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-rw-r--r--src/3rdparty/libwebp/src/dsp/lossless.c1532
1 files changed, 1532 insertions, 0 deletions
diff --git a/src/3rdparty/libwebp/src/dsp/lossless.c b/src/3rdparty/libwebp/src/dsp/lossless.c
new file mode 100644
index 0000000..bab76d2
--- /dev/null
+++ b/src/3rdparty/libwebp/src/dsp/lossless.c
@@ -0,0 +1,1532 @@
+// Copyright 2012 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// Image transforms and color space conversion methods for lossless decoder.
+//
+// Authors: Vikas Arora (vikaas.arora@gmail.com)
+// Jyrki Alakuijala (jyrki@google.com)
+// Urvang Joshi (urvang@google.com)
+
+#include "./dsp.h"
+
+#if defined(WEBP_USE_SSE2)
+#include <emmintrin.h>
+#endif
+
+#include <math.h>
+#include <stdlib.h>
+#include "./lossless.h"
+#include "../dec/vp8li.h"
+#include "./yuv.h"
+
+#define MAX_DIFF_COST (1e30f)
+
+// lookup table for small values of log2(int)
+#define APPROX_LOG_MAX 4096
+#define LOG_2_RECIPROCAL 1.44269504088896338700465094007086
+const float kLog2Table[LOG_LOOKUP_IDX_MAX] = {
+ 0.0000000000000000f, 0.0000000000000000f,
+ 1.0000000000000000f, 1.5849625007211560f,
+ 2.0000000000000000f, 2.3219280948873621f,
+ 2.5849625007211560f, 2.8073549220576041f,
+ 3.0000000000000000f, 3.1699250014423121f,
+ 3.3219280948873621f, 3.4594316186372973f,
+ 3.5849625007211560f, 3.7004397181410921f,
+ 3.8073549220576041f, 3.9068905956085187f,
+ 4.0000000000000000f, 4.0874628412503390f,
+ 4.1699250014423121f, 4.2479275134435852f,
+ 4.3219280948873626f, 4.3923174227787606f,
+ 4.4594316186372973f, 4.5235619560570130f,
+ 4.5849625007211560f, 4.6438561897747243f,
+ 4.7004397181410917f, 4.7548875021634682f,
+ 4.8073549220576037f, 4.8579809951275718f,
+ 4.9068905956085187f, 4.9541963103868749f,
+ 5.0000000000000000f, 5.0443941193584533f,
+ 5.0874628412503390f, 5.1292830169449663f,
+ 5.1699250014423121f, 5.2094533656289501f,
+ 5.2479275134435852f, 5.2854022188622487f,
+ 5.3219280948873626f, 5.3575520046180837f,
+ 5.3923174227787606f, 5.4262647547020979f,
+ 5.4594316186372973f, 5.4918530963296747f,
+ 5.5235619560570130f, 5.5545888516776376f,
+ 5.5849625007211560f, 5.6147098441152083f,
+ 5.6438561897747243f, 5.6724253419714951f,
+ 5.7004397181410917f, 5.7279204545631987f,
+ 5.7548875021634682f, 5.7813597135246599f,
+ 5.8073549220576037f, 5.8328900141647412f,
+ 5.8579809951275718f, 5.8826430493618415f,
+ 5.9068905956085187f, 5.9307373375628866f,
+ 5.9541963103868749f, 5.9772799234999167f,
+ 6.0000000000000000f, 6.0223678130284543f,
+ 6.0443941193584533f, 6.0660891904577720f,
+ 6.0874628412503390f, 6.1085244567781691f,
+ 6.1292830169449663f, 6.1497471195046822f,
+ 6.1699250014423121f, 6.1898245588800175f,
+ 6.2094533656289501f, 6.2288186904958804f,
+ 6.2479275134435852f, 6.2667865406949010f,
+ 6.2854022188622487f, 6.3037807481771030f,
+ 6.3219280948873626f, 6.3398500028846243f,
+ 6.3575520046180837f, 6.3750394313469245f,
+ 6.3923174227787606f, 6.4093909361377017f,
+ 6.4262647547020979f, 6.4429434958487279f,
+ 6.4594316186372973f, 6.4757334309663976f,
+ 6.4918530963296747f, 6.5077946401986963f,
+ 6.5235619560570130f, 6.5391588111080309f,
+ 6.5545888516776376f, 6.5698556083309478f,
+ 6.5849625007211560f, 6.5999128421871278f,
+ 6.6147098441152083f, 6.6293566200796094f,
+ 6.6438561897747243f, 6.6582114827517946f,
+ 6.6724253419714951f, 6.6865005271832185f,
+ 6.7004397181410917f, 6.7142455176661224f,
+ 6.7279204545631987f, 6.7414669864011464f,
+ 6.7548875021634682f, 6.7681843247769259f,
+ 6.7813597135246599f, 6.7944158663501061f,
+ 6.8073549220576037f, 6.8201789624151878f,
+ 6.8328900141647412f, 6.8454900509443747f,
+ 6.8579809951275718f, 6.8703647195834047f,
+ 6.8826430493618415f, 6.8948177633079437f,
+ 6.9068905956085187f, 6.9188632372745946f,
+ 6.9307373375628866f, 6.9425145053392398f,
+ 6.9541963103868749f, 6.9657842846620869f,
+ 6.9772799234999167f, 6.9886846867721654f,
+ 7.0000000000000000f, 7.0112272554232539f,
+ 7.0223678130284543f, 7.0334230015374501f,
+ 7.0443941193584533f, 7.0552824355011898f,
+ 7.0660891904577720f, 7.0768155970508308f,
+ 7.0874628412503390f, 7.0980320829605263f,
+ 7.1085244567781691f, 7.1189410727235076f,
+ 7.1292830169449663f, 7.1395513523987936f,
+ 7.1497471195046822f, 7.1598713367783890f,
+ 7.1699250014423121f, 7.1799090900149344f,
+ 7.1898245588800175f, 7.1996723448363644f,
+ 7.2094533656289501f, 7.2191685204621611f,
+ 7.2288186904958804f, 7.2384047393250785f,
+ 7.2479275134435852f, 7.2573878426926521f,
+ 7.2667865406949010f, 7.2761244052742375f,
+ 7.2854022188622487f, 7.2946207488916270f,
+ 7.3037807481771030f, 7.3128829552843557f,
+ 7.3219280948873626f, 7.3309168781146167f,
+ 7.3398500028846243f, 7.3487281542310771f,
+ 7.3575520046180837f, 7.3663222142458160f,
+ 7.3750394313469245f, 7.3837042924740519f,
+ 7.3923174227787606f, 7.4008794362821843f,
+ 7.4093909361377017f, 7.4178525148858982f,
+ 7.4262647547020979f, 7.4346282276367245f,
+ 7.4429434958487279f, 7.4512111118323289f,
+ 7.4594316186372973f, 7.4676055500829976f,
+ 7.4757334309663976f, 7.4838157772642563f,
+ 7.4918530963296747f, 7.4998458870832056f,
+ 7.5077946401986963f, 7.5156998382840427f,
+ 7.5235619560570130f, 7.5313814605163118f,
+ 7.5391588111080309f, 7.5468944598876364f,
+ 7.5545888516776376f, 7.5622424242210728f,
+ 7.5698556083309478f, 7.5774288280357486f,
+ 7.5849625007211560f, 7.5924570372680806f,
+ 7.5999128421871278f, 7.6073303137496104f,
+ 7.6147098441152083f, 7.6220518194563764f,
+ 7.6293566200796094f, 7.6366246205436487f,
+ 7.6438561897747243f, 7.6510516911789281f,
+ 7.6582114827517946f, 7.6653359171851764f,
+ 7.6724253419714951f, 7.6794800995054464f,
+ 7.6865005271832185f, 7.6934869574993252f,
+ 7.7004397181410917f, 7.7073591320808825f,
+ 7.7142455176661224f, 7.7210991887071855f,
+ 7.7279204545631987f, 7.7347096202258383f,
+ 7.7414669864011464f, 7.7481928495894605f,
+ 7.7548875021634682f, 7.7615512324444795f,
+ 7.7681843247769259f, 7.7747870596011736f,
+ 7.7813597135246599f, 7.7879025593914317f,
+ 7.7944158663501061f, 7.8008998999203047f,
+ 7.8073549220576037f, 7.8137811912170374f,
+ 7.8201789624151878f, 7.8265484872909150f,
+ 7.8328900141647412f, 7.8392037880969436f,
+ 7.8454900509443747f, 7.8517490414160571f,
+ 7.8579809951275718f, 7.8641861446542797f,
+ 7.8703647195834047f, 7.8765169465649993f,
+ 7.8826430493618415f, 7.8887432488982591f,
+ 7.8948177633079437f, 7.9008668079807486f,
+ 7.9068905956085187f, 7.9128893362299619f,
+ 7.9188632372745946f, 7.9248125036057812f,
+ 7.9307373375628866f, 7.9366379390025709f,
+ 7.9425145053392398f, 7.9483672315846778f,
+ 7.9541963103868749f, 7.9600019320680805f,
+ 7.9657842846620869f, 7.9715435539507719f,
+ 7.9772799234999167f, 7.9829935746943103f,
+ 7.9886846867721654f, 7.9943534368588577f
+};
+
+const float kSLog2Table[LOG_LOOKUP_IDX_MAX] = {
+ 0.00000000f, 0.00000000f, 2.00000000f, 4.75488750f,
+ 8.00000000f, 11.60964047f, 15.50977500f, 19.65148445f,
+ 24.00000000f, 28.52932501f, 33.21928095f, 38.05374781f,
+ 43.01955001f, 48.10571634f, 53.30296891f, 58.60335893f,
+ 64.00000000f, 69.48686830f, 75.05865003f, 80.71062276f,
+ 86.43856190f, 92.23866588f, 98.10749561f, 104.04192499f,
+ 110.03910002f, 116.09640474f, 122.21143267f, 128.38196256f,
+ 134.60593782f, 140.88144886f, 147.20671787f, 153.58008562f,
+ 160.00000000f, 166.46500594f, 172.97373660f, 179.52490559f,
+ 186.11730005f, 192.74977453f, 199.42124551f, 206.13068654f,
+ 212.87712380f, 219.65963219f, 226.47733176f, 233.32938445f,
+ 240.21499122f, 247.13338933f, 254.08384998f, 261.06567603f,
+ 268.07820003f, 275.12078236f, 282.19280949f, 289.29369244f,
+ 296.42286534f, 303.57978409f, 310.76392512f, 317.97478424f,
+ 325.21187564f, 332.47473081f, 339.76289772f, 347.07593991f,
+ 354.41343574f, 361.77497759f, 369.16017124f, 376.56863518f,
+ 384.00000000f, 391.45390785f, 398.93001188f, 406.42797576f,
+ 413.94747321f, 421.48818752f, 429.04981119f, 436.63204548f,
+ 444.23460010f, 451.85719280f, 459.49954906f, 467.16140179f,
+ 474.84249102f, 482.54256363f, 490.26137307f, 497.99867911f,
+ 505.75424759f, 513.52785023f, 521.31926438f, 529.12827280f,
+ 536.95466351f, 544.79822957f, 552.65876890f, 560.53608414f,
+ 568.42998244f, 576.34027536f, 584.26677867f, 592.20931226f,
+ 600.16769996f, 608.14176943f, 616.13135206f, 624.13628279f,
+ 632.15640007f, 640.19154569f, 648.24156472f, 656.30630539f,
+ 664.38561898f, 672.47935976f, 680.58738488f, 688.70955430f,
+ 696.84573069f, 704.99577935f, 713.15956818f, 721.33696754f,
+ 729.52785023f, 737.73209140f, 745.94956849f, 754.18016116f,
+ 762.42375127f, 770.68022275f, 778.94946161f, 787.23135586f,
+ 795.52579543f, 803.83267219f, 812.15187982f, 820.48331383f,
+ 828.82687147f, 837.18245171f, 845.54995518f, 853.92928416f,
+ 862.32034249f, 870.72303558f, 879.13727036f, 887.56295522f,
+ 896.00000000f, 904.44831595f, 912.90781569f, 921.37841320f,
+ 929.86002376f, 938.35256392f, 946.85595152f, 955.37010560f,
+ 963.89494641f, 972.43039537f, 980.97637504f, 989.53280911f,
+ 998.09962237f, 1006.67674069f, 1015.26409097f, 1023.86160116f,
+ 1032.46920021f, 1041.08681805f, 1049.71438560f, 1058.35183469f,
+ 1066.99909811f, 1075.65610955f, 1084.32280357f, 1092.99911564f,
+ 1101.68498204f, 1110.38033993f, 1119.08512727f, 1127.79928282f,
+ 1136.52274614f, 1145.25545758f, 1153.99735821f, 1162.74838989f,
+ 1171.50849518f, 1180.27761738f, 1189.05570047f, 1197.84268914f,
+ 1206.63852876f, 1215.44316535f, 1224.25654560f, 1233.07861684f,
+ 1241.90932703f, 1250.74862473f, 1259.59645914f, 1268.45278005f,
+ 1277.31753781f, 1286.19068338f, 1295.07216828f, 1303.96194457f,
+ 1312.85996488f, 1321.76618236f, 1330.68055071f, 1339.60302413f,
+ 1348.53355734f, 1357.47210556f, 1366.41862452f, 1375.37307041f,
+ 1384.33539991f, 1393.30557020f, 1402.28353887f, 1411.26926400f,
+ 1420.26270412f, 1429.26381818f, 1438.27256558f, 1447.28890615f,
+ 1456.31280014f, 1465.34420819f, 1474.38309138f, 1483.42941118f,
+ 1492.48312945f, 1501.54420843f, 1510.61261078f, 1519.68829949f,
+ 1528.77123795f, 1537.86138993f, 1546.95871952f, 1556.06319119f,
+ 1565.17476976f, 1574.29342040f, 1583.41910860f, 1592.55180020f,
+ 1601.69146137f, 1610.83805860f, 1619.99155871f, 1629.15192882f,
+ 1638.31913637f, 1647.49314911f, 1656.67393509f, 1665.86146266f,
+ 1675.05570047f, 1684.25661744f, 1693.46418280f, 1702.67836605f,
+ 1711.89913698f, 1721.12646563f, 1730.36032233f, 1739.60067768f,
+ 1748.84750254f, 1758.10076802f, 1767.36044551f, 1776.62650662f,
+ 1785.89892323f, 1795.17766747f, 1804.46271172f, 1813.75402857f,
+ 1823.05159087f, 1832.35537170f, 1841.66534438f, 1850.98148244f,
+ 1860.30375965f, 1869.63214999f, 1878.96662767f, 1888.30716711f,
+ 1897.65374295f, 1907.00633003f, 1916.36490342f, 1925.72943838f,
+ 1935.09991037f, 1944.47629506f, 1953.85856831f, 1963.24670620f,
+ 1972.64068498f, 1982.04048108f, 1991.44607117f, 2000.85743204f,
+ 2010.27454072f, 2019.69737440f, 2029.12591044f, 2038.56012640f
+};
+
+const VP8LPrefixCode kPrefixEncodeCode[PREFIX_LOOKUP_IDX_MAX] = {
+ { 0, 0}, { 0, 0}, { 1, 0}, { 2, 0}, { 3, 0}, { 4, 1}, { 4, 1}, { 5, 1},
+ { 5, 1}, { 6, 2}, { 6, 2}, { 6, 2}, { 6, 2}, { 7, 2}, { 7, 2}, { 7, 2},
+ { 7, 2}, { 8, 3}, { 8, 3}, { 8, 3}, { 8, 3}, { 8, 3}, { 8, 3}, { 8, 3},
+ { 8, 3}, { 9, 3}, { 9, 3}, { 9, 3}, { 9, 3}, { 9, 3}, { 9, 3}, { 9, 3},
+ { 9, 3}, {10, 4}, {10, 4}, {10, 4}, {10, 4}, {10, 4}, {10, 4}, {10, 4},
+ {10, 4}, {10, 4}, {10, 4}, {10, 4}, {10, 4}, {10, 4}, {10, 4}, {10, 4},
+ {10, 4}, {11, 4}, {11, 4}, {11, 4}, {11, 4}, {11, 4}, {11, 4}, {11, 4},
+ {11, 4}, {11, 4}, {11, 4}, {11, 4}, {11, 4}, {11, 4}, {11, 4}, {11, 4},
+ {11, 4}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5},
+ {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5},
+ {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5},
+ {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5}, {12, 5},
+ {12, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5},
+ {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5},
+ {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5},
+ {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5}, {13, 5},
+ {13, 5}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6},
+ {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6},
+ {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6},
+ {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6},
+ {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6},
+ {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6},
+ {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6},
+ {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6}, {14, 6},
+ {14, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6},
+ {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6},
+ {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6},
+ {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6},
+ {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6},
+ {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6},
+ {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6},
+ {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6}, {15, 6},
+ {15, 6}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7}, {16, 7},
+ {16, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+ {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7}, {17, 7},
+};
+
+const uint8_t kPrefixEncodeExtraBitsValue[PREFIX_LOOKUP_IDX_MAX] = {
+ 0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 1, 2, 3, 0, 1, 2, 3,
+ 0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 6, 7,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+ 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+ 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+ 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
+ 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
+ 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
+ 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
+ 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126,
+ 127,
+ 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+ 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31,
+ 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47,
+ 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63,
+ 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79,
+ 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,
+ 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111,
+ 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126
+};
+
+float VP8LFastSLog2Slow(int v) {
+ assert(v >= LOG_LOOKUP_IDX_MAX);
+ if (v < APPROX_LOG_MAX) {
+ int log_cnt = 0;
+ const float v_f = (float)v;
+ while (v >= LOG_LOOKUP_IDX_MAX) {
+ ++log_cnt;
+ v = v >> 1;
+ }
+ return v_f * (kLog2Table[v] + log_cnt);
+ } else {
+ return (float)(LOG_2_RECIPROCAL * v * log((double)v));
+ }
+}
+
+float VP8LFastLog2Slow(int v) {
+ assert(v >= LOG_LOOKUP_IDX_MAX);
+ if (v < APPROX_LOG_MAX) {
+ int log_cnt = 0;
+ while (v >= LOG_LOOKUP_IDX_MAX) {
+ ++log_cnt;
+ v = v >> 1;
+ }
+ return kLog2Table[v] + log_cnt;
+ } else {
+ return (float)(LOG_2_RECIPROCAL * log((double)v));
+ }
+}
+
+//------------------------------------------------------------------------------
+// Image transforms.
+
+// In-place sum of each component with mod 256.
+static WEBP_INLINE void AddPixelsEq(uint32_t* a, uint32_t b) {
+ const uint32_t alpha_and_green = (*a & 0xff00ff00u) + (b & 0xff00ff00u);
+ const uint32_t red_and_blue = (*a & 0x00ff00ffu) + (b & 0x00ff00ffu);
+ *a = (alpha_and_green & 0xff00ff00u) | (red_and_blue & 0x00ff00ffu);
+}
+
+static WEBP_INLINE uint32_t Average2(uint32_t a0, uint32_t a1) {
+ return (((a0 ^ a1) & 0xfefefefeL) >> 1) + (a0 & a1);
+}
+
+static WEBP_INLINE uint32_t Average3(uint32_t a0, uint32_t a1, uint32_t a2) {
+ return Average2(Average2(a0, a2), a1);
+}
+
+static WEBP_INLINE uint32_t Average4(uint32_t a0, uint32_t a1,
+ uint32_t a2, uint32_t a3) {
+ return Average2(Average2(a0, a1), Average2(a2, a3));
+}
+
+static WEBP_INLINE uint32_t Clip255(uint32_t a) {
+ if (a < 256) {
+ return a;
+ }
+ // return 0, when a is a negative integer.
+ // return 255, when a is positive.
+ return ~a >> 24;
+}
+
+static WEBP_INLINE int AddSubtractComponentFull(int a, int b, int c) {
+ return Clip255(a + b - c);
+}
+
+static WEBP_INLINE uint32_t ClampedAddSubtractFull(uint32_t c0, uint32_t c1,
+ uint32_t c2) {
+ const int a = AddSubtractComponentFull(c0 >> 24, c1 >> 24, c2 >> 24);
+ const int r = AddSubtractComponentFull((c0 >> 16) & 0xff,
+ (c1 >> 16) & 0xff,
+ (c2 >> 16) & 0xff);
+ const int g = AddSubtractComponentFull((c0 >> 8) & 0xff,
+ (c1 >> 8) & 0xff,
+ (c2 >> 8) & 0xff);
+ const int b = AddSubtractComponentFull(c0 & 0xff, c1 & 0xff, c2 & 0xff);
+ return (a << 24) | (r << 16) | (g << 8) | b;
+}
+
+static WEBP_INLINE int AddSubtractComponentHalf(int a, int b) {
+ return Clip255(a + (a - b) / 2);
+}
+
+static WEBP_INLINE uint32_t ClampedAddSubtractHalf(uint32_t c0, uint32_t c1,
+ uint32_t c2) {
+ const uint32_t ave = Average2(c0, c1);
+ const int a = AddSubtractComponentHalf(ave >> 24, c2 >> 24);
+ const int r = AddSubtractComponentHalf((ave >> 16) & 0xff, (c2 >> 16) & 0xff);
+ const int g = AddSubtractComponentHalf((ave >> 8) & 0xff, (c2 >> 8) & 0xff);
+ const int b = AddSubtractComponentHalf((ave >> 0) & 0xff, (c2 >> 0) & 0xff);
+ return (a << 24) | (r << 16) | (g << 8) | b;
+}
+
+static WEBP_INLINE int Sub3(int a, int b, int c) {
+ const int pb = b - c;
+ const int pa = a - c;
+ return abs(pb) - abs(pa);
+}
+
+static WEBP_INLINE uint32_t Select(uint32_t a, uint32_t b, uint32_t c) {
+ const int pa_minus_pb =
+ Sub3((a >> 24) , (b >> 24) , (c >> 24) ) +
+ Sub3((a >> 16) & 0xff, (b >> 16) & 0xff, (c >> 16) & 0xff) +
+ Sub3((a >> 8) & 0xff, (b >> 8) & 0xff, (c >> 8) & 0xff) +
+ Sub3((a ) & 0xff, (b ) & 0xff, (c ) & 0xff);
+ return (pa_minus_pb <= 0) ? a : b;
+}
+
+//------------------------------------------------------------------------------
+// Predictors
+
+static uint32_t Predictor0(uint32_t left, const uint32_t* const top) {
+ (void)top;
+ (void)left;
+ return ARGB_BLACK;
+}
+static uint32_t Predictor1(uint32_t left, const uint32_t* const top) {
+ (void)top;
+ return left;
+}
+static uint32_t Predictor2(uint32_t left, const uint32_t* const top) {
+ (void)left;
+ return top[0];
+}
+static uint32_t Predictor3(uint32_t left, const uint32_t* const top) {
+ (void)left;
+ return top[1];
+}
+static uint32_t Predictor4(uint32_t left, const uint32_t* const top) {
+ (void)left;
+ return top[-1];
+}
+static uint32_t Predictor5(uint32_t left, const uint32_t* const top) {
+ const uint32_t pred = Average3(left, top[0], top[1]);
+ return pred;
+}
+static uint32_t Predictor6(uint32_t left, const uint32_t* const top) {
+ const uint32_t pred = Average2(left, top[-1]);
+ return pred;
+}
+static uint32_t Predictor7(uint32_t left, const uint32_t* const top) {
+ const uint32_t pred = Average2(left, top[0]);
+ return pred;
+}
+static uint32_t Predictor8(uint32_t left, const uint32_t* const top) {
+ const uint32_t pred = Average2(top[-1], top[0]);
+ (void)left;
+ return pred;
+}
+static uint32_t Predictor9(uint32_t left, const uint32_t* const top) {
+ const uint32_t pred = Average2(top[0], top[1]);
+ (void)left;
+ return pred;
+}
+static uint32_t Predictor10(uint32_t left, const uint32_t* const top) {
+ const uint32_t pred = Average4(left, top[-1], top[0], top[1]);
+ return pred;
+}
+static uint32_t Predictor11(uint32_t left, const uint32_t* const top) {
+ const uint32_t pred = VP8LSelect(top[0], left, top[-1]);
+ return pred;
+}
+static uint32_t Predictor12(uint32_t left, const uint32_t* const top) {
+ const uint32_t pred = VP8LClampedAddSubtractFull(left, top[0], top[-1]);
+ return pred;
+}
+static uint32_t Predictor13(uint32_t left, const uint32_t* const top) {
+ const uint32_t pred = VP8LClampedAddSubtractHalf(left, top[0], top[-1]);
+ return pred;
+}
+
+// TODO(vikasa): Export the predictor array, to allow SSE2 variants.
+typedef uint32_t (*PredictorFunc)(uint32_t left, const uint32_t* const top);
+static const PredictorFunc kPredictors[16] = {
+ Predictor0, Predictor1, Predictor2, Predictor3,
+ Predictor4, Predictor5, Predictor6, Predictor7,
+ Predictor8, Predictor9, Predictor10, Predictor11,
+ Predictor12, Predictor13,
+ Predictor0, Predictor0 // <- padding security sentinels
+};
+
+// TODO(vikasa): Replace 256 etc with defines.
+static float PredictionCostSpatial(const int* counts,
+ int weight_0, double exp_val) {
+ const int significant_symbols = 16;
+ const double exp_decay_factor = 0.6;
+ double bits = weight_0 * counts[0];
+ int i;
+ for (i = 1; i < significant_symbols; ++i) {
+ bits += exp_val * (counts[i] + counts[256 - i]);
+ exp_val *= exp_decay_factor;
+ }
+ return (float)(-0.1 * bits);
+}
+
+// Compute the combined Shanon's entropy for distribution {X} and {X+Y}
+static float CombinedShannonEntropy(const int* const X,
+ const int* const Y, int n) {
+ int i;
+ double retval = 0.;
+ int sumX = 0, sumXY = 0;
+ for (i = 0; i < n; ++i) {
+ const int x = X[i];
+ const int xy = X[i] + Y[i];
+ if (x != 0) {
+ sumX += x;
+ retval -= VP8LFastSLog2(x);
+ }
+ if (xy != 0) {
+ sumXY += xy;
+ retval -= VP8LFastSLog2(xy);
+ }
+ }
+ retval += VP8LFastSLog2(sumX) + VP8LFastSLog2(sumXY);
+ return (float)retval;
+}
+
+static float PredictionCostSpatialHistogram(int accumulated[4][256],
+ int tile[4][256]) {
+ int i;
+ double retval = 0;
+ for (i = 0; i < 4; ++i) {
+ const double kExpValue = 0.94;
+ retval += PredictionCostSpatial(tile[i], 1, kExpValue);
+ retval += CombinedShannonEntropy(tile[i], accumulated[i], 256);
+ }
+ return (float)retval;
+}
+
+static int GetBestPredictorForTile(int width, int height,
+ int tile_x, int tile_y, int bits,
+ int accumulated[4][256],
+ const uint32_t* const argb_scratch) {
+ const int kNumPredModes = 14;
+ const int col_start = tile_x << bits;
+ const int row_start = tile_y << bits;
+ const int tile_size = 1 << bits;
+ const int ymax = (tile_size <= height - row_start) ?
+ tile_size : height - row_start;
+ const int xmax = (tile_size <= width - col_start) ?
+ tile_size : width - col_start;
+ int histo[4][256];
+ float best_diff = MAX_DIFF_COST;
+ int best_mode = 0;
+
+ int mode;
+ for (mode = 0; mode < kNumPredModes; ++mode) {
+ const uint32_t* current_row = argb_scratch;
+ const PredictorFunc pred_func = kPredictors[mode];
+ float cur_diff;
+ int y;
+ memset(&histo[0][0], 0, sizeof(histo));
+ for (y = 0; y < ymax; ++y) {
+ int x;
+ const int row = row_start + y;
+ const uint32_t* const upper_row = current_row;
+ current_row = upper_row + width;
+ for (x = 0; x < xmax; ++x) {
+ const int col = col_start + x;
+ uint32_t predict;
+ uint32_t predict_diff;
+ if (row == 0) {
+ predict = (col == 0) ? ARGB_BLACK : current_row[col - 1]; // Left.
+ } else if (col == 0) {
+ predict = upper_row[col]; // Top.
+ } else {
+ predict = pred_func(current_row[col - 1], upper_row + col);
+ }
+ predict_diff = VP8LSubPixels(current_row[col], predict);
+ ++histo[0][predict_diff >> 24];
+ ++histo[1][((predict_diff >> 16) & 0xff)];
+ ++histo[2][((predict_diff >> 8) & 0xff)];
+ ++histo[3][(predict_diff & 0xff)];
+ }
+ }
+ cur_diff = PredictionCostSpatialHistogram(accumulated, histo);
+ if (cur_diff < best_diff) {
+ best_diff = cur_diff;
+ best_mode = mode;
+ }
+ }
+
+ return best_mode;
+}
+
+static void CopyTileWithPrediction(int width, int height,
+ int tile_x, int tile_y, int bits, int mode,
+ const uint32_t* const argb_scratch,
+ uint32_t* const argb) {
+ const int col_start = tile_x << bits;
+ const int row_start = tile_y << bits;
+ const int tile_size = 1 << bits;
+ const int ymax = (tile_size <= height - row_start) ?
+ tile_size : height - row_start;
+ const int xmax = (tile_size <= width - col_start) ?
+ tile_size : width - col_start;
+ const PredictorFunc pred_func = kPredictors[mode];
+ const uint32_t* current_row = argb_scratch;
+
+ int y;
+ for (y = 0; y < ymax; ++y) {
+ int x;
+ const int row = row_start + y;
+ const uint32_t* const upper_row = current_row;
+ current_row = upper_row + width;
+ for (x = 0; x < xmax; ++x) {
+ const int col = col_start + x;
+ const int pix = row * width + col;
+ uint32_t predict;
+ if (row == 0) {
+ predict = (col == 0) ? ARGB_BLACK : current_row[col - 1]; // Left.
+ } else if (col == 0) {
+ predict = upper_row[col]; // Top.
+ } else {
+ predict = pred_func(current_row[col - 1], upper_row + col);
+ }
+ argb[pix] = VP8LSubPixels(current_row[col], predict);
+ }
+ }
+}
+
+void VP8LResidualImage(int width, int height, int bits,
+ uint32_t* const argb, uint32_t* const argb_scratch,
+ uint32_t* const image) {
+ const int max_tile_size = 1 << bits;
+ const int tiles_per_row = VP8LSubSampleSize(width, bits);
+ const int tiles_per_col = VP8LSubSampleSize(height, bits);
+ uint32_t* const upper_row = argb_scratch;
+ uint32_t* const current_tile_rows = argb_scratch + width;
+ int tile_y;
+ int histo[4][256];
+ memset(histo, 0, sizeof(histo));
+ for (tile_y = 0; tile_y < tiles_per_col; ++tile_y) {
+ const int tile_y_offset = tile_y * max_tile_size;
+ const int this_tile_height =
+ (tile_y < tiles_per_col - 1) ? max_tile_size : height - tile_y_offset;
+ int tile_x;
+ if (tile_y > 0) {
+ memcpy(upper_row, current_tile_rows + (max_tile_size - 1) * width,
+ width * sizeof(*upper_row));
+ }
+ memcpy(current_tile_rows, &argb[tile_y_offset * width],
+ this_tile_height * width * sizeof(*current_tile_rows));
+ for (tile_x = 0; tile_x < tiles_per_row; ++tile_x) {
+ int pred;
+ int y;
+ const int tile_x_offset = tile_x * max_tile_size;
+ int all_x_max = tile_x_offset + max_tile_size;
+ if (all_x_max > width) {
+ all_x_max = width;
+ }
+ pred = GetBestPredictorForTile(width, height, tile_x, tile_y, bits, histo,
+ argb_scratch);
+ image[tile_y * tiles_per_row + tile_x] = 0xff000000u | (pred << 8);
+ CopyTileWithPrediction(width, height, tile_x, tile_y, bits, pred,
+ argb_scratch, argb);
+ for (y = 0; y < max_tile_size; ++y) {
+ int ix;
+ int all_x;
+ int all_y = tile_y_offset + y;
+ if (all_y >= height) {
+ break;
+ }
+ ix = all_y * width + tile_x_offset;
+ for (all_x = tile_x_offset; all_x < all_x_max; ++all_x, ++ix) {
+ const uint32_t a = argb[ix];
+ ++histo[0][a >> 24];
+ ++histo[1][((a >> 16) & 0xff)];
+ ++histo[2][((a >> 8) & 0xff)];
+ ++histo[3][(a & 0xff)];
+ }
+ }
+ }
+ }
+}
+
+// Inverse prediction.
+static void PredictorInverseTransform(const VP8LTransform* const transform,
+ int y_start, int y_end, uint32_t* data) {
+ const int width = transform->xsize_;
+ if (y_start == 0) { // First Row follows the L (mode=1) mode.
+ int x;
+ const uint32_t pred0 = Predictor0(data[-1], NULL);
+ AddPixelsEq(data, pred0);
+ for (x = 1; x < width; ++x) {
+ const uint32_t pred1 = Predictor1(data[x - 1], NULL);
+ AddPixelsEq(data + x, pred1);
+ }
+ data += width;
+ ++y_start;
+ }
+
+ {
+ int y = y_start;
+ const int mask = (1 << transform->bits_) - 1;
+ const int tiles_per_row = VP8LSubSampleSize(width, transform->bits_);
+ const uint32_t* pred_mode_base =
+ transform->data_ + (y >> transform->bits_) * tiles_per_row;
+
+ while (y < y_end) {
+ int x;
+ const uint32_t pred2 = Predictor2(data[-1], data - width);
+ const uint32_t* pred_mode_src = pred_mode_base;
+ PredictorFunc pred_func;
+
+ // First pixel follows the T (mode=2) mode.
+ AddPixelsEq(data, pred2);
+
+ // .. the rest:
+ pred_func = kPredictors[((*pred_mode_src++) >> 8) & 0xf];
+ for (x = 1; x < width; ++x) {
+ uint32_t pred;
+ if ((x & mask) == 0) { // start of tile. Read predictor function.
+ pred_func = kPredictors[((*pred_mode_src++) >> 8) & 0xf];
+ }
+ pred = pred_func(data[x - 1], data + x - width);
+ AddPixelsEq(data + x, pred);
+ }
+ data += width;
+ ++y;
+ if ((y & mask) == 0) { // Use the same mask, since tiles are squares.
+ pred_mode_base += tiles_per_row;
+ }
+ }
+ }
+}
+
+static void SubtractGreenFromBlueAndRed(uint32_t* argb_data, int num_pixs) {
+ int i = 0;
+ for (; i < num_pixs; ++i) {
+ const uint32_t argb = argb_data[i];
+ const uint32_t green = (argb >> 8) & 0xff;
+ const uint32_t new_r = (((argb >> 16) & 0xff) - green) & 0xff;
+ const uint32_t new_b = ((argb & 0xff) - green) & 0xff;
+ argb_data[i] = (argb & 0xff00ff00) | (new_r << 16) | new_b;
+ }
+}
+
+// Add green to blue and red channels (i.e. perform the inverse transform of
+// 'subtract green').
+static void AddGreenToBlueAndRed(uint32_t* data, const uint32_t* data_end) {
+ while (data < data_end) {
+ const uint32_t argb = *data;
+ const uint32_t green = ((argb >> 8) & 0xff);
+ uint32_t red_blue = (argb & 0x00ff00ffu);
+ red_blue += (green << 16) | green;
+ red_blue &= 0x00ff00ffu;
+ *data++ = (argb & 0xff00ff00u) | red_blue;
+ }
+}
+
+typedef struct {
+ // Note: the members are uint8_t, so that any negative values are
+ // automatically converted to "mod 256" values.
+ uint8_t green_to_red_;
+ uint8_t green_to_blue_;
+ uint8_t red_to_blue_;
+} Multipliers;
+
+static WEBP_INLINE void MultipliersClear(Multipliers* m) {
+ m->green_to_red_ = 0;
+ m->green_to_blue_ = 0;
+ m->red_to_blue_ = 0;
+}
+
+static WEBP_INLINE uint32_t ColorTransformDelta(int8_t color_pred,
+ int8_t color) {
+ return (uint32_t)((int)(color_pred) * color) >> 5;
+}
+
+static WEBP_INLINE void ColorCodeToMultipliers(uint32_t color_code,
+ Multipliers* const m) {
+ m->green_to_red_ = (color_code >> 0) & 0xff;
+ m->green_to_blue_ = (color_code >> 8) & 0xff;
+ m->red_to_blue_ = (color_code >> 16) & 0xff;
+}
+
+static WEBP_INLINE uint32_t MultipliersToColorCode(Multipliers* const m) {
+ return 0xff000000u |
+ ((uint32_t)(m->red_to_blue_) << 16) |
+ ((uint32_t)(m->green_to_blue_) << 8) |
+ m->green_to_red_;
+}
+
+static WEBP_INLINE uint32_t TransformColor(const Multipliers* const m,
+ uint32_t argb, int inverse) {
+ const uint32_t green = argb >> 8;
+ const uint32_t red = argb >> 16;
+ uint32_t new_red = red;
+ uint32_t new_blue = argb;
+
+ if (inverse) {
+ new_red += ColorTransformDelta(m->green_to_red_, green);
+ new_red &= 0xff;
+ new_blue += ColorTransformDelta(m->green_to_blue_, green);
+ new_blue += ColorTransformDelta(m->red_to_blue_, new_red);
+ new_blue &= 0xff;
+ } else {
+ new_red -= ColorTransformDelta(m->green_to_red_, green);
+ new_red &= 0xff;
+ new_blue -= ColorTransformDelta(m->green_to_blue_, green);
+ new_blue -= ColorTransformDelta(m->red_to_blue_, red);
+ new_blue &= 0xff;
+ }
+ return (argb & 0xff00ff00u) | (new_red << 16) | (new_blue);
+}
+
+static WEBP_INLINE uint8_t TransformColorRed(uint8_t green_to_red,
+ uint32_t argb) {
+ const uint32_t green = argb >> 8;
+ uint32_t new_red = argb >> 16;
+ new_red -= ColorTransformDelta(green_to_red, green);
+ return (new_red & 0xff);
+}
+
+static WEBP_INLINE uint8_t TransformColorBlue(uint8_t green_to_blue,
+ uint8_t red_to_blue,
+ uint32_t argb) {
+ const uint32_t green = argb >> 8;
+ const uint32_t red = argb >> 16;
+ uint8_t new_blue = argb;
+ new_blue -= ColorTransformDelta(green_to_blue, green);
+ new_blue -= ColorTransformDelta(red_to_blue, red);
+ return (new_blue & 0xff);
+}
+
+static WEBP_INLINE int SkipRepeatedPixels(const uint32_t* const argb,
+ int ix, int xsize) {
+ const uint32_t v = argb[ix];
+ if (ix >= xsize + 3) {
+ if (v == argb[ix - xsize] &&
+ argb[ix - 1] == argb[ix - xsize - 1] &&
+ argb[ix - 2] == argb[ix - xsize - 2] &&
+ argb[ix - 3] == argb[ix - xsize - 3]) {
+ return 1;
+ }
+ return v == argb[ix - 3] && v == argb[ix - 2] && v == argb[ix - 1];
+ } else if (ix >= 3) {
+ return v == argb[ix - 3] && v == argb[ix - 2] && v == argb[ix - 1];
+ }
+ return 0;
+}
+
+static float PredictionCostCrossColor(const int accumulated[256],
+ const int counts[256]) {
+ // Favor low entropy, locally and globally.
+ // Favor small absolute values for PredictionCostSpatial
+ static const double kExpValue = 2.4;
+ return CombinedShannonEntropy(counts, accumulated, 256) +
+ PredictionCostSpatial(counts, 3, kExpValue);
+}
+
+static Multipliers GetBestColorTransformForTile(
+ int tile_x, int tile_y, int bits,
+ Multipliers prevX,
+ Multipliers prevY,
+ int step, int xsize, int ysize,
+ int* accumulated_red_histo,
+ int* accumulated_blue_histo,
+ const uint32_t* const argb) {
+ float best_diff = MAX_DIFF_COST;
+ float cur_diff;
+ const int halfstep = step / 2;
+ const int max_tile_size = 1 << bits;
+ const int tile_y_offset = tile_y * max_tile_size;
+ const int tile_x_offset = tile_x * max_tile_size;
+ int green_to_red;
+ int green_to_blue;
+ int red_to_blue;
+ int all_x_max = tile_x_offset + max_tile_size;
+ int all_y_max = tile_y_offset + max_tile_size;
+ Multipliers best_tx;
+ MultipliersClear(&best_tx);
+ if (all_x_max > xsize) {
+ all_x_max = xsize;
+ }
+ if (all_y_max > ysize) {
+ all_y_max = ysize;
+ }
+
+ for (green_to_red = -64; green_to_red <= 64; green_to_red += halfstep) {
+ int histo[256] = { 0 };
+ int all_y;
+
+ for (all_y = tile_y_offset; all_y < all_y_max; ++all_y) {
+ int ix = all_y * xsize + tile_x_offset;
+ int all_x;
+ for (all_x = tile_x_offset; all_x < all_x_max; ++all_x, ++ix) {
+ if (SkipRepeatedPixels(argb, ix, xsize)) {
+ continue;
+ }
+ ++histo[TransformColorRed(green_to_red, argb[ix])]; // red.
+ }
+ }
+ cur_diff = PredictionCostCrossColor(&accumulated_red_histo[0], &histo[0]);
+ if ((uint8_t)green_to_red == prevX.green_to_red_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if ((uint8_t)green_to_red == prevY.green_to_red_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if (green_to_red == 0) {
+ cur_diff -= 3;
+ }
+ if (cur_diff < best_diff) {
+ best_diff = cur_diff;
+ best_tx.green_to_red_ = green_to_red;
+ }
+ }
+ best_diff = MAX_DIFF_COST;
+ for (green_to_blue = -32; green_to_blue <= 32; green_to_blue += step) {
+ for (red_to_blue = -32; red_to_blue <= 32; red_to_blue += step) {
+ int all_y;
+ int histo[256] = { 0 };
+ for (all_y = tile_y_offset; all_y < all_y_max; ++all_y) {
+ int all_x;
+ int ix = all_y * xsize + tile_x_offset;
+ for (all_x = tile_x_offset; all_x < all_x_max; ++all_x, ++ix) {
+ if (SkipRepeatedPixels(argb, ix, xsize)) {
+ continue;
+ }
+ ++histo[TransformColorBlue(green_to_blue, red_to_blue, argb[ix])];
+ }
+ }
+ cur_diff =
+ PredictionCostCrossColor(&accumulated_blue_histo[0], &histo[0]);
+ if ((uint8_t)green_to_blue == prevX.green_to_blue_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if ((uint8_t)green_to_blue == prevY.green_to_blue_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if ((uint8_t)red_to_blue == prevX.red_to_blue_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if ((uint8_t)red_to_blue == prevY.red_to_blue_) {
+ cur_diff -= 3; // favor keeping the areas locally similar
+ }
+ if (green_to_blue == 0) {
+ cur_diff -= 3;
+ }
+ if (red_to_blue == 0) {
+ cur_diff -= 3;
+ }
+ if (cur_diff < best_diff) {
+ best_diff = cur_diff;
+ best_tx.green_to_blue_ = green_to_blue;
+ best_tx.red_to_blue_ = red_to_blue;
+ }
+ }
+ }
+ return best_tx;
+}
+
+static void CopyTileWithColorTransform(int xsize, int ysize,
+ int tile_x, int tile_y, int bits,
+ Multipliers color_transform,
+ uint32_t* const argb) {
+ int y;
+ int xscan = 1 << bits;
+ int yscan = 1 << bits;
+ tile_x <<= bits;
+ tile_y <<= bits;
+ if (xscan > xsize - tile_x) {
+ xscan = xsize - tile_x;
+ }
+ if (yscan > ysize - tile_y) {
+ yscan = ysize - tile_y;
+ }
+ yscan += tile_y;
+ for (y = tile_y; y < yscan; ++y) {
+ int ix = y * xsize + tile_x;
+ const int end_ix = ix + xscan;
+ for (; ix < end_ix; ++ix) {
+ argb[ix] = TransformColor(&color_transform, argb[ix], 0);
+ }
+ }
+}
+
+void VP8LColorSpaceTransform(int width, int height, int bits, int step,
+ uint32_t* const argb, uint32_t* image) {
+ const int max_tile_size = 1 << bits;
+ int tile_xsize = VP8LSubSampleSize(width, bits);
+ int tile_ysize = VP8LSubSampleSize(height, bits);
+ int accumulated_red_histo[256] = { 0 };
+ int accumulated_blue_histo[256] = { 0 };
+ int tile_y;
+ int tile_x;
+ Multipliers prevX;
+ Multipliers prevY;
+ MultipliersClear(&prevY);
+ MultipliersClear(&prevX);
+ for (tile_y = 0; tile_y < tile_ysize; ++tile_y) {
+ for (tile_x = 0; tile_x < tile_xsize; ++tile_x) {
+ Multipliers color_transform;
+ int all_x_max;
+ int y;
+ const int tile_y_offset = tile_y * max_tile_size;
+ const int tile_x_offset = tile_x * max_tile_size;
+ if (tile_y != 0) {
+ ColorCodeToMultipliers(image[tile_y * tile_xsize + tile_x - 1], &prevX);
+ ColorCodeToMultipliers(image[(tile_y - 1) * tile_xsize + tile_x],
+ &prevY);
+ } else if (tile_x != 0) {
+ ColorCodeToMultipliers(image[tile_y * tile_xsize + tile_x - 1], &prevX);
+ }
+ color_transform =
+ GetBestColorTransformForTile(tile_x, tile_y, bits,
+ prevX, prevY,
+ step, width, height,
+ &accumulated_red_histo[0],
+ &accumulated_blue_histo[0],
+ argb);
+ image[tile_y * tile_xsize + tile_x] =
+ MultipliersToColorCode(&color_transform);
+ CopyTileWithColorTransform(width, height, tile_x, tile_y, bits,
+ color_transform, argb);
+
+ // Gather accumulated histogram data.
+ all_x_max = tile_x_offset + max_tile_size;
+ if (all_x_max > width) {
+ all_x_max = width;
+ }
+ for (y = 0; y < max_tile_size; ++y) {
+ int ix;
+ int all_x;
+ int all_y = tile_y_offset + y;
+ if (all_y >= height) {
+ break;
+ }
+ ix = all_y * width + tile_x_offset;
+ for (all_x = tile_x_offset; all_x < all_x_max; ++all_x, ++ix) {
+ if (ix >= 2 &&
+ argb[ix] == argb[ix - 2] &&
+ argb[ix] == argb[ix - 1]) {
+ continue; // repeated pixels are handled by backward references
+ }
+ if (ix >= width + 2 &&
+ argb[ix - 2] == argb[ix - width - 2] &&
+ argb[ix - 1] == argb[ix - width - 1] &&
+ argb[ix] == argb[ix - width]) {
+ continue; // repeated pixels are handled by backward references
+ }
+ ++accumulated_red_histo[(argb[ix] >> 16) & 0xff];
+ ++accumulated_blue_histo[argb[ix] & 0xff];
+ }
+ }
+ }
+ }
+}
+
+// Color space inverse transform.
+static void ColorSpaceInverseTransform(const VP8LTransform* const transform,
+ int y_start, int y_end, uint32_t* data) {
+ const int width = transform->xsize_;
+ const int mask = (1 << transform->bits_) - 1;
+ const int tiles_per_row = VP8LSubSampleSize(width, transform->bits_);
+ int y = y_start;
+ const uint32_t* pred_row =
+ transform->data_ + (y >> transform->bits_) * tiles_per_row;
+
+ while (y < y_end) {
+ const uint32_t* pred = pred_row;
+ Multipliers m = { 0, 0, 0 };
+ int x;
+
+ for (x = 0; x < width; ++x) {
+ if ((x & mask) == 0) ColorCodeToMultipliers(*pred++, &m);
+ data[x] = TransformColor(&m, data[x], 1);
+ }
+ data += width;
+ ++y;
+ if ((y & mask) == 0) pred_row += tiles_per_row;;
+ }
+}
+
+// Separate out pixels packed together using pixel-bundling.
+// We define two methods for ARGB data (uint32_t) and alpha-only data (uint8_t).
+#define COLOR_INDEX_INVERSE(FUNC_NAME, TYPE, GET_INDEX, GET_VALUE) \
+void FUNC_NAME(const VP8LTransform* const transform, \
+ int y_start, int y_end, const TYPE* src, TYPE* dst) { \
+ int y; \
+ const int bits_per_pixel = 8 >> transform->bits_; \
+ const int width = transform->xsize_; \
+ const uint32_t* const color_map = transform->data_; \
+ if (bits_per_pixel < 8) { \
+ const int pixels_per_byte = 1 << transform->bits_; \
+ const int count_mask = pixels_per_byte - 1; \
+ const uint32_t bit_mask = (1 << bits_per_pixel) - 1; \
+ for (y = y_start; y < y_end; ++y) { \
+ uint32_t packed_pixels = 0; \
+ int x; \
+ for (x = 0; x < width; ++x) { \
+ /* We need to load fresh 'packed_pixels' once every */ \
+ /* 'pixels_per_byte' increments of x. Fortunately, pixels_per_byte */ \
+ /* is a power of 2, so can just use a mask for that, instead of */ \
+ /* decrementing a counter. */ \
+ if ((x & count_mask) == 0) packed_pixels = GET_INDEX(*src++); \
+ *dst++ = GET_VALUE(color_map[packed_pixels & bit_mask]); \
+ packed_pixels >>= bits_per_pixel; \
+ } \
+ } \
+ } else { \
+ for (y = y_start; y < y_end; ++y) { \
+ int x; \
+ for (x = 0; x < width; ++x) { \
+ *dst++ = GET_VALUE(color_map[GET_INDEX(*src++)]); \
+ } \
+ } \
+ } \
+}
+
+static WEBP_INLINE uint32_t GetARGBIndex(uint32_t idx) {
+ return (idx >> 8) & 0xff;
+}
+
+static WEBP_INLINE uint8_t GetAlphaIndex(uint8_t idx) {
+ return idx;
+}
+
+static WEBP_INLINE uint32_t GetARGBValue(uint32_t val) {
+ return val;
+}
+
+static WEBP_INLINE uint8_t GetAlphaValue(uint32_t val) {
+ return (val >> 8) & 0xff;
+}
+
+static COLOR_INDEX_INVERSE(ColorIndexInverseTransform, uint32_t, GetARGBIndex,
+ GetARGBValue)
+COLOR_INDEX_INVERSE(VP8LColorIndexInverseTransformAlpha, uint8_t, GetAlphaIndex,
+ GetAlphaValue)
+
+#undef COLOR_INDEX_INVERSE
+
+void VP8LInverseTransform(const VP8LTransform* const transform,
+ int row_start, int row_end,
+ const uint32_t* const in, uint32_t* const out) {
+ const int width = transform->xsize_;
+ assert(row_start < row_end);
+ assert(row_end <= transform->ysize_);
+ switch (transform->type_) {
+ case SUBTRACT_GREEN:
+ VP8LAddGreenToBlueAndRed(out, out + (row_end - row_start) * width);
+ break;
+ case PREDICTOR_TRANSFORM:
+ PredictorInverseTransform(transform, row_start, row_end, out);
+ if (row_end != transform->ysize_) {
+ // The last predicted row in this iteration will be the top-pred row
+ // for the first row in next iteration.
+ memcpy(out - width, out + (row_end - row_start - 1) * width,
+ width * sizeof(*out));
+ }
+ break;
+ case CROSS_COLOR_TRANSFORM:
+ ColorSpaceInverseTransform(transform, row_start, row_end, out);
+ break;
+ case COLOR_INDEXING_TRANSFORM:
+ if (in == out && transform->bits_ > 0) {
+ // Move packed pixels to the end of unpacked region, so that unpacking
+ // can occur seamlessly.
+ // Also, note that this is the only transform that applies on
+ // the effective width of VP8LSubSampleSize(xsize_, bits_). All other
+ // transforms work on effective width of xsize_.
+ const int out_stride = (row_end - row_start) * width;
+ const int in_stride = (row_end - row_start) *
+ VP8LSubSampleSize(transform->xsize_, transform->bits_);
+ uint32_t* const src = out + out_stride - in_stride;
+ memmove(src, out, in_stride * sizeof(*src));
+ ColorIndexInverseTransform(transform, row_start, row_end, src, out);
+ } else {
+ ColorIndexInverseTransform(transform, row_start, row_end, in, out);
+ }
+ break;
+ }
+}
+
+//------------------------------------------------------------------------------
+// Color space conversion.
+
+static int is_big_endian(void) {
+ static const union {
+ uint16_t w;
+ uint8_t b[2];
+ } tmp = { 1 };
+ return (tmp.b[0] != 1);
+}
+
+static void ConvertBGRAToRGB(const uint32_t* src,
+ int num_pixels, uint8_t* dst) {
+ const uint32_t* const src_end = src + num_pixels;
+ while (src < src_end) {
+ const uint32_t argb = *src++;
+ *dst++ = (argb >> 16) & 0xff;
+ *dst++ = (argb >> 8) & 0xff;
+ *dst++ = (argb >> 0) & 0xff;
+ }
+}
+
+static void ConvertBGRAToRGBA(const uint32_t* src,
+ int num_pixels, uint8_t* dst) {
+ const uint32_t* const src_end = src + num_pixels;
+ while (src < src_end) {
+ const uint32_t argb = *src++;
+ *dst++ = (argb >> 16) & 0xff;
+ *dst++ = (argb >> 8) & 0xff;
+ *dst++ = (argb >> 0) & 0xff;
+ *dst++ = (argb >> 24) & 0xff;
+ }
+}
+
+static void ConvertBGRAToRGBA4444(const uint32_t* src,
+ int num_pixels, uint8_t* dst) {
+ const uint32_t* const src_end = src + num_pixels;
+ while (src < src_end) {
+ const uint32_t argb = *src++;
+ const uint8_t rg = ((argb >> 16) & 0xf0) | ((argb >> 12) & 0xf);
+ const uint8_t ba = ((argb >> 0) & 0xf0) | ((argb >> 28) & 0xf);
+#ifdef WEBP_SWAP_16BIT_CSP
+ *dst++ = ba;
+ *dst++ = rg;
+#else
+ *dst++ = rg;
+ *dst++ = ba;
+#endif
+ }
+}
+
+static void ConvertBGRAToRGB565(const uint32_t* src,
+ int num_pixels, uint8_t* dst) {
+ const uint32_t* const src_end = src + num_pixels;
+ while (src < src_end) {
+ const uint32_t argb = *src++;
+ const uint8_t rg = ((argb >> 16) & 0xf8) | ((argb >> 13) & 0x7);
+ const uint8_t gb = ((argb >> 5) & 0xe0) | ((argb >> 3) & 0x1f);
+#ifdef WEBP_SWAP_16BIT_CSP
+ *dst++ = gb;
+ *dst++ = rg;
+#else
+ *dst++ = rg;
+ *dst++ = gb;
+#endif
+ }
+}
+
+static void ConvertBGRAToBGR(const uint32_t* src,
+ int num_pixels, uint8_t* dst) {
+ const uint32_t* const src_end = src + num_pixels;
+ while (src < src_end) {
+ const uint32_t argb = *src++;
+ *dst++ = (argb >> 0) & 0xff;
+ *dst++ = (argb >> 8) & 0xff;
+ *dst++ = (argb >> 16) & 0xff;
+ }
+}
+
+static void CopyOrSwap(const uint32_t* src, int num_pixels, uint8_t* dst,
+ int swap_on_big_endian) {
+ if (is_big_endian() == swap_on_big_endian) {
+ const uint32_t* const src_end = src + num_pixels;
+ while (src < src_end) {
+ uint32_t argb = *src++;
+
+#if !defined(__BIG_ENDIAN__)
+#if !defined(WEBP_REFERENCE_IMPLEMENTATION)
+#if defined(__i386__) || defined(__x86_64__)
+ __asm__ volatile("bswap %0" : "=r"(argb) : "0"(argb));
+ *(uint32_t*)dst = argb;
+#elif defined(_MSC_VER)
+ argb = _byteswap_ulong(argb);
+ *(uint32_t*)dst = argb;
+#else
+ dst[0] = (argb >> 24) & 0xff;
+ dst[1] = (argb >> 16) & 0xff;
+ dst[2] = (argb >> 8) & 0xff;
+ dst[3] = (argb >> 0) & 0xff;
+#endif
+#else // WEBP_REFERENCE_IMPLEMENTATION
+ dst[0] = (argb >> 24) & 0xff;
+ dst[1] = (argb >> 16) & 0xff;
+ dst[2] = (argb >> 8) & 0xff;
+ dst[3] = (argb >> 0) & 0xff;
+#endif
+#else // __BIG_ENDIAN__
+ dst[0] = (argb >> 0) & 0xff;
+ dst[1] = (argb >> 8) & 0xff;
+ dst[2] = (argb >> 16) & 0xff;
+ dst[3] = (argb >> 24) & 0xff;
+#endif
+ dst += sizeof(argb);
+ }
+ } else {
+ memcpy(dst, src, num_pixels * sizeof(*src));
+ }
+}
+
+void VP8LConvertFromBGRA(const uint32_t* const in_data, int num_pixels,
+ WEBP_CSP_MODE out_colorspace, uint8_t* const rgba) {
+ switch (out_colorspace) {
+ case MODE_RGB:
+ ConvertBGRAToRGB(in_data, num_pixels, rgba);
+ break;
+ case MODE_RGBA:
+ ConvertBGRAToRGBA(in_data, num_pixels, rgba);
+ break;
+ case MODE_rgbA:
+ ConvertBGRAToRGBA(in_data, num_pixels, rgba);
+ WebPApplyAlphaMultiply(rgba, 0, num_pixels, 1, 0);
+ break;
+ case MODE_BGR:
+ ConvertBGRAToBGR(in_data, num_pixels, rgba);
+ break;
+ case MODE_BGRA:
+ CopyOrSwap(in_data, num_pixels, rgba, 1);
+ break;
+ case MODE_bgrA:
+ CopyOrSwap(in_data, num_pixels, rgba, 1);
+ WebPApplyAlphaMultiply(rgba, 0, num_pixels, 1, 0);
+ break;
+ case MODE_ARGB:
+ CopyOrSwap(in_data, num_pixels, rgba, 0);
+ break;
+ case MODE_Argb:
+ CopyOrSwap(in_data, num_pixels, rgba, 0);
+ WebPApplyAlphaMultiply(rgba, 1, num_pixels, 1, 0);
+ break;
+ case MODE_RGBA_4444:
+ ConvertBGRAToRGBA4444(in_data, num_pixels, rgba);
+ break;
+ case MODE_rgbA_4444:
+ ConvertBGRAToRGBA4444(in_data, num_pixels, rgba);
+ WebPApplyAlphaMultiply4444(rgba, num_pixels, 1, 0);
+ break;
+ case MODE_RGB_565:
+ ConvertBGRAToRGB565(in_data, num_pixels, rgba);
+ break;
+ default:
+ assert(0); // Code flow should not reach here.
+ }
+}
+
+// Bundles multiple (1, 2, 4 or 8) pixels into a single pixel.
+void VP8LBundleColorMap(const uint8_t* const row, int width,
+ int xbits, uint32_t* const dst) {
+ int x;
+ if (xbits > 0) {
+ const int bit_depth = 1 << (3 - xbits);
+ const int mask = (1 << xbits) - 1;
+ uint32_t code = 0xff000000;
+ for (x = 0; x < width; ++x) {
+ const int xsub = x & mask;
+ if (xsub == 0) {
+ code = 0xff000000;
+ }
+ code |= row[x] << (8 + bit_depth * xsub);
+ dst[x >> xbits] = code;
+ }
+ } else {
+ for (x = 0; x < width; ++x) dst[x] = 0xff000000 | (row[x] << 8);
+ }
+}
+
+//------------------------------------------------------------------------------
+
+// TODO(vikasa): Move the SSE2 functions to lossless_dsp.c (new file), once
+// color-space conversion methods (ConvertFromBGRA) are also updated for SSE2.
+#if defined(WEBP_USE_SSE2)
+static WEBP_INLINE uint32_t ClampedAddSubtractFullSSE2(uint32_t c0, uint32_t c1,
+ uint32_t c2) {
+ const __m128i zero = _mm_setzero_si128();
+ const __m128i C0 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(c0), zero);
+ const __m128i C1 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(c1), zero);
+ const __m128i C2 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(c2), zero);
+ const __m128i V1 = _mm_add_epi16(C0, C1);
+ const __m128i V2 = _mm_sub_epi16(V1, C2);
+ const __m128i b = _mm_packus_epi16(V2, V2);
+ const uint32_t output = _mm_cvtsi128_si32(b);
+ return output;
+}
+
+static WEBP_INLINE uint32_t ClampedAddSubtractHalfSSE2(uint32_t c0, uint32_t c1,
+ uint32_t c2) {
+ const uint32_t ave = Average2(c0, c1);
+ const __m128i zero = _mm_setzero_si128();
+ const __m128i A0 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(ave), zero);
+ const __m128i B0 = _mm_unpacklo_epi8(_mm_cvtsi32_si128(c2), zero);
+ const __m128i A1 = _mm_sub_epi16(A0, B0);
+ const __m128i BgtA = _mm_cmpgt_epi16(B0, A0);
+ const __m128i A2 = _mm_sub_epi16(A1, BgtA);
+ const __m128i A3 = _mm_srai_epi16(A2, 1);
+ const __m128i A4 = _mm_add_epi16(A0, A3);
+ const __m128i A5 = _mm_packus_epi16(A4, A4);
+ const uint32_t output = _mm_cvtsi128_si32(A5);
+ return output;
+}
+
+static WEBP_INLINE uint32_t SelectSSE2(uint32_t a, uint32_t b, uint32_t c) {
+ int pa_minus_pb;
+ const __m128i zero = _mm_setzero_si128();
+ const __m128i A0 = _mm_cvtsi32_si128(a);
+ const __m128i B0 = _mm_cvtsi32_si128(b);
+ const __m128i C0 = _mm_cvtsi32_si128(c);
+ const __m128i AC0 = _mm_subs_epu8(A0, C0);
+ const __m128i CA0 = _mm_subs_epu8(C0, A0);
+ const __m128i BC0 = _mm_subs_epu8(B0, C0);
+ const __m128i CB0 = _mm_subs_epu8(C0, B0);
+ const __m128i AC = _mm_or_si128(AC0, CA0);
+ const __m128i BC = _mm_or_si128(BC0, CB0);
+ const __m128i pa = _mm_unpacklo_epi8(AC, zero); // |a - c|
+ const __m128i pb = _mm_unpacklo_epi8(BC, zero); // |b - c|
+ const __m128i diff = _mm_sub_epi16(pb, pa);
+ {
+ int16_t out[8];
+ _mm_storeu_si128((__m128i*)out, diff);
+ pa_minus_pb = out[0] + out[1] + out[2] + out[3];
+ }
+ return (pa_minus_pb <= 0) ? a : b;
+}
+
+static void SubtractGreenFromBlueAndRedSSE2(uint32_t* argb_data, int num_pixs) {
+ int i = 0;
+ const __m128i mask = _mm_set1_epi32(0x0000ff00);
+ for (; i + 4 < num_pixs; i += 4) {
+ const __m128i in = _mm_loadu_si128((__m128i*)&argb_data[i]);
+ const __m128i in_00g0 = _mm_and_si128(in, mask); // 00g0|00g0|...
+ const __m128i in_0g00 = _mm_slli_epi32(in_00g0, 8); // 0g00|0g00|...
+ const __m128i in_000g = _mm_srli_epi32(in_00g0, 8); // 000g|000g|...
+ const __m128i in_0g0g = _mm_or_si128(in_0g00, in_000g);
+ const __m128i out = _mm_sub_epi8(in, in_0g0g);
+ _mm_storeu_si128((__m128i*)&argb_data[i], out);
+ }
+ // fallthrough and finish off with plain-C
+ for (; i < num_pixs; ++i) {
+ const uint32_t argb = argb_data[i];
+ const uint32_t green = (argb >> 8) & 0xff;
+ const uint32_t new_r = (((argb >> 16) & 0xff) - green) & 0xff;
+ const uint32_t new_b = ((argb & 0xff) - green) & 0xff;
+ argb_data[i] = (argb & 0xff00ff00) | (new_r << 16) | new_b;
+ }
+}
+
+static void AddGreenToBlueAndRedSSE2(uint32_t* data, const uint32_t* data_end) {
+ const __m128i mask = _mm_set1_epi32(0x0000ff00);
+ for (; data + 4 < data_end; data += 4) {
+ const __m128i in = _mm_loadu_si128((__m128i*)data);
+ const __m128i in_00g0 = _mm_and_si128(in, mask); // 00g0|00g0|...
+ const __m128i in_0g00 = _mm_slli_epi32(in_00g0, 8); // 0g00|0g00|...
+ const __m128i in_000g = _mm_srli_epi32(in_00g0, 8); // 000g|000g|...
+ const __m128i in_0g0g = _mm_or_si128(in_0g00, in_000g);
+ const __m128i out = _mm_add_epi8(in, in_0g0g);
+ _mm_storeu_si128((__m128i*)data, out);
+ }
+ // fallthrough and finish off with plain-C
+ while (data < data_end) {
+ const uint32_t argb = *data;
+ const uint32_t green = ((argb >> 8) & 0xff);
+ uint32_t red_blue = (argb & 0x00ff00ffu);
+ red_blue += (green << 16) | green;
+ red_blue &= 0x00ff00ffu;
+ *data++ = (argb & 0xff00ff00u) | red_blue;
+ }
+}
+
+extern void VP8LDspInitSSE2(void);
+
+void VP8LDspInitSSE2(void) {
+ VP8LClampedAddSubtractFull = ClampedAddSubtractFullSSE2;
+ VP8LClampedAddSubtractHalf = ClampedAddSubtractHalfSSE2;
+ VP8LSelect = SelectSSE2;
+ VP8LSubtractGreenFromBlueAndRed = SubtractGreenFromBlueAndRedSSE2;
+ VP8LAddGreenToBlueAndRed = AddGreenToBlueAndRedSSE2;
+}
+#endif
+//------------------------------------------------------------------------------
+
+VP8LPredClampedAddSubFunc VP8LClampedAddSubtractFull;
+VP8LPredClampedAddSubFunc VP8LClampedAddSubtractHalf;
+VP8LPredSelectFunc VP8LSelect;
+VP8LSubtractGreenFromBlueAndRedFunc VP8LSubtractGreenFromBlueAndRed;
+VP8LAddGreenToBlueAndRedFunc VP8LAddGreenToBlueAndRed;
+
+void VP8LDspInit(void) {
+ VP8LClampedAddSubtractFull = ClampedAddSubtractFull;
+ VP8LClampedAddSubtractHalf = ClampedAddSubtractHalf;
+ VP8LSelect = Select;
+ VP8LSubtractGreenFromBlueAndRed = SubtractGreenFromBlueAndRed;
+ VP8LAddGreenToBlueAndRed = AddGreenToBlueAndRed;
+
+ // If defined, use CPUInfo() to overwrite some pointers with faster versions.
+ if (VP8GetCPUInfo != NULL) {
+#if defined(WEBP_USE_SSE2)
+ if (VP8GetCPUInfo(kSSE2)) {
+ VP8LDspInitSSE2();
+ }
+#endif
+ }
+}
+
+//------------------------------------------------------------------------------
+
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-26 01:33:10 +0000