff_count[2][0], 0, sizeof(d->m_huff_count[2][0]) * DEFL_MAX_HUFF_SYMBOLS_2);
for (i = 0; i < total_code_sizes_to_pack; i++)
{
uint8_t code_size = code_sizes_to_pack[i];
if (!code_size)
{
DEFL_RLE_PREV_CODE_SIZE();
if (++rle_z_count == 138) { DEFL_RLE_ZERO_CODE_SIZE(); }
}
else
{
DEFL_RLE_ZERO_CODE_SIZE();
if (code_size != prev_code_size)
{
DEFL_RLE_PREV_CODE_SIZE();
d->m_huff_count[2][code_size] = (uint16_t)(d->m_huff_count[2][code_size] + 1); packed_code_sizes[num_packed_code_sizes++] = code_size;
}
else if (++rle_repeat_count == 6)
{
DEFL_RLE_PREV_CODE_SIZE();
}
}
prev_code_size = code_size;
}
if (rle_repeat_count) { DEFL_RLE_PREV_CODE_SIZE(); }
else { DEFL_RLE_ZERO_CODE_SIZE(); }
defl_optimize_huffman_table(d, 2, DEFL_MAX_HUFF_SYMBOLS_2, 7, FPNG_FALSE);
// max of 2+5+5+4+18*3+(288+32)*7=2310 bits
DEFL_DYN_PUT_BITS(2, 2);
DEFL_DYN_PUT_BITS(num_lit_codes - 257, 5);
DEFL_DYN_PUT_BITS(num_dist_codes - 1, 5);
for (num_bit_lengths = 18; num_bit_lengths >= 0; num_bit_lengths--) if (d->m_huff_code_sizes[2][g_defl_packed_code_size_syms_swizzle[num_bit_lengths]]) break;
num_bit_lengths = maximum<int>(4, (num_bit_lengths + 1)); DEFL_DYN_PUT_BITS(num_bit_lengths - 4, 4);
for (i = 0; (int)i < num_bit_lengths; i++) DEFL_DYN_PUT_BITS(d->m_huff_code_sizes[2][g_defl_packed_code_size_syms_swizzle[i]], 3);
for (packed_code_sizes_index = 0; packed_code_sizes_index < num_packed_code_sizes; )
{
uint32_t code = packed_code_sizes[packed_code_sizes_index++]; assert(code < DEFL_MAX_HUFF_SYMBOLS_2);
DEFL_DYN_PUT_BITS(d->m_huff_codes[2][code], d->m_huff_code_sizes[2][code]);
if (code >= 16) DEFL_DYN_PUT_BITS(packed_code_sizes[packed_code_sizes_index++], "\02\03\07"[code - 16]);
}
return true;
}
static uint32_t write_raw_block(const uint8_t* pSrc, uint32_t src_len, uint8_t* pDst, uint32_t dst_buf_size)
{
if (dst_buf_size < 2)
return 0;
pDst[0] = 0x78;
pDst[1] = 0x01;
uint32_t dst_ofs = 2;
uint32_t src_ofs = 0;
while (src_ofs < src_len)
{
const uint32_t src_remaining = src_len - src_ofs;
const uint32_t block_size = minimum<uint32_t>(UINT16_MAX, src_remaining);
const bool final_block = (block_size == src_remaining);
if ((dst_ofs + 5 + block_size) > dst_buf_size)
return 0;
pDst[dst_ofs + 0] = final_block ? 1 : 0;
pDst[dst_ofs + 1] = block_size & 0xFF;
pDst[dst_ofs + 2] = (block_size >> 8) & 0xFF;
pDst[dst_ofs + 3] = (~block_size) & 0xFF;
pDst[dst_ofs + 4] = ((~block_size) >> 8) & 0xFF;
memcpy(pDst + dst_ofs + 5, pSrc + src_ofs, block_size);
src_ofs += block_size;
dst_ofs += 5 + block_size;
}
uint32_t src_adler32 = fpng_adler32(pSrc, src_len, FPNG_ADLER32_INIT);
for (uint32_t i = 0; i < 4; i++)
{
if (dst_ofs + 1 > dst_buf_size)
return 0;
pDst[dst_ofs] = (uint8_t)(src_adler32 >> 24);
dst_ofs++;
src_adler32 <<= 8;
}
return dst_ofs;
}
static void adjust_freq32(uint32_t num_freq, uint32_t* pFreq, uint16_t* pFreq16)
{
uint32_t total_freq = 0;
for (uint32_t i = 0; i < num_freq; i++)
total_freq += pFreq[i];
if (!total_freq)
{
memset(pFreq16, 0, num_freq * sizeof(uint16_t));
return;
}
uint32_t total_freq16 = 0;
for (uint32_t i = 0; i < num_freq; i++)
{
uint64_t f = pFreq[i];
if (!f)
{
pFreq16[i] = 0;
continue;
}
pFreq16[i] = (uint16_t)maximum<uint32_t>(1, (uint32_t)((f * UINT16_MAX) / total_freq));
total_freq16 += pFreq16[i];
}
while (total_freq16 > UINT16_MAX)
{
total_freq16 = 0;
for (uint32_t i = 0; i < num_freq; i++)
{
if (pFreq[i])
{
pFreq[i] = maximum<uint32_t>(1, pFreq[i] >> 1);
total_freq16 += pFreq[i];
}
}
}
}
#if FPNG_TRAIN_HUFFMAN_TABLES
bool create_dynamic_block_prefix(uint64_t* pFreq, uint32_t num_chans, std::vector<uint8_t>& prefix, uint64_t& bit_buf, int &bit_buf_size, uint32_t* pCodes, uint8_t* pCodesizes)
{
assert((num_chans == 3) || (num_chans == 4));
assert(HUFF_COUNTS_SIZE == DEFL_MAX_HUFF_SYMBOLS_0); // must be equal
defl_huff dh;
memset(&dh, 0, sizeof(dh));
uint32_t lit_freq[DEFL_MAX_HUFF_SYMBOLS_0];
uint32_t shift_len = 0;
for (; ; )
{
uint32_t i;
for (i = 0; i < DEFL_MAX_HUFF_SYMBOLS_0; i++)
{
uint64_t f = pFreq[i];
if (f)
f = maximum<uint64_t>(1U, f >> shift_len);
if (f > UINT32_MAX)
break;
lit_freq[i] = (uint32_t)pFreq[i];
}
if (i == DEFL_MAX_HUFF_SYMBOLS_0)
break;
shift_len++;
}
// Ensure all valid Deflate literal/EOB/length syms are non-zero, so anything can be coded.
for (uint32_t i = 0; i <= 256; i++)
{
if (!lit_freq[i])
lit_freq[i] = 1;
}
for (uint32_t len = num_chans; len <= DEFL_MAX_MATCH_LEN; len += num_chans)
{
uint32_t sym = g_defl_len_sym[len - 3];
if (!lit_freq[sym])
lit_freq[sym] = 1;
}
adjust_freq32(DEFL_MAX_HUFF_SYMBOLS_0, lit_freq, &dh.m_huff_count[0][0]);
const uint32_t dist_sym = g_defl_small_dist_sym[num_chans - 1];
dh.m_huff_count[1][dist_sym] = 1;
dh.m_huff_count[1][dist_sym + 1] = 1; // to workaround a bug in wuffs decoder
prefix.resize(4096);
uint8_t* pDst = prefix.data();
uint32_t dst_buf_size = (uint32_t)prefix.size();
uint32_t dst_ofs = 0;
// zlib header
PUT_BITS(0x78, 8);
PUT_BITS(0x01, 8);
// write BFINAL bit
PUT_BITS(1, 1);
if (!defl_start_dynamic_block(&dh, pDst, dst_ofs, dst_buf_size, bit_buf, bit_buf_size))
return false;
prefix.resize(dst_ofs);
for (uint32_t i = 0; i < DEFL_MAX_HUFF_SYMBOLS_0; i++)
{
pCodes[i] = dh.m_huff_codes[0][i];
pCodesizes[i] = dh.m_huff_code_sizes[0][i];
}
return true;
}
#endif