/*
 * Copyright 2020 Google LLC
 *
 */

/*
 * Copyright (c) 2020, Alliance for Open Media. All rights reserved
 *
 * This source code is subject to the terms of the BSD 2 Clause License and
 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
 * was not distributed with this source code in the LICENSE file, you can
 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
 * Media Patent License 1.0 was not distributed with this source code in the
 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
 */

#define gauss_bits 11
#define sizeof_int 4
#define luma_subblock_size_y 32
#define luma_subblock_size_x 32
#define chroma_subblock_size_y 16
#define chroma_subblock_size_x 16
#define min_luma_legal_range 16
#define max_luma_legal_range 235
#define min_chroma_legal_range 16
#define max_chroma_legal_range 240

struct GrainParams {
  // This structure is compared element-by-element in the function
  // av1_check_grain_params_equiv: this function must be updated if any changes
  // are made to this structure.
  int apply_grain;
  int update_parameters;
  int num_y_points;   // value: 0..14
  int num_cb_points;  // value: 0..10

  int num_cr_points;   // value: 0..10
  int scaling_shift;   // values : 8..11
  int ar_coeff_lag;    // values:  0..3
  int ar_coeff_shift;  // values : 6..9

  // Shift value: AR coeffs range
  // 6: [-2, 2)
  // 7: [-1, 1)
  // 8: [-0.5, 0.5)
  // 9: [-0.25, 0.25)

  int cb_mult;       // 8 bits
  int cb_luma_mult;  // 8 bits
  int cb_offset;     // 9 bits
  int cr_mult;       // 8 bits

  int cr_luma_mult;  // 8 bits
  int cr_offset;     // 9 bits
  int overlap_flag;
  int clip_to_restricted_range;

  unsigned int bit_depth;  // video bit depth
  int chroma_scaling_from_luma;
  int grain_scale_shift;
  unsigned int random_seed;

  // Y 8 bit values 14*2 = 7*4
  // UV 8 bit values 10*2 = 5*4+2 (padding 2)
  int4 scaling_points[14][2];

  // Y 8 bit values 24 = 6*4
  // UV 8 bit values 25 = 6*4 + 1 (padding 3)
  int4 ar_coeffs[3][25];  // xyz = y, cb, cr
};

struct FilmGrainGenData {
  // RW_ByteBuffer dst;
  GrainParams params;

  int luma_block_size_y;
  int luma_block_size_x;
  int luma_grain_stride;
  int chroma_block_size_y;

  int chroma_block_size_x;
  int chroma_grain_stride;
  int left_pad;
  int top_pad;

  int right_pad;
  int bottom_pad;
  int dst_offset_u;
  int dst_offset_v;

  int4 pred_pos[25][3];
};
// Samples with Gaussian distribution in the range of [-2048, 2047] (12 bits)
// with zero mean and standard deviation of about 512.
// should be divided by 4 for 10-bit range and 16 for 8-bit range.
/*
const int gaussian_sequence[2048] = {
  56,    568,   -180,  172,   124,   -84,   172,   -64,   -900,  24,   820,
  224,   1248,  996,   272,   -8,    -916,  -388,  -732,  -104,  -188, 800,
  112,   -652,  -320,  -376,  140,   -252,  492,   -168,  44,    -788, 588,
  -584,  500,   -228,  12,    680,   272,   -476,  972,   -100,  652,  368,
  432,   -196,  -720,  -192,  1000,  -332,  652,   -136,  -552,  -604, -4,
  192,   -220,  -136,  1000,  -52,   372,   -96,   -624,  124,   -24,  396,
  540,   -12,   -104,  640,   464,   244,   -208,  -84,   368,   -528, -740,
  248,   -968,  -848,  608,   376,   -60,   -292,  -40,   -156,  252,  -292,
  248,   224,   -280,  400,   -244,  244,   -60,   76,    -80,   212,  532,
  340,   128,   -36,   824,   -352,  -60,   -264,  -96,   -612,  416,  -704,
  220,   -204,  640,   -160,  1220,  -408,  900,   336,   20,    -336, -96,
  -792,  304,   48,    -28,   -1232, -1172, -448,  104,   -292,  -520, 244,
  60,    -948,  0,     -708,  268,   108,   356,   -548,  488,   -344, -136,
  488,   -196,  -224,  656,   -236,  -1128, 60,    4,     140,   276,  -676,
  -376,  168,   -108,  464,   8,     564,   64,    240,   308,   -300, -400,
  -456,  -136,  56,    120,   -408,  -116,  436,   504,   -232,  328,  844,
  -164,  -84,   784,   -168,  232,   -224,  348,   -376,  128,   568,  96,
  -1244, -288,  276,   848,   832,   -360,  656,   464,   -384,  -332, -356,
  728,   -388,  160,   -192,  468,   296,   224,   140,   -776,  -100, 280,
  4,     196,   44,    -36,   -648,  932,   16,    1428,  28,    528,  808,
  772,   20,    268,   88,    -332,  -284,  124,   -384,  -448,  208,  -228,
  -1044, -328,  660,   380,   -148,  -300,  588,   240,   540,   28,   136,
  -88,   -436,  256,   296,   -1000, 1400,  0,     -48,   1056,  -136, 264,
  -528,  -1108, 632,   -484,  -592,  -344,  796,   124,   -668,  -768, 388,
  1296,  -232,  -188,  -200,  -288,  -4,    308,   100,   -168,  256,  -500,
  204,   -508,  648,   -136,  372,   -272,  -120,  -1004, -552,  -548, -384,
  548,   -296,  428,   -108,  -8,    -912,  -324,  -224,  -88,   -112, -220,
  -100,  996,   -796,  548,   360,   -216,  180,   428,   -200,  -212, 148,
  96,    148,   284,   216,   -412,  -320,  120,   -300,  -384,  -604, -572,
  -332,  -8,    -180,  -176,  696,   116,   -88,   628,   76,    44,   -516,
  240,   -208,  -40,   100,   -592,  344,   -308,  -452,  -228,  20,   916,
  -1752, -136,  -340,  -804,  140,   40,    512,   340,   248,   184,  -492,
  896,   -156,  932,   -628,  328,   -688,  -448,  -616,  -752,  -100, 560,
  -1020, 180,   -800,  -64,   76,    576,   1068,  396,   660,   552,  -108,
  -28,   320,   -628,  312,   -92,   -92,   -472,  268,   16,    560,  516,
  -672,  -52,   492,   -100,  260,   384,   284,   292,   304,   -148, 88,
  -152,  1012,  1064,  -228,  164,   -376,  -684,  592,   -392,  156,  196,
  -524,  -64,   -884,  160,   -176,  636,   648,   404,   -396,  -436, 864,
  424,   -728,  988,   -604,  904,   -592,  296,   -224,  536,   -176, -920,
  436,   -48,   1176,  -884,  416,   -776,  -824,  -884,  524,   -548, -564,
  -68,   -164,  -96,   692,   364,   -692,  -1012, -68,   260,   -480, 876,
  -1116, 452,   -332,  -352,  892,   -1088, 1220,  -676,  12,    -292, 244,
  496,   372,   -32,   280,   200,   112,   -440,  -96,   24,    -644, -184,
  56,    -432,  224,   -980,  272,   -260,  144,   -436,  420,   356,  364,
  -528,  76,    172,   -744,  -368,  404,   -752,  -416,  684,   -688, 72,
  540,   416,   92,    444,   480,   -72,   -1416, 164,   -1172, -68,  24,
  424,   264,   1040,  128,   -912,  -524,  -356,  64,    876,   -12,  4,
  -88,   532,   272,   -524,  320,   276,   -508,  940,   24,    -400, -120,
  756,   60,    236,   -412,  100,   376,   -484,  400,   -100,  -740, -108,
  -260,  328,   -268,  224,   -200,  -416,  184,   -604,  -564,  -20,  296,
  60,    892,   -888,  60,    164,   68,    -760,  216,   -296,  904,  -336,
  -28,   404,   -356,  -568,  -208,  -1480, -512,  296,   328,   -360, -164,
  -1560, -776,  1156,  -428,  164,   -504,  -112,  120,   -216,  -148, -264,
  308,   32,    64,    -72,   72,    116,   176,   -64,   -272,  460,  -536,
  -784,  -280,  348,   108,   -752,  -132,  524,   -540,  -776,  116,  -296,
  -1196, -288,  -560,  1040,  -472,  116,   -848,  -1116, 116,   636,  696,
  284,   -176,  1016,  204,   -864,  -648,  -248,  356,   972,   -584, -204,
  264,   880,   528,   -24,   -184,  116,   448,   -144,  828,   524,  212,
  -212,  52,    12,    200,   268,   -488,  -404,  -880,  824,   -672, -40,
  908,   -248,  500,   716,   -576,  492,   -576,  16,    720,   -108, 384,
  124,   344,   280,   576,   -500,  252,   104,   -308,  196,   -188, -8,
  1268,  296,   1032,  -1196, 436,   316,   372,   -432,  -200,  -660, 704,
  -224,  596,   -132,  268,   32,    -452,  884,   104,   -1008, 424,  -1348,
  -280,  4,     -1168, 368,   476,   696,   300,   -8,    24,    180,  -592,
  -196,  388,   304,   500,   724,   -160,  244,   -84,   272,   -256, -420,
  320,   208,   -144,  -156,  156,   364,   452,   28,    540,   316,  220,
  -644,  -248,  464,   72,    360,   32,    -388,  496,   -680,  -48,  208,
  -116,  -408,  60,    -604,  -392,  548,   -840,  784,   -460,  656,  -544,
  -388,  -264,  908,   -800,  -628,  -612,  -568,  572,   -220,  164,  288,
  -16,   -308,  308,   -112,  -636,  -760,  280,   -668,  432,   364,  240,
  -196,  604,   340,   384,   196,   592,   -44,   -500,  432,   -580, -132,
  636,   -76,   392,   4,     -412,  540,   508,   328,   -356,  -36,  16,
  -220,  -64,   -248,  -60,   24,    -192,  368,   1040,  92,    -24,  -1044,
  -32,   40,    104,   148,   192,   -136,  -520,  56,    -816,  -224, 732,
  392,   356,   212,   -80,   -424,  -1008, -324,  588,   -1496, 576,  460,
  -816,  -848,  56,    -580,  -92,   -1372, -112,  -496,  200,   364,  52,
  -140,  48,    -48,   -60,   84,    72,    40,    132,   -356,  -268, -104,
  -284,  -404,  732,   -520,  164,   -304,  -540,  120,   328,   -76,  -460,
  756,   388,   588,   236,   -436,  -72,   -176,  -404,  -316,  -148, 716,
  -604,  404,   -72,   -88,   -888,  -68,   944,   88,    -220,  -344, 960,
  472,   460,   -232,  704,   120,   832,   -228,  692,   -508,  132,  -476,
  844,   -748,  -364,  -44,   1116,  -1104, -1056, 76,    428,   552,  -692,
  60,    356,   96,    -384,  -188,  -612,  -576,  736,   508,   892,  352,
  -1132, 504,   -24,   -352,  324,   332,   -600,  -312,  292,   508,  -144,
  -8,    484,   48,    284,   -260,  -240,  256,   -100,  -292,  -204, -44,
  472,   -204,  908,   -188,  -1000, -256,  92,    1164,  -392,  564,  356,
  652,   -28,   -884,  256,   484,   -192,  760,   -176,  376,   -524, -452,
  -436,  860,   -736,  212,   124,   504,   -476,  468,   76,    -472, 552,
  -692,  -944,  -620,  740,   -240,  400,   132,   20,    192,   -196, 264,
  -668,  -1012, -60,   296,   -316,  -828,  76,    -156,  284,   -768, -448,
  -832,  148,   248,   652,   616,   1236,  288,   -328,  -400,  -124, 588,
  220,   520,   -696,  1032,  768,   -740,  -92,   -272,  296,   448,  -464,
  412,   -200,  392,   440,   -200,  264,   -152,  -260,  320,   1032, 216,
  320,   -8,    -64,   156,   -1016, 1084,  1172,  536,   484,   -432, 132,
  372,   -52,   -256,  84,    116,   -352,  48,    116,   304,   -384, 412,
  924,   -300,  528,   628,   180,   648,   44,    -980,  -220,  1320, 48,
  332,   748,   524,   -268,  -720,  540,   -276,  564,   -344,  -208, -196,
  436,   896,   88,    -392,  132,   80,    -964,  -288,  568,   56,   -48,
  -456,  888,   8,     552,   -156,  -292,  948,   288,   128,   -716, -292,
  1192,  -152,  876,   352,   -600,  -260,  -812,  -468,  -28,   -120, -32,
  -44,   1284,  496,   192,   464,   312,   -76,   -516,  -380,  -456, -1012,
  -48,   308,   -156,  36,    492,   -156,  -808,  188,   1652,  68,   -120,
  -116,  316,   160,   -140,  352,   808,   -416,  592,   316,   -480, 56,
  528,   -204,  -568,  372,   -232,  752,   -344,  744,   -4,    324,  -416,
  -600,  768,   268,   -248,  -88,   -132,  -420,  -432,  80,    -288, 404,
  -316,  -1216, -588,  520,   -108,  92,    -320,  368,   -480,  -216, -92,
  1688,  -300,  180,   1020,  -176,  820,   -68,   -228,  -260,  436,  -904,
  20,    40,    -508,  440,   -736,  312,   332,   204,   760,   -372, 728,
  96,    -20,   -632,  -520,  -560,  336,   1076,  -64,   -532,  776,  584,
  192,   396,   -728,  -520,  276,   -188,  80,    -52,   -612,  -252, -48,
  648,   212,   -688,  228,   -52,   -260,  428,   -412,  -272,  -404, 180,
  816,   -796,  48,    152,   484,   -88,   -216,  988,   696,   188,  -528,
  648,   -116,  -180,  316,   476,   12,    -564,  96,    476,   -252, -364,
  -376,  -392,  556,   -256,  -576,  260,   -352,  120,   -16,   -136, -260,
  -492,  72,    556,   660,   580,   616,   772,   436,   424,   -32,  -324,
  -1268, 416,   -324,  -80,   920,   160,   228,   724,   32,    -516, 64,
  384,   68,    -128,  136,   240,   248,   -204,  -68,   252,   -932, -120,
  -480,  -628,  -84,   192,   852,   -404,  -288,  -132,  204,   100,  168,
  -68,   -196,  -868,  460,   1080,  380,   -80,   244,   0,     484,  -888,
  64,    184,   352,   600,   460,   164,   604,   -196,  320,   -64,  588,
  -184,  228,   12,    372,   48,    -848,  -344,  224,   208,   -200, 484,
  128,   -20,   272,   -468,  -840,  384,   256,   -720,  -520,  -464, -580,
  112,   -120,  644,   -356,  -208,  -608,  -528,  704,   560,   -424, 392,
  828,   40,    84,    200,   -152,  0,     -144,  584,   280,   -120, 80,
  -556,  -972,  -196,  -472,  724,   80,    168,   -32,   88,    160,  -688,
  0,     160,   356,   372,   -776,  740,   -128,  676,   -248,  -480, 4,
  -364,  96,    544,   232,   -1032, 956,   236,   356,   20,    -40,  300,
  24,    -676,  -596,  132,   1120,  -104,  532,   -1096, 568,   648,  444,
  508,   380,   188,   -376,  -604,  1488,  424,   24,    756,   -220, -192,
  716,   120,   920,   688,   168,   44,    -460,  568,   284,   1144, 1160,
  600,   424,   888,   656,   -356,  -320,  220,   316,   -176,  -724, -188,
  -816,  -628,  -348,  -228,  -380,  1012,  -452,  -660,  736,   928,  404,
  -696,  -72,   -268,  -892,  128,   184,   -344,  -780,  360,   336,  400,
  344,   428,   548,   -112,  136,   -228,  -216,  -820,  -516,  340,  92,
  -136,  116,   -300,  376,   -244,  100,   -316,  -520,  -284,  -12,  824,
  164,   -548,  -180,  -128,  116,   -924,  -828,  268,   -368,  -580, 620,
  192,   160,   0,     -1676, 1068,  424,   -56,   -360,  468,   -156, 720,
  288,   -528,  556,   -364,  548,   -148,  504,   316,   152,   -648, -620,
  -684,  -24,   -376,  -384,  -108,  -920,  -1032, 768,   180,   -264, -508,
  -1268, -260,  -60,   300,   -240,  988,   724,   -376,  -576,  -212, -736,
  556,   192,   1092,  -620,  -880,  376,   -56,   -4,    -216,  -32,  836,
  268,   396,   1332,  864,   -600,  100,   56,    -412,  -92,   356,  180,
  884,   -468,  -436,  292,   -388,  -804,  -704,  -840,  368,   -348, 140,
  -724,  1536,  940,   372,   112,   -372,  436,   -480,  1136,  296,  -32,
  -228,  132,   -48,   -220,  868,   -1016, -60,   -1044, -464,  328,  916,
  244,   12,    -736,  -296,  360,   468,   -376,  -108,  -92,   788,  368,
  -56,   544,   400,   -672,  -420,  728,   16,    320,   44,    -284, -380,
  -796,  488,   132,   204,   -596,  -372,  88,    -152,  -908,  -636, -572,
  -624,  -116,  -692,  -200,  -56,   276,   -88,   484,   -324,  948,  864,
  1000,  -456,  -184,  -276,  292,   -296,  156,   676,   320,   160,  908,
  -84,   -1236, -288,  -116,  260,   -372,  -644,  732,   -756,  -96,  84,
  344,   -520,  348,   -688,  240,   -84,   216,   -1044, -136,  -676, -396,
  -1500, 960,   -40,   176,   168,   1516,  420,   -504,  -344,  -364, -360,
  1216,  -940,  -380,  -212,  252,   -660,  -708,  484,   -444,  -152, 928,
  -120,  1112,  476,   -260,  560,   -148,  -344,  108,   -196,  228,  -288,
  504,   560,   -328,  -88,   288,   -1008, 460,   -228,  468,   -836, -196,
  76,    388,   232,   412,   -1168, -716,  -644,  756,   -172,  -356, -504,
  116,   432,   528,   48,    476,   -168,  -608,  448,   160,   -532, -272,
  28,    -676,  -12,   828,   980,   456,   520,   104,   -104,  256,  -344,
  -4,    -28,   -368,  -52,   -524,  -572,  -556,  -200,  768,   1124, -208,
  -512,  176,   232,   248,   -148,  -888,  604,   -600,  -304,  804,  -156,
  -212,  488,   -192,  -804,  -256,  368,   -360,  -916,  -328,  228,  -240,
  -448,  -472,  856,   -556,  -364,  572,   -12,   -156,  -368,  -340, 432,
  252,   -752,  -152,  288,   268,   -580,  -848,  -592,  108,   -76,  244,
  312,   -716,  592,   -80,   436,   360,   4,     -248,  160,   516,  584,
  732,   44,    -468,  -280,  -292,  -156,  -588,  28,    308,   912,  24,
  124,   156,   180,   -252,  944,   -924,  -772,  -520,  -428,  -624, 300,
  -212,  -1144, 32,    -724,  800,   -1128, -212,  -1288, -848,  180,  -416,
  440,   192,   -576,  -792,  -76,   -1080, 80,    -532,  -352,  -132, 380,
  -820,  148,   1112,  128,   164,   456,   700,   -924,  144,   -668, -384,
  648,   -832,  508,   552,   -52,   -100,  -656,  208,   -568,  748,  -88,
  680,   232,   300,   192,   -408,  -1012, -152,  -252,  -268,  272,  -876,
  -664,  -648,  -332,  -136,  16,    12,    1152,  -28,   332,   -536, 320,
  -672,  -460,  -316,  532,   -260,  228,   -40,   1052,  -816,  180,  88,
  -496,  -556,  -672,  -368,  428,   92,    356,   404,   -408,  252,  196,
  -176,  -556,  792,   268,   32,    372,   40,    96,    -332,  328,  120,
  372,   -900,  -40,   472,   -264,  -592,  952,   128,   656,   112,  664,
  -232,  420,   4,     -344,  -464,  556,   244,   -416,  -32,   252,  0,
  -412,  188,   -696,  508,   -476,  324,   -1096, 656,   -312,  560,  264,
  -136,  304,   160,   -64,   -580,  248,   336,   -720,  560,   -348, -288,
  -276,  -196,  -500,  852,   -544,  -236,  -1128, -992,  -776,  116,  56,
  52,    860,   884,   212,   -12,   168,   1020,  512,   -552,  924,  -148,
  716,   188,   164,   -340,  -520,  -184,  880,   -152,  -680,  -208, -1156,
  -300,  -528,  -472,  364,   100,   -744,  -1056, -32,   540,   280,  144,
  -676,  -32,   -232,  -280,  -224,  96,    568,   -76,   172,   148,  148,
  104,   32,    -296,  -32,   788,   -80,   32,    -16,   280,   288,  944,
  428,   -484
};
*/