libwebp/src/enc/cost.c

// Copyright 2011 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.
// -----------------------------------------------------------------------------
//
// Cost tables for level and modes
//
// Author: Skal (pascal.massimino@gmail.com)

#include "./cost.h"

//------------------------------------------------------------------------------
// Boolean-cost cost table

const uint16_t VP8EntropyCost[256] = {
  1792, 1792, 1792, 1536, 1536, 1408, 1366, 1280, 1280, 1216,
  1178, 1152, 1110, 1076, 1061, 1024, 1024,  992,  968,  951,
   939,  911,  896,  878,  871,  854,  838,  820,  811,  794,
   786,  768,  768,  752,  740,  732,  720,  709,  704,  690,
   683,  672,  666,  655,  647,  640,  631,  622,  615,  607,
   598,  592,  586,  576,  572,  564,  559,  555,  547,  541,
   534,  528,  522,  512,  512,  504,  500,  494,  488,  483,
   477,  473,  467,  461,  458,  452,  448,  443,  438,  434,
   427,  424,  419,  415,  410,  406,  403,  399,  394,  390,
   384,  384,  377,  374,  370,  366,  362,  359,  355,  351,
   347,  342,  342,  336,  333,  330,  326,  323,  320,  316,
   312,  308,  305,  302,  299,  296,  293,  288,  287,  283,
   280,  277,  274,  272,  268,  266,  262,  256,  256,  256,
   251,  248,  245,  242,  240,  237,  234,  232,  228,  226,
   223,  221,  218,  216,  214,  211,  208,  205,  203,  201,
   198,  196,  192,  191,  188,  187,  183,  181,  179,  176,
   175,  171,  171,  168,  165,  163,  160,  159,  156,  154,
   152,  150,  148,  146,  144,  142,  139,  138,  135,  133,
   131,  128,  128,  125,  123,  121,  119,  117,  115,  113,
   111,  110,  107,  105,  103,  102,  100,   98,   96,   94,
    92,   91,   89,   86,   86,   83,   82,   80,   77,   76,
    74,   73,   71,   69,   67,   66,   64,   63,   61,   59,
    57,   55,   54,   52,   51,   49,   47,   46,   44,   43,
    41,   40,   38,   36,   35,   33,   32,   30,   29,   27,
    25,   24,   22,   21,   19,   18,   16,   15,   13,   12,
    10,    9,    7,    6,    4,    3
};

//------------------------------------------------------------------------------
// Level cost tables

// For each given level, the following table gives the pattern of contexts to
// use for coding it (in [][0]) as well as the bit value to use for each
// context (in [][1]).
const uint16_t VP8LevelCodes[MAX_VARIABLE_LEVEL][2] = {
                  {0x001, 0x000}, {0x007, 0x001}, {0x00f, 0x005},
  {0x00f, 0x00d}, {0x033, 0x003}, {0x033, 0x003}, {0x033, 0x023},
  {0x033, 0x023}, {0x033, 0x023}, {0x033, 0x023}, {0x0d3, 0x013},
  {0x0d3, 0x013}, {0x0d3, 0x013}, {0x0d3, 0x013}, {0x0d3, 0x013},
  {0x0d3, 0x013}, {0x0d3, 0x013}, {0x0d3, 0x013}, {0x0d3, 0x093},
  {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093},
  {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093},
  {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093},
  {0x0d3, 0x093}, {0x0d3, 0x093}, {0x0d3, 0x093}, {0x153, 0x053},
  {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
  {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
  {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
  {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
  {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
  {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
  {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053},
  {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x053}, {0x153, 0x153}
};

// fixed costs for coding levels, deduce from the coding tree.
// This is only the part that doesn't depend on the probability state.
const uint16_t VP8LevelFixedCosts[MAX_LEVEL + 1] = {
     0,  256,  256,  256,  256,  432,  618,  630,
   731,  640,  640,  828,  901,  948, 1021, 1101,
  1174, 1221, 1294, 1042, 1085, 1115, 1158, 1202,
  1245, 1275, 1318, 1337, 1380, 1410, 1453, 1497,
  1540, 1570, 1613, 1280, 1295, 1317, 1332, 1358,
  1373, 1395, 1410, 1454, 1469, 1491, 1506, 1532,
  1547, 1569, 1584, 1601, 1616, 1638, 1653, 1679,
  1694, 1716, 1731, 1775, 1790, 1812, 1827, 1853,
  1868, 1890, 1905, 1727, 1733, 1742, 1748, 1759,
  1765, 1774, 1780, 1800, 1806, 1815, 1821, 1832,
  1838, 1847, 1853, 1878, 1884, 1893, 1899, 1910,
  1916, 1925, 1931, 1951, 1957, 1966, 1972, 1983,
  1989, 1998, 2004, 2027, 2033, 2042, 2048, 2059,
  2065, 2074, 2080, 2100, 2106, 2115, 2121, 2132,
  2138, 2147, 2153, 2178, 2184, 2193, 2199, 2210,
  2216, 2225, 2231, 2251, 2257, 2266, 2272, 2283,
  2289, 2298, 2304, 2168, 2174, 2183, 2189, 2200,
  2206, 2215, 2221, 2241, 2247, 2256, 2262, 2273,
  2279, 2288, 2294, 2319, 2325, 2334, 2340, 2351,
  2357, 2366, 2372, 2392, 2398, 2407, 2413, 2424,
  2430, 2439, 2445, 2468, 2474, 2483, 2489, 2500,
  2506, 2515, 2521, 2541, 2547, 2556, 2562, 2573,
  2579, 2588, 2594, 2619, 2625, 2634, 2640, 2651,
  2657, 2666, 2672, 2692, 2698, 2707, 2713, 2724,
  2730, 2739, 2745, 2540, 2546, 2555, 2561, 2572,
  2578, 2587, 2593, 2613, 2619, 2628, 2634, 2645,
  2651, 2660, 2666, 2691, 2697, 2706, 2712, 2723,
  2729, 2738, 2744, 2764, 2770, 2779, 2785, 2796,
  2802, 2811, 2817, 2840, 2846, 2855, 2861, 2872,
  2878, 2887, 2893, 2913, 2919, 2928, 2934, 2945,
  2951, 2960, 2966, 2991, 2997, 3006, 3012, 3023,
  3029, 3038, 3044, 3064, 3070, 3079, 3085, 3096,
  3102, 3111, 3117, 2981, 2987, 2996, 3002, 3013,
  3019, 3028, 3034, 3054, 3060, 3069, 3075, 3086,
  3092, 3101, 3107, 3132, 3138, 3147, 3153, 3164,
  3170, 3179, 3185, 3205, 3211, 3220, 3226, 3237,
  3243, 3252, 3258, 3281, 3287, 3296, 3302, 3313,
  3319, 3328, 3334, 3354, 3360, 3369, 3375, 3386,
  3392, 3401, 3407, 3432, 3438, 3447, 3453, 3464,
  3470, 3479, 3485, 3505, 3511, 3520, 3526, 3537,
  3543, 3552, 3558, 2816, 2822, 2831, 2837, 2848,
  2854, 2863, 2869, 2889, 2895, 2904, 2910, 2921,
  2927, 2936, 2942, 2967, 2973, 2982, 2988, 2999,
  3005, 3014, 3020, 3040, 3046, 3055, 3061, 3072,
  3078, 3087, 3093, 3116, 3122, 3131, 3137, 3148,
  3154, 3163, 3169, 3189, 3195, 3204, 3210, 3221,
  3227, 3236, 3242, 3267, 3273, 3282, 3288, 3299,
  3305, 3314, 3320, 3340, 3346, 3355, 3361, 3372,
  3378, 3387, 3393, 3257, 3263, 3272, 3278, 3289,
  3295, 3304, 3310, 3330, 3336, 3345, 3351, 3362,
  3368, 3377, 3383, 3408, 3414, 3423, 3429, 3440,
  3446, 3455, 3461, 3481, 3487, 3496, 3502, 3513,
  3519, 3528, 3534, 3557, 3563, 3572, 3578, 3589,
  3595, 3604, 3610, 3630, 3636, 3645, 3651, 3662,
  3668, 3677, 3683, 3708, 3714, 3723, 3729, 3740,
  3746, 3755, 3761, 3781, 3787, 3796, 3802, 3813,
  3819, 3828, 3834, 3629, 3635, 3644, 3650, 3661,
  3667, 3676, 3682, 3702, 3708, 3717, 3723, 3734,
  3740, 3749, 3755, 3780, 3786, 3795, 3801, 3812,
  3818, 3827, 3833, 3853, 3859, 3868, 3874, 3885,
  3891, 3900, 3906, 3929, 3935, 3944, 3950, 3961,
  3967, 3976, 3982, 4002, 4008, 4017, 4023, 4034,
  4040, 4049, 4055, 4080, 4086, 4095, 4101, 4112,
  4118, 4127, 4133, 4153, 4159, 4168, 4174, 4185,
  4191, 4200, 4206, 4070, 4076, 4085, 4091, 4102,
  4108, 4117, 4123, 4143, 4149, 4158, 4164, 4175,
  4181, 4190, 4196, 4221, 4227, 4236, 4242, 4253,
  4259, 4268, 4274, 4294, 4300, 4309, 4315, 4326,
  4332, 4341, 4347, 4370, 4376, 4385, 4391, 4402,
  4408, 4417, 4423, 4443, 4449, 4458, 4464, 4475,
  4481, 4490, 4496, 4521, 4527, 4536, 4542, 4553,
  4559, 4568, 4574, 4594, 4600, 4609, 4615, 4626,
  4632, 4641, 4647, 3515, 3521, 3530, 3536, 3547,
  3553, 3562, 3568, 3588, 3594, 3603, 3609, 3620,
  3626, 3635, 3641, 3666, 3672, 3681, 3687, 3698,
  3704, 3713, 3719, 3739, 3745, 3754, 3760, 3771,
  3777, 3786, 3792, 3815, 3821, 3830, 3836, 3847,
  3853, 3862, 3868, 3888, 3894, 3903, 3909, 3920,
  3926, 3935, 3941, 3966, 3972, 3981, 3987, 3998,
  4004, 4013, 4019, 4039, 4045, 4054, 4060, 4071,
  4077, 4086, 4092, 3956, 3962, 3971, 3977, 3988,
  3994, 4003, 4009, 4029, 4035, 4044, 4050, 4061,
  4067, 4076, 4082, 4107, 4113, 4122, 4128, 4139,
  4145, 4154, 4160, 4180, 4186, 4195, 4201, 4212,
  4218, 4227, 4233, 4256, 4262, 4271, 4277, 4288,
  4294, 4303, 4309, 4329, 4335, 4344, 4350, 4361,
  4367, 4376, 4382, 4407, 4413, 4422, 4428, 4439,
  4445, 4454, 4460, 4480, 4486, 4495, 4501, 4512,
  4518, 4527, 4533, 4328, 4334, 4343, 4349, 4360,
  4366, 4375, 4381, 4401, 4407, 4416, 4422, 4433,
  4439, 4448, 4454, 4479, 4485, 4494, 4500, 4511,
  4517, 4526, 4532, 4552, 4558, 4567, 4573, 4584,
  4590, 4599, 4605, 4628, 4634, 4643, 4649, 4660,
  4666, 4675, 4681, 4701, 4707, 4716, 4722, 4733,
  4739, 4748, 4754, 4779, 4785, 4794, 4800, 4811,
  4817, 4826, 4832, 4852, 4858, 4867, 4873, 4884,
  4890, 4899, 4905, 4769, 4775, 4784, 4790, 4801,
  4807, 4816, 4822, 4842, 4848, 4857, 4863, 4874,
  4880, 4889, 4895, 4920, 4926, 4935, 4941, 4952,
  4958, 4967, 4973, 4993, 4999, 5008, 5014, 5025,
  5031, 5040, 5046, 5069, 5075, 5084, 5090, 5101,
  5107, 5116, 5122, 5142, 5148, 5157, 5163, 5174,
  5180, 5189, 5195, 5220, 5226, 5235, 5241, 5252,
  5258, 5267, 5273, 5293, 5299, 5308, 5314, 5325,
  5331, 5340, 5346, 4604, 4610, 4619, 4625, 4636,
  4642, 4651, 4657, 4677, 4683, 4692, 4698, 4709,
  4715, 4724, 4730, 4755, 4761, 4770, 4776, 4787,
  4793, 4802, 4808, 4828, 4834, 4843, 4849, 4860,
  4866, 4875, 4881, 4904, 4910, 4919, 4925, 4936,
  4942, 4951, 4957, 4977, 4983, 4992, 4998, 5009,
  5015, 5024, 5030, 5055, 5061, 5070, 5076, 5087,
  5093, 5102, 5108, 5128, 5134, 5143, 5149, 5160,
  5166, 5175, 5181, 5045, 5051, 5060, 5066, 5077,
  5083, 5092, 5098, 5118, 5124, 5133, 5139, 5150,
  5156, 5165, 5171, 5196, 5202, 5211, 5217, 5228,
  5234, 5243, 5249, 5269, 5275, 5284, 5290, 5301,
  5307, 5316, 5322, 5345, 5351, 5360, 5366, 5377,
  5383, 5392, 5398, 5418, 5424, 5433, 5439, 5450,
  5456, 5465, 5471, 5496, 5502, 5511, 5517, 5528,
  5534, 5543, 5549, 5569, 5575, 5584, 5590, 5601,
  5607, 5616, 5622, 5417, 5423, 5432, 5438, 5449,
  5455, 5464, 5470, 5490, 5496, 5505, 5511, 5522,
  5528, 5537, 5543, 5568, 5574, 5583, 5589, 5600,
  5606, 5615, 5621, 5641, 5647, 5656, 5662, 5673,
  5679, 5688, 5694, 5717, 5723, 5732, 5738, 5749,
  5755, 5764, 5770, 5790, 5796, 5805, 5811, 5822,
  5828, 5837, 5843, 5868, 5874, 5883, 5889, 5900,
  5906, 5915, 5921, 5941, 5947, 5956, 5962, 5973,
  5979, 5988, 5994, 5858, 5864, 5873, 5879, 5890,
  5896, 5905, 5911, 5931, 5937, 5946, 5952, 5963,
  5969, 5978, 5984, 6009, 6015, 6024, 6030, 6041,
  6047, 6056, 6062, 6082, 6088, 6097, 6103, 6114,
  6120, 6129, 6135, 6158, 6164, 6173, 6179, 6190,
  6196, 6205, 6211, 6231, 6237, 6246, 6252, 6263,
  6269, 6278, 6284, 6309, 6315, 6324, 6330, 6341,
  6347, 6356, 6362, 6382, 6388, 6397, 6403, 6414,
  6420, 6429, 6435, 3515, 3521, 3530, 3536, 3547,
  3553, 3562, 3568, 3588, 3594, 3603, 3609, 3620,
  3626, 3635, 3641, 3666, 3672, 3681, 3687, 3698,
  3704, 3713, 3719, 3739, 3745, 3754, 3760, 3771,
  3777, 3786, 3792, 3815, 3821, 3830, 3836, 3847,
  3853, 3862, 3868, 3888, 3894, 3903, 3909, 3920,
  3926, 3935, 3941, 3966, 3972, 3981, 3987, 3998,
  4004, 4013, 4019, 4039, 4045, 4054, 4060, 4071,
  4077, 4086, 4092, 3956, 3962, 3971, 3977, 3988,
  3994, 4003, 4009, 4029, 4035, 4044, 4050, 4061,
  4067, 4076, 4082, 4107, 4113, 4122, 4128, 4139,
  4145, 4154, 4160, 4180, 4186, 4195, 4201, 4212,
  4218, 4227, 4233, 4256, 4262, 4271, 4277, 4288,
  4294, 4303, 4309, 4329, 4335, 4344, 4350, 4361,
  4367, 4376, 4382, 4407, 4413, 4422, 4428, 4439,
  4445, 4454, 4460, 4480, 4486, 4495, 4501, 4512,
  4518, 4527, 4533, 4328, 4334, 4343, 4349, 4360,
  4366, 4375, 4381, 4401, 4407, 4416, 4422, 4433,
  4439, 4448, 4454, 4479, 4485, 4494, 4500, 4511,
  4517, 4526, 4532, 4552, 4558, 4567, 4573, 4584,
  4590, 4599, 4605, 4628, 4634, 4643, 4649, 4660,
  4666, 4675, 4681, 4701, 4707, 4716, 4722, 4733,
  4739, 4748, 4754, 4779, 4785, 4794, 4800, 4811,
  4817, 4826, 4832, 4852, 4858, 4867, 4873, 4884,
  4890, 4899, 4905, 4769, 4775, 4784, 4790, 4801,
  4807, 4816, 4822, 4842, 4848, 4857, 4863, 4874,
  4880, 4889, 4895, 4920, 4926, 4935, 4941, 4952,
  4958, 4967, 4973, 4993, 4999, 5008, 5014, 5025,
  5031, 5040, 5046, 5069, 5075, 5084, 5090, 5101,
  5107, 5116, 5122, 5142, 5148, 5157, 5163, 5174,
  5180, 5189, 5195, 5220, 5226, 5235, 5241, 5252,
  5258, 5267, 5273, 5293, 5299, 5308, 5314, 5325,
  5331, 5340, 5346, 4604, 4610, 4619, 4625, 4636,
  4642, 4651, 4657, 4677, 4683, 4692, 4698, 4709,
  4715, 4724, 4730, 4755, 4761, 4770, 4776, 4787,
  4793, 4802, 4808, 4828, 4834, 4843, 4849, 4860,
  4866, 4875, 4881, 4904, 4910, 4919, 4925, 4936,
  4942, 4951, 4957, 4977, 4983, 4992, 4998, 5009,
  5015, 5024, 5030, 5055, 5061, 5070, 5076, 5087,
  5093, 5102, 5108, 5128, 5134, 5143, 5149, 5160,
  5166, 5175, 5181, 5045, 5051, 5060, 5066, 5077,
  5083, 5092, 5098, 5118, 5124, 5133, 5139, 5150,
  5156, 5165, 5171, 5196, 5202, 5211, 5217, 5228,
  5234, 5243, 5249, 5269, 5275, 5284, 5290, 5301,
  5307, 5316, 5322, 5345, 5351, 5360, 5366, 5377,
  5383, 5392, 5398, 5418, 5424, 5433, 5439, 5450,
  5456, 5465, 5471, 5496, 5502, 5511, 5517, 5528,
  5534, 5543, 5549, 5569, 5575, 5584, 5590, 5601,
  5607, 5616, 5622, 5417, 5423, 5432, 5438, 5449,
  5455, 5464, 5470, 5490, 5496, 5505, 5511, 5522,
  5528, 5537, 5543, 5568, 5574, 5583, 5589, 5600,
  5606, 5615, 5621, 5641, 5647, 5656, 5662, 5673,
  5679, 5688, 5694, 5717, 5723, 5732, 5738, 5749,
  5755, 5764, 5770, 5790, 5796, 5805, 5811, 5822,
  5828, 5837, 5843, 5868, 5874, 5883, 5889, 5900,
  5906, 5915, 5921, 5941, 5947, 5956, 5962, 5973,
  5979, 5988, 5994, 5858, 5864, 5873, 5879, 5890,
  5896, 5905, 5911, 5931, 5937, 5946, 5952, 5963,
  5969, 5978, 5984, 6009, 6015, 6024, 6030, 6041,
  6047, 6056, 6062, 6082, 6088, 6097, 6103, 6114,
  6120, 6129, 6135, 6158, 6164, 6173, 6179, 6190,
  6196, 6205, 6211, 6231, 6237, 6246, 6252, 6263,
  6269, 6278, 6284, 6309, 6315, 6324, 6330, 6341,
  6347, 6356, 6362, 6382, 6388, 6397, 6403, 6414,
  6420, 6429, 6435, 5303, 5309, 5318, 5324, 5335,
  5341, 5350, 5356, 5376, 5382, 5391, 5397, 5408,
  5414, 5423, 5429, 5454, 5460, 5469, 5475, 5486,
  5492, 5501, 5507, 5527, 5533, 5542, 5548, 5559,
  5565, 5574, 5580, 5603, 5609, 5618, 5624, 5635,
  5641, 5650, 5656, 5676, 5682, 5691, 5697, 5708,
  5714, 5723, 5729, 5754, 5760, 5769, 5775, 5786,
  5792, 5801, 5807, 5827, 5833, 5842, 5848, 5859,
  5865, 5874, 5880, 5744, 5750, 5759, 5765, 5776,
  5782, 5791, 5797, 5817, 5823, 5832, 5838, 5849,
  5855, 5864, 5870, 5895, 5901, 5910, 5916, 5927,
  5933, 5942, 5948, 5968, 5974, 5983, 5989, 6000,
  6006, 6015, 6021, 6044, 6050, 6059, 6065, 6076,
  6082, 6091, 6097, 6117, 6123, 6132, 6138, 6149,
  6155, 6164, 6170, 6195, 6201, 6210, 6216, 6227,
  6233, 6242, 6248, 6268, 6274, 6283, 6289, 6300,
  6306, 6315, 6321, 6116, 6122, 6131, 6137, 6148,
  6154, 6163, 6169, 6189, 6195, 6204, 6210, 6221,
  6227, 6236, 6242, 6267, 6273, 6282, 6288, 6299,
  6305, 6314, 6320, 6340, 6346, 6355, 6361, 6372,
  6378, 6387, 6393, 6416, 6422, 6431, 6437, 6448,
  6454, 6463, 6469, 6489, 6495, 6504, 6510, 6521,
  6527, 6536, 6542, 6567, 6573, 6582, 6588, 6599,
  6605, 6614, 6620, 6640, 6646, 6655, 6661, 6672,
  6678, 6687, 6693, 6557, 6563, 6572, 6578, 6589,
  6595, 6604, 6610, 6630, 6636, 6645, 6651, 6662,
  6668, 6677, 6683, 6708, 6714, 6723, 6729, 6740,
  6746, 6755, 6761, 6781, 6787, 6796, 6802, 6813,
  6819, 6828, 6834, 6857, 6863, 6872, 6878, 6889,
  6895, 6904, 6910, 6930, 6936, 6945, 6951, 6962,
  6968, 6977, 6983, 7008, 7014, 7023, 7029, 7040,
  7046, 7055, 7061, 7081, 7087, 7096, 7102, 7113,
  7119, 7128, 7134, 6392, 6398, 6407, 6413, 6424,
  6430, 6439, 6445, 6465, 6471, 6480, 6486, 6497,
  6503, 6512, 6518, 6543, 6549, 6558, 6564, 6575,
  6581, 6590, 6596, 6616, 6622, 6631, 6637, 6648,
  6654, 6663, 6669, 6692, 6698, 6707, 6713, 6724,
  6730, 6739, 6745, 6765, 6771, 6780, 6786, 6797,
  6803, 6812, 6818, 6843, 6849, 6858, 6864, 6875,
  6881, 6890, 6896, 6916, 6922, 6931, 6937, 6948,
  6954, 6963, 6969, 6833, 6839, 6848, 6854, 6865,
  6871, 6880, 6886, 6906, 6912, 6921, 6927, 6938,
  6944, 6953, 6959, 6984, 6990, 6999, 7005, 7016,
  7022, 7031, 7037, 7057, 7063, 7072, 7078, 7089,
  7095, 7104, 7110, 7133, 7139, 7148, 7154, 7165,
  7171, 7180, 7186, 7206, 7212, 7221, 7227, 7238,
  7244, 7253, 7259, 7284, 7290, 7299, 7305, 7316,
  7322, 7331, 7337, 7357, 7363, 7372, 7378, 7389,
  7395, 7404, 7410, 7205, 7211, 7220, 7226, 7237,
  7243, 7252, 7258, 7278, 7284, 7293, 7299, 7310,
  7316, 7325, 7331, 7356, 7362, 7371, 7377, 7388,
  7394, 7403, 7409, 7429, 7435, 7444, 7450, 7461,
  7467, 7476, 7482, 7505, 7511, 7520, 7526, 7537,
  7543, 7552, 7558, 7578, 7584, 7593, 7599, 7610,
  7616, 7625, 7631, 7656, 7662, 7671, 7677, 7688,
  7694, 7703, 7709, 7729, 7735, 7744, 7750, 7761
};

static int VariableLevelCost(int level, const uint8_t probas[NUM_PROBAS]) {
  int pattern = VP8LevelCodes[level - 1][0];
  int bits = VP8LevelCodes[level - 1][1];
  int cost = 0;
  int i;
  for (i = 2; pattern; ++i) {
    if (pattern & 1) {
      cost += VP8BitCost(bits & 1, probas[i]);
    }
    bits >>= 1;
    pattern >>= 1;
  }
  return cost;
}

//------------------------------------------------------------------------------
// Pre-calc level costs once for all

void VP8CalculateLevelCosts(VP8Proba* const proba) {
  int ctype, band, ctx;

  if (!proba->dirty_) return;  // nothing to do.

  for (ctype = 0; ctype < NUM_TYPES; ++ctype) {
    for (band = 0; band < NUM_BANDS; ++band) {
      for (ctx = 0; ctx < NUM_CTX; ++ctx) {
        const uint8_t* const p = proba->coeffs_[ctype][band][ctx];
        uint16_t* const table = proba->level_cost_[ctype][band][ctx];
        const int cost0 = (ctx > 0) ? VP8BitCost(1, p[0]) : 0;
        const int cost_base = VP8BitCost(1, p[1]) + cost0;
        int v;
        table[0] = VP8BitCost(0, p[1]) + cost0;
        for (v = 1; v <= MAX_VARIABLE_LEVEL; ++v) {
          table[v] = cost_base + VariableLevelCost(v, p);
        }
        // Starting at level 67 and up, the variable part of the cost is
        // actually constant.
      }
    }
  }
  proba->dirty_ = 0;
}

//------------------------------------------------------------------------------
// Mode cost tables.

// These are the fixed probabilities (in the coding trees) turned into bit-cost
// by calling VP8BitCost().
const uint16_t VP8FixedCostsUV[4] = { 302, 984, 439, 642 };
// note: these values include the fixed VP8BitCost(1, 145) mode selection cost.
const uint16_t VP8FixedCostsI16[4] = { 663, 919, 872, 919 };
const uint16_t VP8FixedCostsI4[NUM_BMODES][NUM_BMODES][NUM_BMODES] = {
  { {   40, 1151, 1723, 1874, 2103, 2019, 1628, 1777, 2226, 2137 },
    {  192,  469, 1296, 1308, 1849, 1794, 1781, 1703, 1713, 1522 },
    {  142,  910,  762, 1684, 1849, 1576, 1460, 1305, 1801, 1657 },
    {  559,  641, 1370,  421, 1182, 1569, 1612, 1725,  863, 1007 },
    {  299, 1059, 1256, 1108,  636, 1068, 1581, 1883,  869, 1142 },
    {  277, 1111,  707, 1362, 1089,  672, 1603, 1541, 1545, 1291 },
    {  214,  781, 1609, 1303, 1632, 2229,  726, 1560, 1713,  918 },
    {  152, 1037, 1046, 1759, 1983, 2174, 1358,  742, 1740, 1390 },
    {  512, 1046, 1420,  753,  752, 1297, 1486, 1613,  460, 1207 },
    {  424,  827, 1362,  719, 1462, 1202, 1199, 1476, 1199,  538 } },
  { {  240,  402, 1134, 1491, 1659, 1505, 1517, 1555, 1979, 2099 },
    {  467,  242,  960, 1232, 1714, 1620, 1834, 1570, 1676, 1391 },
    {  500,  455,  463, 1507, 1699, 1282, 1564,  982, 2114, 2114 },
    {  672,  643, 1372,  331, 1589, 1667, 1453, 1938,  996,  876 },
    {  458,  783, 1037,  911,  738,  968, 1165, 1518,  859, 1033 },
    {  504,  815,  504, 1139, 1219,  719, 1506, 1085, 1268, 1268 },
    {  333,  630, 1445, 1239, 1883, 3672,  799, 1548, 1865,  598 },
    {  399,  644,  746, 1342, 1856, 1350, 1493,  613, 1855, 1015 },
    {  622,  749, 1205,  608, 1066, 1408, 1290, 1406,  546,  971 },
    {  500,  753, 1041,  668, 1230, 1617, 1297, 1425, 1383,  523 } },
  { {  394,  553,  523, 1502, 1536,  981, 1608, 1142, 1666, 2181 },
    {  655,  430,  375, 1411, 1861, 1220, 1677, 1135, 1978, 1553 },
    {  690,  640,  245, 1954, 2070, 1194, 1528,  982, 1972, 2232 },
    {  559,  834,  741,  867, 1131,  980, 1225,  852, 1092,  784 },
    {  690,  875,  516,  959,  673,  894, 1056, 1190, 1528, 1126 },
    {  740,  951,  384, 1277, 1177,  492, 1579, 1155, 1846, 1513 },
    {  323,  775, 1062, 1776, 3062, 1274,  813, 1188, 1372,  655 },
    {  488,  971,  484, 1767, 1515, 1775, 1115,  503, 1539, 1461 },
    {  740, 1006,  998,  709,  851, 1230, 1337,  788,  741,  721 },
    {  522, 1073,  573, 1045, 1346,  887, 1046, 1146, 1203,  697 } },
  { {  105,  864, 1442, 1009, 1934, 1840, 1519, 1920, 1673, 1579 },
    {  534,  305, 1193,  683, 1388, 2164, 1802, 1894, 1264, 1170 },
    {  305,  518,  877, 1108, 1426, 3215, 1425, 1064, 1320, 1242 },
    {  683,  732, 1927,  257, 1493, 2048, 1858, 1552, 1055,  947 },
    {  394,  814, 1024,  660,  959, 1556, 1282, 1289,  893, 1047 },
    {  528,  615,  996,  940, 1201,  635, 1094, 2515,  803, 1358 },
    {  347,  614, 1609, 1187, 3133, 1345, 1007, 1339, 1017,  667 },
    {  218,  740,  878, 1605, 3650, 3650, 1345,  758, 1357, 1617 },
    {  672,  750, 1541,  558, 1257, 1599, 1870, 2135,  402, 1087 },
    {  592,  684, 1161,  430, 1092, 1497, 1475, 1489, 1095,  822 } },
  { {  228, 1056, 1059, 1368,  752,  982, 1512, 1518,  987, 1782 },
    {  494,  514,  818,  942,  965,  892, 1610, 1356, 1048, 1363 },
    {  512,  648,  591, 1042,  761,  991, 1196, 1454, 1309, 1463 },
    {  683,  749, 1043,  676,  841, 1396, 1133, 1138,  654,  939 },
    {  622, 1101, 1126,  994,  361, 1077, 1203, 1318,  877, 1219 },
    {  631, 1068,  857, 1650,  651,  477, 1650, 1419,  828, 1170 },
    {  555,  727, 1068, 1335, 3127, 1339,  820, 1331, 1077,  429 },
    {  504,  879,  624, 1398,  889,  889, 1392,  808,  891, 1406 },
    {  683, 1602, 1289,  977,  578,  983, 1280, 1708,  406, 1122 },
    {  399,  865, 1433, 1070, 1072,  764,  968, 1477, 1223,  678 } },
  { {  333,  760,  935, 1638, 1010,  529, 1646, 1410, 1472, 2219 },
    {  512,  494,  750, 1160, 1215,  610, 1870, 1868, 1628, 1169 },
    {  572,  646,  492, 1934, 1208,  603, 1580, 1099, 1398, 1995 },
    {  786,  789,  942,  581, 1018,  951, 1599, 1207,  731,  768 },
    {  690, 1015,  672, 1078,  582,  504, 1693, 1438, 1108, 2897 },
    {  768, 1267,  571, 2005, 1243,  244, 2881, 1380, 1786, 1453 },
    {  452,  899, 1293,  903, 1311, 3100,  465, 1311, 1319,  813 },
    {  394,  927,  942, 1103, 1358, 1104,  946,  593, 1363, 1109 },
    {  559, 1005, 1007, 1016,  658, 1173, 1021, 1164,  623, 1028 },
    {  564,  796,  632, 1005, 1014,  863, 2316, 1268,  938,  764 } },
  { {  266,  606, 1098, 1228, 1497, 1243,  948, 1030, 1734, 1461 },
    {  366,  585,  901, 1060, 1407, 1247,  876, 1134, 1620, 1054 },
    {  452,  565,  542, 1729, 1479, 1479, 1016,  886, 2938, 1150 },
    {  555, 1088, 1533,  950, 1354,  895,  834, 1019, 1021,  496 },
    {  704,  815, 1193,  971,  973,  640, 1217, 2214,  832,  578 },
    {  672, 1245,  579,  871,  875,  774,  872, 1273, 1027,  949 },
    {  296, 1134, 2050, 1784, 1636, 3425,  442, 1550, 2076,  722 },
    {  342,  982, 1259, 1846, 1848, 1848,  622,  568, 1847, 1052 },
    {  555, 1064, 1304,  828,  746, 1343, 1075, 1329, 1078,  494 },
    {  288, 1167, 1285, 1174, 1639, 1639,  833, 2254, 1304,  509 } },
  { {  342,  719,  767, 1866, 1757, 1270, 1246,  550, 1746, 2151 },
    {  483,  653,  694, 1509, 1459, 1410, 1218,  507, 1914, 1266 },
    {  488,  757,  447, 2979, 1813, 1268, 1654,  539, 1849, 2109 },
    {  522, 1097, 1085,  851, 1365, 1111,  851,  901,  961,  605 },
    {  709,  716,  841,  728,  736,  945,  941,  862, 2845, 1057 },
    {  512, 1323,  500, 1336, 1083,  681, 1342,  717, 1604, 1350 },
    {  452, 1155, 1372, 1900, 1501, 3290,  311,  944, 1919,  922 },
    {  403, 1520,  977, 2132, 1733, 3522, 1076,  276, 3335, 1547 },
    {  559, 1374, 1101,  615,  673, 2462,  974,  795,  984,  984 },
    {  547, 1122, 1062,  812, 1410,  951, 1140,  622, 1268,  651 } },
  { {  165,  982, 1235,  938, 1334, 1366, 1659, 1578,  964, 1612 },
    {  592,  422,  925,  847, 1139, 1112, 1387, 2036,  861, 1041 },
    {  403,  837,  732,  770,  941, 1658, 1250,  809, 1407, 1407 },
    {  896,  874, 1071,  381, 1568, 1722, 1437, 2192,  480, 1035 },
    {  640, 1098, 1012, 1032,  684, 1382, 1581, 2106,  416,  865 },
    {  559, 1005,  819,  914,  710,  770, 1418,  920,  838, 1435 },
    {  415, 1258, 1245,  870, 1278, 3067,  770, 1021, 1287,  522 },
    {  406,  990,  601, 1009, 1265, 1265, 1267,  759, 1017, 1277 },
    {  968, 1182, 1329,  788, 1032, 1292, 1705, 1714,  203, 1403 },
    {  732,  877, 1279,  471,  901, 1161, 1545, 1294,  755,  755 } },
  { {  111,  931, 1378, 1185, 1933, 1648, 1148, 1714, 1873, 1307 },
    {  406,  414, 1030, 1023, 1910, 1404, 1313, 1647, 1509,  793 },
    {  342,  640,  575, 1088, 1241, 1349, 1161, 1350, 1756, 1502 },
    {  559,  766, 1185,  357, 1682, 1428, 1329, 1897, 1219,  802 },
    {  473,  909, 1164,  771,  719, 2508, 1427, 1432,  722,  782 },
    {  342,  892,  785, 1145, 1150,  794, 1296, 1550,  973, 1057 },
    {  208, 1036, 1326, 1343, 1606, 3395,  815, 1455, 1618,  712 },
    {  228,  928,  890, 1046, 3499, 1711,  994,  829, 1720, 1318 },
    {  768,  724, 1058,  636,  991, 1075, 1319, 1324,  616,  825 },
    {  305, 1167, 1358,  899, 1587, 1587,  987, 1988, 1332,  501 } }
};

//------------------------------------------------------------------------------
// Mode costs

static int GetResidualCost(int ctx0, const VP8Residual* const res) {
  int n = res->first;
  // should be prob[VP8EncBands[n]], but it's equivalent for n=0 or 1
  const int p0 = res->prob[n][ctx0][0];
  const uint16_t* t = res->cost[n][ctx0];
  // bit_cost(1, p0) is already incorporated in t[] tables, but only if ctx != 0
  // (as required by the syntax). For ctx0 == 0, we need to add it here or it'll
  // be missing during the loop.
  int cost = (ctx0 == 0) ? VP8BitCost(1, p0) : 0;

  if (res->last < 0) {
    return VP8BitCost(0, p0);
  }
  for (; n < res->last; ++n) {
    const int v = abs(res->coeffs[n]);
    const int b = VP8EncBands[n + 1];
    const int ctx = (v >= 2) ? 2 : v;
    cost += VP8LevelCost(t, v);
    t = res->cost[b][ctx];
  }
  // Last coefficient is always non-zero
  {
    const int v = abs(res->coeffs[n]);
    assert(v != 0);
    cost += VP8LevelCost(t, v);
    if (n < 15) {
      const int b = VP8EncBands[n + 1];
      const int ctx = (v == 1) ? 1 : 2;
      const int last_p0 = res->prob[b][ctx][0];
      cost += VP8BitCost(0, last_p0);
    }
  }
  return cost;
}

//------------------------------------------------------------------------------
// init function

#if defined(WEBP_USE_MIPS32)
extern int VP8GetResidualCostMIPS32(int ctx0, const VP8Residual* const res);
#endif  // WEBP_USE_MIPS32

// TODO(skal): this, and GetResidualCost(), should probably go somewhere
// under src/dsp/ at some point.
VP8GetResidualCostFunc VP8GetResidualCost;

void VP8GetResidualCostInit(void) {
  if (VP8GetResidualCost == NULL) {
    VP8GetResidualCost = GetResidualCost;
    if (VP8GetCPUInfo != NULL) {
#if defined(WEBP_USE_MIPS32)
      if (VP8GetCPUInfo(kMIPS32)) {
        VP8GetResidualCost = VP8GetResidualCostMIPS32;
      }
#endif
    }
  }
}

//------------------------------------------------------------------------------
// helper functions for residuals struct VP8Residual.

void VP8InitResidual(int first, int coeff_type,
                     VP8Encoder* const enc, VP8Residual* const res) {
  res->coeff_type = coeff_type;
  res->prob  = enc->proba_.coeffs_[coeff_type];
  res->stats = enc->proba_.stats_[coeff_type];
  res->cost  = enc->proba_.level_cost_[coeff_type];
  res->first = first;
}

void VP8SetResidualCoeffs(const int16_t* const coeffs, VP8Residual* const res) {
  int n;
  res->last = -1;
  for (n = 15; n >= res->first; --n) {
    if (coeffs[n]) {
      res->last = n;
      break;
    }
  }
  res->coeffs = coeffs;
}

//------------------------------------------------------------------------------
// Mode costs

int VP8GetCostLuma4(VP8EncIterator* const it, const int16_t levels[16]) {
  const int x = (it->i4_ & 3), y = (it->i4_ >> 2);
  VP8Residual res;
  VP8Encoder* const enc = it->enc_;
  int R = 0;
  int ctx;

  VP8InitResidual(0, 3, enc, &res);
  ctx = it->top_nz_[x] + it->left_nz_[y];
  VP8SetResidualCoeffs(levels, &res);
  R += VP8GetResidualCost(ctx, &res);
  return R;
}

int VP8GetCostLuma16(VP8EncIterator* const it, const VP8ModeScore* const rd) {
  VP8Residual res;
  VP8Encoder* const enc = it->enc_;
  int x, y;
  int R = 0;

  VP8IteratorNzToBytes(it);   // re-import the non-zero context

  // DC
  VP8InitResidual(0, 1, enc, &res);
  VP8SetResidualCoeffs(rd->y_dc_levels, &res);
  R += VP8GetResidualCost(it->top_nz_[8] + it->left_nz_[8], &res);

  // AC
  VP8InitResidual(1, 0, enc, &res);
  for (y = 0; y < 4; ++y) {
    for (x = 0; x < 4; ++x) {
      const int ctx = it->top_nz_[x] + it->left_nz_[y];
      VP8SetResidualCoeffs(rd->y_ac_levels[x + y * 4], &res);
      R += VP8GetResidualCost(ctx, &res);
      it->top_nz_[x] = it->left_nz_[y] = (res.last >= 0);
    }
  }
  return R;
}

int VP8GetCostUV(VP8EncIterator* const it, const VP8ModeScore* const rd) {
  VP8Residual res;
  VP8Encoder* const enc = it->enc_;
  int ch, x, y;
  int R = 0;

  VP8IteratorNzToBytes(it);  // re-import the non-zero context

  VP8InitResidual(0, 2, enc, &res);
  for (ch = 0; ch <= 2; ch += 2) {
    for (y = 0; y < 2; ++y) {
      for (x = 0; x < 2; ++x) {
        const int ctx = it->top_nz_[4 + ch + x] + it->left_nz_[4 + ch + y];
        VP8SetResidualCoeffs(rd->uv_levels[ch * 2 + x + y * 2], &res);
        R += VP8GetResidualCost(ctx, &res);
        it->top_nz_[4 + ch + x] = it->left_nz_[4 + ch + y] = (res.last >= 0);
      }
    }
  }
  return R;
}


//------------------------------------------------------------------------------
// Recording of token probabilities.

// Record proba context used
static int Record(int bit, proba_t* const stats) {
  proba_t p = *stats;
  if (p >= 0xffff0000u) {               // an overflow is inbound.
    p = ((p + 1u) >> 1) & 0x7fff7fffu;  // -> divide the stats by 2.
  }
  // record bit count (lower 16 bits) and increment total count (upper 16 bits).
  p += 0x00010000u + bit;
  *stats = p;
  return bit;
}

// We keep the table-free variant around for reference, in case.
#define USE_LEVEL_CODE_TABLE

// Simulate block coding, but only record statistics.
// Note: no need to record the fixed probas.
int VP8RecordCoeffs(int ctx, const VP8Residual* const res) {
  int n = res->first;
  // should be stats[VP8EncBands[n]], but it's equivalent for n=0 or 1
  proba_t* s = res->stats[n][ctx];
  if (res->last  < 0) {
    Record(0, s + 0);
    return 0;
  }
  while (n <= res->last) {
    int v;
    Record(1, s + 0);  // order of record doesn't matter
    while ((v = res->coeffs[n++]) == 0) {
      Record(0, s + 1);
      s = res->stats[VP8EncBands[n]][0];
    }
    Record(1, s + 1);
    if (!Record(2u < (unsigned int)(v + 1), s + 2)) {  // v = -1 or 1
      s = res->stats[VP8EncBands[n]][1];
    } else {
      v = abs(v);
#if !defined(USE_LEVEL_CODE_TABLE)
      if (!Record(v > 4, s + 3)) {
        if (Record(v != 2, s + 4))
          Record(v == 4, s + 5);
      } else if (!Record(v > 10, s + 6)) {
        Record(v > 6, s + 7);
      } else if (!Record((v >= 3 + (8 << 2)), s + 8)) {
        Record((v >= 3 + (8 << 1)), s + 9);
      } else {
        Record((v >= 3 + (8 << 3)), s + 10);
      }
#else
      if (v > MAX_VARIABLE_LEVEL) {
        v = MAX_VARIABLE_LEVEL;
      }

      {
        const int bits = VP8LevelCodes[v - 1][1];
        int pattern = VP8LevelCodes[v - 1][0];
        int i;
        for (i = 0; (pattern >>= 1) != 0; ++i) {
          const int mask = 2 << i;
          if (pattern & 1) Record(!!(bits & mask), s + 3 + i);
        }
      }
#endif
      s = res->stats[VP8EncBands[n]][2];
    }
  }
  if (n < 16) Record(0, s + 0);
  return 1;
}

//------------------------------------------------------------------------------